Interleukin-6 gene polymorphism in Iranian patients with systemic lupus erythematosus.

Interleukin 6 (IL-6) has been shown to be related to the pathogenesis of systemic lupus erythematosus (SLE). In the present study, the relationship between two polymorphisms in the promoter region of IL-6 gene at positions -572 G/C and -174 G/C and disease susceptibility in 401 Iranian patients with SLE was investigated using polymerase chain reaction-restriction fragment length polymorphism method. The genotype distribution and allele frequencies of IL-6 gene polymorphism at -174 position showed no significant difference between SLE patients and controls.