Polymorphism on Chromosome 9p21.3 Is Associated with Severity and Early-Onset CAD in Type 2 Diabetic Tunisian Population

Multiple association studies found that the human 9p21.3 chromosome locus is a risk factor for atherosclerosis. The purpose of this study was to investigate the association of the severity and early-onset of coronary artery disease with variant rs1333049 on chromosome 9p21.3 polymorphism and the impact of this variant on cardiovascular risk factors in type 2 diabetic patients. The study population consisted of a control CAD group (101 patients) and 273 consecutive type 2 diabetic patients. Severity and extent of coronary atherosclerosis were scored numerically using the Gensini scoring system. The diabetic population was divided into three groups according to Gensini score: Group 1: no stenosis; Group 2: moderate CAD; Group 3, severe CAD. The homozygous CC genotype of rs1333049 was significantly associated with CAD in Group 2 (OR: 1.36; p = 0.02) and Group 3 (OR: 5.77, p < 0.001) compared to Group 1 (OR: 0.18; p = 0.2) and control group (OR: 0.22; p = 0.21). Among diabetic patients with early-onset CAD, CC genotype carriers had significantly higher Gensini scores than non-CC genotype carriers (49 ± 21.3 versus 14.87 ± 25.22; p < 0.001). The homozygous CC genotype of rs1333049 confers a magnified risk of early-onset and severe CAD in type 2 diabetic Tunisian population.