Objective: The authors' goal was to compare the thalamic, total brain, and intracranial volumes of patients with schizophrenia, their healthy siblings, and normal comparison subjects.
Method: Magnetic resonance imaging (MRI) brain scans were obtained for 32 same-sex siblings who were discordant for schizophrenia and 32 matched normal comparison subjects.
Results: Mean total thalamic volume, corrected for total brain volume, was significantly different among affected siblings, unaffected siblings, and comparison subjects. Thalamic volume was smallest in the patients; thalamic volume in their siblings was smaller than that of comparison subjects but larger than that of the patients with schizophrenia.
Conclusions: These results suggest that healthy siblings of patients with schizophrenia partially share the thalamic abnormalities of their affected relatives.