Realising the promise of non-invasive prenatal testingBMJ 2015; 350 doi: https://doi.org/10.1136/bmj.h1792 (Published 10 April 2015) Cite this as: BMJ 2015;350:h1792
- Lyn S Chitty, professor of genetics and fetal medicine1,
- Mark Kroese, consultant in public health medicine and programme director2
- 1UCL Institute of Child Health and Great Ormond Street NHS Foundation Trust, London WC1N 3BH, UK
- 2PHG Foundation, Cambridge CB1 8RN, UK
- Correspondence to: L S Chitty
The presence in maternal plasma of cell-free fetal DNA, which is pregnancy specific1 and represents the whole of the fetal genome,2 offers enormous promise for the development of a wide range of prenatal genetic tests. Such tests require only a maternal blood sample rather than an invasive procedure that carries a risk of miscarriage. Several applications have already been approved for clinical use in the NHS. These have largely been based on the detection or exclusion of genetic changes in the fetus but not present in the mother (because they have been inherited from the father or arisen de novo at conception). Analysis of fetal sex from cell-free DNA can be used to guide invasive testing when the fetus is at risk of sex linked disorders,3 and several other tests are available for definitive prenatal diagnosis of some monogenic disorders.4 In parts of Europe, and hopefully soon in the United Kingdom, fetal RHD genotyping is routinely offered to Rhesus negative mothers to inform anti-D administration.5 However, it is the development of non-invasive testing for aneuploidy that stands to have the greatest impact on maternity care.
The first proof of principle studies, using next generation sequencing to detect Down’s syndrome by analysis of cell-free …