The muscle Ras (MRAS) gene polymorphisms have been reported to be associated with coronary artery disease (CAD) in white Europeans. The aim of this study was to ascertain the role of MRAS gene polymorphisms in conferring susceptibility to CAD, and to explore the effect on severity of CAD in Chinese population. We genotyped 5009 Chinese individuals (2466 CAD cases and 2543 controls) for eight single nucleotide polymorphisms (SNPs) around MRAS and used logistic regression analysis to determine whether they were associated with CAD. The association of the SNP loci on the severity of CAD was analyzed using a logistic and linear regression analysis, respectively. Our results revealed that an intron SNP, rs1199337, tends to be marginally associated with CAD as previously reported in Caucasians (nominal P = 0.01, OR 1.10,95% CI 1.01-120). However, this association did not retain statistically significant levels after applying Bonferroni's correction for multiple testing (corrected P = 0.08). There was no significant association between other loci and CAD (nominal P > 0.05). We did not observe any significant association between the SNPs and severity of CAD (all P values > 0.05). From the above results, the MRAS gene loci might have a minor effect in conferring susceptibility to CAD in Chinese population. (C) 2015 Elsevier B.V. All rights reserved.