Impact of Polymorphisms of the Genes Encoding Angiotensin II-Forming Enzymes on the Progression of IgA Nephropathy

BACKGROUND/AIMS: Angiotensin II has been shown to play an important role in various renal diseases. Genetic polymorphisms of the renin-angiotensin system have been reported to be related to the clinical outcomes in immunoglobulin A nephropathy (IgAN). We investigated the association of polymorphisms of the genes encoding major angiotensin II-forming enzymes with the development and progression of IgAN among Korean patients. METHODS: A total of 261 IgAN patients and 300 healthy controls were studied. The polymorphisms of angiotensin-converting enzyme gene (I/D, A2350G) and chymase (CMA) gene (rs1800875, rs1800876) were determined. RESULTS: No significant difference was observed in the genotype and allele frequencies of the polymorphisms between IgAN patients and controls. The frequency of AA/AG genotypes of CMA rs1800875 and CC/CT genotype of CMA rs1800876 were significantly higher in patients with progressive disease course than in those with stable course (53.2 vs. 38.6%, p = 0.029; 89.6 vs. 78.3%, p = 0.031, respectively). In the Cox regression model with adjustment for clinical risk factors, CMA rs1800875 AA/AG genotypes remained an independent risk factor (hazard ratio 2.351; p = 0.001). CONCLUSION: Our results suggest that the CMA rs1800875 polymorphism is associated with the progression of IgAN in Korean patients.