The Study of the Association in between CHRNA 5 Gene Polymorphism (rs16969968) and Chronic Obstructive Pulmonary Disease

Background and Aim: Chronic obstructive pulmonary disease (COPD) is a complex, progressive inflammatory disorder of the respiratory system that predominantly affects the distal airways and is characterized by irreversible destruction of lung parenchyma. Genetic susceptibility plays an important role in the pathogenesis of COPD. The objective of this study was to examine the relationship between COPD and CHRNA5 gene polymorphism (rs16969968). Methods: A total of 200 subjects were enrolled, including 100 diagnosed COPD cases and 100 age- and sex-matched healthy controls. Genotyping of the single nucleotide polymorphism (SNP) rs16969968 was carried out using allele-specific polymerase chain reaction (AS-PCR) with specific primers. Allele and genotype frequencies were measured, and statistical analysis was conducted using SPSS software to assess the association between CHRNA5 gene polymorphism and COPD risk. Results: The distribution of CHRNA5 (rs16969968) genotypes did not show a statistically significant association with COPD. The AA genotype was observed in 6% of controls and 15% of COPD cases, the heterozygous AG genotype in 39% of controls and 43% of COPD patients, and the homozygous GG genotype in 55% of controls and 42% of COPD cases. The wild-type G allele was found in 149 (74.5%) of controls and 127 (63.5%) of COPD patients, while the A allele was found in 51 (25.5%) of controls and 73 (36.5%) of COPD cases. Statistical analysis revealed no significant difference in allele frequencies (p = 0.157). Although genotype distribution showed a trend toward significance (p = 0.055), it did not reach the conventional threshold (p < 0.05). Odds ratio analysis revealed an OR of 1.688 (p = 0.066), suggesting a possible increased risk among A allele carriers. Conclusion: This study did not demonstrate association between the CHRNA5 rs16969968 polymorphism and COPD. However, odds ratio analysis indicated a possible 1.7-fold increased risk of COPD among carriers of the A allele, suggesting a potential role of CHRNA5 variants in disease susceptibility. Larger studies with diverse populations are warranted to further clarify the contribution of CHRNA5 variants to COPD risk.