Tumor necrosis factor-alpha single nucleotide polymorphisms in juvenile systemic lupus erythematosus

Abstract

BackgroundJuvenile systemic lupus erythematosus (JSLE) is a multi-system autoimmune disorder of unknown origin. Given the importance of the contribution of pro-inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α), towards the pathogenesis of JSLE, this study was performed to assess TNFA gene polymorphisms in a case-control study. MethodsFifty nine patients with JSLE were enrolled in this study as case group and compared with healthy control subjects. The frequency of alleles, genotypes, and haplotypes of TNFA single-nucleotide polymorphisms (SNPs) at positions −308 and −238 were evaluated, using polymerase chain reaction with sequence-specific primers method. ResultsThe G allele at position −238 in TNFA promoter region was significantly more frequent in patients with JSLE than in the healthy controls (P value<0.001), while the frequency of A allele at the same position was significantly lower than controls. Furthermore, a significant positive association for G/G genotype at the same position was detected in patients’ group compared with control subjects (P value<0.001). The GA haplotype of TNFA (positions −308, −238) was significantly less frequent in case group than in controls (P value<0.001), while GG was the most frequent haplotype for TNFA in the patient group, compared to controls (P value<0.01). ConclusionsPro-inflammatory cytokine gene polymorphisms may influence susceptibility to JSLE. Particular TNFA gene variants are associated with JSLE and could be used as a genetic marker for susceptibility to JSLE.