By Laura Shin
Posting in Healthcare
The non-invasive procedure improves upon existing pre-birth paternity tests that carry a small risk of inducing a miscarriage.
Nature didn't make it easy to figure out who the father of a child is. But science now can.
In instances when a prospective mother is uncertain about the paternity of her child, a new, reliable test can determine it even in the first few months of fetal development.
Furthermore, the test can pinpoint paternity using a non-invasive procedure; existing reliable pre-natal paternity tests such as amniocentesis are invasive and carry a small risk of miscarriage.
How the tests works
The tests require blood samples from the mother and from one of the prospective fathers (if there are two), and doctors may not even have to get involved. The test then measures DNA fragments from the fetus that will be present in the mother's blood.
(This method is also what enables a fetus's entire genome to be decoded from a mother's blood sample and a father's saliva.)
Although noninvasive prenatal paternity tests have been offered on the Internet for about a decade, users of those have complained about inaccurate or fraudulent results.
An experiment with a small sample size showed the new test to be reliable: The New England Journal of Medicine published results showing that the test accurately determined paternity in 30 cases.
That study was of a paternity test by Ravgen, a small Maryland company that has been offering its test for $950 to $1,650, depending on the circumstances, according to The New York Times.
Another test offered by a Silicon Valley company called Natera costs $1,775, and is marketed by the DNA Diagnostics Center, which specializes in conventional paternity tests. The results of the Natera test's accuracy have not been published in any peer-reviewed journals.
Additionally, neither test has been certified by the American Association of Blood Banks for the accuracy necessary for child custody cases; the AABB is currently considering whether to certify prenatal tests.
The impact of prenatal paternity tests
The pregnancy "discrepancy rate" is -- the percentage of pregnancies in which the presumed father is not actually the biological father -- It is not known exactly. Studies have come up with figures ranging from 0.8% to 30%, with the median being 3.7%.
Whatever the exact number, there are a few consequences these reliable, noninvasive prenatal tests could have: First, they could vastly expand testing, Sara Katsanis of Duke University’s Institute for Genome Sciences and Policy told The Times.
Second, early testing could increase paternal support for pregnant women, since as one woman who was uncertain of her child's paternity told The Times, “Neither [of the possible fathers] really wanted to be involved and then find out the baby wasn’t theirs later.” After she got the test, the father attended the delivery and supported the child.
Another possibility is that they increase the number of abortions, as mothers find out that their unborn fetuses are not the children of their desired fathers. However, Ravgen's chief executive, Dr. Ravinder Dallan, also surmises they will prevent abortions by mothers who have been raped, if they find out the father is not the rapist.
Likely, the impact will be a combination of all the above.
What do you think? Do you think that the tests will benefit mothers and babies, and that the good of those tests will outweigh the bad of any increase in abortions? Or do you think that the tests will only increase abortions, not support for the mothers and children?
Related on SmartPlanet:
- Coming soon: $1,000 to map your genes
- Chinese medical school teaches genetics using Harry Potter
- Top 10 most interesting genetic findings of 2011
photo: Drawing by Leonardo Da Vinci (Wikimedia)
Jun 25, 2012
We, at the Denver DNA Center, agree that Non Invasive is the way to go when it comes to prenatal testing but until it is accredited by the AABB the invasive prenatal testing is what will hold up in a court of law. During our free consultation, we don't discourage expectant mothers from getting the invasive prenatal test but we also warn against the potential harms the the baby if this is chosen. We also go to great length to understand if the expectant mother is fully aware of the risks involved, and whether or not she discussed in detail with her OB-GYN. For more information on our invasive prenatal testing (until we can offer AABB accredited non invasive prenatal testing), contact us at www.denverdnacenter.com.
My name is Jonathan Miller and I work with Paternity Testing Corporation based in Columbia, Missouri. We have seen many companies market this technology with varied results and have been hesitant to provide the service until we were able to find a reliable method for separating the mother's DNA from the unborn child's. We have been in the paternity testing business since the mid-90s and have a strong reputation to keep when it comes to family relationship testing. We have only recently began offering a highly reliable prenatal paternity test. Please feel free to contact us if you would like to discuss it in further detail at no charge. http://www.ptclabs.com Best regards, Jonathan
Non-invadive prenatal testing is the desire of both the mnedical community and the public.Testing for paternity and genetic conditions without doing an invasive sampling method such as CVS or amniocentesis is a dream at this stage. I counselled a woman who was determined to do non-invasive prenatal testing as she did not wish to chance loosing the pregnancy. She had the DNA work done at a respected clinic in the USA where via peripheral blood testing the alleged father had paternity confirmed. Once the baby was born we tested( in our Australian accredited laboratory) the alleged father and he was not the father of the newborn baby and paternity was confirmed with another man. I find it distressing that DNA companies market this technology for which the results have huge implications and get the result wrong. The mother is so relieved that she did not terminate the pregnancy .Non-invasive prenatal testing is not accepted in Australia by medical specialists and consumers should be aware of its limitations and discuss with either their clinician or their genetic counsellor.
[Re: Dolly5664] Hi Everyone, I want to discuss some of the confusion on this message board around non-invasive prenatal paternity testing. Currently there is a method available to test paternity from a simple maternal blood draw as early as 9 weeks gestation with >99% accuracy. Additionally, cheek swab samples from the alleged father(s) are required and results are returned in 5 business days. More information can be found: http://www.natera.com/non-invasive-prenatal-paternity-test.html Natera's method for accurate, validated testing was published last year at the International Society of Human Identification Meeting in 2011: http://www.natera.com/assets/files/natera-conference-abstracts/7-Paternity-ISHI-2011-Abstract-Submission.pdf This is the most well-respected meeting related to the world of paternity testing and brought doctors and scientists from all over the world to discuss advances in non-invasive prenatal paternity testing. There are a lot of misconceptions out there around this type of testing, so please ensure to do your research and make an educated decision based on published data that you can trust.
You are clearly writing on behalf of a laboratory. Why donât you identify yourself? Also why donât you name the is ârespected clinic in the USAâ? Are you afraid of being sued for posting unverified comments? Why are you putting fear into people that performed this test? Unless you are willing to identify the parties then your comments should be removed by the moderator.
Hi, Just out of curiosity which company did your friend use? I had a test done back in January by Natera Inc., I'm just curious which clinic you are referring to. Your posting made me nervous that my test results are not accurate.