title: Disturbed frontal gyrification within families affected with schizophrenia.
abstract: OBJECTIVE
  Recently, in a post-mortem and a subsequent structural MR study, a significantly increased gyrification index (GI) was demonstrated in the frontal lobe in individuals with schizophrenia. To examine whether frontal lobe hypergyria is region-specific and whether this might be a suitable endophenotype in the search for the genetic basis of schizophrenia, the frontal as well as parieto-occipital GI were determined in MRI scans of families affected with schizophrenia.
  
  
  METHODS
  In the MRI scans of 48 subjects suffering from schizophrenia, in 82 of their first-degree relatives and in 41 control subjects, the GI was determined in three sections anterior to the genu of the corpus callosum and three sections posterior to the splenium, thus allowing for a selective determination of this measure in the frontal as well as the parietal lobe. Outer and inner contours constituting the GI was determined in each section by manual tracing. Statistical analysis was performed using MANOVA with factors diagnostic group and intervening factors from preliminary analyses.
  
  
  RESULTS
  The frontal, but not parieto-occipital GI was significantly higher in schizophrenic patients as well as unaffected relatives compared with control subjects (right: 7%, F=13.24, df=3, 155, p<0.0005, left: 6%, F=8.92, df=3, 155, p<0.0005). There was no overall difference between affected and unaffected family members. On the left side however, there was a significant interaction between diagnostic group and genetic loading (F=4.68, df=2, 101, p=0.01): significantly higher GI was found in affected compared with unaffected family members only in uniaffected and not multiaffected families.
  
  
  CONCLUSIONS
  These results support our primary finding of hypergyria in the frontal lobe in schizophrenic patients. Compared to the parietal lobe, hypergyria seems to affect the frontal lobe selectively and serves as a suitable neurodevelopmental, possibly even an endophenotypic marker.
authors.affiliation: Department of Psychiatry and Psychotherapy, University of Göttingen, Von-Siebold-Str. 5, 37075 Göttingen, Germany. pfalkai@gwdg.de
authors.forename: Peter
authors.initials: P
authors.lastname: Falkai
authors.forename: William G
authors.initials: WG
authors.lastname: Honer
authors.forename: Thomas
authors.initials: T
authors.lastname: Kamer
authors.forename: Simone
authors.initials: S
authors.lastname: Dustert
authors.forename: Kai
authors.initials: K
authors.lastname: Vogeley
authors.forename: Thomas
authors.initials: T
authors.lastname: Schneider-Axmann
authors.forename: Indra
authors.initials: I
authors.lastname: Dani
authors.forename: Michael
authors.initials: M
authors.lastname: Wagner
authors.forename: Marcella
authors.initials: M
authors.lastname: Rietschel
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Müller
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Schulze
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Gaebel
authors.forename: Joachim
authors.initials: J
authors.lastname: Cordes
authors.forename: Helmut
authors.initials: H
authors.lastname: Schönell
authors.forename: Hans H
authors.initials: HH
authors.lastname: Schild
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Block
authors.forename: Frank
authors.initials: F
authors.lastname: Träber
authors.forename: Helmuth
authors.initials: H
authors.lastname: Steinmetz
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Maier
authors.forename: Ralf
authors.initials: R
authors.lastname: Tepest
mesh_terms: D000328:Adult; D000367:Age Factors; D003337:Corpus Callosum / Q000473:pathology; D004292:Dominance, Cerebral / Q000235:genetics / Q000502:physiology; D005260:Female; D005625:Frontal Lobe / Q000002:abnormalities* / Q000473:pathology; D040741:Genetic Load; D005819:Genetic Markers / Q000235:genetics; D020022:Genetic Predisposition to Disease / Q000235:genetics; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D009778:Occipital Lobe / Q000002:abnormalities / Q000473:pathology; D010296:Parietal Lobe / Q000002:abnormalities / Q000473:pathology; D010641:Phenotype; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000175:diagnosis / Q000235:genetics*; D012737:Sex Factors
chemical_list: D005819:Genetic Markers