Rapid quantification of semen hepatitis B virus DNA by real-time polymerase chain reaction.

AIM To examine the sensitivity and accuracy of real-time polymerase chain reaction (PCR) for the quantification of hepatitis B virus (HBV) DNA in semen. METHODS Hepatitis B viral DNA was isolated from HBV carriers' semen and sera using phenol extraction method and QIAamp DNA blood mini kit (Qiagen, Germany). HBV DNA was detected by conventional PCR and quantified by TaqMan technology-based real-time PCR (quantitative polymerase chain reaction (qPCR)). The detection threshold was 200 copies of HBV DNA for conventional PCR and 10 copies of HBV DNA for real time PCR per reaction. RESULTS Both methods of phenol extraction and QIAamp DNA blood mini kit were suitable for isolating HBV DNA from semen. The value of the detection thresholds was 500 copies of HBV DNA per mL in the semen. The viral loads were 7.5X10(7) and 1.67X10(7) copies of HBV DNA per mL in two HBV infected patients' sera, while 2.14X10(5) and 3.02X10(5) copies of HBV DNA per mL in the semen. CONCLUSION Real-time PCR is a more sensitive and accurate method to detect and quantify HBV DNA in the semen.