Lack of association between human papillomavirus types 6 and 11 genetic variants and cervical abnormalities: The ludwig-mcgill cohort study

Abstract

Background: Human papillomavirus (HPV) types 6 and 11 are mainly associated with the development of genital warts and recurrent respiratory papillomatosis. We examined intratypic genetic variability of both viral types with the development of cervical cytologic abnormalities in Brazilian women. Methods: We used PCR sequencing to characterize variants of HPVs 6 and/or 11 in cervical swabs from women in the Ludwig-McGill Cohort Study. We used a binomial generalized estimating equations (GEE) model with logit link to estimate odds ratios (OR) and 95% confidence intervals (CI) for the associations between HPV 6 and 11 variants and cytologic abnormalities. Results: B1 and B3 HPV6 and A2 HPV11 variants were the most common isolates identified. Compared with HPV6-negative women, the ORs among women harboring HPV6 B1 or B3 variants were 6.3 (95% CI, 2.3-17.0) and 2.3 (95% CI, 0.6-9.7) for atypical cells of undetermined significance (ASCUS)/low squamous intraepithelial lesions (LSIL), respectively, and 1.7 (95% CI, 0.6-5.1) and 1.2 (95% CI, 0.3-4.7) for ASCUS/LSIL/high squamous intraepithelial lesions (HSIL). Respective ORs were 5.0 (95% CI, 1.7-14.6) and 2.8 (95% CI, 1.0-8.1) upon comparing women with HPV11 A2 variants to HPV11-negative women. All associations disappeared when adjusting for coinfections with high-risk HPV types. Conclusions: Our data do not support an association between low-risk HPVs 6 and 11 genetic variability and cervical abnormalities. Impact: Risk of cervical cytologic abnormalities is not affected by intratypic polymorphism in HPVs 6 and 11.