Association of the -2549 insertion/deletion polymorphism in the promoter region of vascular endothelial growth factor towards chronic obstructive pulmonary disease susceptibility and clinical factors in the North Indian population.

Chronic obstructive pulmonary disease (COPD) is a progressive respiratory disorder characterized by persistent inflammation, airway remodeling, and irreversible airflow limitation. Vascular endothelial growth factor (VEGF) plays a critical role in angiogenesis and exerts antiapoptotic effects on endothelial cells. The -2549 insertion/deletion (I/D) polymorphism in the promoter region of the VEGF gene has been reported to modulate gene expression and may influence disease susceptibility. This case-control study aimed to investigate the association between the VEGF -2549 I/D polymorphism and susceptibility to COPD, including its relationship with clinical parameters. A total of 100 COPD patients and 100 age- and sex-matched healthy controls were genotyped for the VEGF -2549 I/D variant using polymerase chain reaction following DNA extraction from peripheral blood samples. Chi-square tests were employed to assess allelic and genotypic frequencies, while logistic regression was used to analyze associations with demographic and clinical factors. The DD genotype was more prevalent among COPD patients, and differences were observed in lung function (FEV₁), COPD Assessment Test scores, and Global Initiative for Chronic Obstructive Lung Disease classification; however, these associations were not statistically significant after adjustment for confounders. Subgroup analysis showed variations in genotype associations among male subjects and smokers, although these findings were not statistically significant. Overall, these findings do not demonstrate a significant association between the VEGF -2549 I/D polymorphism and COPD susceptibility. The observed subgroup and clinical patterns may warrant further investigation in larger studies, particularly in genetically diverse populations.