title: Genetic underpinnings of left superior temporal gyrus thickness in patients with schizophrenia.
abstract: OBJECTIVE
  Schizophrenia is a highly disabling psychiatric disorder with a heterogeneous phenotypic appearance. We aimed to further the understanding of some of the underlying genetics of schizophrenia, using left superior temporal gyrus (STG) grey matter thickness reduction as an endophenoptype in a genome-wide association (GWA) study.
  
  
  METHODS
  Structural magnetic resonance imaging (MRI) and genetic data of the Mind Clinical Imaging Consortium (MCIC) study of schizophrenia were used to analyse the interaction effects between 1,067,955 single nucleotide polymorphisms (SNPs) and disease status on left STG thickness in 126 healthy controls and 113 patients with schizophrenia. We next used a pathway approach to detect underlying pathophysiological pathways that may be related to schizophrenia.
  
  
  RESULTS
  No SNP by diagnosis interaction effect reached genome-wide significance (5 × 10-8) in our GWA study, but 10 SNPs reached P-values less than 10-6. The most prominent pathways included those involved in insulin, calcium, PI3K-Akt and MAPK signalling.
  
  
  CONCLUSIONS
  Our strongest findings in the GWA study and pathway analysis point towards an involvement of glucose metabolism in left STG thickness reduction in patients with schizophrenia only. These results are in line with recently published studies, which showed an increased prevalence of psychosis among patients with metabolic syndrome-related illnesses including diabetes.
authors.affiliation: Translational Developmental Neuroscience Section, Department of Child and Adolescent Psychiatry, Faculty of Medicine Carl Gustav Carus of the Technische Universität Dresden , Dresden , Germany.
authors.forename: Rick P F
authors.initials: RP
authors.lastname: Wolthusen
authors.forename: Johanna
authors.initials: J
authors.lastname: Hass
authors.forename: Esther
authors.initials: E
authors.lastname: Walton
authors.forename: Jessica A
authors.initials: JA
authors.lastname: Turner
authors.forename: Veit
authors.initials: V
authors.lastname: Rössner
authors.forename: Scott R
authors.initials: SR
authors.lastname: Sponheim
authors.forename: Beng-Choon
authors.initials: BC
authors.lastname: Ho
authors.forename: Daphne J
authors.initials: DJ
authors.lastname: Holt
authors.forename: Randy L
authors.initials: RL
authors.lastname: Gollub
authors.forename: Vince
authors.initials: V
authors.lastname: Calhoun
authors.forename: Stefan
authors.initials: S
authors.lastname: Ehrlich
keywords: cortical thickness; genetics; imaging; schizophrenia; superior temporal gyrus