Polymorphism of HPV-16 type L2 genes from cervical carcinoma biopsies in southern Xinjiang Uygur women
Objective To study the mutations of HPV-16 type L2 genes of cervical carcinoma biopsies from Uygur women in southern Xinjiang, and to analyze the changes of L2 protein function. Methods The tissue DNA was extracted from cervical carcinoma biopsies. HPV-16 L2 genes were amplified by PCR, HPV-16 type L2 genes were sequenced and analyzed. Results The positive rate of HPV-16 L2 was 84.21%(16/19). We sequenced DNA found some mutations in comparison with the previously published sequence of prototype HPV-16 L2. Some of the mutations changed the triplet codes, subsequently led to changes of amino acids. The mutations of all twelve HPV-16 L2 fragments formed seven patterns(XJL2-1 to XJL2-7) at nucleic acid level. Compare to HPV-16 prototype, their homology was 99.37% to 99.79%. The mutations of all twelve HPV-16 L2 fragments formed five patterns at amino acid level, among the mutations XJL1-1/2/3 was by 66.67% (8/12). Conclusion HPV-16 type L2 genes from cervical carcinoma biopsies had some mutations in Uygur women from southern Xinjiang, and formed several patterns as well as mainstream pattern. The mutations of L2 proteins changed its hydrophobicity and antigenicity. The research suggested that the mutations of HPV-16 type L2 genes can explain HPV-16 phylogenesis and escaping from immune recognition.