Detection of Y chromosome-specific DNA in the plasma and urine of pregnantwomen using nested polymerase chain reaction

The present study was undertaken to evaluate a nested polymerase chain reac tion (PCR) for detection of Y chromosome-specific fetal DNA in maternal pla sma and urine of pregnant women during different gestational stages. DNA is olated from plasma and urine samples of 80 pregnant women (between 7 and 40 weeks' gestation) underwent amplification for Y chromosome-specific 198 bp DNA by nested PCR. The postpartum analysis of fetal gender showed that 55 women carried male and 25 female fetuses. Among the 55 women bearing male f etuses, Y chromosome-specific signals were detected in 53 (96%) plasma and 21 (38%) urine samples. Moreover, out of 25 women bearing female fetuses, 3 (12%) and 1 (4%) women had Y chromosome-specific signal in plasma and urin e, respectively. Analysis of results with respect to gestational age reveal ed that there was no significant difference in the detection of Y chromosom e-specific DNA between different trimesters in maternal plasma of women bea ring male fetuses. These results showed that fetus-specific DNA was detecte d with high sensitivity (96%) and specificity (88%) in the maternal plasma by nested PCR, and therefore the method could be useful as a non-invasive p rocedure for fetal sex determination and prenatal diagnosis. Copyright (C) 2001 John Wiley & Sons, Ltd.