Sequence polymorphism of human papillomavirus type 16 E7 in cervical cancer

Abstract

Abstract: Objective To explore the genetic polymorphism of E7 open-reading frame of human papillomavirus (HPV) type 16 in cervical cancer. Methods The types of HPV was identified by sequence analysis of the PCR product of HPV in cervical cancer tissues. HPV 16 gene fragment in the cervical cancer tissue was amplified by HPV-specific PCR with general consensus primers. Results The positivity rate of high-risk HPV types in 50 cases of cervical cancers was 78%. Mixed infection of HPV16 and HPV18 was found in 18 cases, and the infection with HPV16 alone occurred in 15 cases. HPV16 E7 was amplified from 25 out of the 34 cases positive for HPV16. A T-to-C change occurred in the 647th nucleotide in the viral nucleotide sequence, causing conversion of the Asn codon of E7 gene into a Ser codon. Conclusions The most frequently observed substitution in HPV16 E7 open reading frame occurs in the discrete regions of 647-846, and some substitutions result in the same-sense mutation. The hot-spot mutation of HPV16 E7 in cervical cancers in Guangdong Province occurs at the nucleotide 647 and 846 in the DNA sequence.

CLC Number:

LIU Xin, LIU Guo-bing, PANG Zhan-jun, XING Fu-qi. Sequence polymorphism of human papillomavirus type 16 E7 in cervical cancer[J]. Journal of Southern Medical University, 2005, 25(10): 1272-1275.

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