Background and purpose: Many epidemiological studies have investigated the relationship between p53 codon 72 polymorphism and cervical cancer risk, but the findings are still conflicting. In contrast, data are lacking on the relationship between XRCC1 polymorphism and cervical neoplasm risk. This community-based nested case-control study examined the association between genetic polymorphisms of p53 codon 72 and XRCC1 codons 194, 280, and 399 and cervical intraepithelial neoplasm (CIN) susceptibility in Taiwanese women.
Methods: Women living in Chiayi City, located in southwestern Taiwan, who had received Papanicolau (Pap) smear screening between October 1999 and December 2000 (n = 32,466) were included. Potential cases were women having lesions with cervical intraepithelial neoplasm II (CIN2) and over (> or = CIN2) reconfirmed by cervical biopsy. Potential controls (case:control = 1:2) were age matched (+/- 2 years) and residency matched women who had normal Pap smears. DNA samples were extracted from peripheral blood specimens and genetic polymorphisms of p53 and XRCC1 were determined by polymerase chain reaction-restriction fragment length polymorphism.
Results: In total, 100 cases [97 high-grade squamous intraepithelial lesion (HSIL) and 3 invasive cancer] and 196 controls had complete demographic and clinical questionnaire data and data of analysis of XRCC1 polymorphism, whereas only 99 cases and 193 controls had complete data for p53 polymorphism. The frequency of pro/pro, pro/arg, and arg/arg in p53 codon 72 in cases was 15% (15/99), 58% (57/99), and 27% (27/99) and in controls was 17% (34/193), 48% (92/193), and 35% (67/193), respectively, which was not significantly different. The frequency of arg/arg, arg/gln, and gln/gln in XRCC1 codon 399 in cases was 54% (54/100), 38% (38/100), and 8% (8/100) and in controls was 58% (114/196), 37% (73/196), and 5% (9/196), respectively, which was not significantly different. No associations were found between XRCC1 codon 194 and 280 genotypes and HSIL risk. The joint effect of p53 and XRCC1 polymorphisms remained insignificant.
Conclusions: Our data suggest that p53 codon 72 and XRRC1 codon 194, 280 and 399 genotypes do not influence CIN risk in the Taiwanese population.