LAUSR

PURPOSE Autoimmune diseases are a group of complex diseases localized in multiple organ systems, with a wide spectrum of symptoms and still unclear causes. The aim of the present study was to analyse a possible association of three autoimmune disabilities - Multiple sclerosis (MS), LADA diabetes and Graves' disease (GD) with single nucleotide polymorphism (SNP; rs1990760) in the IF IH1 gene (also known as a melanoma differentiation-associated protein 5 - MDA5) within the Polish population. An additional goal was also to look for a correlation between this polymorphism and different clinical patient-related factors. MATERIALS AND METHODS The study population consisted of four groups of 944 unrelated Polish origin Caucasian patients - 324 with GD, 171 with MS, 49 with LADA diabetes and 400 healthy subjects as a control group. The SNP analysis was performed using the allelic discrimination technique. RESULTS & CONCLUSIONS There were significant associations of risk T allel of the analyzed polymorphism with all studied autoimmune diseases (GDOR = 1.34, p = 7.02e-03; MSOR = 1.36, p = 2.17e-02; LADA - OR = 3.36, p = 8.73e-07). We also found that the frequency of CT and TT genotypes of the rs1990760 IFIH1 gene only in females (with LADA, GD, MS) was significantly higher than those in the female control group (47%, 41% vs 44%, 34%; p = 1.32e-03, p = 4.39e-04; OR = 2.08, 95%CI: (1.33-3.28), OR = 2.29, 95% CI: (1.44-3.65) respectively). Our research has shown significant differences regarding some clinical features (BMI, TRAb, TSH, HbA1C, anti-GAD antibodies) and age at the beginning of the studied autoimmune disabilities. This study showed an association of rs1990760 polymorphism in the IFIH1 gene in the development of GD, LADA diabetes and MS within the Polish population. To our knowledge, this is the first study to investigate the relationship between IFIH1 polymorphisms and the risk of the development of MS and LADA in Poland.