Cytogenetic abnormalities in attention-deficit/hyperactivity disorder.
OBJECTIVE
To systematically assess the prevalence of fragile X syndrome, velocardiofacial syndrome, and other cytogenetic abnormalities in a group of children with attention-defict/hyperactivity disorder (ADHD).


METHODS
Blood samples were obtained from 100 children (64 boys) with combined type ADHD and normal intelligence and analyzed for the presence of fragile X mutation expansions, the 22q11.2 microdeletion associated with velocardiofacial syndrome, and cytogenetic abnormalities that would be detected with high resolution chromosomal banding.


RESULTS
One girl with ADHD had a sex chromosome aneuploidy (47,XXX). One boy had a premutation-sized allele for fragile X; no subjects showed the full mutation. Testing for 22q11.2 microdeletion was negative for all subjects with ADHD screened. None of these differences exceeded those expected by chance.


CONCLUSIONS
In the absence of clinical signs or positive family history, these relatively expensive laboratory assessments are not clinically indicated for children with ADHD and normal intelligence, and are not recommended as a component of other genetic investigations of this disorder.
Child Psychiatry Branch of the NIMH, USA.
Theresa M
TM
Bastain
Caroline M
CM
Lewczyk
Wendy S
WS
Sharp
Regina S
RS
James
Robert T
RT
Long
Patricia B
PB
Eagen
Christen L
CL
Ebens
Jeanne M
JM
Meck
Wai-Yee
WY
Chan
Ellen
E
Sidransky
Judith L
JL
Rapoport
F Xavier
FX
Castellanos
D000015:Abnormalities, Multiple; D001289:Attention Deficit Disorder with Hyperactivity / Q000453:epidemiology / Q000235:genetics*; D002648:Child; D002892:Chromosomes, Human, Pair 22 / Q000235:genetics; D003582:Cytogenetics / Q000379:methods*; D005145:Face / Q000002:abnormalities; D005260:Female; D005600:Fragile X Syndrome / Q000453:epidemiology / Q000235:genetics*; D006330:Heart Defects, Congenital / Q000453:epidemiology; D006801:Humans; D008297:Male; D010160:Palate, Soft / Q000002:abnormalities; D013577:Syndrome