Association analysis of ALOX5 gene polymorphisms with stroke risk: a case-control study in a Chinese Han population

Background: Stroke is a major cause of death and disability in the world. Genetic factors have been implicated in stroke risk but few have been reported. This study aimed to assess the association of ALOX5 gene polymorphisms and stroke risk in a Chinese Han population. Methods: We conducted a case-control study in ischemic stroke and its subtypes in 488 cases and 504 controls, all of Chinese Han ancestry. We selected 9 single nucleotide polymorphisms (SNPs) of the ALOX5 gene to test the association. All these SNPs were genotyped using Sequenom Mass-ARRAY technology. For each SNP, genotypic frequencies in controls were tested for departure from Hardy-Weinberg Equilibrium (HWE) using an exact test. A P-value of 0.05 was considered the threshold for statistical significance. We compared the allele frequencies of cases and controls using the chi-squared (chi(2)) test. Associations between the gene and the risk of stroke were tested using various genetic models (allele, dominant, and recessive) and analysis by SNP stats. Odds ratios and 95% confidence intervals (CIs) were calculated by unconditional logistic regression with adjustments for age and gender. Results: We identified that the SNP rs3740107 were associated with a decreased risk stroke in the recessive model (OR=0.51; 95% CI=0.28-0.91; P=0.02). Additionally, very strong linkage was found between rs6593482, rs3824612, rs2029253, rs7918542, rs7919239, rs1369214, and rs10900213; and between rs3740107 and rs3780914 by Haploview analysis. Conclusion: The present study suggested that gene polymorphisms in the ALOX5 gene may exert influences stroke susceptibility in a Chinese Han population.