Polymorphisms in the TNF-α and IL-10 gene promoters and risk of psoriasis and correlation with disease severity

•Increased frequency of GG genotype of IL-10-1082 in psoriatic patients.•Significant increase in the G allele of TNF-α-308 in psoriatic patients.•Serum TNF-α level significantly increased in psoriatic patients.•Serum IL-10 significantly decreased in psoriatic patients.

Several cytokines were assumed to play an essential role in the induction and the pathogenesis of psoriasis. The aim of this work was to investigate the role of TNF-α-308 and IL-10-1082 polymorphisms and their serum levels in the pathogenesis of psoriasis and determine their relation to disease severity. 110 Psoriasis patients and 120 healthy volunteers were genotyped for TNF-α-308 and IL-10-1082 polymorphism by polymerase chain reaction. Serum level of TNF-α and IL-10 were measured by ELISA. Our study demonstrated an association of IL-10-1082 polymorphism and psoriasis and between TNF α-308 polymorphism and psoriasis disease and severity. Serum TNF α increased in patients, while serum IL-10 decreased in patients with significant correlation between serum TNF-α and psoriasis severity. These results indicated that TNF-α-308 and IL-10-1082 polymorphisms imparted significant risk towards the development of psoriasis.