DNA Repair Gene XRCC1 and XPD Polymorphisms and Gastric Cancer Risk: A Case-Control Study Outcome from Kashmir, India

Coding polymorphisms in several DNA repair genes have been reported to affect the DNA repair capacity and are associated with genetic susceptibility to many human cancers, including gastric cancer. An understanding of these DNA repair gene polymorphisms might assess not only the risk of humans exposed to environmental carcinogens but also their responses to different therapeutical approaches, which target the DNA repair pathway. In the present study, polymorphic variants of two DNA repair genes, XRCC1 Arg399Gln and XPD Lys751Gln, were chosen to be studied in association with gastric cancer susceptibility in the Kashmiri population. A total of 180 confirmed cases of gastric cancer (GC) and 200 hospital-based controls from Government Shri Maharaja Hari Singh Hospital, Srinagar, were included in the study. The genotyping for XRCC1 and XPD genes was carried out by polymerase chain reaction-restriction fragment length polymorphism. We found that tobacco smoking is strongly associated with GC risk (OR = 25.65; 95% CI: 5.49–119.7). However, we did not find any association of polymorphism of XRCC1 Arg399Gln (OR = 1.56; 95% CI: 0.32–7.82) and XPD Lys751Gln (OR = 0.46; CI: 0.10–2.19) with GC risk in the study population. The combination of genotypes and gender stratification of XRCC1 and XPD genotypic frequency did not change the results. Consumption of large volumes of salt tea was also not associated with gastric cancer risk. Polymorphic variants of XRCC1 Arg399Gln and XPD Lys751Gln are not associated with the risk of gastric cancer in the Kashmiri population. However, replicative studies with larger sample size are needed to substantiate the findings.