Lack of Association between Interleukin-8 Gene +781 C/T Polymorphism and Henoch- Schönlein Purpura in Childhood

Henoch–Schönlein purpura (HSP), a common allergic hemorrhagic disease, occurs frequently in children affecting kidney, joint and skin. While interleukin-8 (IL-8) plays an important role in inflammation, the association between IL-8 gene  C/ T polymorphism and HSP remains unclear. Interleukin-8, an important chemokine related to the initiation and amplification of acute inflammatory responses, has been reported to be involved in the pathogenesis of some autoimmune and inflammatory diseases. In this study, we aimed to investigate whether IL-8 gene  C/T (rs2227306) polymorphism has an influence on susceptibility and clinical manifestations of patients to HSP. This hospital-based case-control study comprised 192 patients with HSP and 202 healthy controls. The genotypes of IL-8 gene  C/T polymorphism were identified using PCR-TaqMan method. All genotype frequencies of both groups (patients and controls) conformed to the Hardy–Weinberg equilibrium. No significant differences in allele or genotype frequencies of IL-8 gene  C/T polymorphism were observed between patients with HSP and controls (p=0.98, χ2=0.000 and p=0.49, χ2=1.432, respectively). When patients were stratified for the presence of joint, gastrointestinal and renal manifestations, genotype frequencies of IL-8 gene polymorphism were found no statistically significant differences (p>0.05). Our findings do not support that IL-8 gene  C/T polymorphism has an effect on the susceptibility to HSP in Chinese children.