title: Intellectual asymmetry and genetic liability in first-degree relatives of probands with schizophrenia.
abstract: Intellectual asymmetry with superiority of verbal skills to spatial skills frequently characterises patients with schizophrenia, but it is unclear whether this pattern also reflects genetic susceptibility to the disorder. We examined the association of a continuous measure of genetic liability to schizophrenia with Verbal-Spatial Contrast IQ (an index of intellectual asymmetry) in 108 first-degree relatives without psychosis of probands with schizophrenia. Higher genetic liability was significantly associated with greater intellectual asymmetry in favour of verbal skills. Intellectual asymmetry with a relative superiority of verbal skills to spatial skills represents a putative endophenotype of schizophrenia.
authors.affiliation: Institute of Psychiatry, Department of Psychiatry, Division of Psychological Medicine, Box 63, De Crespigny Park, London SE5 8AF, UK. e.kravariti@iop.kcl.ac.uk
authors.forename: Eugenia
authors.initials: E
authors.lastname: Kravariti
authors.forename: Timothea
authors.initials: T
authors.lastname: Toulopoulou
authors.forename: Francesca
authors.initials: F
authors.lastname: Mapua-Filbey
authors.forename: Katja
authors.initials: K
authors.lastname: Schulze
authors.forename: Muriel
authors.initials: M
authors.lastname: Walshe
authors.forename: Pak
authors.initials: P
authors.lastname: Sham
authors.forename: Robin M
authors.initials: RM
authors.lastname: Murray
authors.forename: Colm
authors.initials: C
authors.lastname: McDonald
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005192:Family Health; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D007360:Intelligence; D007361:Intelligence Tests; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D012559:Schizophrenia / Q000235:genetics*; D012565:Schizophrenic Psychology; D014705:Verbal Behavior