Objective To explore the relationship between single nucleotide polymorphism(SNP) rs1333049 and susceptibility to coronary heart disease of permanently inhabited Yi ethnic people in frontier plateau area.

Methods Using the random number table method, 120 cases of permanently inhabited Yi ethnic patients of frontier plateau area in Diannan Central Hospital of Honghe Prefecture were selected as study objects, and were divided into coronary artery disease group and control group according to clinical diagnosis results, with 60 cases in each group. Peripheral venous blood was collected and rs1333049 genotype in 9p21.3 region of chromosomewas detected by TaqMan real-time fluorescence quantitative polymerase chain reaction (PCR). The frequency of genotypes (CC, CG, GG), frequency of allele (C, G) and gene amount were compared between the coronary artery disease group and the control group. The genotype frequency, allele frequency and gene amount of rs1333049 in coronary artery disease patients with different disease stages were analyzed. MultivariateLogistic regression analysis was used to explore the influencing factors of rs1333049 CG gene expression in patients with coronary heart disease.

Results The CG genotype frequency and CG gene amount of rs1333049 SNP locus in the coronary artery disease group were higher than those in the control group (P < 0.05). The CG genotype frequency and CG gene amount of rs1333049 SNP locus in patients with acute myocardial infarction in the coronary heart disease group were higher than those in the control group (P < 0.05). There were no significant differences in genotype frequency, allele frequency and gene amount of rs1333049 SNP locus in patients with unstable angina pectoris and stable angina pectoris in the coronary heart disease group when compared with those of the control group (P>0.05). CG gene amount expression of rs1333049 was associated with left main branch (LM)/left anterior descending branch (LAD) lesions in permanently inhabited Yi ethnic patients with coronary artery disease in the border plateau area (P < 0.05), but had no correlations with blood lipid indexes, fasting blood glucose (FBG), different disease stages of coronary heart disease, right coronary artery disease, lesion of left circumflex branch and the stenosis degree of each coronary artery (Gensini score) (P>0.05). Multivariate Logistic regression analysis showed that FBG (OR=1.55; 95%CI, 1.01 to 2.36), LM/LAD lesions (OR=1.87; 95%CI, 1.10 to 3.16) were independent influencing factors of rs1333049 CG gene expression in Yi ethnic patients with coronary heart disease in border and plateau areas (P < 0.05).

Conclusion The rs1333049 CG gene is a susceptibility gene for coronary heart disease in permanently inhabited Yi ethnic people in frontier plateau, while FBG and LM/LAD lesion are influencing factors for expression of rs1333049 CG gene.