Association of interleukin-4 polymorphisms with multiple sclerosis in southeastern Iranian patients

BACKGROUND AND OBJECTIVES: Immune system–related factors are important in the pathogenesis of multiple sclerosis (MS). Interleukin 4 (IL-4) as a helper T cell (2TH) cytokine is involved in the regulation of immune responses. Hence, this study was designed to explore the association between MS and polymorphisms in the -590 region of IL-4. DESIGN AND SETTING: A descriptive study at Rafsanjan University of Medical Sciences, Rafsnajan from September 2009 to August 2010. PATIENTS AND METHODS: Blood samples were collected from 100 MS patients and 150 healthy controls on EDTA precoated tubes. DNA was extracted and analyzed for IL-4 polymorphisms using restricted fragment length polymorphism in patients and controls. Demographic data were also collected by a questionnaire that was designed specifically for this study. RESULTS: We observed a significant difference in the C/C, T/C, and T/T genotypes of the -590 region of IL-4 between patients with MS and healthy controls (P<.001). CONCLUSIONS: We conclude that functional polymorphisms of IL-4 possibly play a crucial role in the pathogenesis of MS.