Background: We have previously exploited clinical features in an effort to reduce genetic heterogeneity in bipolar families. Here we assess the familiality of psychotic symptoms to determine whether this feature may increase homogeneity and inform the discussion of possible overlap in genetic susceptibility to bipolar disorder and schizophrenia. Methods: The prevalence of hallucinations or delusions during an affective episode, were compared in first-degree bipolar relatives (bipolar I, bipolar II or schizoaffective, manic) of bipolar I (BP I) probands with and without these psychotic symptoms. Results: Of 65 probands, 47 had psychotic symptoms and 18 did not. Among relatives of psychotic probands 45/106 (42%) were psychotic. Among relatives of non-psychotic probands, 6/35 (17%) were psychotic (p=.007). Of the 47 psychotic proband families, 30 contained at least one psychotic relative. In this subset of 30 families, 45/79 relatives (57%) had psychotic symptoms. The 30 families included six relatives with schizoaffective, manic disorder while the non-psychotic proband families contained no schizoaffective, manic relatives. Conclusion: Psychotic symptoms may differentiate a genetic subtype of bipolar disorder. Psychotic bipolar disorder families should be used to examine evidence for linkage on chromosomal regions such as 10p, 13q, 18p, and 22q where vulnerability genes for schizophrenia may reside.
|Original language||English (US)|
|Number of pages||1|
|Journal||American Journal of Medical Genetics - Neuropsychiatric Genetics|
|State||Published - Aug 7 2000|
ASJC Scopus subject areas
- Psychiatry and Mental health
- Cellular and Molecular Neuroscience