Detection of fetal SRY gene from cell-free fetal DNA in maternal peripheral blood

Objective To detect fetal SRY(sex determining region of Y chromosome) gene from cell-free fetal DNA in maternal peripheral blood.Methods Peripheral blood samples were collected from 33 pregnant women with gestation 8-12 weeks,who underwent artificial abortion.Cell-free fetal DNA was extracted from maternal plasma.The SRY gene from fetal DNA were detected by PCR,Real-Time quantitative PCR and primer-extension preamplification(PEP)-PCR,respectively.The detection of SRY gene from fetal tissues was used as gold standards.Results The sensitivity of PCR,PEP-PCR and Real-Time PCR for detection of SRY gene in maternal plasma was 58.82%,88.24%and 88.24%,respectively.The specificity of three methods were all 100.0%.Conclusion Both the PEP-PCR and Real-Time PCR techniques can improve the sensitivity and accuracy of SRY gene detection in maternal blood.