Non-invasive prenatal diagnosis by fetal nucleic acid analysis in maternal plasma: the coming of age.

Prenatal diagnosis is an important part of obstetrics care. In the current prenatal programmes, definitive diagnosis of fetal genetic or chromosomal conditions is conducted through fetal sampling by amniocentesis or chorionic villus sampling. To obviate the risks of fetal miscarriage that are associated with the invasive sampling procedures, we have been developing non-invasive prenatal diagnostic tests based on cell-free fetal DNA analysis from maternal plasma. To date, fetal sex and rhesus D status determination by circulating fetal DNA analysis is performed clinically in many centres. Strategies for the non-invasive diagnosis of monogenic diseases have been developed. Accurate detection of fetal trisomy 21 by next-generation sequencing has been achieved. Many of the non-invasive prenatal tests could be introduced to the clinics as soon as cost-effective and high throughput protocols are developed.