Advances on circulating fetal DNA in maternal plasma

The discovery of cell-free fetal DNA in maternal plasma in 1997 has opened up new possibilities for noninvasive diagnosis. By RT-PCR, circulating fetal DNA can be detected in the plasma of pregnant women, even in the first trimester of pregnancy, and thus can be used for noninvasive prenatal diagnosis of sex-linked disorders, the RhD status of fetuses, and single gene disorders such as beta-thalassaemia, congenital adrenal hyperplasia, and achondroplasia. In addition, quantitative aberrations of circulating fetal DNA may indicate various pregnancy-associated disorders, including preeclampsia, preterm labor and fetal trisomy 21.