The interleukin-1 family gene polymorphisms and Graves' disease

Genetic factors, including cytokine gene polymorphisms, are potential contributors to the pathogenesis of the Graves' disease (GD). We attempted in this study to determine the association between GD and the following polymorphisms in the interleukin-1 (IL-1) family genes: IL-1alpha (-889C/T), IL-1ss (-511C/T), IL-1ss (+3962C/T), IL-1R (Pst-1 1970C/T) and IL-1RA (Mspa-I 11100C/T). We studied 107 patients with an established diagnosis of GD and 140 healthy controls. Cytokine typing was performed by the polymerase chain reaction with sequence-specific primers assay. Genotype distributions among patients were in Hardy-Weinberg equilibrium for all polymorphisms. The frequency of the IL-1alpha -889T allele was significantly higher in patients than in controls (51.9% vs. 31.6%, OR=2.33, 95% CI=1.61-3.38; p<0.0001). The IL-1RA Msp-I 11100C allele was significantly more frequent in patients than in controls (50.0% vs. 22.9%, OR=3.38, 95% CI=2.29-4.97, p<0.0001). No significant associations were found for other polymorphisms. Although the IL-1 family has well-known roles in GD pathogenesis, the contributions of their genetic variations to the disease are unclear. In this study, we documented a highly significant association between GD and polymorphism in IL-1alpha and IL-1RA genes. Further studies in other populations are necessary to confirm our results.