Peer-Reviewed Journal Details
Mandatory Fields
Hall, MH,Schulze, K,Sham, P,Kalidindi, S,McDonald, C,Bramon, E,Levy, DL,Murray, RM,Rijsdijk, F
2008
July
American Journal Of Medical Genetics Part B-Neuropsychiatric Genetics
Further evidence for shared genetic effects between psychotic bipolar disorder and p50 suppression: A combined twin and family study
Published
()
Optional Fields
P50 ERPs endophenotype bipolar disorder twin modelling AUDITORY-EVOKED-RESPONSES EVENT-RELATED POTENTIALS NEUROPHYSIOLOGICAL EVIDENCE SCHIZOPHRENIC-PATIENTS UNAFFECTED RELATIVES ENDOPHENOTYPE LINKAGE ABNORMALITIES NORMALIZATION HERITABILITY
147B
619
627
P50 suppression deficit has been reported in patients with psychotic bipolar disorder. In our previous report on twin pairs concordant and discordant for bipolar disorder, we found significant genetic overlap between bipolar disorder and P50 sensory gating. However, the sample size in that study was relatively small. A separate study, the Maudsley Bipolar Family Study, reported diminished P50 gating in unaffected relatives of psychotic bipolar patients. However, genetic and environmental influences are confounded in family studies due to lack of monozygotic (MZ) twin pairs. The current study combines the twin sample and the family sample in order to improve statistical power and study design, with the aims of. (1) substantiating the association between psychotic bipolar disorder and diminished P50 suppression and (2) verifying the genetic overlap between the two traits reported in the twin sample. We also assessed the relationship between bipolar disorder and an alternative suppression index, the P50 Condition-Testing (C-T) amplitude difference. A total of 309 subjects was included in this study, comprising 91 twin pairs, 31 bipolar families, and 45 unrelated healthy controls. Statistical analyses were based on structural equation modeling. Bipolar disorder was significantly associated with a diminished P50 suppression ratio and decreased C-T amplitude difference. Shared genetic factors were the main source of these associations. Suppression impairment was due to larger, poorly gated, T amplitude responses. The results provide further evidence that impaired P50 suppressions are promising endophenotypes for psychotic bipolar disorder. The non-specificity of impaired P50 suppression may reflect the impact of shared psychosis susceptibility genes. (C) 2008 Wiley-Liss, Inc.
DOI 10.1002/ajmg.b.30653
Grant Details
Publication Themes