Gauthier et al. (2010) identified a family in which a proband and 2 affected brothers had schizophrenia. The proband was of European ancestry and had a diagnosis of schizoaffective disorder at age 19. He suffered from borderline mental ... Gauthier et al. (2010) identified a family in which a proband and 2 affected brothers had schizophrenia. The proband was of European ancestry and had a diagnosis of schizoaffective disorder at age 19. He suffered from borderline mental retardation, with an IQ of 73, and had no autistic features. His brother was diagnosed with schizophrenia at age 21 and had a history of hyperactivity in childhood and 1 seizure at age 10. He was described as having mild mental retardation, but no definitive IQ was available. The third brother was diagnosed with schizophrenia and atypical chronic psychosis at age 16. He had moderate mental retardation, with an IQ of 36. The 3 brothers had no evidence of dysmorphic features, and no psychiatric illness was known to be present in the extended family except for major depression in the mother. An individual from a second family, a 23-year-old woman of European ancestry, was diagnosed with schizoaffective disorder at age 11 years. She had normal growth and no evidence of dysmorphic features but had speech impairment and poor academic and social performance with an IQ of 73. She had no evidence of autism on formal testing.
In 3 brothers with schizophrenia, Gauthier et al. (2010) identified an R1117X mutation in the SHANK3 gene (606230.0002). The parents were unaffected and did not carry the mutation, which appeared to be inherited from the paternal strand through ... In 3 brothers with schizophrenia, Gauthier et al. (2010) identified an R1117X mutation in the SHANK3 gene (606230.0002). The parents were unaffected and did not carry the mutation, which appeared to be inherited from the paternal strand through germline mosaicism. In the individual from the second family, a de novo R536W mutation was found (606230.0003).