Clinical and neurobiological correlates of cytogenetic abnormalities in childhood-onset schizophrenia.
OBJECTIVE
Cytogenetic abnormalities are increased in schizophrenia, suggesting a possible etiologic contribution. However, their clinical and pathophysiologic roles in the disorder are unknown. To investigate this, a group of children and adolescents participating in a comprehensive study of childhood-onset schizophrenia were screened for chromosomal abnormalities, and their clinical and neurobiological correlates were examined.


METHODS
Cytogenetic screening with the use of high-resolution banding, fluorescent in situ hybridization for chromosome 22q11 deletions, and molecular fragile X testing was undertaken in a group of 47 children and adolescents with very early onset of schizophrenia. Clinical, neurobiological (including brain morphometry), and risk factor measures of the subjects with cytogenetic abnormalities were compared with those of the remaining patients without cytogenetic anomalies.


RESULTS
Five patients had previously undiagnosed cytogenetic abnormalities. Lower performance IQ and more pronounced premorbid developmental impairments were seen in this subgroup. Rates of obstetric complications, familial schizophrenia spectrum disorders, and familial eye tracking dysfunction were similar for the patients with and without cytogenetic abnormalities.


CONCLUSIONS
Cytogenetic abnormalities appear to be increased in childhood-onset schizophrenia, suggesting an association with a very early age at onset. The data from the subgroup of patients with cytogenetic anomalies are consistent with a model in which a childhood onset of schizophrenia is due to a greater impairment of neurodevelopment secondary to the interaction of a number of factors, particularly genetic ones.
Nicolson
R
R
Child Psychiatry Branch, Yale University, New Haven, Conn., USA. rn54q@nih.gov
Giedd
J N
JN
Lenane
M
M
Hamburger
S
S
Singaracharlu
S
S
Bedwell
J
J
Fernandez
T
T
Thaker
G K
GK
Malaspina
D
D
Rapoport
J L
JL
D000293:Adolescent; D017668:Age of Onset; D001921:Brain / Q000033:anatomy & histology; D010054:Brief Psychiatric Rating Scale / Q000706:statistics & numerical data; D002552:Cerebral Ventricles / Q000033:anatomy & histology; D002648:Child; D002869:Chromosome Aberrations; D002872:Chromosome Deletion; D002658:Developmental Disabilities / Q000175:diagnosis / Q000453:epidemiology; D005190:Family; D005260:Female; D006624:Hippocampus / Q000033:anatomy & histology; D006801:Humans; D007361:Intelligence Tests / Q000706:statistics & numerical data; D008279:Magnetic Resonance Imaging; D008297:Male; D015995:Prevalence; D011569:Psychiatric Status Rating Scales / Q000706:statistics & numerical data; D012307:Risk Factors; D012559:Schizophrenia / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics*; D012565:Schizophrenic Psychology