ASSOCIATION OF XRCC1 GENE POLYMORPHISM AND THE RISK OF LUNG CANCER IN NORTH-INDIAN SUBCONTINENT KASHMIR VALLEY: A POPULATION BASED CASE –CONTROL STUDY.

Gousia Qayoom Mir, *Bashir Ahmad Ganai, Haamid Bashir, Shugufta Sheikh, Abdul Gani Ahanger, Akbar Masood

ABSTRACT

Background: The x-ray cross-complementing group 1 (XRCC1) is mainly involved in base excision repair (BER) of DNA repair pathways. Polymorphism of DNA repair gene XRCC1 has been identified and it is possible that this polymorphism may affect DNA repair capacity and thus modulate cancer susceptibility. We investigated the relationship between the codon 194 polymorphism in XRCC1 gene and lung cancer risk in male smokers. Method: A population based case-control study of 130 lung cancer patients and 130 healthy control subjects (Individually matched on age and gender) in a Kashmiri population was conducted in Tertiary care super specialty Hospital of Kashmir valley Sheri-Kashmir Institute of Medical Science (SKIMS). XRCC1 (codon 194) genotype was identified using Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. Result: We observed a significantly higher risk of lung cancer among cases who were carriers of the variant genotype Trp/Trp (homozygous mutant) [O.R = 2.43, 95%CI = 1.32 - 4.47, P = 0.006] as compared with homozygous wild genotype Arg/Arg. Our result suggested that the risk for the disease increases significantly as the number of Trp allele increased [OR = 2.31, 95% CI = 1.47 – 3.64, P = 0.0003]. Conclusion: Our study revealed that cases, especially smokers with homozygous variant genotype Trp/Trp tend to be more fragile and susceptible to lung cancer [OR = 2.85, 95% CI = 1.27 – 6.41, P = 0.01], as compared to non-smokers [OR = 2.0, 95% CI = 0.73 – 5.43, P = 0.26] and hence may help in identifying individuals at risk in Kashmiri population.

Keywords: XRCC1, Polymorphism, Lung cancer, PCR-RFLP, Kashmir, India etc.