CORRELATION BETWEEN THE CD4 GENE POLYMORPHISM WITH TYPE 1 DIABETES MELLITUS IN THE IRANIAN POPULATION

Type 1 diabetes mellitus (T1DM) is an autoimmune disease in which T-cell mediated selective pancreatic β- cell destruction occurs. Half the risk of T1DM development is given by the HLA gene region while the remaining risk is assigned to non-HLA genes, probably those engaged in the formation of antigen interaction complex. The CD4 gene product, which is among the most prominent T-cell surface receptors with a key role in antigen processing, could be regarded as a strong candidate. We investigated the possible association of the CD4 gene polymorphism with T1DM using the candidate gene approach. The pyrimidine- rich pentanucleotide repeat polymorphism residing in the promoter region of the CD4 gene was studied. In the present study 92 Iranian T1DM patients and 108 healthy matched control individuals were screened by PCR technique. The analysis of our results shows the protective association of CD4*A3 (RR= 0.159, 95% CI: 0.036-0.707; Pc=0.025) and the susceptible role of CD4*A5 (RR= 7.379, 95% CI: 1.630-33.414; Pc=0.010) with T1DM. Our results suggest that the certain CD4 alleles are associated either negatively or positively with T1DM in the Iranian population.