Genetic association analysis between IL9 and coronary artery disease in a Chinese Han population.

Interleukin-9 (IL-9) plays important role in coronary artery disease (CAD). However, the exact relationship between them is not explored yet. Here, four tag SNPs covering IL9 (rs31563, rs2069868, rs2069870 and rs31564) were selected to conduct case-control association analyses in a total of 3704 individuals from Chinese Han population (1863 CAD vs 1841 control). Results showed that: first, rs2069868 was associated with CAD combined with hypertension (P = 0.027); second, IL9 haplotype (CGAT) was associated with CAD (P = 0.035), and the combination genotype of "rs31563_CC/rs31564_TT" would remarkably decrease the risk of CAD (P = 0.001); third, significant associations were found between rs2069870 and decreased LDL-c levels and decreased total cholesterol levels, and between rs31563 and increased HDL-c levels (P < 0.05). Therefore, we conclude that IL9 might play a causal role in CAD by interacted with CAD traditional risk factors, which might confer a new way to improve the prevention and treatment of CAD.