title: Sequence variation analysis of HPV-18 isolates in southwest China.
abstract: Intratypic variations of HPV-18 are known to differ in the persistence of the infection, frequency of carcinogenesis and the progression of precursor lesions to advanced cervical cancer. This study was designed to analyze sequence variations of HPV-18 isolates in order to discover novel HPV-18 variants and to evaluate the variations among infected women in southwest China. Cervical biopsies from 56 HPV-18-positive women with cervical neoplasia were assayed by PCR amplification and sequencing of all eight genes (E1, E2, E4, E5, E6, E7, L1, L2) of the HPV-18 genome. The most frequently observed variation was a C to G transversion at nucleotide 287 of E6, which was found in 48.2% of samples. Analysis of E7 revealed only one specimen as having sequence variations. In addition, we have identified several novel variations: A551C in E6, G6906A in L1, and C4915T and C5147A in L2. The mutations in E6 and L2 are silent, while the E7 mutation results in a single amino acid change. This study complements and expands on previous descriptions of HPV-18 variants. The sequence variation data presented here provides a foundation for future research on HPV-induced oncogenesis and may prove valuable for developing diagnostic probes and in the design of HPV vaccines for targeted populations.
authors: Bio-resource Research and Utilization Joint Key Laboratory of Sichuan and Chongqing, Institute of Medical Genetics, College of Life Science, Sichuan University, Chengdu, People's Republic of China.
authors: Mengjie
authors: M
authors: Shen
authors: Xianping
authors: X
authors: Ding
authors: Tianjun
authors: T
authors: Li
authors: Gangyi
authors: G
authors: Chen
authors: Xiao
authors: X
authors: Zhou
mesh_terms: D002681:China; D004279:DNA, Viral / Q000235:genetics*; D005260:Female; D052161:Human papillomavirus 18 / Q000235:genetics*; D006801:Humans; D066298:In Vitro Techniques; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA / Q000379:methods; D002583:Uterine Cervical Neoplasms / Q000382:microbiology*
chemical_list: D004279:DNA, Viral