Predictive role of chromosome 9p21.3 polymorphisms and their association with family history of coronary heart disease in patients with myocardial infarction

Aim. To investigate the association between single-nucleotide polymorphisms (SNPs) rs10757278 and rs1333049 of the 9p21.3 locus and family history of coronary heart disease (CHD) in myocardial infarction (MI) patients. Material and methods. The MI group (n=243) and the control group (n=280) were comparable by such parameters as age, gender, arterial hypertension, diabetes mellitus, hypercholesterolemia, overweight and obesity, abdominal obesity, and smoking history. However, the groups were significantly different in terms of family history of CHD (p=0,004). Genome DNA was extracted from venous blood using the phenol-chloroform extraction method. The SNPs rs10757278 (9p21.3) and rs1333049 (9Sp21.3) were tested using real-time polymerase chain reaction (PCR) and the AB 7900HT device, according to the producer's protocol (TaqMan probes, Applied Biosystems, USA). Results. A statistically significant association between MI and the CC rs1333049 genotype or the GG rs10757278 genotype was observed in the whole study sample and separately in men and women. The MI odds ratio (OR) for carriers of the CC rs1333049 genotype was 2,02(95% confidence interval, Cl, 1,32-3,08) in the whole sample, 1,91 (1,11-2,95) in men, and 2,91 (1,22-6,91) in women. For carriers of the GG rs10757278 genotype, respective OR values were 1,98 (1,30-3,02), 1,77 (1,08-2,87), and 2,94(1,26-6,87). Among participants without CHD in family history, OR for the CC rs1333049 genotype (1,92,95% Cl 1,16-3,16) and the GG rs10757278 genotype (1,82, 95% 01 1,10-3,00) were comparable for those among MI patients with CHD in family history (respective OR 2,19 (1,28-3,75) and 2,23(1,31-3,81)). Conclusion. For the first time in Russia, the association between MI-related polymorphisms of the 9p21.3 chromosome and family history of CH D was analysed. Two SNPs (rs1333049 and rs10757278) of the 9p21.3 locus predicted MI risk independently from either conventional risk factors or CHD in family history.