Real-time PCR reactions were performed using Roche Lightcycler TaqMan master mix. Each reaction consisted of 1X Roche Lightcycler TaqMan master mix (Roche Diagnostics, Indianapolis, Indiana, USA), HPV-specific primer pairs and fluorescently-tagged probes for types 6, 11, 16, and 18 in a total reaction volume of 10 ml as previously described [15 (link)]. Real-time PCR reactions that target the E1 region of HPV were performed using Roche Lightcycler Sybr Green master mix (Roche Diagnostics), and sequencing of PCR products was performed as previously described [15 (link)].