[The analysis of human papillomavirus type 16 E6/E7 genetic variability in Yunnan Province, China]

To investigate E6 and E7 gene variations of human papillomavirus type 16 in Yunnan Province, DNA was extracted from 2000 gynecological outpatient samples. For Human papillomavirus (HPV) genotyping, the genomic DNA was first amplified by the consensus MY09/MY11 primer pair followed by nested PCR with GP5+/GP6+ primers, then the PCR products were subjected to direct DNA sequencing. A total of 20 HPV-16 viral DNAs were identified. E6 and E7 genes of HPV-16 viral DNA were then amplified using E6 and E7 specific primers, the PCR products were purified and sequenced. The results showed that mutations were found at nucleotide position 178 of HPV-16 E6 gene in 10 cases,the mutation rate was 50%; For HPV-16 E7 gene, the mutations were found at nucleotide position 647 in 10 cases; the mutation rate was 50%. Phylogenetic analysis showed that Asian (As) variants of HPV-16 were predominated in Yunnan, China. None of African-1, African-2 variants of HPV-16 was found in this region.