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

Abstract

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.