title: Effects of vitamin D receptor gene polymorphism and clinical characteristics on risk of diabetic retinopathy in Han Chinese type 2 diabetes patients.
abstract: OBJECTIVE
  The purpose of this study was to investigate the association of VDR polymorphism with development of retinopathy in a Han Chinese population with type 2 diabetes mellitus.
  
  
  METHODS
  A total of 204 T2DM patients were subdivided into groups without diabetic retinopathy (NDR, n=110) and those with DR (n=94). VDR rs2228570 (FokI:C>T), rs1544410 (BsmI:G>A), and rs7975232 (Apal:A>C) polymorphism was assayed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).
  
  
  RESULTS
  Diabetes duration (10.0 vs. 5.0 years, P<0.01) was longer, systolic blood pressure (143.98 ± 24.31 vs. 135.11 ± 15.23, P<0.01), and HbA1c (9.2 ± 2.06 vs. 8.35 ± 1.62, P<0.01) were higher in DR than in NDR patients. Distribution frequencies of the rs2228570, rs1544410, and rs7975232 genotypes followed the Hardy-Weinberg equilibrium. VDR rs2228570 TT genotype frequency was significantly higher in DR (n=30; 31.9%) than in NDR patients (n=14; 12.7%; P<0.01). DR patients carried more rs2228570 T alleles (n=113; 60.1%) than did NDR patients (n=89; 40.5%; P<0.01). Genotype frequencies of rs1544410 and rs7975232 in NDR and DR patients were not different. Logistic analysis confirmed that diabetes duration (odds ratio (OR) 1.108, P<0.01), SBP (OR 1.022, P<0.05), HbA1c (OR 1.267, P<0.05), and the VDR rs2228570 T allele (OR 1.467, P<0.01) were independently associated with DR risk. TAA haplotype frequency was significantly higher in DR (24.0%) than in NDR (16.1%) patients (P<0.05).
  
  
  CONCLUSIONS
  Diabetes duration, SBP, HbA1c, and the rs2228570 T allele were associated with increased risk of DR. VDR rs2228570 might be good candidate biomarker of DR in Han Chinese T2DM patients.
authors.affiliation: Department of Endocrinology, The Second Affiliated Hospital of Anhui Medical University, Hefei 230061, PR China.
authors.forename: Xing
authors.initials: X
authors.lastname: Zhong
authors.affiliation: Department of Endocrinology, The Second Affiliated Hospital of Anhui Medical University, Hefei 230061, PR China.
authors.forename: Yijun
authors.initials: Y
authors.lastname: Du
authors.affiliation: Department of Endocrinology, The Fourth Affiliated Hospital of Anhui Medical University, Hefei 230022, PR China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Lei
authors.affiliation: Department of Endocrinology, The Second Affiliated Hospital of Anhui Medical University, Hefei 230061, PR China.
authors.forename: Nina
authors.initials: N
authors.lastname: Liu
authors.affiliation: Department of Endocrinology, The Second Affiliated Hospital of Anhui Medical University, Hefei 230061, PR China.
authors.forename: Yanyun
authors.initials: Y
authors.lastname: Guo
authors.affiliation: Department of Endocrinology, The Second Affiliated Hospital of Anhui Medical University, Hefei 230061, PR China. Electronic address: pantianrong1968@163.com.
authors.forename: Tianrong
authors.initials: T
authors.lastname: Pan
mesh_terms: D002681:China; D017931:DNA Primers; D003924:Diabetes Mellitus, Type 2 / Q000150:complications*; D003930:Diabetic Retinopathy / Q000150:complications / Q000208:ethnology / Q000235:genetics*; D005006:Ethnicity; D006801:Humans; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D018167:Receptors, Calcitriol / Q000235:genetics*
chemical_list: D017931:DNA Primers; D018167:Receptors, Calcitriol
keywords: Diabetic retinopathy; Polymorphism; Risk factors; Vitamin D receptor