title: Evidence of association of KIBRA genotype with episodic memory in families of psychotic patients and controls.
abstract: The first genome-wide association study of human memory identified an association between a common T/C polymorphism of the KIBRA gene (rs17070145) and episodic memory performance in normal individuals; subsequent studies have implicated the same polymorphism in Alzheimer's disease. Since impaired neurocognitive performance, including memory, may be both a core feature of schizophrenia and a candidate endophenotype, we attempted to replicate this association in a total sample of 544 subjects (including patients with psychosis, their unaffected relatives as well as normal individuals). In the combined sample there was a significant association between the KIBRA T allele and better performance in the single principle component of the memory measures, which included immediate and delayed logical and visual memory from the Wechsler Memory Scale (p=0.019). In the unaffected individuals (patients' relatives and healthy controls) we observed an association of KIBRA with immediate and delayed logical memory (p=0.020 and 0.025, respectively), while in patients with psychosis with delayed visual memory (p=0.05). This study replicates the association between the KIBRA gene and episodic memory and suggests a possibly differential effect of the polymorphism in psychotic and non-psychotic individuals.
authors.affiliation: King's College London, Institute of Psychiatry, Department of Psychological Medicine and Psychiatry and NIHR Biomedical Research Centre, London, UK. evangelos.vassos@kcl.ac.uk
authors.forename: Evangelos
authors.initials: E
authors.lastname: Vassos
authors.forename: Elvira
authors.initials: E
authors.lastname: Bramon
authors.forename: Marco
authors.initials: M
authors.lastname: Picchioni
authors.forename: Muriel
authors.initials: M
authors.lastname: Walshe
authors.forename: Francesca M
authors.initials: FM
authors.lastname: Filbey
authors.forename: Eugenia
authors.initials: E
authors.lastname: Kravariti
authors.forename: Colm
authors.initials: C
authors.lastname: McDonald
authors.forename: Robin M
authors.initials: RM
authors.lastname: Murray
authors.forename: David A
authors.initials: DA
authors.lastname: Collier
authors.forename: Timothea
authors.initials: T
authors.lastname: Toulopoulou
mesh_terms: D000328:Adult; D005192:Family Health; D005260:Female; D055106:Genome-Wide Association Study; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D008297:Male; D008569:Memory Disorders / Q000209:etiology* / Q000235:genetics*; D008875:Middle Aged; D009483:Neuropsychological Tests; D010750:Phosphoproteins; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D011506:Proteins / Q000235:genetics*; D011618:Psychotic Disorders / Q000150:complications* / Q000235:genetics
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; D010750:Phosphoproteins; D011506:Proteins; C513637:WWC1 protein, human