RESUMO
BACKGROUND: Accumulating evidences have shown that miRNAs are directly or indirectly involved in a variety of biological processes, and closely associated with diverse human diseases, including cardiovascular diseases. SNPs locating within pri/pre-miRNA can affect miRNA processing and binding ability of target genes. MiR-27a, miR-26a-1 miR-100, miR-126 and miR-218 were reported to be associated with pathogenesis of myocardial infarction (MI). Here we aimed to evaluate the potential association of five polymorphisms in these pri/pre-miRNAs with individual susceptibility to MI in a Chinese Han population. METHODS: Genotyping was performed in 287 MI cases and 646 control subjects using polymerase chain reaction-ligase detection reaction (PCR-LDR) method. The association of these SNPs with MI risk was performed with SPSS software. RESULTS: In a logistic regression analysis, we found that AG heterozygote (OR = 0.40, 95% CI = 0.21-0.76, Pa = 0.005) or AA homozygote (OR = 0.40, 95% CI = 0.22-0.75, Pa = 0.004) of pre-miR-27a rs895819 had a reduced susceptibility to MI in comparison with GG homozygote. Similarly, a reduced risk of MI was detected when the AG and AA genotypes were combined (OR = 0.40, 95% CI = 0.22-0.74, Pa = 0.003). However, no significant association between pri-miR-26a-1 pri-miR-100, pri-miR-126 and pri-miR-218 polymorphisms and MI risk was observed under the allelic and established genetic models. Further stratified analysis of pre-miR-27a rs895819 revealed a more significant association of AG + AA genotypes with MI risk among younger, male and smoking subjects. Interestingly, AG and AA genotypes of the rs895819 polymorphism conferred about 0.17 mmol/L and 0.18 mmol/L increase in HDL-C levels compared to GG genotype. CONCLUSIONS: Our findings suggest that the pre-miR-27a rs895819 polymorphism is associated with MI susceptibility in the Chinese Han population, which probably due to influence the HDL-C levels.