Sex-specific Associations of Variants in the Regulatory Regions of NADPH Oxidase-2 (CYBB) and Gluthatione Peroxidase 4 (GPX4) Genes With Kidney Disease in Type 1 Diabetes.

In the present study, three cohorts of type 1 diabetic patients (one Brazilian and two French/Belgium cohorts) were studied for the association with diabetic nephropathy (DN) with a total of 1396 patients. The patients were classified according to the urinary albumin-to-creatinine ratio (ACR) or urinary albumin excretion rate (UAER) in absence of nephropathy, defined as ACR <30 mg/g or UAER < 20 µg/min or < 20 mg/L and plasma creatinine <1.7 mg/dL; incipient nephropathy, defined as persistent microalbuminuria (ACR 30 - 300 mg/g of creatinine or UAER 20 - 200 µg/min or 20 - 200 mg/L) and plasma creatinine <1.7 mg/dL; established diabetic nephropathy, defined as past or present macroalbuminuria (ACR >300 mg/g of creatinine or UAER >200 µg/min or > 200 mg/L) and plasma creatinine <1.7 mg/dL; advanced diabetic nephropathy, defined as past or present macroalbuminuria, plasma creatinine >1.7 mg/dL and any renal replacement therapy. Genotyping of polymorphisms was performed by Real Time PCR using fluorescent-labelled probes.