Cytokine Gene Polymorphisms in Chinese Children with Idiopathic Nephrotic Syndrome

Background: Cytokines play a role in the progression of idiopathic-nephrotic syndrome (INS). Objectives: To investigate the association of different cytokine genes polymorphisms with INS incidence and response to steroid therapy in Chinese children. Methods: 182 children with INS and 100 healthy controls were enrolled in this study. Blood genomic DNAs were used to analyze20 single nucleotide polymorphisms (SNPs) in 8 cytokine genes includingIL-21, IL-18, IL-6, IFN-γ, IL-4, IL-10, IL-17F, IL-17A d by multi-PCR with next-generation sequencing. Results: Among 182 children with INS, 89 (48.6%) were steroid-sensitive (SS), 73 (39.9%) were steroid-dependent (SD) and 21 (11.5%) were steroid-resistant (SR). In 20 SNPs, IL-4-rs2243283 exhibited a significantly different genotype distribution between INS and the healthy controls (CC is a risk genotype: 66.5% of INS VS 51% of the control; OR=1.91, p=0.012). Patients carrying AG genotype (rs2275913, IL-17A) had a significantly higher risk of steroid-dependent response (69.1% of SD VS 46.4% of SS; OR=2.58, p=0.014). Similarly, patients carrying A allele of IL-10-rs1800872 (39.0% of SD VS 26.7% of SS; OR=1.76, p=0.018) and C allele of IL-10-rs1800896 (12.3% of SD VS 3.9% of SS; OR=3.44, p=0.004) had a higher risk of steroid-dependent response. However, none of these 20 SNPs showed a significant difference between SS group and SR group. Conclusion: Among the 20 cytokine gene SNPs, IL-4-rs2243283 might increase the susceptibility to INS in Chinese children; rs2275913 of IL-17A, rs1180972, and rs1800896 of IL-10 show association with the steroid -response in Chinese INS children.