The Single Nucleotide Polymorphisms (rs1292037 and rs13137) in miR-21 Were Associated with T2DM in a Chinese Population

Background: Insulin receptor (INSR), insulin receptor substrate (IRS) and glucose trans-porter 4 (GLUT4) play important roles in the insulin resistance pathway. The microRNA (miRNA or miR) involved in INSR, IRS or GLUT4 could be associated with the develop-ment of type 2 diabetes (T2DM). Methods: The aim of this study was to investigate the association of T2DM with 12 single nucleotide polymorphisms (SNPs) in 7 miRNAs (miR-195, miR-126, miR-144, miR-155, miR-21, miR-93 and miR-222) involved in the insulin resistance pathway. A total of 1593 subjects with T2DM and 1656 nondiabetic subjects were genotyped. Then, the associations of these SNPs with the development of T2DM and individual metabolic traits were eval-uated, such as fasting plasma glucose (FPG) and glycosylated haemoglobin (HbA1C). Results: Our data showed that the C allele of rs1292037 in miR-21 could increase the risk of developing T2DM (P = 0.002, OR = 1.17; 95% CI: 1.06-1.29). In addition, the T allele of rs13137 in miR-21 could be a risk factor for T2DM (P = 0.003, OR = 1.16; 95% CI: 1.05-1.28). According to inheritance mode analysis, compared with the T/T-T/C genotype, the C/C genotype of rs1292037 showed a risk effect in T2DM in the recessive mode (P = 0.001, OR = 1.35; 95% CI: 1.13-1.63). For rs13137, compared with the A/A-A/T genotype, the T/T genotype also showed a risk effect in T2DM in the recessive mode (P = 0.001, OR = 1.35; 95% CI: 1.13-1.62). Moreover, in the nondiabetic group, compared with the rs78312845 A/G (FPG = 5.1771-0.488mmol/L; HbA1C = 5.1471-0.293%) and A/A genotypes (FPG = 5.1551-0.486mmol/L; HbA1C = 5.136 1-0.299%), the G/G genotype (FPG = 4.8871-0.482mmol/L; HbA1C = 4.9601-0.397%) was asso-ciated with lower FPG (P = 0.012 and 0.019) and HbA1C (P = 0.008 and 0.011). Conclusion: Our results revealed that rs1292037 and rs13137 in miR-21 were associated with T2DM susceptibility in a Han Chinese population. Moreover, the rs78312845 in miR-195 con-tributed to the level of FPG and HbA1C in nondiabetic group in the Han Chinese population.