Metallothionein 2A genetic polymorphism and its correlation to coronary heart disease.

OBJECTIVE To investigate the gene polymorphism of metallothionein 2A (MT2A)-838G/C and its correlation to coronary heart disease in the Han population of Jiangsu, China. PATIENTS AND METHODS The MT2A-838G/C was examined in 287 patients with coronary heart disease (CHD group) and 226 healthy controls (control group) by using mono-labeled fluorescent probes. Meanwhile, relevant variables of all subjects were measured, including blood lipid and glucose profiles and body mass index (BMI). The extent of the coronary artery disease was evaluated based on Gensini's coronary artery scoring method. RESULTS Three distinct genotypes were identified. The highest frequency was observed for genotype GG, followed by genotype GC and CC. There were statistically significant differences in the genotype and allele frequency distribution of the MT2A gene-838G/C polymorphism between the CHD and the control group (p < 0.05). The allele frequency of MT2A-838C in the CHD patients were higher than that in the healthy controls (31.4% vs 24.6%, p = 0.016). The CHD risk in C allele carriers (including genotype GC+CC) was 1.562 folds as high as in GG allele carriers (OR = 1.562, 95% confidence intervals (CI): 1.099-2.218, p = 0.013). According to the results of logistic regression analysis, the C allele was an independent risk factor for CHD (p < 0.05). Gensini's coronary artery disease score were higher in C allele carriers than in non-C allele carriers (p < 0.05). CONCLUSIONS The gene polymorphism of MT2A-838G/C is correlated to CHD. The C allele might be a CHD-susceptible gene and might also have an effect on the extent of coronary artery disease.