DNA Testing: Forensic Paternity Test

DNA or Prenatal testing during pregnancyYou’ve seen this plot on TV shows like Law & Order—a woman mysteriously dies, foul play is suspected, and the autopsy finds the woman is pregnant! A DNA test of the fetus is ordered to find out who the father is, and the results usually help solve the mystery and the crime.

There are many similarities between TV cases and a real life murder mystery playing out in Austin, Texas. The difference here is, no autopsy was needed to reveal the twist of an unknown pregnancy–Samantha Dean was seven months pregnant when she was found dead in her car, shot in the head multiple times.

Ms. Dean was a police department Victim Services Advocate, and had been seeing an Austin police officer socially. He has been placed on restricted duty in connection to the investigation.

DNA testing is the key to solving the mystery of who fathered the baby Ms. Dean was carrying. Both Dr. Michael Baird of DDC and Dr. Vincent Di Maio of Bexar County were interviewed by KXAN of Austin, and each agree—DNA results will be very accurate, and “virtually foolproof.”

Here is where the next steps differ greatly from TV shows, where the DNA results seemingly come back the next day. In a case like this, the DNA will most likely be sent through the county or state DNA lab, and the samples will get in line behind dozens, or hundreds, of other cases. Dr. Vincent Di Maio said the tests could take a few weeks to produce results, if there is a backlog in testing. What can happen to a case while a few weeks goes by? Where is the swift justice for the grieving family?

Dr. Michael Baird of DDC, when interviewed, said, “The DNA tests that we do [take] a matter of days. Our typical turnaround time is two days at DDC.” Private labs often can produce test results much faster than county labs. Counties invest in DNA labs for the right reasons, but when the backlogs create long wait times, law enforcement should have a back-up plan to contract with private labs to avoid lengthy delays and relieve time pressure, to promote timely justice for those in need of answers.

For more information on DDC’s Forensic DNA Testing, click here.

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11 Fathers of Asia: Does DNA Testing Prove 800 Million Men are Descendants of 11?

Researchers suggest Genghis Khan and ten other powerful Asian rulers dating back to 1300 BC share distinctive sequences in Y-chromosomes—part of our DNA that only men carry—with over 800 million men living today. Perhaps as many as 16 million men are directly tied to Genghis Khan himself.

Genghis Khan

Published in the European Journal of Human Genetics and highlighted in a Daily Mail feature on January 28, 2015, the study links prolific leaders in Asia to men living today, by studying the distribution of gene sequences in today’s populations. Researchers analyzed the Y chromosomes of 5,231 men from 127 different populations around Asia. They found 11 common Y chromosome sequences that cropped up repeatedly in the genomes they examined; 37.8 percent of the men tested belonged to one of these 11 lineages.

Geneticists have found lineage clusters, but cannot clearly identify the original individuals unless their remains are found and tested. They believe the only men with the opportunity to father as many children needed to create these large clusters would have been warlords of Mongolia like Genghis Khan 800 years ago.

Writing in the European of Human Genetics, professor Mark Jobling wrote “High reproductive success if often associated with high social status, ‘prestigious’ men having higher intramarital fertility, lower offspring mortality and access to a greater number of wives.”

“If the tomb of leaders like Genghis Khan are ever unearthed, it could result in the ultimate paternity test for millions of men around the world” writes Richard Gray of the Daily Mail. “The only way to know for sure who these 11 founding fathers were will be to find their remains and extract DNA.”

For more information on lineage testing, and paternity testing, contact DNA Diagnostics Center.

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How Long Does it Take to Get DNA Paternity Test Results?

If you’re wondering how long it takes to get the results back from a DNA paternity test, the answer can vary, depending on which lab you choose. While some DNA labs can provide results in 1-2 days, others can take 3-12 weeks or longer! With tax season approaching, many people are looking for paternity results sooner than later to ensure they claim the right number of dependents on tax forms. Whatever your reason may be, there are many options for DNA paternity tests: legal, curiosity, prenatal, post-natal–choose wisely to fit your needs, and your budget.


Why would it take longer to find test results?

If you decide to go through a child support office in your county, you must meet specific criteria for a court ordered DNA test. The time the process takes has come down significantly over the years, but there are still forms to be processed, a court order to be sent down from a judge, coordinating the DNA collection, and more paperwork before results can be released. There is no “RUSH” option during these adoption procedures, so there may be a lengthy wait ahead. Once everything has gone through, the results will become public record, and court admissible.

  • Longest wait: 4-6 weeks and longer, from county Child Support office—if you qualify.
  • Shortest wait: 1-2 days, from private lab—but call first!

How can you get faster paternity test results?

If you contact a DNA lab directly, and hustle in for the DNA collection of all parties, some labs offer a priority turnaround times on results. You could be seeing your results the day after the lab has all the samples and paperwork. Imagine doing the initial call on a Monday with the results on a Friday! The key is to call and talk directly to a testing coordinator and get very specific about what you want, when you want it, and how much it will cost.

Some paternity testing sites offer fast testing, but it may take them a week to mail you the kit, with a week to return it. Make sure when you are shopping around, that fast testing is only part of the picture. Other labs offer a low introductory price, but then layer in “Shipping & Handling” and other fees, making it not so savvy afterall. Make sure you call and ask about all the features, otherwise, you’ll likely be disappointed.

Don’t forget about accuracy! If you get the results fast but aren’t 100% confident in the results, you’ve wasted your money. Before buying, make sure to do your homework on the lab and make sure it is the right choice for such an important test. When you are browsing, look for AABB Accreditation, BBB ratings, and other independent ratings that ensure good practices and accuracy.

To talk to a DDC representative, click here for a list of services and phone numbers.

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How much does a paternity test cost?

Tax Refund Discounts - Legal and Home Paternity DNA testsYou might be wondering if you can afford a high-quality paternity test. There are many companies offering “cheap” paternity tests, and the range of prices that you see, from $79 to nearly $2,000, can be confusing. At DDC the range is smaller, from $189 to $459 (with further discounts often available), depending on the services needed and use of results for legal purposes. This post sheds some light on what goes into paternity testing costs.

Although a DNA test may seem as simple as a pregnancy test, many factors can affect the accuracy of a DNA test result and what you can use the results for. These are the top two considerations when looking at how much a paternity test costs.

First, let’s talk about accuracy. Because DNA testing is a highly sensitive test, careful and precise steps must be taken to ensure the correct result is reported. In our laboratory, two independent teams of DNA analysts run every legal DNA test twice, using state-of-the-art equipment, and the end results are verified by a trained scientist with a PhD degree. We do this above and beyond the AABB requirement, to assure our clients of  100% accurate results.

The second thing to consider is what you eventually will use the test results for. Many people need a paternity test to provide legal documentation of paternity—for child support, child custody, and inheritance, and others.

A legal paternity test provides documentation of the entire testing process, and a trained professional collects the DNA samples from the participants. This type of paternity test costs more, but you can be assured of legally admissible test results should you need them now, or in the future.

On the other hand, if you just want the paternity test results for personal knowledge, a home paternity test allows you to collect the samples conveniently and in private. This type of test costs less, but the results may not be accepted in a court of law. Since this test may not be challenged in court, some companies cut costs on these tests.

If you feel that a company’s DNA testing prices sound too low to be reliable, it’s probably true. You never know what shortcuts a company is taking to drive their costs down. Be smart—the most important test you’ll ever purchase deserves the most trusted laboratory in the world.



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What Makes a DNA Paternity Test Legally Admissible?

Certain things are needed to make your DNA testing legalParents, guardians and custodians of children have good reasons to want to know the legal parents of a child. In some cases, multiple parties might want full or partial custody of a child or visitation rights.

Even when custody is not an issue, the courts must often set financial guidelines for the child’s support. In the case of a severe illness, knowing the ethnic heritage of both parents is important in helping diagnose potential diseases and conditions that can be passed genetically among people of a specific ethnicity.

Whatever your reasons for needing a DNA paternity test, you can save time and money by knowing if your test is legally admissible in court. While different states might have different rules and regulations, knowing the basics of court-recognized DNA tests will help you get the right test you need the first time.

Who Can Request a Test?

Depending on the jurisdiction of your case, people who can request a DNA paternity test include the following:

  • Alleged mother or father
  • Legally recognized mother or father
  • An adult child or a minor child’s representative
  • Legal guardian or custodian
  • Government social services worker
  • Prosecuting attorney

While some people can be legally required to take a paternity DNA test, the person requesting the test must be able to show some relationship between the child and alleged parent. The rules and regulations vary by state.

What is the Process?

Getting a legally admissible DNA paternity test is a three- or four-part process, depending on how you have your test performed. If any one of these steps isn’t handled correctly, the court might not accept your DNA sample.

#1 Collect the DNA sample

An independent, third-party professional must collect a DNA sample for a test to be legally valid in most cases. This is usually done with a cheek swab. The professional must be able to verify you are the person you say you are or the child is who you say he or she is, which requires providing a legally valid ID.

Buying a home-DNA test kit, collecting your own sample and sending it to the company through the mail does not result in a court-recognized DNA test. In some jurisdictions, you might be able to use an independent third party to watch you collect the sample and properly transport it to a legally approved facility. If you’re interested in using a home-DNA test, first learn what the process is for making it legally admissible and what forms everyone will need to sign.

#2 Transport the DNA sample to the lab

Once the sample is collected, a court-approved third party must it is properly shipped to the lab doing the testing. This prevents the third-party collection agent from taking the sample and then giving it to a suing party to take to a lab. This could result in the suing party switching the sample. The process of taking a sample and then transporting it to a testing facility is referred to as chain of custody. Courts look at the chain of custody to determine if the sample was in the possession of acceptable third parties during the period from sample collection to transportation to a lab to actual testing.

#3 Have the sample tested

Once your sample is at the lab, it must be tested. Verify with your counsel or judge that the court will recognize the persons or organizations collecting, transporting and testing your sample. Use caution, even if you “know someone” at a lab who can do a DNA test for you. The facility might not be recognized by the court as acceptable for conducting a paternity test. At a minimum, the lab should be accredited by the AABB.

#4 Send the results to the court for a ruling

Once your test is completed, it must be submitted to the court correctly. If the results are sent to you, you must submit the paperwork provided by the lab. The courts might not accept a photocopy or scan of the documents, so discuss with your attorney whether or not you need original documents. Your best might be to have the lab send the results directly to the court, providing you with a second copy.

Things to Avoid

Don’t proceed without guidance from an attorney, the court, or at least a testing facility that can demonstrate to you that they are recognized by the court to collect to transport and test DNA samples.

Don’t destroy your DNA sample until your case is settled. Opposing attorneys might challenge the validity of a test or ask the court to allow them to use the sample for testing at another facility. Ask the laboratory testing the DNA samples how long they keep samples.

Don’t wait to start the testing process if you don’t have to. Even if you ordinarily have standing to seek a DNA test, your state might have a statute of limitations as to when you can require an alleged parent to take a test.

Tampering with a DNA test can result in fines and jail time.

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Genetic Engineering 101

Genetic-Engineering-101Genetic engineering is a form of genetic modification in which selected genes are taken from one organism and implanted into another to have a desired effect. Genetic engineering enables researchers to improve all aspects of life by impacting areas such as medicine and pharmaceuticals and agriculture.

Genetic engineering or transformation is a popular topic because of its relevance to hot-button topics like cloning and Genetically Modified Organisms (GMOs) in food. Though many are quick to offer opinions on genetic engineering, few understand what it actually entails. Rare is the person who can speak knowledgeably on the practice of genetically engineering organisms, or its potential benefits.

Similarities and Differences – Traditional Breeding and Genetic Engineering

Genetic engineering is conceptually the same as natural breeding, in which genes are transferred from one organism to another. Both methods function to improve an organism’s traits to help the organism survive both natural and man-made environmental hazards.

In traditional breeding:

  • There is an equal (50-50) contribution of genes from the contributing organisms.
  • Desirable and undesirable traits have an equal likelihood of transferring, so genetic improvement is randomized.

In genetic engineering:

  • Genes are selected based on desirability and transmitted from one organism into another.
  • Genes can be selected from other species depending on desired improvements
  • Genetic improvements occur quickly when the process is successful.

While genetic engineering facilitates more selective trait modification, it does not eliminate the need for traditional breeding. This is because traditional breeding is necessary to improve the characteristics of the genetically engineered organism. Secondly, genetic engineering can be a time-consuming process, taking hundreds of attempts to create only a few successes.

Advantages Made Possible by Genetic Engineering

Genetic engineering has the ability to positively impact all aspects of life.

For example, take an off-shoot of the 2014 Ebola virus outbreak in which tobacco plants were infected with a virus that contained a specific gene of DNA. The infected cells began to produce an Ebola-fighting protein that was contained in the tobacco plant’s leaves, which could then be harvested. This innovative approach is called “pharming” and, if successful, could have a transformative impact on this otherwise incurable, highly fatal virus.

Other potential advantages resulting from genetic engineering include:

  • Human Cloning: Thanks to the completion of the human genome project and successful mammal cloning (the results of which are called xenographs), researchers have been able to enhance their understanding of the part DNA plays in all aspects of life.
  • Medicine: Crippling genetic diseases like heart disease, cystic fibrosis, ALS, and others are the results of gene defects. The only hope for cures is genetic modification of a defective gene, or implantation of a genetically modified gene. Researchers have already found gene therapy proves effective in treating heart disease; they have also discovered that genetic engineering enables the re-growth or repair of damaged or malfunctioning muscle cells.
  • Pharmaceuticals: Researchers have been able to better understand the formation of disorders and provide more effective treatment via innovative medicines created by genetically modifying plant DNA.
  • Prenatal Treatment:  Expectant mothers can currently test their fetuses for certain genetic defects. This is used to help families and doctors prepare if a baby will have special needs, but the future of genetic engineering holds promise that could enable expectant parents to choose to treat a genetic defect via gene therapy before the child is even born. Other research poses the possibility that partners could select the genetic traits of their future child.
  • Agriculture: Genetically engineered crops are more resistant to pestilence, drought, salinity, and viruses than non-modified plant species. The resulting plants are not only able to withstand the world’s increasing supply and demand for produce, but they are also able to address famine in countries where millions would either suffer or die otherwise. Realistically, without genetic modification, many plant species would not be able to withstand weed-killing herbicides.

Despite all of the benefits posed by genetic engineering, valid concerns remain on the part of the general public and some within the scientific community. A closely monitored ethical code relative to genetic research will continue to improve all aspects of life.




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How DNA Damage Impacts Your Body’s Ability to Heal

DNA damage can obstruct healing patterns The human body’s structure, function, and systemic regulation are controlled by our DNA.

Chemicals that make up DNA create codes for proteins that regulate and shape every facet of the body and its organs. This chemical makeup is vulnerable to various natural and man-made environmental compounds, collectively known as mutagens. The results include disease, accelerated aging, and impacts on the body’s ability to heal. Restoration of DNA sequences is about 99% efficient but, over time, the number of damaged strands adds up.

The Intricacy of DNA

Proteins are created out of information contained in a DNA sequence, called a gene. Genes can have up to 1 million base pairs of chemicals known as cytosine, guanine, thymine, and adenine. In sequence, these pairs code for proteins – up to 23,000 genes regulate our ability to grow, develop, and heal. Only a small amount of DNA makes up genes; most of it regulates the timing, quantity, and the conditions in which proteins are made.

DNA strands are replicated and copied many times. This process carries the risk of mistakes, which occur once out of every 100 million copies. Most of the time, the mistakes are fixed. But in other instances, they result in irreparable mutations.

There are several types of damage:

  • Errors in DNA code, which most often get repaired without incident.
  • Sections of a DNA strand get deleted from a sequence.
  • Extra genetic code is inserted in the strand.
  • DNA strands break, which can lead to more mistakes during repair.
  • Telomeres, at the ends of the chromosome, protect the DNA, but become shorter with each cell division. If they’re too short, cells stop replicating, die, or divide abnormally.

DNA Damage Triggers

Mutagens can replace the essential building block chemicals in DNA, make a normal nucleotide appear to be another, and cause serious damage. Some mutagens are carcinogens (those which directly cause damage leading to cancer). Cancer-causing chemicals can lead to disease or interact with other substances.

Cigarette Smoke

Cigarette smoke contains thousands of harmful substances. This includes even second-hand smoke, and what’s now known as third-hand smoke that stays on walls and in furniture. Researchers have identified over 70 different chemicals in the smoke which can cause cancer, as well as other poisonous substances. These include chemicals such as arsenic, cadmium, and acrolein which can prevent cells from repairing DNA. Nitrosamines and PAHs, or polycyclic aromatic hydrocarbons, can also damage DNA.

The University of California’s Tobacco-Related Disease Research Program completed a study on third-hand smoke earlier this year. This study identified over 4,000 compounds able to linger on furniture, on walls, or in the air inside a room. One cancer-causing compound, NNA, can link with DNA as seen in the laboratory. It can also break genetic material apart. Another nicotine byproduct called NNK does this as well and is known to trigger uncontrolled cell division. The program has published additional  information on environmental exposure on its website.

Ultraviolet Radiation

The base pairs in DNA are prone to damage from UV radiation. Ultraviolet light can make two thymines stick together, which can be fixed naturally. Otherwise the cell dies or potentially becomes malignant. This is a factor in how prolonged, unprotected sun exposure can lead to skin cancer. Other forms of radiation can break DNA, delete it, or stick it to other genetic strands. Sometimes it alters bases such that a guanine is structured more like an adenine. Unnatural pairings can result, having profound implications for people or their offspring.

Free Radicals

Free radicals are particles that cause oxidative damage. These occur naturally as byproducts of cellular metabolism. Damage from radiation exposure is in part caused by a form of free radicals. Hydroxyl radicals are common damage inducers and can break up DNA strands and initiate dangerous chemical changes.

Nutrient Deficiencies

Physical damage to DNA can result if there is a lack of vitamins such as B12, E, B6, and C in the body. Zinc, iron, and folate deficiencies can also cause damage and increase the risk of cancer. A lack of these substances, according to research at the University of California, can create as much damage as exposure to radiation.

Natural DNA Damage

Damage and errors in DNA repair tend to increase with age, sometimes proliferating across the genome. Aside from regular mutations and fixes, various pathways exist in how natural processes can restore original sequences. Non-homologous DNA end joining is one, but can cause permanent changes to the sequence called micro-deletions. Researchers have speculated a connection between higher numbers of micro-deletions and aging.

DNA Damage Is Inevitable

DNA includes the code for how our bodies develop, function, and heal. Damage multiplies with age or through exposure to chemicals, free radicals, or radiation. Nutritional deficiencies can do just as much harm. The body and its genome have a large capacity to repair damage. Too much damage and the code for repair or normal function may no longer exist, leading to many biological dysfunctions and diseases.



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What is Mitochondrial DNA (mtDNA) and How is It Used?

Uses of mtDNA Most of us are familiar with the idea that we inherit our genes from both our mother and our father. It’s true that inside every one of our body’s cells there is a roughly equal mix of DNA from our parents. The vast majority of this parental DNA resides in the nucleus of the cell.

There is a compartment inside every cell designed to enclose and maintain the DNA and to regulate access to all the information within. But there is another area that also contains DNA. This compartment, called the mitochondria, is specialized for producing the energy that each cell needs to function, and it is the reason that we are able to move our muscles or even think thoughts.

What’s mtDNA?

The DNA inside of mitochondria (called mtDNA) is unlike the DNA inside the nucleus in that all of it comes from our mothers.  In other words, unlike the DNA inside the nucleus, it is not a mixture of our parent’s DNA, and each person’s mtDNA is nearly identical to his or her mother’s mtDNA. mtDNA contains a small number of genes (37 in all). That’s not very many compared to the number in the nucleus (about 20,000).

However, whereas there are only two copies of each gene in the nucleus, there can be 10 or more copies of each gene in the mitochondrion. What’s more, there are hundreds to thousands of these mitochondria in every cell, meaning there are many thousands of copies of each mitochondrial gene in each cell.

The special characteristics of mtDNA make it useful for certain types of DNA testing.  In crime scene investigations, the amount of this DNA is a critical factor in determining what kind of information forensic scientists can retrieve and whether they can identify the individuals at the scene.  When there is not enough of the nuclear DNA to analyze, there is often enough mtDNA because there are so many copies of it in every cell and because it is often more stable than nuclear DNA. Analysis of mtDNA cannot always identify a specific individual at a crime scene, but it can identify a specific family.

DNA for Ancestry
A common public use for mtDNA in DNA testing is in determining ancestry.  Because mtDNA does not change as rapidly as nuclear DNA, and because it is not mixed with the father’s (paternal) DNA, it leaves a clearer record of distant ancestry – although only through the mothers’ (maternal ancestry).  Analysis of mtDNA is what allowed scientists to trace the maternal ancestry of all human beings to East Africa and to a time roughly between 100,000 and 200,000 years ago.

mtDNA testing can provide some kinds of information about ancestry not always apparent from regular DNA testing.  For us non-scientists because mtDNA is shared among all people with the same maternal ancestry, it can provide some of the clearest proof of relationships among people with the same mother, grandmother, great grandmother, and so on.

Muscle Weakness
mtDNA testing is also important for diagnosing certain diseases.  Mutations in the genes found in mtDNA have been shown to cause many different types of disease, often neuromuscular diseases or other diseases that cause muscle weakness.  The three-time winner of the Tour de France, Greg Lemond, gave up competitive cycling when he developed muscle weakness and fatigue.  He was diagnosed with a mitochondrial disease called “mitochondrial myopathy” in 1994, and his New York Times story was perhaps the first to put mitochondrial diseases in the public eye.

Scientists have also determined that mutations in mtDNA are associated with symptoms and diseases of aging, leading to the theory that mitochondrial DNA changes are important for determining how rapidly people age. In the future, mtDNA testing could become an important part of determining a person’s overall health.  Even subtle changes in mtDNA may be important for determining your overall feeling of energy and well-being.




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Fetal DNA Testing – New Parameters

Fetal DNA Testing has come a long wayNon-invasive prenatal testing (NIPT) of DNA is a new and expanding option for pregnant women.

Research has shown it to be accurate for detecting trisomy, in women who are considered low or high risk. Trisomy exists when there are three copies of a chromosome instead of the normal two. Clinical studies have pointed to the accuracy and safety of individual non-invasive tests. These have been found to detect suspect trisomies such as Down Syndrome nearly 100% of the time.

New guidelines are emerging regarding NIPT, despite the cautious optimism of medical societies. A Royal College of Obstetricians & Gynecologists study favors it. The organization, however, issued a statement regarding the method’s sensitivity and possible reasons test errors may occur in the processing, not the science. Factors can include gestational age, maternal obesity, placental abnormalities, and twins.

A paper by the Society of Maternal Fetal Medicine identifies NIPT as promising, yet current practices and recommendations should remain in place. The organization emphasizes a need for evaluating the test method for additional types of trisomies, specifically with cell-free fetal DNA.

Nonetheless, noninvasive testing seems to be catching on. Expanded use and additional studies promise to make this method more widespread. Findings on its accuracy and benefits are catching the attention of the general population and the medical community.
Accuracy Rates
Non-invasive prenatal testing is a viable method for detecting several leading chromosomal abnormalities. For example, it exhibits a 99%+ detection rate for trisomy 21, or Down Syndrome, according to the NCHPEG and a BlueCross BlueShield technology assessment mentioned in an Oxford Health Plans, LLC clinical report.

Additional findings include:

• Trisomy 18 (Edward’s Syndrome): Similar to that of trisomy 21, the detection rate has been found to be 98-99%.
• Trisomy 13 (Patau Syndrome): The NHCPEG cites a 79-92% detection rate. If a pregnancy involves an affected fetus, the condition might not be detected, so traditional testing is needed to confirm a diagnosis if Patau is suspected.

False positive rates of about 1% have also been found. Even if a positive result is indicated, additional testing is often recommended following NIPT. False negative results happen, as well, which is why many laboratories provide a risk score with reports. In some cases, insufficient levels of fetal DNA in a sample can skew the test results. Aside from these possibilities, non-invasive testing is highly effective in detecting the most common trisomies.
How It Works
Non-invasive fetal DNA testing is performed using the mother’s blood. There are a couple of methods.

Massive parallel shotgun sequencing is used to measure the proportion of targeted chromosomes and compare the number with standard guidelines.

Another way is to compare specific parts of the chromosome with what is expected. Laboratories can report the results as positive or negative, consistent with specific conditions, or as a percentage of risk. For those with insurance, coverage can vary depending on the policy because the test is new.

NIPT is a low-risk test method that can be performed relatively early in pregnancy. Results can be obtained in a week, though sometimes longer. Methods such as amniocentesis and chorionic villus sampling (CVS), on the other hand, can take up to two weeks. An ultrasound is not needed for interpreting results or guiding physicians during the procedure.

• Risk: The new testing can detect and analyze fetal cell-free DNA fragments without penetrating the womb. These are found in the mother’s blood from 8 weeks on. NIPT requires just a blood test, without the risks of traditional, more invasive procedures such as CVS or amniocentesis. In rare cases, these more invasive methods can harm the baby or trigger miscarriage.

• Recommendations: For pregnant women 35 or older, NIPT is a safer procedure. Testing is also suggested if ultrasound results point to an increased risk, or if someone previously was pregnant and there was a chromosomal condition involved. Positive test results in the early trimesters should be followed up with NIPT later on. Use guidelines also suggest false positives be confirmed using CVS or amniocentesis.

Major medical societies anticipate NIPT will expand in the long term. For some chromosomal abnormalities, it is almost as accurate as other diagnostic methods. Its accuracy has primarily been proven in higher risk cases. Usefulness in low risk pregnancies is expected to be gauged soon according to an NHCPEG factsheet. Future studies may also weigh in on NIPT for pregnancies involving more than two fetuses or egg donations. More women are electing to have the non-invasive test. More data will therefore provide updated results on performance and accuracy concerning a range of factors and conditions.




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What is Forensic DNA Testing?

questions answered about DNA testing proceduresForensic DNA testing is the use of DNA testing in solving crimes and it has become very useful for law enforcement and achieving true justice. DNA testing has proven useful in both convicting and exonerating criminal suspects in both current and cold cases. Additionally, progress in forensic DNA testing enable results to be provided more quickly and accurately.

Popular television programs such as the CSI series, Cold Case, and Forensic Files have increased public knowledge about the usefulness of forensic DNA in solving crimes. Because each person’s genetic make-up is unique, the results of forensic DNA testing are highly reliable and are often used by the legal system to convict or exonerate suspects in crime investigations.

Collecting DNA Evidence

By virtue of the meaning of the word “forensic”, this type of DNA testing pertains to using scientific knowledge to solve crimes. DNA evidence was first used in England in 1985 where a 17 year-old boy was suspected of raping two young women; DNA exonerated the boy, and the real perpetrator was eventually caught.

In the United States, the first case to use DNA evidence was a case in New York in 1987. The evidence was explained by Dr. Michael Baird, now the Laboratory Director at DNA Diagnostics Center. Since then, using DNA evidence has become an increasingly reliable method to help solve crimes.

Part of the reason DNA evidence is so useful is because DNA is inside every part of the body including:

  • Hair strands or follicles
  • Blood and bodily fluids including sweat, saliva, mucus, etc.
  • Fingernails, skin cells and bones

Such samples are often found on:

  • Clothing, including socks, sweatshirts, underwear and hats.
  • Bed sheets or bath towels
  • Discarded tissues, condoms, bandages, cigarette butts, etc.
  • Drinking glasses and silverware
  • Abandoned weapons, tape, or gloves, and more.

Sweat, skin cells, blood, bodily fluid, and hair samples are often found at crime scenes. Samples are collected by swabbing or by preserving any item on which DNA could reside. In the past, law enforcement departments have been criticized for poorly handling evidence in investigations, which can have disastrous results. So, regardless of how robust forensic DNA testing becomes, the utmost care should be taken at all times to eliminate the possibility of human error.

Conducting a DNA Analysis

Once DNA evidence is collected, it must be compared to another sample to achieve a match. The most common  four potential results of a forensic DNA test are:

  • Inclusions, which occur when a sample is consistent with the unknown sample collected from a crime scene.
  • Exclusions mean that the sample provided by the known contributor does not match the unknown sample from the crime scene.
  • Inconclusive Results could occur for when the unknown sample yields partial or no results or there are no known suspects available to compare to the crime scene DNA samples collected.
  • No DNA obtained meaning that no DNA was extractable from the provided sample.

To both determine and refine matches or inconclusive results, the DNA samples collected undergo an analysis using several DNA testing systems, the most common of which are:

  • Short Tandem Repeat (STR) analysis tests loci on nuclear DNA; there are 13 STR loci in the CODIS index (Combined DNA Index System), which is the Federal Bureau of Investigation’s support program for criminal justice DNA databases. CODIS’ mission is to aid investigations, and as of June 2014, CODIS produced over 250,809 hits assisting in over 239,317 investigations.
  • Y-Chromosome Short Tandem Repeats (Y-STR) targets the male or Y Chromosome of a provided sample, increasing the validity of results.
  • Mitochondrial DNA (mtDNA) Sequencing tests samples that are in the mitochondrion and that otherwise lack the ability to be tested by other means. This form of testing is especially useful in solving cold cases or where samples might be degraded.

When DNA results are confirmed, the likelihood of inaccuracies provided no human error occurred is practically infinitesimal.

The Uses of Forensic DNA Testing

Conclusive DNA test results have innumerable capabilities within the legal system. Thanks to TV crime dramas, the most commonly recognized use of forensic DNA testing is courtroom convictions. However, DNA has also been widely used to exonerate alleged criminals as well. To date, more than 300 people have been freed thanks to DNA analysis; around 20 of those people were on death row.

  • Cold Cases have been able to be solved thanks to DNA evidence as well as local and national DNA databases like CODIS. Advents in forensic testing like new Rapid DNA technology expedites DNA testing from weeks or months to mere hours. Rapid technologies will enable labs to quickly process new cases providing time to focus on backlogs.
  • Forensic Paternity testing is useful in missing persons or victim identification when a suspected family member is able to provide a sample. It is also helpful in proving rape or incest cases when conception results.

Over the past 29 years, DNA testing has revolutionized forensic investigations. Forensic DNA testing provides stronger results whether they are inclusions, exclusions, or inconclusive lending to a greater confidence in the justice system. Additionally, forensic DNA testing has played a significant role in righting wrongs where the justice system has failed, largely due to less than accurate evidence. The future of this science holds promise that it will not only be more accessible but also more reliable.


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