Genetic Influences on HPV infection status in Korean women

Abstract

Human papilloma virus (HPV) infection is a sexually transmitted infection (STI) and is a well-established cause of uterine cervix cancer. Although previous studies have reported that hosts genetic polymorphism is associated with HPV infection, it is not well understood whether host susceptibility is a true risk factor. This study aimed to assess the overall genetic contribution to HPV infection status, the first event in the natural course of carcinogenic infection, in a twin-family cohort in Korea. Between 2006 and 2009, cervical smears were obtained from Papanicolaou (Pap) tests of 912 women (mean age 48

142 monozygotic twin (MZ) pairs) from 260 families that were participants of the Healthy Twin Study. HPV infection was diagnosed using two different PCR amplifications of partial sequences of HPV. To investigate the correlation between HPV infection status of HPV types and environment factors, we used Spearmans correlation analysis. The association with HPV infection status and several environment factors was analyzed using multiple regressions with mixed model. Genetic factor which has effects on HPV infection status by HPV types was analyzed by two methods

Intraclass Correlation Coefficients (ICC) and heritability. Heritability was calculated by variance component method. According to results of this study, correlation between HPV infection status of HPV types and environment factors, which is an important indicator of HPV infection, was oral contraceptive use. Although several environment factors were not associated with HPV infection status, genetic factor has mild association with HPV infection status. Concordance to discordance ratio within pairs was highest among MZ (3 to 19). This could be confirmed by ICC analysis using tetrachoric correlation coefficient and heritability analysis. Genetic components were estimated by heritability that was 0.24-0.31 for overall HPV infection, and when analyses were performed by the viral type

0.51-0.54 for lower risk strains and not significant for high-risk strains. Our findings suggest that HPV infection status is influenced by a hosts genetic factors, viral genotype as well.