A polymorphism in the gene encoding carnosinase (CNDP1) as a predictor of mortality and progression from nephropathy to end-stage renal disease in type 1 diabetes mellitus

Aims/hypothesis Homozygosity for a five leucine repeat (5L–5L) in the carnosinase gene (CNDP1) has been found to be cross-sectionally associated with a low frequency of diabetic nephropathy (DN), mainly in type 2 diabetes. We prospectively investigated in patients with type 1 diabetes whether: (1) 5L–5L is associated with mortality; (2) there is an interaction of 5L–5L with DN or sex for prediction of mortality; and (3) 5L–5L is associated with progression to end-stage renal disease (ESRD). Methods In this prospective study in white European patients with type 1 diabetes, individuals with DN were defined by persistent albuminuria ≥300 mg/24 h. Controls without nephropathy were defined by persistent (>15 years) normoalbuminuria