DISEASES INFORMATIONS CORNER

Genes essential for the proper muscle development identified

noreply@blogger.com (life hacker) — Wed, 06 Jan 2010 08:46:00 +0000

Tiny DNA Molecules Show Liquid Crystal Phases, Pointing Up New Scenario For First Life On Earth

A team led by the University of Colorado at Boulder and the University of Milan has discovered some unexpected forms of liquid crystals of ultrashort DNA molecules immersed in water, providing a new scenario for a key step in the emergence of life on Earth

A colorful microscope image showing that a solution of tiny DNA molecules has formed a liquid-crystal phase. The DNA molecules pair to form DNA double helices, which, in turn stack end-to-end to make rod-shaped aggregates that orient parallel to one another. (Credit: Michi Nakata)

CU-Boulder physics Professor Noel Clark said the team found that surprisingly short segments of DNA, life’s molecular carrier of genetic information, could assemble into several distinct liquid crystal phases that “self-orient” parallel to one another and stack into columns when placed in a water solution. Life is widely believed to have emerged as segments of DNA- or RNA-like molecules in a prebiotic “soup” solution of ancient organic molecules.

Since the formation of molecular chains as uniform as DNA by random chemistry is essentially impossible, Clark said, scientists have been seeking effective ways for simple molecules to spontaneously self-select, “chain-up” and self-replicate. The new study shows that in a mixture of tiny fragments of DNA, those molecules capable of forming liquid crystals selectively condense into droplets in which conditions are favorable for them to be chemically linked into longer molecules with enhanced liquid crystal-forming tendencies, he said.

“We found that even tiny fragments of double helix DNA can spontaneously self-assemble into columns that contain many molecules,” Clark said. “Our vision is that from the collection of ancient molecules, short RNA pieces or some structurally related precursor emerged as the molecular fragments most capable of condensing into liquid crystal droplets, selectively developing into long molecules.”

Liquid crystals — organic materials related to soap that exhibit both solid and liquid properties — are commonly used for information displays in computers, flat-panel televisions, cell phones, calculators and watches. Most liquid crystal phase molecules are rod-shaped and have the ability to spontaneously form large domains of a common orientation, which makes them particularly sensitive to stimuli like changes in temperature or applied voltage.

RNA and DNA are chain-like polymers with side groups known as nucleotides, or bases, that selectively adhere only to specific bases on a second chain. Matching, or complementary base sequences enable the chains to pair up and form the widely recognized double helix structure. Genetic information is encoded in sequences of thousands to millions of bases along the chains, which can be microns to millimeters in length.

Such DNA polynucleotides had previously been shown to organize into liquid crystal phases in which the chains spontaneously oriented parallel to each other, he said. Researchers understand the liquid crystal organization to be a result of DNA’s elongated molecular shape, making parallel alignment easier, much like spaghetti thrown in a box and shaken would be prone to line up in parallel, Clark said.

A paper on the subject was published in the Nov. 23 issue of Science. The paper was authored by Clark, Michi Nakata and Christopher Jones from CU-Boulder, Giuliano Zanchetta and Tommaso Bellini of the University of Milan, Brandon Chapman and Ronald Pindak of Brookhaven National Laboratory and Julie Cross of Argonne National Laboratory. Nakata died in September 2006.

The CU-Boulder and University of Milan team began a series of experiments to see how short the DNA segments could be and still show liquid crystal ordering, said Clark. The team found that even a DNA segment as short as six bases, when paired with a complementary segment that together measured just two nanometers long and two nanometers in diameter, could still assemble itself into the liquid crystal phases, in spite of having almost no elongation in shape.

Structural analysis of the liquid crystal phases showed that they appeared because such short DNA duplex pairs were able to stick together “end-to-end,” forming rod-shaped aggregates that could then behave like much longer segments of DNA. The sticking was a result of small, oily patches found on the ends of the short DNA segments that help them adhere to each other in a reversible way — much like magnetic buttons — as they expelled water in between them, Clark said.

A key characterization technique employed was X-ray microbeam diffraction combined with in-situ optical microscopy, carried out with researchers from Argonne and Brookhaven National Laboratories. The team using a machine called the Argonne Advanced Photon Source synchrotron that enabled probing of the “nano DNA” molecular organization in single liquid crystal orientation domains only a few microns in size. The experiments provided direct evidence for the columnar stacking of the nano DNA pieces in a fluid liquid crystal phase.

“The key observation with respect to early life is that this aggregation of nano DNA strands is possible only if they form duplexes,” Clark said. “In a sample of chains in which the bases don’t match and the chains can’t form helical duplexes, we did not observe liquid crystal ordering.”

Subsequent tests by the team involved mixed solutions of complementary and noncomplementary DNA segments, said Clark. The results indicated that essentially all of the complementary DNA bits condensed out in the form of liquid crystal droplets, physically separating them from the noncomplementary DNA segments.

“We found this to be a remarkable result,” Clark said. “It means that small molecules with the ability to pair up the right way can seek each other out and collect together into drops that are internally self-organized to facilitate the growth of larger pairable molecules.

“In essence, the liquid crystal phase condensation selects the appropriate molecular components, and with the right chemistry would evolve larger molecules tuned to stabilize the liquid crystal phase. If this is correct, the linear polymer shape of DNA itself is a vestige of formation by liquid crystal order.”

Symptoms of Mesothelioma of the Lungs

noreply@blogger.com (life hacker) — Wed, 06 Jan 2010 08:38:00 +0000

Mesothelioma of the lungs is called pleural mesothelioma. Symptoms of mesothelioma may not appear for 20 to 40 years after exposure and sometimes longer. Around 3000 people are diagnosed with malignant mesothelioma each year. Roughly 2/3 of mesothelioma cases are Pleural mesothelioma. Pleural mesothelioma occurs in the lining of the lungs called the pleural membrane.

Pleural mesothelioma is caused by the inhalation of asbestos fibers. Once the asbestos fibers are brought into the lungs, they find their way to the pleural membrane. Over time, typically 20 years and more, the accumulation of these fibers begins to scare the lining of the lungs. The scaring causes tumor growth on the lungs and ultimately cancer. The cancerous cells prevent the creation of healthy cells and ultimately the pleural member thickens. As a result, lung capacity is reduced and fluid begins to fill between the pleural layers.

Symptoms of mesothelioma of the lungs (Pleural Mesothelioma) include:

Dry or raspy cough
Night sweats
Fever
Unexplained weight loss (10% or more)
Difficulty in swallowing
Fatigue
Persistent pain in the chest
Painful breathing
Coughing up blood
Wheezing
Shortness of breath (even during rest)
Lumps under the skin on the chest

Mesothelioma: Facts about Mesothelioma

noreply@blogger.com (life hacker) — Wed, 06 Jan 2010 08:30:00 +0000

Mesothelioma is a form of cancer that affects the mesothelial cells of the body. These are the cells that make up the outer lining for the body’s major organs, such as the heart, lungs and stomach. These linings are referred to as the mesothelium and this is how the cancer got its name.

Pleural Mesothelioma

The pleura are the tissue that covers and lines the lungs. These are referred to by the medical community as pleural membranes. The pleura are fibrous membranes and the space between them is the pleural space. The pleural protect the lungs by producing a lubricant that fills the pleural space. This lubricant also allows the lungs to move easily within the chest cavity as we inhale and exhale.

Pleural mesothelioma is the most common type of the disease. Since the lungs are so close to the heart, it is almost always affected. The pericardium is the lining found on the outside of the heart and allows it to move freely within the heart cavity.

The Peritoneum

The peritoneum is the tissue lining the abdomen. Its job is to protect the abdomen’s contents. It produces a fluid that acts as a lubricant so organs within the abdomen may move freely. Peritoneal mesothelioma is cancer of the tissue that lines the abdominal cavity. This form of mesothelioma is rarer than pleural mesothelioma.

Causes of Mesothelioma

Mesothelioma is caused by unprotected exposure to asbestos and affects those who were put at risk for the last 50 years.

Who Gets Mesothelioma

The disease is most common in males who are between the ages of 60 and 70 years old. These men were constantly exposed to asbestos dust and fiber, which caused the mutation of the mesothelioma cells. Mesothelioma takes years to develop, which means early diagnosis is almost impossible.

Others at risk for mesothelioma are those who lived in the same household with someone who was constantly exposed to asbestos. Men carried asbestos dust and fibers into their homes on clothing. It was then breathed in by family members. This put them at risk of contacting mesothelioma and other diseases related to asbestos years after the fact.

Treatment

The success of treatment for mesothelioma isn”t high. The final stages of the disease are fatal. The earlier mesothelioma is diagnosed, the better the prognosis. If you or a member of your immediate family has ever been constantly exposed to asbestos in the workplace, be sure to contact your health care professional to find out exactly what your options are. You may be tested for the disease and get a clear bill of health.

Science committee says NHS must embrace genomic medicine

noreply@blogger.com (life hacker) — Wed, 06 Jan 2010 08:21:00 +0000

The government should bring forward new legislation on genomic medicine, the House of Lords Science and Technology Committee has said.

The committee have published a report on Genomic Medicine which argues that recent developments in genomic science stemming from the sequencing of the human genome represent a unique opportunity for real advances in medical care.

They said the Government should produce a White Paper on genomic medicine and the NHS must take a range of steps to ensure that these advances are realised.

The last White Paper on the issue was published in 2003 and dealt mainly with the diagnosis and management of rare single-gene disorders.

The potential impact of “genomic medicine” has moved on significantly since then and now has implications for patient care across the NHS and a range of common, genetically complex diseases such as diabetes, heart disease and cancer.

Lord Patel, who chaired the Inquiry, said:

“Genomic medicine will clearly have a huge impact on health provision and the NHS in particular over the next few years. It is an ever developing technology that presents both challenges and exciting opportunities for health care.

“The Government must now take the lead on this issue and produce a new White Paper on genomic medicine. It has been six years since the last one and in this area times move on very quickly.

“It is time for a comprehensive statement from the Government on how genomic medicine will be incorporated into the NHS, including details of the extra training doctors and nurses will need in this area.

“We have concerns about the growth of ‘at home’ Direct to Consumer Tests.

“Without proper qualified interpretation results of genetic and genomic tests could cause people to worry unnecessarily and place new demands on NHS services.

“It is time firms offering these tests were required to provide counselling and guidance on interpreting the raw results they provide.”

A range of genetic tests are already being used within the NHS to improve the diagnosis and treatment of a range of common illnesses, the committee said.

However there are several barriers to the translation of new tests from invention through to use within the NHS.

To alleviate these problems, the Committee recommends that the National Institute for Health Research ring-fence funding through a Health Technology Assessment programme to fund research into the use of genomic tests within the NHS, and that the Office for Strategic Coordination of Health Research should be tasked with outlining a strategic vision to overcome the translational barriers identified.

The report also recommends that the Government push for the re-classification of genetic tests within European law from ‘low’ to ‘medium’ risk to ensure that all tests are subject to pre-market review to prove their effectiveness before they are available for use either by the NHS or directly by consumers.

The Committee looks specifically at the growing market for Direct to Consumer Tests (DCTs) and raises concerns about the effect of consumers receiving DCT results via the internet without proper medical advice to put those results in context.

They also point out that because most companies that offer DCTs are based abroad the Advertising Standards Agency has no power to police bogus claims made by DCT providers for their products.

To counter these problems the Committee supports the Human Genetics Commissions work to develop a voluntary code of practice for DCT providers.

The code of practice should require firms to publish details of the effectiveness of the tests they offer. It should also include guidelines for the provision of appropriate pre- and post test counselling to help consumers interpret the results of DCTs.

The Committee found significant inequalities in the provision of genetic services across the NHS, for investigation and management of both rare and common diseases, due to the lack of a national policy on commissioning of genetics services.

Significant changes to the operational systems within the NHS are vital to ensure that an equitable and cost effective service is provided across the country including the need to consolidate laboratory services.

The report recognises that there are privacy concerns about the retention and use of genetic data as well as apprehension about how the data may be used by, for example the insurance industry.

To alleviate privacy concerns the Committee recommends that the Information Commissioner should publish a set of clear guidelines for researchers handling genetic data.

The Committee suggests the Government should work with the Association of British Insurers to draw up a new agreement on the use of genetic tests results for insurance purposes beyond the current moratorium which runs out in 2014.

DNA analysed from early European

noreply@blogger.com (life hacker) — Sat, 02 Jan 2010 20:27:00 +0000

The DNA comes from the skeleton of a male in his twenties

By Paul Rincon
Science reporter, BBC News

Scientists have analysed DNA extracted from the remains of a 30,000-year-old European hunter-gatherer.

Studying the DNA of long-dead humans can open up a window into the evolution of our species (Homo sapiens).

But previous studies of this kind have been hampered by scientists' inability to distinguish between the ancient human DNA and modern contamination.

In Current Biology journal, a German-Russian team details how it was possible to overcome this hurdle.

Svante Paabo, from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and colleagues used the latest DNA sequencing techniques to study genetic information from human remains unearthed in 1954 at Kostenki, Russia.

Excavations at Kostenki, on the banks of the river Don in southern Russia, have yielded large concentrations of archaeological finds from the Palaeolithic (roughly 40,000 years ago to 10,000 years ago). Some of the finds date back as far as 45,000 years.

The ironic thing is that our group has been one of those that raised this issue

Professor Svante Paabo, Max Planck Institue

The DNA analysed in this study comes from a male aged 20-25 who was deliberately buried in an oval pit some 30,000 years ago.

Known as the Markina Gora skeleton, it was found lying in a crouched position with fists reaching upwards and a face orientated down towards the dirt. The bones were covered in a pigment called red ochre, thought to have been used in prehistoric funeral rites.

The type of DNA extracted and analysed is that stored in mitochondria - the "powerhouses" of cells. This mitochondrial DNA (mtDNA) is passed down from a mother to her offspring, providing a unique record of maternal inheritance.

Using technology pioneered in the study of DNA from Neanderthal bones, they were able to distinguish between ancient genetic material from the Kostenki male and contamination from modern people who handled the bones, or whose DNA reached the remains by some other means.

The ancient skeleton was unearthed in 1954 at Kostenki in Russia (Courtesy of Vladimir Gorodnyanskiy)

The new approach, developed by Professor Paabo and his colleagues, exploits three features which tend to distinguish ancient DNA from modern contamination. One of these is size; fragments of ancient DNA are often shorter than those from modern sources.

Previous ancient DNA studies used the widespread polymerase chain reaction (PCR) technology. PCR amplifies a few pieces of genetic material, generating thousands to millions of copies of a sequence. But the researchers found many fragments of ancient DNA were too small to be amplified by PCR.

A second characteristic of ancient DNA was its tendency to show particular changes, or mutations, in the genetic sequence at the ends of DNA molecules.

A third feature was a characteristic breakage of molecules at particular positions in the DNA strand.

Trust issues

The apparent ease with which modern DNA can infiltrate ancient remains has led many researchers to doubt even those studies employing the most rigorous methods to weed out contamination by modern genetic material.

"The ironic thing is that our group has been one of those that raised this issue," Professor Paabo told BBC News.

"To take animal studies on cave bears, for example, if we use PCR primers specific for human DNA on cave bear bones, we can retrieve modern human DNA on almost every one. That has made me think: 'how can I trust anything on this'."

Large concentrations of Palaeolithic finds have come from Kostenki

Using the new techniques, the researchers were able to sequence the entire mitochondrial genome of the Markina Gora individual.

Future studies like the one in Current Biology could help shed light on whether the humans living in Europe 30,000 years ago are the direct ancestors of modern populations or whether they were replaced by immigrants who introduced farming to the continent several thousand years ago.

The modern gene pool contains a wide variety of mtDNA lineages. Studying these maternal lineages provides scientists with clues to the origins and histories of human populations.

Scientists look for known genetic signatures in order to classify an individual's mtDNA into different types, or "haplogroups". These haplogroups represent major branches on the family tree of Homo sapiens.

Early arrival

The researchers were able to assign the Kostenki individual to haplogroup "U2", which is relatively uncommon among modern populations.

U2 appears to be scattered at low frequencies in populations from South and Western Asia, Europe and North Africa.

Despite its rarity, the very presence of this haplogroup in today's Europeans suggests some continuity between Palaeolithic hunters and the continent's present-day inhabitants, argue the authors of the latest study.

Distinguishing ancient DNA from modern has been difficult until now

U2, along with closely related haplogroups such as U5, are among those which could plausibly have arrived in Europe during the Palaeolithic.

Geneticists use well-established techniques to "date" particular genetic events, such as when a haplogroup first diversified. The "U" branch (comprising haplogroups U1, U2, U3 and so on) appears to be more ancient than many other genetic lineages found in Europe.

A recent study found a very high percentage of U types in the skeletal remains of ancient hunter-gatherers from Central Europe compared with later farming immigrants and modern people from the region.

Meanwhile, an analysis last year of mtDNA from 28,000-year-old remains unearthed at Paglicci Cave in Italy showed this individual belonged to haplogroup "H" - the most common type found in modern Europeans.

RNA polymerase

noreply@blogger.com (life hacker) — Sun, 27 Dec 2009 22:51:00 +0000

RNA polymerase (RNAP or RNApol) is an enzyme that produces RNA. In cells, RNAP is needed for constructing RNA chains from DNA genes as templates, a process called transcription. RNA polymerase enzymes are essential to life and are found in all organisms and many viruses. In chemical terms, RNAP is a nucleotidyl transferase that polymerizes ribonucleotides at the 3' end of an RNA transcript.Products of RNAP include:• Messenger RNA (mRNA)—template for the synthesis of proteins by ribosomes. • Non-coding RNA or "RNA genes"—a broad class of genes that encode RNA that is not translated into protein. The most prominent examples of RNA genes are transfer RNA (tRNA) and ribosomal RNA (rRNA), both of which are involved in the process of translation. However, since the late 1990s, many new RNA genes have been found, and thus RNA genes may play a much more significant role than previously thought. o Transfer RNA (tRNA)—transfers specific amino acids to growing polypeptide chains at the ribosomal site of protein synthesis during translation o Ribosomal RNA (rRNA)—a component of ribosomes o Micro RNA—regulates gene activity o Catalytic RNA (Ribozyme)—enzymatically active RNA molecules RNAP accomplishes de novo synthesis. It is able to do this because specific interactions with the initiating nucleotide hold RNAP rigidly in place, facilitating chemical attack on the incoming nucleotide. Such specific interactions explain why RNAP prefers to start transcripts with ATP In contrast to DNA polymerase, RNAP includes helicase activity, therefore no separate enzyme is needed to unwind DNA.

Symptoms of Pancreatic Cancer

noreply@blogger.com (life hacker) — Sat, 26 Dec 2009 12:20:00 +0000

What is the Pancreas?

Pancreatic cancer symptoms can vary based on what part of the pancreas is affected and if it has spread. The pancreas is a gland about 6 inches long that is shaped like a thin pear lying on its side. The wider end of the pancreas is called the head, the middle section is called the body, and the narrow end is called the tail. The pancreas lies behind the stomach and in front of the spine. It cannot be felt during a physical exam exam and is located behind other organs like the stomach, liver, spleen, gallbladder, and small intestine.

Pancreatic Cancer Symptoms Below you will find some of the most common pancreatic cancer symptoms:

Yellowing of the Skin and Eyes. Jaundice, a condition marked by the yellowing of the skin and eyes commonly occurs in people pancreatic cancer. It occurs when an increased level of bilirubin is in the blood. This can occur when a tumor completely or partially blocks bile ducts, slowing the flow of bile.

Abdominal Pain. Abdominal pain is common symptom of pancreatic cancer. It usually occurs on the upper abdomen and may even radiate to the back. Abdominal pain may worsen when lying down or 3 to 4 hours after eating.
Unintended Weight Loss. While losing weight without trying may welcomed by many, but it can indicate something is wrong. Again, unintended weight loss is a common symptom of pancreatic cancer and one that is usually one of the first symptom experienced along with abdominal pain. Weight loss is common in many types of cancer and other benign conditions.

Nausea/Vomiting. Again, another vague symptom of pancreatic cancer that is common among many other conditions. Non-specific symptoms, like nausea, often result in a delay in a pancreatic cancer diagnosis.

Loss of Appetite. Appetite loss is a symptom of hundreds of diseases and conditions, including pancreatic cancer. It can signal something severe or even be related to something as small as a stomach virus. When symptoms are vague like this, medical tests are necessary to make an accurate diagnosis.

Itchy Skin. Itchy skin is a less common symptom of pancreatic cancer. Again, a vague symptom, but when coupled with another symptom like abdominal pain or jaundice, it can be significant in making a more accurate, timely diagnosis. Unfortunately, when someone with undiagnosed pancreatic cancer is experiencing itchy skin, it is often misdiagnosed as a dermatological condition.

Unexpected Onset of Diabetes. In some cases, pancreatic cancer may impede the pancreas' ability to produce insulin, resulting in diabetes. It is important note that most people develop diabetes because of reasons unrelated to pancreatic cancer.

Changes in Stool and Urine Color. Urine may become much darker, while stools loser their brown color, becoming a pale, clay color. This is often due to the bile duct being blocked. Stools can also have a odd, strong smell. Unsure of what your symptoms may be? Try the Symptom Checker to see what your symptoms could mean.

In this excerpt, provided by UpToDate-- an electronic resource used by many patients and their doctors looking for in-depth medical information-- you can see how the location of a tumor can impact symptoms a person may experience:

"Symptoms vary depending upon where the pancreatic cancer is located. Cancers that develop in the head of the pancreas tend to block the drainage of bile from the liver to the intestines and typically cause jaundice. In contrast, tumors that arise in the body or tail are less likely to cause jaundice and more often cause abdominal pain, weight loss, and diarrhea."

What to Do If You Have Pancreatic Cancer Symptoms

If you are experiencing any of the symptoms of pancreatic cancer, see your doctor. Even if they are not related to pancreatic cancer in the end, they are symptoms that do warrant a medical evaluation. More than likely, you do not have pancreatic cancer. You should know that pancreatic cancer is rare -- only 38,000 new cases of pancreatic cancer were diagnosed in 2008.

Is Pancreatic Cancer Screening Available?

Pancreatic cancer screening programs are available, but are not recommended for everyone. It is a rare disease, so there is no need to screen the general population. However, some people with a family history of pancreatic cancer and certain genetic syndromes are at a heightened risk of pancreatic cancer. Those at an increased risk may benefit from specialized pancreatic cancer screening.

Many major research hospitals maintain familial pancreatic cancer registries that study the causes of pancreatic cancer. Registrants are those with a family history of pancreatic cancer or those who suffer from a genetic syndrome that increases their risk of developing the disease. Participants may qualify for annual screenings and other medically relevant benefits. This, however, does not replace routine medical care with your primary care physician. To learn more about pancreatic cancer registries in your area.

Lung Cancer

noreply@blogger.com (life hacker) — Sat, 26 Dec 2009 10:57:00 +0000

Lung cancer starts when abnormal cells grow out of control in the lung. They can invade nearby tissues and form tumors. Lung cancer can start anywhere in the lungs and affect any part of the respiratory system.

The cancer cells can spread, or metastasize, to the lymph nodes and other parts of the body.

Cancer of the lung, like all cancers, results from an abnormality in the body's basic unit of life, the cell. Normally, the body maintains a system of checks and balances on cell growth so that cells divide to produce new cells only when needed. Disruption of this system of checks and balances on cell growth results in an uncontrolled division and proliferation of cells that eventually forms a mass known as a tumor.

Tumors can be benign or malignant; when we speak of "cancer," we refer to those tumors that are considered malignant. Benign tumors can usually be removed and do not spread to other parts of the body. Malignant tumors, on the other hand, grow aggressively and invade other tissues of the body, allowing entry of tumor cells into the bloodstream or lymphatic system and then to other sites in the body. This process of spread is termed metastasis; the areas of tumor growth at these distant sites are called metastases. Since lung cancer tends to spread or metastasize very early in its course, it is a very life-threatening cancer and one of the most difficult cancers to treat. While lung cancer can spread to any organ in the body, certain organs -- particularly the adrenal glands, liver, brain, and bone -- are the most common sites for lung-cancer metastasis.

Symptoms of Mesothelioma

noreply@blogger.com (life hacker) — Sat, 19 Dec 2009 14:04:00 +0000

The most common symptoms of this cancer are shortness of breath, chest pains, weight loss, malaise, and loss of energy. Peritoneal mesothelioma symptoms include abdominal discomfort and Swelling or lumps in the abdomen. Pleural mesothelioma symptoms include pain under the rib cage and a cough that typically does not produce phlegm.

Because these symptoms are common to many illnesses, patients are often misdiagnosed. Most doctors have little or no experience with mesothelioma, so patients often go through a series of tests and referrals to other doctors before an accurate diagnosis is reached. An unfortunate characteristic of this cancer is that doctors may perceive early symptoms - mild and nonspecific - as minor ailments, rather than a more serious asbestos-related cancer. In fact it is often over six months between the first symptoms of disease and diagnosis of mesothelioma.

Dysphagia – difficulty in swallowing – is also a symptom of pleural mesothelioma, but usually in the more advanced stages. Unlike cancer of the esophagus or lungs, it is rare for mesothelioma patients to spit up blood or to have swollen lymph glands.

People with peritoneal mesothelioma generally display one of two patterns of symptoms when they seek medical care: (1) abdominal pain, usually localized and related to a dominant tumor mass with little or no ascites, or (2) without abdominal pain, but with ascites and abdominal distention.

If a patient doesn’t show these symptoms, he or she may fail to complain to the doctor and the doctor may not do a detailed examination that could unearth the cancer. This is one reason mesothelioma is so tough – it’s often there but undiagnosed for years.

More typical cancer symptoms show up only at an advanced stage in mesothelioma, at which time valuable treatment time has been lost.

Malignant mesothelioma occurs almost exclusively in individuals who have had environmental contact with asbestos, and onset of symptoms can occur decades after exposure. Doctors who suspect mesothelioma may request a history of the patient’s worklife, with a particular emphasis on asbestos exposure, and anyone who worked with asbestos in the past should make his doctor aware of that history.

Given the low incidence of this cancer, most doctors have little experience with it, and will usually refer patients to specialized centers. Mesothelioma Aid can help you find cancer centers and specialists, and we can also help you find clinical trials for new treatments.

Mesothelioma Death Rates in Northeast England at Record Levels

noreply@blogger.com (life hacker) — Sat, 19 Dec 2009 13:58:00 +0000

The total number of workers in the northeast section of England who are suffering from mesothelioma has reached the highest levels yet recorded. Worse still, an extensive research report of the British government's Health and Safety Executive (HSE) office states that the number of people in the region to be diagnosed with the disease is not due to reach its full height until the year 2016.

The study results imply that workers in the industrial region will continue to be treated for the disease, which affects the fluid surrounding the lungs, for years to come. Mesothelioma is a rare and often fatal form of cancer that frequently arises from long-term exposure to asbestos fibers. Patients with the disease often die within eighteen months of receiving the diagnosis. With incidences of mesothelioma on the rise, the HSE is treating the situation as a regional and national health crisis.

Investigators at the HSE have predicted that the number of mesothelioma cases will continue to increase for at least another seven years. Reports show a total of 2,046 men died due to mesothelioma in 2005 and 2,058 in 2006, with a sharp increase to 2,156 in 2007. Results from the study also examined the frequency of incidence among females; since jobs that require exposure to asbestos are in male-dominated sectors such as construction, demolition and mining, male patients had an incidence rate five times higher than their female co-workers.

However, the death rate for females rose at a much steeper rate. From 2002 to 2004, the death rate from malignant mesothelioma among females was 11.19 per million, compared to 87.08 per million among males. From 2005 to 2007, the death rate from mesothelioma among females jumped to 16.41 per million, an increase of over forty-six percent from the previous three years. The death rate among males during the same time period was 89.52 per million, an increase of less than three percent.

During the 1950s and 1960s, northeastern England was an industrial center, with numerous facilities specializing in coal mining and shipbuilding. Many of these facilities used asbestos in manufacturing and mining processes. Although women did not typically work in these areas at the time, the theory is that many of the women who contracted the disease did so by being exposed to asbestos fibers that clung to the male worker's clothing.

An HSE representative asserted that asbestos exposure for workers in the area was not simply a problem of the past, but still poses a serious health threat to modern workers. Although the British government instituted a total ban on asbestos-containing materials in 2000, at least half a million foreign-owned facilities in Britain still contain asbestos at varying levels. According to the HSE spokesman, asbestos "is Britain's biggest industrial killer".

One of they key initiatives that the HSE office is likely to start is an asbestos education program for both the workers on the ground and the supervisors and managers of the affected facilities. Agency officials also warned that they would step up efforts to prosecute firms that did not follow strict guidelines in cleaning up and disposing of the toxic material, including providing workers with protective clothing and breathing masks, as well as minimizing the danger of exposure to the general public.

Sources: The Northern Echo, FMWorld

Mesothelioma

noreply@blogger.com (life hacker) — Sat, 19 Dec 2009 13:56:00 +0000

What is Mesothelioma? Mesothelioma from the (Greek meso+ thelioma, tumor of middle lining tissue) is an uncommon cancer, originating from the cells which form the membrane lining the abdominal cavity (peritoneal membrane or peritoneum) which houses the intestines, or the chest (pleural membrane or pleura) cavity housing the heart and lungs, in which the cells making up those tissues begin to grow out of control.

Mesotheliomas most often are seen in older patients, more often men that have a history of occupational exposure to asbestos, although other causes such as radiation and certain viruses have occasionally been implicated. In a proportion of cases, no asbestos exposure can be identified.

Mesotheliomas involving the lung and pleura characteristically present as progressive shortness of breath due to the thickening of the lining membrane of the lung with gradual contraction of the breathing space; often, fluid accumulates in the lung spaces as well, further interfering with breathing, Mesotheliomas involving the abdominal cavity present with digestive symptoms, and abdominal swelling due to thickening of the lining membranes of the gut, and accumulation of large amounts of fluid in the abdomen.

How serious is it ? Mesotheliomas are serious and potentially life-threatening. Survival of patients with mesothelioma is usually short if effective treatment is not found, especially those with tumors that can be shown to be growing aggressively. Because mesotheliomas have usually spread throughout the pleural or peritoneal cavity before the diagnosis is made, complete surgical removal is only rarely possible. Moreover, mesotheliomas are not as sensitive to radiation therapy or chemotherapy as are many other tumors.

How are mesotheliomas diagnosed? In all cases, the diagnosis of mesothelioma must first be unquestionably established by biopsy of affected or suspicious tissues, and by definitive microscopic examination by a trained pathologist. Biopsy almost always requires an invasive procedure such as thoracoscopy and pleural biopsy, or laparotomy or laparoscopy, The removed tissues may be treated with special biological or chemical stains which are used to help the pathologist establish a firm diagnosis. The pathologist usually also comments upon the rate of growth and biological virulence of the tumor

Second, the tumor must be staged if possible by X-ray, CAT scan, MRI or other types of scans to clarify its location within the body, and to estimate the likelihood of effective curative or palliative therapy. Staging of mesothelioma by x-ray measurements, however, is difficult and often unreliable.

How are mesotheliomas treated? A treatment plan is devised depending upon the mesothelioma type, aggressiveness, primary location, and degree of local (rarely, distant) spread. The treatment of pleural mesothelioma is difficult. Treatment with surgery, radiation therapy or chemotherapy used alone or in combination may be proposed, depending upon the potential benefits and risks of each modality. Surgery is rarely used alone, but sometimes suffices when only a small pleural patch of mesothelioma is detected, thus allowing visually complete removal of the tumor. More often, mesotheliomas of the left or right pleural cavity cannot be completely removed without taking the entire lung (pneumonectomy) on the same side as well. In such cases, radiation therapy and/or chemotherapy is given postoperatively to help eradicate any residual mesothelioma that may have escaped the surgeon.

The treatment of peritoneal mesotheliomas is even more problematic; until recently no consistent treatment was available. At our institution, peritoneal mesotheliomas have been managed in the experimental setting with combined modality treatment consisting of extensive (usually not complete) debulking surgery, followed by intraperitoneal and systemic chemotherapy followed in turn by whole abdominal radiation therapy.

Because mesotheliomas now represent less than one percent of cancers and and are infrequently seen in the practice of most community oncologists, finding the correct treatment can be very difficult. Proper management of mesotheliomas often requires evaluation at larger tertiary hospitals or Comprehensive Cancer Centers by specialists in medical, surgical and radiation oncology with experience in all aspects of the clinical care of mesothelioma patients, including the newest experimental treatments.

What Does DNA Stand For?

noreply@blogger.com (life hacker) — Sat, 19 Dec 2009 13:49:00 +0000

DNA, the acronym for Deoxyribonucleic Acid, stands for the key foundation on which the structure of life is built. It is the set of instructions contained within the DNA and the difference in these instructions from one DNA to the other that results in one human being different from the other. The difference that we are talking about here is not only in terms of different hair color and facial features but that these human beings even differ in the way they react to the same situation and same environment.

It is very interesting to note that although each cell of human body holds the same DNA, the structures of different parts of body even though based on this same DNA are very different. Modern biology has found out that this is due to the fact that different areas of DNA are active in different parts of the body. That’s why DNA in blood cells produces what is required for the blood and DNA in muscle cells build proteins that are needed by muscles.

DNA stands for the progression and advancement in modern day biotechnology. Nowadays biotechnology industry has become a lucrative business. There are many firms studying and synthesizing DNA all around the world from Washington D.C. to Tehran and Hong Kong for example.

Developments in biology and especially genetic studies have pretty much answered the question of “What does DNA stand for?”. Thanks to James Watson and Francis Crick, it’s already more than 50 years that the structure of DNA was explained in precise detail.

However, not all that DNA stands for is good. DNA has changed the concept of security and defense for a country because of the dangers it faces from the development of biological weapons. These biological weapons, based on DNA technology, can be exploited to not only paralyze but also demoralize a nation by causing a devastating breakout of viral, infectious and untreatable diseases. Many germs of the known and curable diseases have been improvised to become more dangerous and incurable. Dirty bombs are easy to be manufactured with this knowledge, as they do not require high technology or heavy investment. If these bombs ever fall in the wrong hands they can cause a high security risk globally. So all is not fine about DNA’s discovery, we have to be very careful about the ill uses of this technology.

DNA Structure

noreply@blogger.com (life hacker) — Sat, 19 Dec 2009 13:48:00 +0000

Each and every cell of a living organism, be it plants or animals, has DNA. This information-encompassing module is vital for all processes that govern the growth, reproduction, development and maintenance; and is also responsible for the continuation of heredity, an important aspect of our lives.

In 1953 James D Watson and Francis H C Crick were the first who presented the DNA structure, which according to their findings is of double helix nature. To understand the inception of life it is imperative to study the structure of DNA.

An embryo uses DNA and RNA (similar structure as DNA with small difference) instructions to make proteins to transform into an organism. This new organism has all the characteristics of its parents, for this reason a human has a human baby and a plant produces seeds.

DNA and RNA are nucleic acids, which rule the development of embryo and copying of the genetic information. Apart from the role DNA plays in the reproduction and its associated heredity issues, DNA is also responsible for laying out the proper guidelines for the production of proteins that are essential to the appropriate functioning of our body.

Trying to understand the structure of DNA may seem like a daunting task initially. However, that’s not the case and the basic DNA structure can be explained very easily.

It’s all based on four nucleotides that show up again and again in a long chain. The particular order, in which they show up, sets the properties or traits of a cell and differentiates one chain from the others.

Moreover, DNA is like two strands coiled together; this property is called double helix and is antiparallel (one of the strands is basically reversed).

These DNA strands are made up of sugar, phosphate and nitrogenous bases. The former actually build the strand part while two of the nitrogenous bases pair up and form the middle part. All in all, there are four nitrogenous bases, which are, Adenine, Cytosine, Guanine and Thymine. For convenience purposes, they are mostly referred to as A, C, G & T in DNA studies.

The nitrogenous bases are categorized into two classes of purines and pyrimidines. A & G belong to the purine class while C & T belong to the pyrimidine class. The bases always pair in the form of A with T and C with G. Any other pair will not work out. Weak hydrogen bondings keep these bases together.

DNA Genealogy

noreply@blogger.com (life hacker) — Sat, 19 Dec 2009 10:09:00 +0000

Genealogy is the study of pedigrees. DNA is an essential ingredient of it, though it can’t be used for genealogical analysis without taking into account of the conventional basis of family history, i.e. oral and documental history. With the accessibility of these customary resources, in addition to the DNA genealogy testing, one can disclose the deep-rooted relations and can solve many legends.

Scientists and family historians have developed several types of tests centered on DNA Genealogy and depending upon the aim of the research a suitable test is selected. The two major tests for DNA genealogy analysis are based on Y-chromosome and the mitochondria.

Y-chromosomes get transferred from father to his sons, from them to his male grandchildren etc. In mitochondrial DNA, a female transfers her DNA to all of her children but then only her daughter will pass that DNA to the next generation.

In Y-chromosomes DNA, determining the haplogroup and haplotype of the testee are key measurements. In this test, specific sections of Y-chromosomes are scrutinized for certain chemical indicators. Haplogroup indicator doesn’t vary in due course but the other indicator varies regularly. These two indicators establish the genetical mark of a person.

With the advancement of DNA genealogy knowledge, many relationship tests have emerged. They are basically done for finding out facts related to paternity, maternity, forensic, grand parentage, sibling ship and twin pregnancy. These are helpful in social security, legal and immigration cases.

Paternity is done to verify the true father of a child and similarly the maternity test is performed to know the natural mother. Likewise the parentage test establishes the family of a person when the true father is not available and grand parents test to disclose the genetic lineage. To examine and evaluate the oblique relations like aunts, uncles, cousins etc. Genetic reconstruction is done to authenticate a true father if the natural mother is available for the test. On the contrary the expensive sibling test can be conducted without a natural mother to find out whether the persons involved have the same parents. If there are any health concerns in the twins’ pregnancy then twin zygosity test is performed to know whether the twins are fraternal or identical. Forensic test are commonly used in criminal cases.

DNA genealogy also assists in identifying the surnames, their growth and practice. Surname study discloses the irregularities between the present and chronological surnames. It also establishes the existence of any relationship or non-relationship among different people.

DNA Analysis

noreply@blogger.com (life hacker) — Sat, 19 Dec 2009 10:05:00 +0000

When Watson and Crick discovered the double helix structure of DNA and explained their understanding of how it works, it wasn’t for many to realize the grand role that DNA analysis would play in various fields of life.

Today DNA analysis is a full-blown industry. Major projects like Human Genome Project are opening the doors of new research activities and various new applications of DNA analysis are showing up.

One industry where the role of DNA analysis can never be overstressed is the forensic investigation domain. Based on huge DNA profile data banks maintained by different agencies, such as Combined DNA Index System (CODIS) by Federal Bureau of Investigation. DNA evidence found at a crime scene can be compared against DNA profiles of convicts and known offenders, leading to a clue. Paternity disputes and cases can also be solved via DNA testing.

DNA analysis also plays a major role in the area of biosecurity. Diseases that are of infectious nature or pose threat to human population at large can be timely identified by public health organizations and thus taken action against.

DNA Analysis is also used extensively in the field of food testing. Pathogens that are detrimental and pose danger to the supply of food and consequently public health can be detected.

The advancement in DNA analysis technology has led to the development of personalized medicine. A relationship can be established between certain diseases and the way they respond to healing. Hence patients with similar DNA profile can be treated with medicines that are tailored to their DNA profile.

In fact, the role of DNA analysis is so phenomenal in health sciences that it is bringing many revolutions. The study of genomics is not only delivering effective results in safeguarding human health and protection but also aiding the environmental safety activities. Once more cost effective ways of DNA sequencing are worked out, the use of genomic information can be expected to be applied at many more areas in medical research.

DNA analysis has come all the way in identifying genes that are prone to certain diseases. By making use of the latest technology and tools, it will be possible to monitor the probabilities surrounding the genetic variations and how these could be linked to the genes mentioned earlier, thus developing diseases in human beings. The same technology will also be used to develop new ways of handling these diseases, thus obtaining better results from the treatment.

Overall, DNA analysis has done miracles in history and is rightly headed towards more.

DNA Testing

noreply@blogger.com (life hacker) — Sat, 19 Dec 2009 09:56:00 +0000

Where we come from?’ is not only an emotional query but can also be an important question to answer in many legal situations. With the emergence of tools and solutions that make use of converting the scientific and advanced DNA knowledge into practical applications one can use for discovering his or her heredity concerns, the commercial popularity of DNA testing has gone widespread.

DNA testing can be used in a wide variety of cases that range from parentage disputes and child support issues to identifying the genetic illness risks that one child may be carrying. Overall, DNA testing does a wonderful job of resolving issues scientifically and bringing peace of mind in our lives.

In this article, we are going to briefly cover the popular uses of DNA testing.

Paternity establishment is an important issue that can be solved via DNA testing. In layman language, the test will verify the paternity claim that a father has over his son or daughter. Apart from the uses of this test in disputes between couples, it can also be availed by a father to ensure that his offspring enjoys benefits such as Social Security, health insurance etc arising out of this relationship.

The paternity establishment tests, unless required by law enforcement agencies, can also be conducted in the comfort of one’s own house. You just have to follow the simple instructions and return the collecting kit to the commercial DNA testing company. The results will be delivered to you as discreetly as you instruct.

DNA testing can also be employed in the cases for child support. Even if the father of the child is missing, paternity can still be established via testing the DNA samples obtained from both of the grandparents.

Immigration is another area where DNA testing is widely adopted as a replacement of documents that prove biological relationships between family members.

The use of DNA testing in forensic investigations is simply momentous. In fact, the Federal Bureau of Investigation maintains a large database of DNA profiles, which could be referenced by various DNA labs to assist the law enforcement agencies in their search for the crime suspects.

A breakthrough in fight against the inherited diseases is Prenatal DNA Screening. This kind of DNA testing results in the identification of genetic diseases in a developing child. The known diseases or defects can either be prevented or managed depending upon the problem and available solutions.

DNA Research – History

noreply@blogger.com (life hacker) — Sat, 19 Dec 2009 09:54:00 +0000

The history of actively conducting DNA research goes all the way back to 1868, when Friedrich Miescher, a biologist from Sweden, worked out chemical research on the nuclei of cells. Not only did he find out a phosphorous containing material that he called nuclein, but he also pointed out the fact that this material consisted of two portions. One was an acidic segment, which is now known as DNA, while the other part was made up of proteins that packaged DNA.

However, it wasn’t until towards the end of 1940’s that the current picture of DNA emerged as a carrier of genetic information. Scientists working at the Rockefeller Institute, in 1943, based on their experiments concluded that DNA was responsible for transferring of genetic information, but they encountered resistance from other members of the bio community. Alfred Hershey and Martha Chase, in 1952, proved the case through a radioactive isotope tracer experiment.

Though Alfred Hershey’s DNA research had proved the case for DNA as the carrier of genetics information but the structure of this DNA and how it works was still a mystery. It was in 1953 that James Watson, an American genetics scientist, working together with Francis Crick, a physicist from England, came up with the double helix structure of DNA. This was a breakthrough piece in DNA research that has lead to much advancement in the field of genetic sciences. The two scientists also made use of DNA research that other scientists of that period had carried out and combining it with their own findings, they gave a very comprehensive picture of DNA structure.

Helping Watson and Crick build their double helix DNA model was the important DNA research carried out by Erwin Chargaff at Columbia University. Erwin discovered that while different organisms may have diverse proportions of nucleotide bases in their DNA, but the quantity of adenine will always be equal to thymine and guanine to cytosine. This led Watson and Crick to formulate that adenine always pair up with thymine and guanine with cytosine and hence are always present in same quantity.

DNA research has come a long way from these findings of 1950’s. Now things like DNA cloning are happening on commercial grounds. The mysteries of topics like DNA replication, DNA sequencing, DNA mutations etc have been well discovered too and what is left will not take too much time before it gets into human knowledge.

What is DNA and Genealogy

noreply@blogger.com (life hacker) — Sat, 19 Dec 2009 09:52:00 +0000

All humans have 23 pairs of chromosomes, including a pair of sex chromosomes, known as "X" and "Y". Males have both an X- and a Y-chromosome (with the Y-chromosome inherited from the father) while females have two X-chromosomes (one X-chromosome inherited from each parent.) Genetic Genealogy is interested in heritage markers or the area of the chromosome which reveals family relatedness.
Father-to-Son
Because the Y-chromosome is passed essentially unchanged from father-to-son, it provides genetic genealogists with a powerful tool for tracing a paternal lineage. Specific portions of the Y-chromosome are analyzed and compared against other participants' Y results to determine the relatedness between the two participants.
Mother-to-Child
Since both parents contribute X-chromosomes to their daughters, a different source of DNA must be used to trace the maternal line. Mitochondrial DNA (mtDNA) is inherited by both male and female children exclusively from their mothers and provides insight into one's maternal lineage

DNA Polymerase

noreply@blogger.com (life hacker) — Sat, 19 Dec 2009 09:50:00 +0000

The process of DNA replication is made possible by the presence of an enzyme called DNA Polymerase. DNA replication gets started when DNA polymerase binds itself at a primer on one of the two strands of DNA. This single strand of DNA is then taken as the base or guide, often termed as template, and DNA polymerase starts adding extra nucleotides as part of the replication process.

It is important to note that as of yet, genetic biologists do not know of any DNA polymerase that can start a new chain on its own. DNA polymerase always has to depend on an available 3’-OH group for adding the nucleotides.

As mentioned earlier in the article, DNA polymerase always looks for the presence of a primer where it can start adding nucleotides. This primer, which acts like a process starting cue, is composed of RNA and DNA bases and the sequence of these bases always has two RNA bases at the front. Enzymes called primase synthesize these RNA’s while it is the responsibility of helicase enzyme to form a single stranded structure of DNA from its double stranded shape. It’s this new single stranded form that is then used to follow DNA replication process.

Some of the DNA polymerases are intelligent enough to exercise an error correction mechanism, which is a process of rectifying errors in the replicated DNA. In case a wrong pair of base has been formed, the intelligent DNA polymerase recognizes it immediately and reverses the last pair in replication process. This error correction process has also been named as Proofreading. After getting rid of the wrongly paired base, DNA polymerase restarts the replication process by adding a right pair of base nucleotides.

DNA polymerases have been classified as categories called families. These families are:

Family A: It consist of replicative as well as repair DNA polymerases.

Family B: Most of the polymarases in this family are of replicative nature and are known for their outstanding accuracy in the process.

Family C: These are basically bacterial chromosomal enzymes that are used in the replication process.

Family D: This family needs more research activities to be classified properly.

Family X: This family consists of some of the largely known eukaryotic polymerases.

Family Y: An interesting factor regarding DNA polymerases in Family Y is that they can work through damaged DNA and replicate it. However, depending on the circumstances the error can either be escaped or worsened into mutation.

Family RT: These synthesize DNA by making use of an RNA template.

DNA Molecule

noreply@blogger.com (life hacker) — Sat, 19 Dec 2009 09:43:00 +0000

The magnitude of information contained within a single DNA molecule is truly extraordinary and inspiring. Would it ring any bells if you were told that as much of information as contained in the complete series of Encyclopedia Britannica is enclosed in the DNA molecule of E.coli, a bacterium that only consists of a single cell.

For those who are unfamiliar with the structure of DNA molecule, it’s a double stranded chain that resembles a helix. The basic elements building this structure are sugar-phosphate bonds and four chemical bases. These chemical bases are named as Adenine, Thymine, Cytosine and Guanine, often cited as A,T,C & G. Based on the sequence in which these chemical bases show up, each DNA has a different code of instructions for the cell. Going through a lot of intermediary stages and processes, these instructions are finally translated into the different characteristics that parts of our body display as well as the individual traits that become part of our personality.

It’s the abundance of this information and set of codes within the DNA molecule, and the way this information travels through the body to achieve its goal of controlling each and every aspect of body functions, that has astonished biologists and scientists all over the world.

The mystery behind the creation of first ever DNA molecule has not been solved yet. Unfortunately many scientists have gone off the way by trying to explain the origin of DNA molecule on the basis of studying the information it contains. However that’s like trying to explain the existence of a messaging system and channel based on the ‘what and how’ of the message it is sending out.

Scientists that brought up such theories based it on the self-replicative nature of base chemicals in a DNA molecule. The way these bases and other stuff organizes themselves in DNA structure on their own, the way they run a very complicated information system with precise storage and retrieval facilities, they way they are able to replicate their existence and work against any errors in this process, led them to believe that going all the way back to millions of years, self creation of DNA is a possibility. However, this does look illogical on the surface and doesn’t have a solid base to prove its case.

In fact, the underlying structure of DNA molecule and the way information is stored and sent out via an incredibly intelligent mechanism, is forcing many scientists to give up their philosophy of life evolving through arbitrary non-life forces.

What Is DNA Forensics?

noreply@blogger.com (life hacker) — Sat, 19 Dec 2009 09:37:00 +0000

DNA forensics is a special area of expertise within the broader area of forensic science that deals with genetic materials during the investigation of a crime. Those who specialize in DNA forensics assist law enforcement officials by locating evidence in the form of genetic material that can tie suspects to the scene of the crime. DNA forensics can also be used to clear suspects of any involvement in criminal activity.

DNA

Without the discovery of DNA, forensic scientists would never be able to solve thousands of crimes that depend largely on the evidence they can unravel. DNA stands for deoxyribonucleic acid and it contains the building blocks of all life. Vital information is contained within the chromosomes and this information is unique to each individual.

Collection

DNA evidence is collected from crime scenes as well as from suspects after the fact. DNA can be obtained from blood cells, semen, hair follicles and skin samples left behind at the crime scene. Suspects may be required to provide DNA samples against which this evidence is compared. In addition, there are also larges databases filled with DNA information that a computer can scan against collected evidence.

DNA Fingerprinting

DNA has provided the same kind of quantum leap in forensic investigation that fingerprints provided over a century ago. While the chemical structure of DNA is the same for everyone, there are literally millions of differences in the sequence of what is known as base pairs. Using this information, forensic scientists are able to arrive at what they term DNA fingerprinting, which essentially allows them to determine whether two DNA samples come from the same person, people who are related, or people who have no relation to each other.

History

The history of DNA forensics traces only back to the 1980s. British geneticist Alec Jeffreys was the first to proposed the concept of DNA typing as well as DNA fingerprinting. The experiments on the repetition of DNA sequences conducted by Jeffreys revealed a technique that could be used to examine variations between people. From Jeffrey's original tests, modern day DNA forensics was born.

Advances

In the early days of DNA forensics following Jeffrey's breakthroughs, it could take up to six weeks just to derive a conventional DNA profile. Some DNA evidence took even longer to construct. Due to advances in computerized technology, however, digital analysis and categorization of DNA samples can be processed into a DNA profile in just a matter of days.

Paternity Testing

Although the use of DNA forensics gets the most headlines when used to capture murderers and rapists, the most common use of this technology, by far, is for paternity testing. DNA forensic science is capable of determining the father of a child in cases where fatherhood is dispute as well as to either prove or disprove family ties in immigration cases.

DNA Basics

noreply@blogger.com (life hacker) — Sat, 19 Dec 2009 09:33:00 +0000

Genetic Genealogy Overview
What can DNA do for me?
You might already be familiar with how DNA testing can help solve crimes, confirm the paternity of children, and even determine the identity of ancient mummies. Now DNA can also help you with your genealogical research. It's a simple and painless process to gather your DNA sample and within a few weeks have results that you can compare with the ever-expanding Ancestry.com DNA database to find potential genetic cousins. Learn more about the science behind DNA, chromosomes, and genetics.

Finding genetic cousins
By comparing your Ancestry.com DNA test results with others, you can determine to what extent you are related. For example, the more closely your result set matches another's, the narrower the range of generations between the two of you and your common ancestor.

As the Ancestry.com DNA database grows, we will automatically compare your result against each new entry. If a close match is found, you will receive an e-mail with a link to a page that describes how your two test results match. You can now begin communicating with your genetic cousin using Ancestry.com's Connection Service as the first step towards comparing the genealogies of your two families.
Discover ancient ancestry
In addition to finding genetic cousins, your DNA test can also reveal your ancient origins. Beginning over 170,000 years ago, our ancient human ancestors migrated out of Africa and began their slow and steady spread across the continents. Over time as these ancestors spread throughout the world and adapted to their new surroundings and environments, their DNA diversified and they became genetically distinct from one another. Today, these differences can be traced through DNA and provide insights on how your ancient ancestors migrated and diversified into distinct populations.

Why Is DNA Important?

noreply@blogger.com (life hacker) — Sat, 19 Dec 2009 09:10:00 +0000

DNA is the blueprint of biological life from its inception to its growth and till death. Its discovery has not only revolutionized science and medicine but it has affected all walks of life; whether they are social, legal, criminal or inheritance related. DNA’s discovery has become important to the extent that it has even influenced a nation’s security parameters / concerns, as scientists have gone all the way to developing biological weapons.

The simplest answer for “Why Is DNA Important?” is that DNA is the prerequisite for life’s inception. It dictates life in two manners. Firstly, it transfers hereditary information from generation to generation. Secondly, it controls the production of proteins. DNA even determines the structure of the cell, meaning whether it would be a nerve cell or eye cell etc.

Genealogy, i.e. the study of ancestry, depends on the study of DNA. With the help of verbal and written history, and cues from DNA testing, one can trace his ancestors and learn about his family tree. It is so, because of the fact that DNA duplicates itself at cell division (in embryo) and passes on all of its properties to its daughter cells. Thus genetic information gets passed from generation to generation. In this transfer, Y-chromosomes do not change that much with the passage of time, hence it helps in assessing the true father and grandfather and even the whole family tree. This resolves not only social matters but legal and inheritance matters as well. Genealogy is also useful in determining the biological mother and other relatives. It can even tell if two siblings truly share the same parents. Study of DNA in genealogy has also shown its importance in detecting the hereditary diseases and in working out their cure.

When it comes to forensic science and its applications, DNA is an important part of it. It has resulted in many breakthroughs in criminal cases as it can be used to trace the criminals by comparing the DNA samples found on the crime scene with those extracted from the suspects.

DNA’s discovery has proved very important for our agriculture too. Scientists have used this knowledge to improve the food products and crops by genetically modifying them and making them more powerful to fight diseases. This way they have increased the magnitude of agricultural production too. Similar technology has been applied by animal farming industry resulting in improved breeding and stronger built of animals.

What is DNA ?

noreply@blogger.com (life hacker) — Sat, 19 Dec 2009 08:57:00 +0000

In order to truly answer the question of “What is DNA?” one has to go back to the elementary or high school biology classes. You’ll recall that there are elements called chromosomes in each cell of human body. To be more precise, each cell contains 23 pairs of chromosomes. You’ll be astonished to know that some 50 to 100 thousand genes are held within these chromosomes. Since each of these genes could actually take value from one of the two values of its parent cells, hence you can imagine the possible variability in this structure.

These genes are made up of what is called DNA that is Deoxyribose Nucleic Acids. Apart from these genes that carry very essential genetic information and only account for 2% of DNA’s structure, the rest of the 98% of DNA is still a mystery. Biologists actually call it junk DNA as there are no known proteins or traits that are coded or built by this part of DNA. This junk DNA as well as the genetic information carrying part only varies in structure owing to the presence of four nucleotide bases throughout the DNA in differing order and sequence.

Think of these four nucleotide bases in DNA as letters that form an alphabet. Just like the way the order of letters determines the meaning of the word that is formed, the sequence of these nucleotide bases concludes what information is available for the production of proteins that consequently take an active part in the formation and growth of body.

Most of the DNA is present within the nucleus of the cells. This is known as nuclear DNA. Mitochondria also hold modest quantity of DNA, which is termed as mitochondrial DNA. The latter is useful in tests related to someone’s distant maternal lineage.

What is really great about DNA is that it has a very autonomous self-replication mechanism in action. The replication process makes use of the two strands of DNA. Each of these strands acts as template and after going through a series of steps is converted into dual stranded DNA once again. This replication is very important because when the cell divides, the newly formed cell requires the same set of instructions for it to function and grow and the replicated DNA serves this purpose.

Summing up the answer for what is DNA, it could easily be said that it’s a well designed program spanning thousands of lines of codes that has instructions for everything that the cell needs to perform.