title: Genome-wide association study of schizophrenia in a Japanese population.
abstract: BACKGROUND
  Genome-wide association studies have detected a small number of weak but strongly supported schizophrenia risk alleles. Moreover, a substantial polygenic component to the disorder consisting of a large number of such alleles has been reported by the International Schizophrenia Consortium.
  
  
  METHODS
  We report a Japanese genome-wide association study of schizophrenia comprising 575 cases and 564 controls. We attempted to replicate 97 markers, representing a nonredundant panel of markers derived mainly from the top 150 findings, in up to three data sets totaling 1990 cases and 5389 controls. We then attempted to replicate the observation of a polygenic component to the disorder in the Japanese and to determine whether this overlaps that seen in UK populations.
  
  
  RESULTS
  Single-locus analysis did not reveal genome-wide support for any locus in the genome-wide association study sample (best p = 6.2 × 10(-6)) or in the complete data set in which the best supported locus was SULT6B1 (rs11895771: p = 3.7 × 10(-5) in the meta-analysis). Of loci previously supported by genome-wide association studies, we obtained in the Japanese support for NOTCH4 (rs2071287: p(meta) = 5.1 × 10(-5)). Using the approach reported by the International Schizophrenia Consortium, we replicated the observation of a polygenic component to schizophrenia within the Japanese population (p = .005). Our trans Japan-UK analysis of schizophrenia also revealed a significant correlation (best p = 7.0 × 10(-5)) in the polygenic component across populations.
  
  
  CONCLUSIONS
  These results indicate a shared polygenic risk of schizophrenia between Japanese and Caucasian samples, although we did not detect unequivocal evidence for a novel susceptibility gene for schizophrenia.
authors.affiliation: Department of Psychiatry, School of Medicine, Fujita Health University, Toyoake, Aichi, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Ikeda
authors.forename: Branko
authors.initials: B
authors.lastname: Aleksic
authors.forename: Yoko
authors.initials: Y
authors.lastname: Kinoshita
authors.forename: Tomo
authors.initials: T
authors.lastname: Okochi
authors.forename: Kunihiro
authors.initials: K
authors.lastname: Kawashima
authors.forename: Itaru
authors.initials: I
authors.lastname: Kushima
authors.forename: Yoshihito
authors.initials: Y
authors.lastname: Ito
authors.forename: Yukako
authors.initials: Y
authors.lastname: Nakamura
authors.forename: Taro
authors.initials: T
authors.lastname: Kishi
authors.forename: Takenori
authors.initials: T
authors.lastname: Okumura
authors.forename: Yasuhisa
authors.initials: Y
authors.lastname: Fukuo
authors.forename: Hywel J
authors.initials: HJ
authors.lastname: Williams
authors.forename: Marian L
authors.initials: ML
authors.lastname: Hamshere
authors.forename: Dobril
authors.initials: D
authors.lastname: Ivanov
authors.forename: Toshiya
authors.initials: T
authors.lastname: Inada
authors.forename: Michio
authors.initials: M
authors.lastname: Suzuki
authors.forename: Ryota
authors.initials: R
authors.lastname: Hashimoto
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ujike
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Takeda
authors.forename: Nick
authors.initials: N
authors.lastname: Craddock
authors.forename: Kozo
authors.initials: K
authors.lastname: Kaibuchi
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Owen
authors.forename: Norio
authors.initials: N
authors.lastname: Ozaki
authors.forename: Michael C
authors.initials: MC
authors.lastname: O'Donovan
authors.forename: Nakao
authors.initials: N
authors.lastname: Iwata
mesh_terms: D000328:Adult; D000483:Alleles; D044466:Asian People; D005260:Female; D005500:Follow-Up Studies; D005787:Gene Frequency; D005819:Genetic Markers; D020022:Genetic Predisposition to Disease; D055106:Genome-Wide Association Study; D005838:Genotype; D006239:Haplotypes; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D020412:Multifactorial Inheritance; D020641:Polymorphism, Single Nucleotide; D011786:Quality Control; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012559:Schizophrenia / Q000453:epidemiology* / Q000235:genetics*; D006113:United Kingdom / Q000453:epidemiology
chemical_list: D005819:Genetic Markers