The relationship between −330 interleukin-2 gene polymorphism and its plasma levels in patients with alopecia areata

Abstract

Background: Alopecia areata (AA) is an autoimmune, dermatological, chronic, inflammatory disease that attacks hair follicles and causes hair loss. Hair loss usually occurs on the scalp, but it can also affect the beard, eyebrows, and other areas of the body. Interleukin-2 (IL-2) is a cytokine that contributes to the regulation of the immune system and is classified as a proinflammatory factor. IL-2 is an autocrine secretary element produced from activated T-cells, exhibiting growth factor characteristics. Objective: The objective of this study was to investigate the effect of the −330 IL-2 gene polymorphism (rs2069762) on plasma IL-2 levels in Iraqi patients with AA. Materials and Methods: In this study, 100 patients with AA and 100 ethnicity-, age-, and sex-matched healthy controls were selected. Blood samples of all individuals were collected in EDTA tubes. The restriction fragment length polymorphism–polymerase chain reaction method was applied to determine various alleles and genotypes in these individuals. Plasma concentration of IL-2 was measured in all the samples using human IL-2 kit. Results: The frequency of −330 G/T IL-2 genotype was higher in patients with AA compared to normal individuals. Accordingly, the plasma levels of IL-2 were significantly higher (P < 0.0090) in patients when compared to the control group. Conclusion: In case of patients with AA, the −330 G/T IL-2 genotype is associated with higher plasma levels of IL-2.

Keywords

• −330 interleukin-2 polymorphism
• alopecia areata
• hair loss
• interleukin-2