Variant on 9p21 is strongly associated with coronary artery disease but lacks association with myocardial infarction and disease severity in a population in Western India

Abstract

Background and aims: Coronary artery disease (CAD) is the leading cause of death worldwide, especially so in Indians. Recently, genome-wide studies have implicated SNPs in the 58 kb region of chromosome 9p21 to be associated with CAD. In the current study we evaluated the association of single nucleotide polymorphism (SNP) rs10757278 at the 9p21 locus with CAD in a population from Western India.

Methods: Genotyping for rs10757278 A/G was done by direct sequencing in 215 cases with confirmed CAD and 150 controls.

Results: A significantly higher frequency of the G allele was seen in cases as compared to controls (0.64 vs. 0.53). In the current study the G allele showed association with risk of CAD (OR 1.832 per G allele 95% 1.035-3.242, P 0.042; OR 2.452 GG vs. AA 95% 1.358-4.4431, P 0.004). Addition of the 9p21 allele to Framingham risk score (FRS) resulted in a shift of 17% of individuals from the low-risk category to the intermediate-low (>5-<10% 10-year risk) and 7% from intermediate-low to intermediate-high (>10-<20% 10-year risk) categories.

Conclusions: The rs10757278 G variant at the 9p21 locus is significantly associated with the risk of CAD in our population of Western India, similar to the observed trend in other populations; however, the association is much stronger in the present cohort and, considering the high propensity of Indians to develop CAD, it is an important marker even in terms of risk classification.