title: A Genome-Wide Association Study Provides New Evidence That CACNA1C Gene is Associated With Diabetic Cataract.
abstract: OBJECTIVE
  Diabetic cataract is one of the major eye complications of diabetes. It was reported that cataract occurs two to five times more frequently in patients with diabetes compared with those with no diabetes. The purpose of this study was to identify genetic contributors of diabetic cataract based on a genome-wide association approach using a well-defined Scottish diabetic cohort.
  
  
  METHODS
  We adapted linked e-health records to define diabetic cataract. A diabetic cataract case in this study was defined as a type 2 diabetic patient who has ever been recorded in the linked e-health records to have cataracts in both eyes or who had previous cataract extraction surgeries in at least one eye. A control in this study was defined as a type 2 diabetic individual who has never been diagnosed as cataract in the linked e-health records and had no history of cataract surgeries. A standard genome-wide association approach was applied.
  
  
  RESULTS
  Overall, we have 2341 diabetic cataract cases and 2878 controls in the genetics of diabetes audit and research in Tayside Scotland (GoDARTS) dataset. We found that the P value of rs2283290 in the CACNA1C gene was 8.81 × 10(-10), which has reached genome-wide significance. We also identified that the blood calcium level was statistically different between diabetic cataract cases and controls.
  
  
  CONCLUSIONS
  We identified supporting evidence that CACNA1C gene is associated with diabetic cataract. The role of calcium in the cataractogenesis needs to be reevaluated in future studies.
authors.affiliation: Division of Population Health Sciences Ninewells Hospital and School of Medicine, University of Dundee, Dundee, United Kingdom.
authors.forename: Cheng
authors.initials: C
authors.lastname: Chang
authors.affiliation: Division of Population Health Sciences Ninewells Hospital and School of Medicine, University of Dundee, Dundee, United Kingdom.
authors.forename: Kaida
authors.initials: K
authors.lastname: Zhang
authors.affiliation: Division of Population Health Sciences Ninewells Hospital and School of Medicine, University of Dundee, Dundee, United Kingdom.
authors.forename: Abirami
authors.initials: A
authors.lastname: Veluchamy
authors.affiliation: Division of Population Health Sciences Ninewells Hospital and School of Medicine, University of Dundee, Dundee, United Kingdom.
authors.forename: Harry L
authors.initials: HL
authors.lastname: Hébert
authors.affiliation: Division of Population Health Sciences Ninewells Hospital and School of Medicine, University of Dundee, Dundee, United Kingdom.
authors.forename: Helen C
authors.initials: HC
authors.lastname: Looker
authors.affiliation: Division of Population Health Sciences Ninewells Hospital and School of Medicine, University of Dundee, Dundee, United Kingdom.
authors.forename: Helen M
authors.initials: HM
authors.lastname: Colhoun
authors.affiliation: Centre for Pharmacogenetics and Pharmacogenomics, Ninewells Hospital and School of Medicine, University of Dundee, Dundee, United Kingdom.
authors.forename: Colin N A
authors.initials: CN
authors.lastname: Palmer
authors.affiliation: Division of Population Health Sciences Ninewells Hospital and School of Medicine, University of Dundee, Dundee, United Kingdom.
authors.forename: Weihua
authors.initials: W
authors.lastname: Meng
mesh_terms: D000368:Aged; D020746:Calcium Channels, L-Type / Q000235:genetics* / Q000502:physiology; D002386:Cataract / Q000209:etiology / Q000235:genetics*; D048909:Diabetes Complications / Q000235:genetics*; D005260:Female; D055106:Genome-Wide Association Study; D006801:Humans; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis; D020641:Polymorphism, Single Nucleotide / Q000235:genetics
chemical_list: C079146:CACNA1C protein, human; D020746:Calcium Channels, L-Type