Thanks to advancements in DNA testing science, there is now a safe, non-invasive way to take a DNA sample from an un-born baby. Prenatal DNA testing has a number of uses, from looking for signs of genetic diseases to determining the father of an unborn child.
Until recently, testing a child during pregnancy was difficult, risky and invasive. The new technique in contrast involves a quick & simple blood sample from the pregnant mother.
The old way
The old ‘invasive’ method of collecting a DNA sample involved passing a large needle into the womb and collecting a sample of amniotic fluid or a small piece of the placenta. The procedure was not only unpleasant for the mother, it also carried a small risk of miscarriage and other complications. As a result, doctors would often refuse to do this test unless there was an urgent medical need that justified the risks.
Simply wanting to know the paternity of the baby would not usually be adequate justification to do the test.
The new non-invasive method
This changed with the discovery of cell-free fetal DNA. Put simply, scientists have found that very small amounts of the baby’s DNA are present in the mother’s bloodstream during pregnancy. Scientists can take a blood sample from the mother and isolate the baby’s DNA using a technique called Massively Parallel Sequencing (MPS).
All that’s needed in order to do this test is a blood sample taken from the arm – the same kind of blood sample routinely taken by doctors all the time. You’ve probably had a blood sample taken yourself.
This method is quick, relatively painless and risk-free.
Prenatal paternity testing
The new non-invasive method has opened up the doors for prenatal paternity testing. If there are doubts over who is the father of an unborn child, the baby can be tested for paternity before birth. The mother provides a blood sample, the potential father provides a DNA sample via a mouth swab, and a testing company can compare the two DNA samples back in the laboratory.
A child inherits exactly 50% of their DNA from each parent so paternity tests are always accurate, just as long as a viable DNA sample can be extracted.
How to order a test
If you or someone you know is thinking about ordering a DNA test, be sure to use an accredited & approved lab. A standard paternity test can be purchased for around £99/$119. Prenatal paternity testing starts at around £875/$975. If you need a test for official reasons, you will need to pay a little extra for a legal test.
You can find advice, support and further information about paternity testing at Family Lives.