Related Experiment Videos
Familial aggregation of schizophrenia-like symptoms in Huntington's disease
D Tsuang1, L DiGiacomo, H Lipe
1Mental Health Service, VA Puget Sound Health Care System, Seattle, Washington 98108, USA.
Insights
Schizophrenia-like symptoms in Huntington's disease (HD) appear to be linked to the HD gene itself. This genetic link was observed in a juvenile-onset HD family, suggesting a potential inherited connection rather than coincidence.
Area of Science:
- Neurogenetics
- Psychiatric Genetics
- Neurodegenerative Diseases
Background:
- Huntington's disease (HD) is a progressive neurodegenerative disorder.
- An increased incidence of schizophrenia-like symptoms has been noted in HD patients.
- The underlying reasons for this association remain unexplained.
Observation:
- A unique juvenile-onset HD proband presented with schizophrenia-like symptoms, including delusions and hallucinations.
- A comparative case-control study utilized two families: one with a psychotic juvenile-onset HD proband and another with a nonpsychotic proband.
- Hypotheses explored included CAG repeat size, familial segregation, and coincidental gene presence.
Findings:
- Family history of schizophrenia-like symptoms segregated with the Huntington's disease gene.
- No association was found between psychotic symptoms and HD age of onset, CAG repeat size, or sex of the transmitting parent.
- The study suggests that schizophrenia-like symptoms may be genetically linked to the HD gene.
Implications:
- These findings suggest a potential genetic basis for schizophrenia-like symptoms in Huntington's disease.
- Further genetic and neurobiological research is warranted to elucidate the mechanism.
- Understanding this association could lead to improved diagnostic and therapeutic strategies for HD patients with psychiatric comorbidities.
Abstract:
An increased incidence of schizophrenia-like symptoms in Huntington's disease (HD) has been well-documented in the past. The reasons for this association, however, have never been explained. At the University of Washington Medical Genetics Clinic, we had the opportunity to evaluate a unique juvenile-onset HD proband who had schizophrenia-like symptoms. This patient was referred to our clinic because of new onset of somatic delusions and command auditory hallucinations early in the course of her illness. Since we had already evaluated other affected individuals in her family, we selected another family with a nonpsychotic juvenile-onset proband for comparison. Using these two families in a small case-control study, we investigated the following hypotheses which could explain the association between schizophrenia-like symptoms and HD: first, schizophrenia-like symptoms may be related to the number of CAG repeats in the HD gene; second, schizophrenia-like symptoms may segregate in certain HD families, for unknown reasons; and third, there may coincidentally be an unrelated gene for schizophrenia in certain HD families. Comparisons of clinical characteristics and the HD genotype showed that family history of schizophrenia-like symptoms segregated with the HD gene; however, age of onset of HD, size of CAG repeat, and sex of the transmitting parent were not associated with psychotic symptoms. Further genetic and neurobiological studies are necessary to investigate the potential mechanism underlying this association.