Polymorphisms in NADPH oxidase CYBA gene modify the risk of ESRD in patients with chronic glomerulonephritis.

End-stage renal disease (ESRD) was defined as start of renal replacement therapy or death due to kidney disease. However, death due to acute kidney injury was not included. It typically occurs when chronic renal failure progresses to a point where the kidneys are permanently functioning at less than 10% of their capacity. Oxidative stress (OS) plays a crucial role in ESRD. Nicotinamide adenine dinucleotide phosphate (NADPH) is one of the most important enzymes during oxidative stress. Cytochrome b light chain (CYBA), encoded by a polymorphic gene, which is a critical component of the nicotinamide adenine dinucleotide (NADH)/NADPH oxidase system and plays an important role in electron transport and superoxide anion production, is located on chromosome band 16q24 and has six exons spanning almost 7.76 kb of genomic DNA. CYBA gene polymorphisms can influence the activity of NADPH oxidase. To evaluate the association between CYBA gene polymorphisms and ESRD, we genotyped five CYBA polymorphisms using TaqMan allelic discrimination assay on DNA samples from 306 healthy controls and 332 patients with ESRD. Our results suggested that rs1049255 polymorphism of CYBA modified the risk of ESRD (p  =  0.019; OR  =  0.625; 95%CI  =  0.424-0.921). GG genotype and G allele might be a protective factor against the risk of ESRD, especially in patients with chronic glomerulonephritis.