Objective: To study the relationship of tumor necrosis factor-alpha (TNF-α)-308G/A gene polymorphisms with Henoch-Schonlein purpura nephritis (HSPN) in children.
Methods: Using the direct DNA sequencing method, polymorphisms in the TNF-α promoter region (-308) were genotyped in 110 Han children with Henoch-Schonlein purpura (HSP group), including 52 children with nephritis and 58 children without nephritis. Plasma TNF-α levels were measured using ELISA. Ninety ethnically matched healthy children were used as the control group.
Results: There were no significant differences in the polymorphisms of TNF-α (-308G/A) between the HSP and control groups (P>0.05). The GA genotype (29% vs 10%) and A allele frequency (18% vs 7%) in HSP children with nephritis (HSPN) were more common than in those without nephritis (P<0.05). Plasma TNF-α levels in HSPN children with GA+AA genotype (7.1±2.3 pg/mL) were significantly higher than those with GG genotype (5.7±1.5 pg/mL) (P<0.05).
Conclusions: TNF-α-308GA genotype and A allele may contribute to the increased risk for the development of nephritis in children with HSP.