Polymorphisms in Turkish population

The association of OGG1 Ser326Cys polymorphism and urinary 8-OHdG levels with lung cancer susceptibility: a hospital-based case-control study in Turkey.

Faculty of Pharmacy, Department of Toxicology, Gazi University, Ankara, Turkey. bensuka@gmail.com

High incidence and poor prognosis of lung cancer make it a major health problem worldwide. Although smoking is a major cause of lung cancer, only some smokers develop lung cancer, which suggests that there is a genetic predisposition in some individuals. 8-OHG is an important oxidative base lesion and may elevate due to cancer and smoking. It is repaired by 8-hydroxyguanine DNA glycosylase 1 (OGG1), which has several polymorphisms. Although the Ser326Cys polymorphism is consistently associated with a range of cancers, findings about this polymorphism and lung cancer risk are contradictory. To date, no study has examined this association in the Turkish population. We conducted a case-control study to investigate the association between OGG1 Ser326Cys polymorphism and the risk of lung cancer using PCR-RFLP. We also evaluated gene-smoking interaction and excretion of urinary 8-OHdG. Our results suggest that the OGG1 Ser326Cys polymorphism is not a genetic risk factor for lung cancer, and that the heterozygous genotype is associated with a significantly reduced risk for lung cancer. The levels of 8-OHdG did not correlate with the polymorphism and smoking. Larger association studies are needed to validate our findings, and mechanistic studies are needed to elucidate the underlying molecular mechanisms of this association.