Association Between IFN-γ Gene Polymorphisms and IgA Nephropathy in a Chinese Han Population

IFN-γ was reported to be involved in the development and progression of Immunoglobulin A nephropathy (IgAN), however, few studies have investigated the association between IFN-γ polymorphisms and IgAN. Therefore, we performed a case-control study to assess the association between IFN-γ polymorphisms and the risk of IgAN.

Sequenom MassARRAY was used to genotype two SNPs (rs1861494 and rs2430561) in 351 patients with IgAN and 310 healthy controls. Associations were evaluated as odd ratios (OR) with 95% confidence intervals (CI).

No association was found between IFN-γ rs1861494 and IgAN risk or clinical parameters. For rs2430561, the AA genotype was more common in patients with IgAN, compared with controls (AT vs. AA: OR = 0.57, P = 0.035). IFN-γ-rs2430561 T allele may be a protective factor for IgAN susceptibility (T vs. A: OR = 0.59, P = 0.04). Subgroup analysis based on clinical features revealed no significant association between rs2430561 polymorphism and clinical data such as gender, 24-h urine protein, blood pressure, Oxford classifcation and estimated glomerular fltration rate. IgAN patients had a higher IFN-γ serum level than healthy controls and patients with rs1861494 AA genotype had a higher IFN-γ serum level compared with those with AG/GG genotypes.

IFN-γ polymorphisms may be involved in the development and progression of IgAN.