Non-invasive prenatal testing using massively parallel sequencing of maternal plasma DNA: from molecular karyotyping to fetal whole-genome sequencing

The discovery of cell-free fetal DNA in maternal plasma in 1997 has stimulated a rapid development of non-invasive prenatal testing. The recent advent of massively parallel sequencing has allowed the analysis of circulating cell-free fetal DNA to be performed with unprecedented sensitivity and precision. Fetal trisomies 21, 18 and 13 are now robustly detectable in maternal plasma and such analyses have been available clinically since 2011. Fetal genome-wide molecular karyotyping and whole-genome sequencing have now been demonstrated in a number of proof-of-concept studies. Genome-wide and targeted sequencing of maternal plasma has been shown to allow the non-invasive prenatal testing of β-thalassaemia and can potentially be generalized to other monogenic diseases. It is thus expected that plasma DNA-based non-invasive prenatal testing will play an increasingly important role in future obstetric care. It is thus timely and important that the ethical, social and legal issues of non-invasive prenatal testing be discussed actively by all parties involved in prenatal care.The discovery of cell-free fetal DNA in maternal plasma in 1997 has stimulated a rapid development of non-invasive prenatal testing. The recent advent of high-throughput sequencing technologies has allowed the analysis of circulating cell-free fetal DNA to be performed with unprecedented sensitivity and precision. A number of fetal chromosomal disorders are now robustly detectable in maternal plasma and such analyses have been available clinically since 2011. Moving beyond selected fetal chromosomal disorders, fetal single-gene disorders and even fetal whole-genome analysis have now been demonstrated in a number of proof-of-concept studies. It is thus expected that DNA-based non-invasive prenatal testing will play an increasingly important role in future obstetrics care. It is thus timely and important that the ethical, social and legal issues of non-invasive prenatal testing be actively discussed by all parties involved in prenatal care.