Abstract
HPV16 is the most carcinogenic HPV type, but only a minority of HPV16 infections progress to cancer. Intratype genetic variants of HPV16 have been suggested to confer differential carcinogenicity. To investigate risk implications of HPV16 variants among Chinese women, a case-control study was conducted with 298 cervical cancer patients and 85 controls (all HPV16-positive). HPV16 isolates were predominantly of the A variant lineage, and variants of A4 (previously named Asian) sublineage were common. A4Asian variants were significantly associated with increased risk of cervical cancer compared to A1-3 (OR 1.72, 95 CI 1.04-2.85). Furthermore, a meta-analysis including 703 cases and 323 controls from East Asia confirmed the association (OR 2.82, 95 CI 1.44-5.52). In conclusion, A4 variants appear to predict higher risk of cervical cancer among HPV16-positive women, which may provide clues to the genetic basis of differences in the carcinogenicity of HPV16 variants.