Association of HLA-G gene promoter haplotype with childhood IgA nephropathy in the Korean population

Jung, Hwan Hee; Hahn, Won Ho; Cho, Byoung Soo; Kim, Sung Do

Abstract

PURPOSE
IgA nephropathy (IgAN) is the most commonly occurring form of chronic glomerulonephritis in pediatric cases. Human leukocyte antigen (HLA) genes have been implicated in various inflammatory and autoimmune diseases. The present study was conducted to investigate the association between 2 single nucleotide polymorphisms (SNPs) of the HLA-G gene and childhood IgAN.
METHODS
The authors analyzed and compared HLA-G gene SNPs (rs1736936 and rs2735022) in 174 patients with childhood IgAN and in 438 healthy controls. In addition, IgAN patients were dichotomized and compared with respect to proteinuria (< and >4 mg/m2/hour), the presence or absence of podocyte foot process effacement, and the presence of pathologically early and advanced disease markers such as interstitial fibrosis, tubular atrophy, or global sclerosis.
RESULTS
No significant SNP frequency differences were observed for the HLA-G gene between IgAN patients and the control group. Moreover, no significantly associated SNP was observed with the presence of proteinuria, podocyte foot process effacement, or pathologically advanced markers. However, the haplotype, composed of rs1736936 and rs2735022, showed a significant association with the susceptibility to develop childhood IgAN (haplotype T/C: dominant model, P=0.049; haplotype C/T: recessive model, P=0.030).
CONCLUSION
Our results indicate that rs1736936 and rs2735022 as the HLA-G gene promoter haplotype might be associated with the susceptibility to develop childhood IgAN in the Korean population.