Prediction of fetal sex by amplification of fetal DNA present in cow plasma.

The aim of the present study was to predict fetal sex at different time points of gestation in cattle by detecting the fetal SRY gene in cow plasma. Plasma DNA was extracted from the blood samples of 110 pregnant cows during the gestational period of 30 to 242 days. Nested PCR was employed to detect the fetal SRY, which the male fetus carries exclusively, in cow plasma. The cows positive for SRY were predicted to carry male fetuses. The results showed that the fetal DNA from cow plasma was successfully amplified and that fetuses could be sexed with an overall accuracy rate of 100% (43/43) for males and 91.0% (61/67) for females and with accuracy rates of 100% (3/3) for males and 85.7% (12/14) for females at 30 EN 59 days of gestation and 100% (40/40) for males and 92.5% (49/53) for females at more than 2 months of gestation, respectively. This suggests that the molecular method developed here could be used in sex prediction for fetuses.