title: Diabetic retinopathy is not associated with carbonic anhydrase gene polymorphisms.
abstract: OBJECTIVE
  Carbonic anhydrase is elevated in the vitreous of patients with proliferative diabetic retinopathy (PDR). This study aimed to determine if common polymorphisms in the carbonic anhydrase (CA) gene influence susceptibility to diabetic retinopathy (DR).
  
  
  METHODS
  In this multicentered study, a total of 235 control subjects with no DR, 158 subjects with nonproliferative DR (NPDR), 132 with proliferative DR (PDR), and 93 with clinically significant macular edema (CSME) were recruited. Blinding DR was defined as severe NPDR, PDR or CSME. DR subjects were drawn from both type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM) populations. Ten tag single nucleotide polymorphisms were selected to cover the majority of genetic diversity across the CA gene.
  
  
  RESULTS
  After adjustments were made for sex, disease duration, and HbA(1)c, no associations were found between any CA polymorphisms or haplotypes with any type of retinopathy in T1DM or T2DM.
  
  
  CONCLUSIONS
  Sequence variation in CA is not associated with the risk of developing retinopathy in T1DM or T2DM and increases the likelihood that elevated vitreous CA may be a consequence rather than cause of DR. Further genetic studies are required to have a better understanding of the pathogenesis of this debilitating diabetic complication.
authors.affiliation: Department of Ophthalmology, Flinders Medical Centre and Flinders University, Adelaide, Australia.
authors.forename: S
authors.initials: S
authors.lastname: Abhary
authors.forename: K P
authors.initials: KP
authors.lastname: Burdon
authors.forename: A
authors.initials: A
authors.lastname: Gupta
authors.forename: N
authors.initials: N
authors.lastname: Petrovsky
authors.forename: J E
authors.initials: JE
authors.lastname: Craig
mesh_terms: D000328:Adult; D000368:Aged; D002256:Carbonic Anhydrases / Q000235:genetics*; D016009:Chi-Square Distribution; D003930:Diabetic Retinopathy / Q000175:diagnosis / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D008040:Genetic Linkage; D006801:Humans; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide
chemical_list: D002256:Carbonic Anhydrases