title: Hyperuricaemia: contributions of urate transporter ABCG2 and the fractional renal clearance of urate.
abstract: To investigate the contributions towards hyperuricaemia of known risk factors, focusing on fractional (renal) clearance of urate (FCU) and variation in the ATP-binding cassette transporter, sub-family G 2 (ABCG2) gene.
  
  
  
  The contributions of age, sex, ancestry, Q141K genotype for ABCG2, FCU, sugar-sweetened beverage and alcohol consumption, metabolic syndrome disorders and measures of renal function to the risk of hyperuricaemia were evaluated by comparing hyperuricaemic (serum urate≥0.42 mmol/L, n=448) with normouricaemic (serum urate<0.42 mmol/L, n=344) participants using stepwise logistic regression. Model performance was evaluated using the area under the receiver operator characteristic curve (AUROC).
  
  
  
  ABCG2 genotype, FCU, male sex, body mass index, serum triglyceride concentrations, estimated glomerular filtration rate and consumption of alcohol were the best predictors of hyperuricaemia (AUROC 0.90, 81% accuracy). Homozygosity in the 141K variant for ABCG2 conferred an adjusted OR of 10.5 for hyperuricaemia (95% CI 2.4 to 46.2). For each 1% decrease of FCU, the adjusted OR increased by 51% (OR 1.51, 95% CI 1.37 to 1.66). There was no association between ABCG2 genotype and FCU (r=0.02, p=0.83).
  
  
  
  The ABCG2 141K variant and the FCU contribute strongly but independently to hyperuricaemia. These findings provide further evidence for a significant contribution of ABCG2 to extra-renal (gut) clearance of urate.
authors.affiliation: School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia Department of Clinical Pharmacology & Toxicology, St Vincent's Hospital, Sydney, New South Wales, Australia.
authors.forename: Diluk R W
authors.initials: DR
authors.lastname: Kannangara
authors.affiliation: Department of Biochemistry, University of Otago, Dunedin, New Zealand.
authors.forename: Amanda J
authors.initials: AJ
authors.lastname: Phipps-Green
authors.affiliation: Department of Medicine, University of Auckland, Auckland, New Zealand.
authors.forename: Nicola
authors.initials: N
authors.lastname: Dalbeth
authors.affiliation: Department of Medicine, University of Otago, Christchurch, Canterbury, New Zealand.
authors.forename: Lisa K
authors.initials: LK
authors.lastname: Stamp
authors.affiliation: School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia Department of Clinical Pharmacology & Toxicology, St Vincent's Hospital, Sydney, New South Wales, Australia.
authors.forename: Kenneth M
authors.initials: KM
authors.lastname: Williams
authors.affiliation: School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia Department of Clinical Pharmacology & Toxicology, St Vincent's Hospital, Sydney, New South Wales, Australia.
authors.forename: Garry G
authors.initials: GG
authors.lastname: Graham
authors.affiliation: School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia Department of Clinical Pharmacology & Toxicology, St Vincent's Hospital, Sydney, New South Wales, Australia St Vincent's Clinical School, University of New South Wales, Sydney, New South Wales, Australia.
authors.forename: Richard O
authors.initials: RO
authors.lastname: Day
authors.affiliation: Department of Biochemistry, University of Otago, Dunedin, New Zealand.
authors.forename: Tony R
authors.initials: TR
authors.lastname: Merriman
mesh_terms: D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2 / Q000097:blood*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D005260:Female; D014644:Genetic Variation; D006801:Humans; D033461:Hyperuricemia / Q000235:genetics* / Q000378:metabolism*; D007668:Kidney / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000097:blood*; D065667:Renal Elimination; D012307:Risk Factors; D014527:Uric Acid / Q000378:metabolism*
chemical_list: C116614:ABCG2 protein, human; D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D009363:Neoplasm Proteins; D014527:Uric Acid
keywords: Disease Activity; Gout; Pharmacogenetics