title: The KCNH2 gene is associated with neurocognition and the risk of schizophrenia.
abstract: OBJECTIVE
  A genetic variant (rs3800779; M30) in the KCNH2 gene has been associated with schizophrenia, a lower intelligence quotient (IQ) and processing speed scores, altered brain functions and increased KCNH2-3.1. mRNA levels in the hippocampus. The aims of this study were to investigate whether the KCNH2 polymorphism is associated with schizophrenia-related neurocognitive deficits and to confirm the association between the variant and schizophrenia.
  
  
  METHODS
  The effects of the risk genotype on IQ and seven neurocognitive batteries were examined by the analysis of covariance in 191 healthy subjects. We performed a meta-analysis of the association between M30 and schizophrenia using five independent ethnic groups (1,720 cases; 2,418 controls).
  
  
  RESULTS
  Consistent with the previous study, we provided evidence that subjects with the risk T carriers had significantly lower IQ scores than those with the G/G genotype (P = 0.048). Of the seven neurocognitive batteries, subjects with the risk genotype demonstrated lower performances on attention/vigilance (P = 0.0079) and working memory (P = 0.0066) relative to subjects with the G/G genotype. Meta-analysis demonstrated evidence for an association between M30 and schizophrenia without showing heterogeneity across studies (odds ratio = 1.18; P = 0.0017).
  
  
  CONCLUSIONS
  These data suggest that the KCNH2 polymorphism could be associated with schizophrenia-related neuropsychological deficits and the risk of developing schizophrenia.
authors.affiliation: Molecular Research Center for Children's Mental Development, United Graduate School of Child Development, Osaka University, Kanazawa University and Hamamatsu University School of Medicine, Osaka, Japan. hashimor@psy.med.osaka-u.ac.jp
authors.forename: Ryota
authors.initials: R
authors.lastname: Hashimoto
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Ohi
authors.forename: Yuka
authors.initials: Y
authors.lastname: Yasuda
authors.forename: Motoyuki
authors.initials: M
authors.lastname: Fukumoto
authors.forename: Hidenaga
authors.initials: H
authors.lastname: Yamamori
authors.forename: Kouzin
authors.initials: K
authors.lastname: Kamino
authors.forename: Takashi
authors.initials: T
authors.lastname: Morihara
authors.forename: Masao
authors.initials: M
authors.lastname: Iwase
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kazui
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Takeda
mesh_terms: D000328:Adult; D001288:Attention; D000072237:ERG1 Potassium Channel; D051638:Ether-A-Go-Go Potassium Channels / Q000235:genetics*; D005006:Ethnicity / Q000235:genetics; D005260:Female; D020022:Genetic Predisposition to Disease; D014644:Genetic Variation; D006801:Humans; D008607:Intellectual Disability / Q000209:etiology / Q000235:genetics*; D007361:Intelligence Tests; D007564:Japan / Q000453:epidemiology; D008297:Male; D008570:Memory, Short-Term; D008875:Middle Aged; D009483:Neuropsychological Tests; D020641:Polymorphism, Single Nucleotide; D012559:Schizophrenia / Q000150:complications / Q000453:epidemiology / Q000235:genetics*; D012565:Schizophrenic Psychology
chemical_list: D000072237:ERG1 Potassium Channel; D051638:Ether-A-Go-Go Potassium Channels; C000606913:KCNH2 protein, human