摘要
On the basis of the characteristics of Y-chromosome sequence which consists of Y specific repeat DNA family(DYZI) of 800￣5 000 copies,a pair of primers Y3,Y4 is designed to amplify the specific DNA segment of 446 bp by the polymerase chain reaction(PCR),so as to detect the presence of Y chromosome in male fetal cell in maternal peripheral blood for the purpose of prenatal determination of fetal sex.The authors made use of PCR amplification of crude DNA from maternal peripheral blood in early, mid,and late pregnancies to determine the fetal sex.Comparison of the results with those of PCR of their corresponding chorionic villi and amniotic fluid,and with the sex of the aborted fetus or the new born showed coincident rates of 93%,100%,and 87. 5% in early, mid,and late pregnancies respectively.The procedure offers a new alternative way for non-invasive prenatal diagnosis,
