CHRNA5 rs16969968 Polymorphism Association with Risk of Lung Cancer - Evidence from 17,962 Lung Cancer Cases and 77,216 Control Subjects

Background: Genetic studies have shown a possible relationship between the rs16969968 polymorphism inCHRNA5 and the risk of lung cancer. However, the results have been conflicting. Thus we rigorously conducteda meta-analysis to clarify any association. Materials and
Methods: A total of 10 case-control studies involving17,962 lung cancer cases and 77,216 control subjects were analysed. Odds ratios (ORs) with 95% confidenceintervals (CIs) were used to measure the strength of the association.
Results: We found the CHRNA5 rs16969968polymorphism to be associated with the risk of lung cancer (AA vs GG: OR=1.60, 95%CI=1.51-1.71). On stratifiedanalysis by smoking status, a statistically significant increased risk was observed in the smoking group (AA vsGG: OR=1.80, 95%CI=1.61-2.01). However, this polymorphism was not associated with lung cancer risk inAsians (AA vs GG: OR=0.95, 95%CI=0.35-2.59), whereas it was linked to increased risk of lung cancer amongCaucasians (AA vs GG: OR=1.65, 95%CI=1.55-1.76).
Conclusions: Our meta-analysis provided statisticalevidence for a strong association between rs16969968 polymorphism and the risk of lung cancer, especially insmokers and Caucasians. Application of this relationship may contribute to identification of individuals at highrisk of lung cancer and indicate a chemoprevention target.