Inflammatory system gene polymorphism and the risk of stroke: a case-control study in an Indian population

Sequence variations in genes involved in inflammation system are known to contribute to the risk of cardiovascular diseases (CVD) including stroke. In this study, we performed a genetic association study on the single nucleotide polymorphisms (SNPs) present in the genes CD14 (-159 C/T), TNFalpha (-308 G/A), IL-1alpha (-889 C/T), IL-6 (-174 G/C), PSMA6 (-8 C/G), and PDE4D (SNP83 T/C, respectively) in order to discern their possible role in the susceptibility to stroke in a North Indian population. These SNPs were previously found to be associated with CVD through their contribution to inflammation. A case-control design was used to examine 176 stroke patients (112 ischemic and 64 hemorrhagic stroke patients) and 212 unrelated healthy control individuals. After adjustment for the confounding risk factors, the IL-1alpha -889 T allele carriers (TT+CT) were found to be strongly associated with both forms of stroke (OR=2.56; 95% CI=1.53-4.29; P=0.0004). The CC genotype of PDE4D was found to be associated only with ischemic stroke (OR=2.02; 95% CI=1.08-3.76; P=0.03). None of the variants tested for the CD14, TNFalpha, IL-6, and PSMA6 genes found to confer risk for stroke in the study population. In conclusion, the -889 C/T and SNP83 T/C SNPs of the IL-1alpha and PDE4D genes, respectively, appear to be genetic risk factors for stroke in our study population.