Methods for non-invasive prenatal screening and testing using cell free fetal DNA (cfDNA) found circulating in maternal blood are being developed. Testing for certain (sex-linked and skeletal) conditions is currently available in the UK with tests for other conditions including Down syndrome being developed/trialed. [More info is available from the RAPID (Reliable Accurate Prenatal non-Invasive Diagnosis) project.]
An international, multi-centre study (4,002 pregnant women from the US, Netherlands and Sweden) has recently reported that a genetic test to screen for trisomy 21 or 18 from a maternal blood sample is almost 100% accurate. See the news report for more information and link to the original article.
It is very likely that this type of early screening and testing will become widely available in the UK in the not too distant future. Removing the risk of miscarriage associated with invasive testing methods like amniocentesis and chorionic villus sampling is a huge bonus, but it will be important to ensure that midwives and other health professionals offering these tests are appropriately trained to ensure that women fully understand what they are consenting for early on in the pregnancy.
I’m looking forward to the European Society of Human Genetics meeting this week – there are a number of presentations on NIPD – so it will be good to hear the least views on the topic.