Evaluation of relation between IL-4 and IFN-gamma polymorphisms and type 2 diabetes

ABSTRACT

Although, type 2 diabetes is the most frequent type of diabetes, its main cause is yet to be clarified. Several environmental and genetic parameters are believed to be involved in diabetes. It has also been established that cytokines play key roles in pathogenesis of diabetes. Expression of cytokines is different from person to person and in different societies. Several studies showed that polymorphisms of +874 of interferon-gamma [IFN-gamma] and -590 of interleukin-4 [IL-4] are associated with the regulation of expression of these genes. This study was aimed to find polymorphisms of these regions in type 2 diabetes patients. In this experimental study peripheral blood samples were collected from 160 type 2 diabetic patients and 160 healthy controls. DNA was extracted by salting out method. Polymorphisms of +874 of 1FN-gamma and -590 of IL-4 were analyzed by ARMS-PCR and RFLP-PCR. Our findings indicated that TT genotype of IFN-gamma was increased in type 2 diabetic patients compared to the control but difference was not significant. Our results didn't show any significant difference between IL-4 genotype in diabetic and healthy controls either. Our results suggested that TT genotype of IFN-gamma can be associated with diabetes. This association can be described by the fact that over expression of IFN-gamma shifts immune system to Th 1; therefore, pancreatic cells can be miscarried by immune cells