New variants of E6 and E7 oncogenes of human papillomavirus type 31 identified in Northeastern Brazil.

Objective: We sought to characterize E6 and E7 oncogenes genetic variability of HPV-31 isolated from cervical scraping samples of Northeastern Brazilian women.

Methods: E6 and E7 were amplified with specific primers, cloned and sequenced. The sequences obtained were aligned with the GenBank reference sequences with the aim of evaluating the possible genetic variants.

Results: We identified several genetic variants in E6 and E7 sequences from HPV-31 positive women. Three nucleotide changes in E6 were described for the first time in this study. Some nucleotide changes were non-synonymous substitutions.

Conclusion: The knowledge of region/country HPV specific genetic variations is relevant to understand the epidemiology and the development of effective vaccines.