Brief report: association of sex chromosome anomalies with childhood-onset psychotic disorders.
OBJECTIVE
An apparent excess of sex chromosome aneuploidies (XXY, XXX, and possibly XYY) has been reported in patients with adult-onset schizophrenia and with unspecified psychoses. This study describes the results of cytogenetic screening carried out for pediatric patients meeting DMS-III-R criteria for childhood-onset schizophrenia (COS) and a subgroup of patients with childhood-onset psychotic disorder not otherwise specified, provisionally labeled by the authors as multidimensionally impaired (MDI).


METHODS
From August 1990 to July 1997, karyotypes were determined for 66 neuroleptic-nonresponsive pediatric patients (28 MDI, 38 COS), referred to the National Institute of Mental Health for an inpatient treatment trial of clozapine.


RESULTS
Four (6.1%) of 66 patients (3 MDI, 1 COS) were found to have sex chromosome anomalies (mosaic 47,XXY; 47,XXY; 47,XYY; mosaic 45,XO, respectively), which is higher than the expected rate of 1 per 426 children or 2.34 per 1,000 in the general population (4/66 versus 1/426, chi 2 = 19.2, df = 1, p = .00001). All cases had been previously undiagnosed.


CONCLUSIONS
These findings lend support to a hypothesis that a loss of balance of gene products on the sex chromosomes may predispose affected individuals to susceptibility to additional genetic and environmental insults that result in childhood-onset psychotic disorders. Karyotyping of children with psychotic disorders should be routine.
Kumra
S
S
Child Psychiatry Branch, NIMH, Bethesda, MD 20892, USA.
Wiggs
E
E
Krasnewich
D
D
Meck
J
J
Smith
A C
AC
Bedwell
J
J
Fernandez
T
T
Jacobsen
L K
LK
Lenane
M
M
Rapoport
J L
JL
D000293:Adolescent; D000782:Aneuploidy; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D009030:Mosaicism; D019965:Neurocognitive Disorders / Q000175:diagnosis / Q000235:genetics / Q000523:psychology; D011569:Psychiatric Status Rating Scales; D012307:Risk Factors; D012561:Schizophrenia, Childhood / Q000175:diagnosis / Q000235:genetics* / Q000523:psychology; D012729:Sex Chromosome Aberrations / Q000235:genetics* / Q000523:psychology; D014960:X Chromosome; D014997:XYY Karyotype / Q000235:genetics / Q000523:psychology; D014998:Y Chromosome