Chromosome 9p21.3 polymorphism in a Chinese Han population is associated with angiographic coronary plaque progression in non-diabetic but not in type 2 diabetic patients

BACKGROUND We sought to explore the association of variant rs1333049 on chromosome 9p21.3 with coronary artery disease (CAD) and angiographic plaque progression in non-diabetic and type 2 diabetic patients. METHODS Genotyping and quantitative coronary angiography (QCA) were performed in 2046 Chinese Han patients (1012 diabetic cases) undergoing coronary angiography; 430 of them received repeat angiographic studies at 1-year follow-up. RESULTS CC genotype at rs1333049 on chromosome 9p21.3 was associated with CAD (unadjusted OR 1.524, p = 0.001 and adjusted OR 1.859, p = 0.005, respectively). However, CC genotype had no magnified association with CAD in diabetic patients (OR 1.275, p = 0.150) compared with non-diabetic counterparts (OR 1.446, p = 0.020) after adjusting for conventional risk factors. During angiographic follow-up, non-diabetic patients (n = 280) had significant decrease in minimal lumen diameter and increase in percent diameter stenosis among the three genotypes (p = 0.005 and p = 0.038, respectively), demonstrating that CC or GC genotype carriers had a more severe plaque progression than GG genotype carriers. In patients with type 2 diabetes (n = 150), although plaque progression was more severe than that in non-diabetic counterparts, no relations existed between plaque progression and genotypes. Rs1333049 was an independent determinant of plaque progression for non-diabetic (OR 3.468, p = 0.004 and OR 4.339, p = 0.002 for GC and CC genotype, respectively) but not for diabetic patients (OR 0.529, p = 0.077 and 0R 0.878, p = 0.644 for GC and CC genotype, respectively). CONCLUSIONS This study demonstrates a significant association of homozygous CC genotype of rs1333049 on chromosome 9p21.3 with CAD in Chinese Han population. Rs1333049 polymorphism is an independent determinant for coronary plaque progression in non-diabetic but not in type 2 diabetic patients.