title: The rs2231142 variant of the ABCG2 gene is associated with uric acid levels and gout among Japanese people.
abstract: OBJECTIVE
  Recent genome-wide association and functional studies have shown that the ABCG2 gene encodes for a urate transporter, and a common causal ABCG2 variant, rs2231142, leads to elevated uric acid levels and prevalent gout among Whites and Blacks. We examined whether this finding is observed in a Japanese population, since Asians have a high reported prevalence of the T-risk allele.
  
  
  METHODS
  A total of 3923 Japanese people from the Circulatory Risk in Communities Study aged 40-90 years were genotyped for rs2231142. Associations of the rs2231142 variant with serum uric acid levels and prevalence of gout and hyperuricaemia were examined.
  
  
  RESULTS
  The frequency of the T-risk allele was 31% in this Japanese sample. Multivariable adjusted mean uric acid levels were 7-9 micromol/l higher for TG and TT than GG carriers (P-additive = 0.0006). The multivariable-adjusted odds ratio (OR) of prevalent gout was 1.37 (95% CI 0.68, 2.76) for TG and 4.37 (95% CI 1.98, 9.62) for TT compared with the GG carriers (P-additive = 0.001). When evaluating the combined outcome of hyperuricaemia and gout, the respective ORs were 1.40 (95% CI 1.04, 1.87) for TG and 1.88 (95% CI 1.23, 2.89) for TT carriers. The population attributable risk was 29% for gout and 19% for gout and/or hyperuricaemia.
  
  
  CONCLUSIONS
  The association of the causal ABCG2 rs2231142 variant with uric acid levels and gout was confirmed in a sample of Japanese ancestry. Our study emphasizes the importance of this common causal variant in a population with a high risk allele frequency, especially as more Japanese adopt a Western lifestyle with a concomitant increase in mean serum uric acid levels.
authors.affiliation: Department of Public Health Medicine, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Japan.
authors.forename: Kazumasa
authors.initials: K
authors.lastname: Yamagishi
authors.forename: Takeshi
authors.initials: T
authors.lastname: Tanigawa
authors.forename: Akihiko
authors.initials: A
authors.lastname: Kitamura
authors.forename: Anna
authors.initials: A
authors.lastname: Köttgen
authors.forename: Aaron R
authors.initials: AR
authors.lastname: Folsom
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Iso
mesh_terms: D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People / Q000235:genetics; D005260:Female; D020022:Genetic Predisposition to Disease; D006073:Gout / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D033461:Hyperuricemia / Q000235:genetics* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism; D027361:Organic Anion Transporters / Q000235:genetics / Q000378:metabolism; D020641:Polymorphism, Single Nucleotide; D014527:Uric Acid / Q000097:blood*
chemical_list: C116614:ABCG2 protein, human; D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters; D009363:Neoplasm Proteins; D027361:Organic Anion Transporters; C103862:urate transporter; D014527:Uric Acid