New Forms of DNA Fingerprinting
With new forms of DNA fingerprinting, tests for genetic disorders have become far more rapid and efficient. In fact, it may soon be less challenging as well as safer to find out if a pregnant woman's baby has a genetic condition.
A Drop of BloodResearchers studying a new method found that by simply taking a single drop of a mother's blood, they could discover if the foetus had a genetic condition such as cystic fibrosis. This new DNA testing would avoid using amniocentesis, where a physician has to take amniotic fluid found around the foetus – a known risk for miscarriage.
In this way, the new DNA test is far less invasive than previous methods of testing for genetic disease. Yet, how does the test work exactly?
Using Foetal DNA TestingA pregnant woman's blood does not just contain her own DNA, but also it contains the DNA of her unborn child. By taking a blood sample from a pregnant woman, doctors can screen for a variety of disease genes while safeguarding the foetus and mother's health.
Some conditions such as cystic fibrosis occur from recessive gene inheritance. The baby would inherit a copy from the mother and a copy from the father. Screening for this disease has become increasingly important, although current testing methods are far from perfect.
However, just because the recessive gene for the disease is detected in the mother's blood, does not mean that the foetus will automatically develop the condition. As such, if the gene is detected, it may only be that the mother has a copy of the gene or the foetus has inherited one copy rather than two copies of the gene.
Fortunately, the new technique of screening via the mother's blood can address this issue. The technique is called digital Polymerase Chain Reaction (dPCR). When researchers used this technique, they were able to actually count the number of copies that were present – after taking a blood sample from a pregnant woman.
Developing Improved TestingThe study is still one that requires additional research before the technique can be widely used as a screening tool. However, it does show promise because it allowed researchers to more accurately determine if the foetus would develop the genetic condition. Scientists are hoping to conduct bigger experimental trials, which will lend more credibility to the technique and hopefully provide more information about how it works and any challenges that need to be investigated.
Abortions or MiscarriagesWhile this less invasive test means that a woman's risk of a miscarriage from the traditional methods of detecting disease is lowered, some people are worried that this new screening tool will lead to more women having abortions. Some say that disorders such as Down's syndrome have better outcomes today and that a woman should not abort a foetus who has the disorder.
Ultimately though, it does come down to personal choice. This new technique is one that informs the parents of whether the foetus has a genetic disease and it allows them to look at their options and make an informed decision about how to proceed.