Genetic Variations of CHRNA5 Gene Correlated to High Risk of Lung Cancer in Iranian Patients

Lung cancer is one of the most common malignant tumors and leading cause of cancer death that become a major public health problem worldwide. It appears to result from interactions between genetic susceptibility of the individual and risk factors in the environment. Genome wide studies have reported an association between the chromosome 15 region (15q25) and lung cancer risk and smoking habit. The region, spanning 203 kb, contains six genes including acetylcholine nicotinic receptor subunit α5 gene (CHRNA5) that might be good candidates for lung cancer risk. The strong linkage disequilibrium in this region has led to the identification of several single nucleotide polymorphisms (SNP) showing significant association with lung cancer risk. A particularly interesting variant in this locus is the single nucleotide polymorphism that lies in the fifth exon of CHRNA5 (rs16969968). This variant encodes a change from an aspartic acid to an asparagine residue at amino acid position 398 (D398N).In this case-control study, 89 patients with lung cancer and 90 control individuals to examine the association between polymorphism (rs16969968) and the risk of lung cancer, using PCR- RFLP and sequencing were studied. The results of this study indicated no significant association between this polymorphism and lung cancer risk in the population studied (OR = 1.26, 95% CI = 0.68-4.1, P > 0.05).Unlike previous studies, by examining the results of this study, no relationship between polymorphism (rs16969968) and risk of lung cancer was observed, probably due to small sample size or different spread of polymorphisms in different populations

کلیدواژه ها:

lung cancer ، polymorphism ، CHRNA5 ، nicotine