The significance of interleukin 4 (IL-4) (590-C/T) gene polymorphism in Iraqi patients with type 2 diabetes mellitus: A case-control study

One of well knows ant-inflammatory cytokines is Interleukin 4 (IL-4). It plays major roles in the control of immune responses at various levels. It is involved in the proliferation of activated B and T cells, inhibition of type 1 T helper differentiation, and promotion of type 2 T helper cell differentiation, control of B cell maturation (10–13). Moreover, it is involved in the growth, apoptosis, proliferation, and maturation of other hemopoietic and nonhemopoietic cells (14). Previous studies have investigated its role in allergic and autoimmune disorders (14–17). The gene for IL-4 is located at chromosome 5 within the long arm and possesses four exons (18). Several authors have shown a possible association of IL-4 gene polymorphism to a number of clinical disorders such as multiple sclerosis, atopic dermatitis, rheumatoid arthritis, and asthma (19–21). IL-4 gene polymorphism has been linked to type 1 diabetes mellitus, but we in the current study aimed at investigating the significance of IL-4 590C/T (rs2243250) gene polymorphism in relation to type 2 diabetes and its long term complications. This study was aimed to assess the significance of IL-4 590C/T (rs2243250) gene polymorphism in relation to type 2 diabetes and its long term complications. The present case-control study was carried out at the diabetes center in Al-Diwaniayh Teaching Hospital, Al-Diwaniyah Province, Iraq. The study started in January 2019 and ended on July 2019. The study included 32 types 2 diabetes mellitus patients and 47 apparently healthy control subjects. Five ml sample of venous blood (antecubital vein) was obtained for the purpose of PCR analysis of IL-4 (590-C/T) gene polymorphism. The results of currents study revealed that the distribution of patients with type 2 diabetes was 21 (65.6%), 9 (28.1%) and 2 (6.3%) as CC, CT, and TT genotypes; whereas, the distribution of control subjects was 33 (70.2%), 10 (21.3%) and 4 (8.4%), as CC, CT, and TT genotypes. There was no significant difference in the frequency distribution of diabetic patients and control subjects according to IL-4rs2243250 genotype (P = 0.757). IL-4rs2243250 genotype polymorphism was not significantly correlated to retinopathy, nephropathy, neuropathy, CVA, IHD and dyslipidemia (P > 0.05), IL-4 IL-4rs2243250 genotype polymorphism is neither associated with type 2 diabetes mellitus nor is linked to its long term microvascular and or macrovascular complications.