BACKGROUNDReactive oxygen species are thought to contribute to the development of renal damage. The P22phox subunit of nicotinamide adenine dinucleotide phosphate (NAPDH) oxidase, encoded by the cytochrome b245a polypeptide gene, CYBA, plays a key role in superoxide anion production. We investigated the association of CYBA rs7195830 polymorphism with estimated glomerular filtration rate (eGFR) and the role it plays in the pathogenesis of chronic kidney disease (CKD) in a Han Chinese sample.

METHODSThe Gaoyou study enrolled 4473 participants. Serum levels of creatinine were measured and eGFR was estimated using the Chronic Kidney Disease Epidemiology Collaboration equations. The CYBA polymorphisms were genotyped. Then we investigated the association between eGFR and the rs7195830 polymorphism in the recessive model.

RESULTSThe AA genotype of rs7195830 was associated with significantly lower values of eGFR compared with the GG and AG genotypes ((102.76 ± 17.07) ml×min(-1)×1.73 m(-2) vs. (105.08 ± 16.30) ml×min(-1)± 1.73 m(-2)). The association remained significant in the recessive model after adjusting for age, gender, body mass index, smoking, hypertension, diabetes mellitus, uric acid, triglyceride, low density lipoprotein cholesterol and high density lipoprotein cholesterol (β=1.666, P=0.031). The rs7195832 AA genotype was an independent risk factor for CKD: eGFR <60 ml×min(-1)×1.73 m(-2) (odds ratio=3.32; 95% CI=1.21-9.13).

CONCLUSIONThe AA genotype of rs7195830 is independently associated with lower estimated glomerular filtration rate and is significantly associated with CKD.