Type 2 diabetes mellitus (T2DM) is chronic metabolic disorder manifested by increased blood glucose (hyperglycemia) due to pancreatic β-cell dysfunction and/or decreased sensitivity of peripheral tissue to insulin. T2DM is a multifactorial disease that may results from interaction of environmental and genetic factors.
A case–control study consisting of 400 T2DM patients in addition to 400 as control. Phenotyping as well as anthropometric data included body mass index BMI, fasting plasma glucose (FPG), serum total cholesterol, serum triglyceride, VLDL, LDL, HDL insulin levels and Homeostatic Model Assessment for Insulin Resistance HOMA-IR were estimated for the two groups. PCR–RFLP was used to carry out genotyping of CDKN2A/B gene (rs10811661 T>C and rs2383208 A>G) SNPs.
For rs10811661 SNP the genotype and allele frequencies of CDKN2A/B gene for T2DM and control subjects showed that the co-dominant model in patients with the homozygous (TT) was found to be significantly (OR 2.51, 95% CI 1.47–4.24, P 0.004) higher than those in control group. In contrast, the heterozygous genotype (TC) did not reveal this significance (OR 1.14, 95% CI 0.77–2.62, P = 0.13), ANOVA test for mean comparison of biochemical markers under the co-dominant model of rs10811661 SNP genotype in CDKN2A/B gene, revealed a significant difference for insulin (P < 0.0001) and HOMA-IR (P < 0.0001) in T2DM group as compared to control one; However (rs2383208) SNP did not show any significant association with T2DM and with the measured biochemical marker at any model.
CDKN2A/B gene rs10811661 SNP was implicated in T2DM pathogenesis in this sample of Iraqi population also it affects insulin level in those patients, whereas the rs2383208 SNP did not impact the disease.