Analysis on the Polymorphisms of Site RS4977574, and RS1333045 in Region 9p21 and the Susceptibility of Coronary Heart Disease in Chinese Population

Background: Rs4977574 (A > G) and Rs1333045 (C > T) are both single nucleotide polymorphisms (SNPs) related with coronary artery disease, locating on chromosome 9p21.3. The study aimed to identify the correlation between rs4977574 and rs1333045 polymorphism genotypes and coronary heart disease (CHD) in a Chinese population.

Methods: Blood samples were collected from 855 subjects. A case-control study was used in this experiment, and 598 cases in the CHD group and 257 subjects in the control group were enrolled. Genotyping was identified by the Agena MassARRAY system. Statistical analysis was conducted by SPSS (Ver 16.0) and plink (Ver. 1.07, Shaun Purcell). Haplotype analysis was performed using Haploview software.

Results: Association analysis by plink indicated a significant difference in the allele distribution for single nucleotide polymorphisms between cases and controls (rs4977574 P = 0.003, rs1333045 P = 0.035). Fisher's exact test by plink proved that allele G may be associated with a higher risk of CHD (P = 0.003, odds ratio (OR) = 1.371) and the T allele was likely to reduce the risk of coronary events (P = 0.035, OR = 0.798). The serum levels of apolipoprotein A (ApoA) were higher in subjects with the AG + AA genotype of rs4977574 compared to those with the GG genotype (P = 0.028). In the dominant model of rs1333045, the levels of ApoA were higher and LDL levels were lower in the TC + TT genotype than in the CC genotype.

Conclusions: The present study examined the association between the 9p21 chromosome rs4977574 and rs1333045 polymorphism genotypes and CHD in a population of Chinese patients. The G allele of rs4977574 and the C allele of rs1333045 are the susceptibility sites of CHD.