Speech delay and autism spectrum behaviors are frequently associated with duplication of the 7q11.23 Williams-Beuren syndrome region.
OBJECTIVE
Williams-Beuren syndrome is among the most well-characterized microdeletion syndromes, caused by recurrent de novo microdeletions at 7q11.23 mediated by nonallelic homologous recombination between low copy repeats flanking this critical region. However, the clinical phenotype associated with reciprocal microduplication of this genomic region is less well described. We investigated the molecular, clinical, neurodevelopmental, and behavioral features of seven patients with dup(7)(q11.23), including two children who inherited the microduplication from one of their parents, to more fully characterize this emerging microduplication syndrome.


METHODS
Patients were identified by array-based comparative genomic hybridization. Clinical examinations were performed on seven affected probands, and detailed cognitive and behavioral evaluations were carried out on four of the affected probands.


RESULTS
Our findings confirm initial reports of speech delay seen in patients with dup(7)(q11.23) and further delineate and expand the phenotypic spectrum of this condition to include communication, social interactions, and repetitive interests that are often observed in individuals diagnosed with autism spectrum disorders.


CONCLUSIONS
Array-based comparative genomic hybridization is a powerful means of detecting genomic imbalances and identifying molecular etiologies in the clinic setting, including genomic disorders such as Williams-Beuren syndrome and dup(7)(q11.23). We propose that dup(7)(q11.23) syndrome may be as frequent as Williams-Beuren syndrome and a previously unrecognized cause of language delay and behavioral abnormalities. Indeed, these individuals may first be referred for evaluation of autism, even if they do not ultimately meet diagnostic criteria for an autism spectrum disorder.
Department of Molecular and Human Genetics, Baylor College of Medicine and Texas Children's Hospital, Houston, Texas 77030, USA.
Jonathan S
JS
Berg
Nicola
N
Brunetti-Pierri
Sarika U
SU
Peters
Sung-Hae L
SH
Kang
Chin-to
CT
Fong
Jessica
J
Salamone
Debra
D
Freedenberg
Vickie L
VL
Hannig
Lisa Albers
LA
Prock
David T
DT
Miller
Peter
P
Raffalli
David J
DJ
Harris
Robert P
RP
Erickson
Christopher
C
Cunniff
Gary D
GD
Clark
Maria A
MA
Blazo
Daniel A
DA
Peiffer
Kevin L
KL
Gunderson
Trilochan
T
Sahoo
Ankita
A
Patel
James R
JR
Lupski
Arthur L
AL
Beaudet
Sau Wai
SW
Cheung
D000328:Adult; D001321:Autistic Disorder / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology; D002648:Child; D002652:Child Behavior; D002675:Child, Preschool; D002869:Chromosome Aberrations; D002897:Chromosomes, Human, Pair 7 / Q000235:genetics*; D005260:Female; D006801:Humans; D007805:Language Development Disorders / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology; D008297:Male; D009693:Nucleic Acid Hybridization; D020411:Oligonucleotide Array Sequence Analysis; D040641:Quantitative Trait Loci; D012919:Social Behavior; D018980:Williams Syndrome / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology