title: Common variants in CNDP1 and CNDP2, and risk of nephropathy in type 2 diabetes.
abstract: OBJECTIVE
  Several genome-wide linkage studies have shown an association between diabetic nephropathy and a locus on chromosome 18q harbouring two carnosinase genes, CNDP1 and CNDP2. Carnosinase degrades carnosine (β-alanyl-L-histidine), which has been ascribed a renal protective effect as a scavenger of reactive oxygen species. We investigated the putative associations of genetic variants in CNDP1 and CNDP2 with diabetic nephropathy (defined either as micro- or macroalbuminuria) and estimated GFR in type 2 diabetic patients from Sweden.
  
  
  METHODS
  We genotyped nine single nucleotide polymorphisms (SNPs) and one trinucleotide repeat polymorphism (D18S880, five to seven leucine repeats) in CNDP1 and CNDP2 in a case-control set-up including 4,888 unrelated type 2 diabetic patients (with and without nephropathy) from Sweden (Scania Diabetes Registry).
  
  
  RESULTS
  Two SNPs, rs2346061 in CNDP1 and rs7577 in CNDP2, were associated with an increased risk of diabetic nephropathy (rs2346061 p = 5.07 × 10(-4); rs7577 p = 0.021). The latter was also associated with estimated GFR (β = -0.037, p = 0.014), particularly in women. A haplotype including these SNPs (C-C-G) was associated with a threefold increased risk of diabetic nephropathy (OR 2.98, 95% CI 2.43-3.67, p < 0.0001).
  
  
  CONCLUSIONS
  These data suggest that common variants in CNDP1 and CNDP2 play a role in susceptibility to kidney disease in patients with type 2 diabetes.
authors.affiliation: Department of Clinical Sciences-Diabetes and Endocrinology, Lund University Diabetes Centre, Clinical Research Centre, University Hospital Skane, UMAS, 20502 Malmo, Sweden. Tarun.Ahluwalia@med.lu.se
authors.forename: T S
authors.initials: TS
authors.lastname: Ahluwalia
authors.forename: E
authors.initials: E
authors.lastname: Lindholm
authors.forename: L C
authors.initials: LC
authors.lastname: Groop
mesh_terms: D000328:Adult; D000368:Aged; D000419:Albuminuria / Q000503:physiopathology; D016022:Case-Control Studies; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000208:ethnology / Q000235:genetics*; D003928:Diabetic Nephropathies / Q000453:epidemiology* / Q000235:genetics* / Q000503:physiopathology; D004150:Dipeptidases / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics; D005838:Genotype; D005919:Glomerular Filtration Rate / Q000502:physiology; D006239:Haplotypes / Q000235:genetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D012307:Risk Factors; D013548:Sweden; D018911:Trinucleotide Repeats / Q000235:genetics
chemical_list: C522928:CNDP1 protein, human; D004150:Dipeptidases; C031499:CNDP2 protein, human