A neurodevelopmental survey of Angelman syndrome with genotype-phenotype correlations.
OBJECTIVE
Angelman syndrome (AS) is a neurodevelopmental disorder caused by a deletion on chromosome 15, uniparental disomy, imprinting defect, or UBE3A mutation. It is characterized by intellectual disability with minimal speech and certain behavioral characteristics. We used standardized measures to characterize the developmental profile and to analyze genotype-phenotype correlations in AS.


METHODS
The study population consisted of 92 children, between 5 months and 5 years of age, enrolled in a Natural History Study. Each participant was evaluated using the Bayley Scales of Infant and Toddler Development, Third Edition (BSID-III), the Vineland Adaptive Behavior Scales, Second Edition (VABS-II), and the Aberrant Behavior Checklist.


RESULTS
Seventy-four percent had a deletion and 26% had uniparental disomy, an imprinting defect or a UBE3A mutation ("non-deletion"). The mean +/- standard deviation BSID-III cognitive scale developmental quotient (DQ) was 40.5 +/- 15.5. Participants with deletions were more developmentally delayed than the non-deletion participants in all BSID-III domains except in expressive language skills. The cognitive DQ was higher than the DQ in each of the other domains, and the receptive language DQ was higher than the expressive language DQ. In the [ corrected] VABS-II, deletion participants had weaker motor and language skills than the non-deletion participants.


CONCLUSIONS
Children with AS have a distinct developmental and behavioral profile; their cognitive skills are stronger than their language and motor skills, and their receptive language skills are stronger than expressive language skills. Developmental outcomes are associated with genotype, with deletion patients having worse outcomes than non-deletion patients.
Gentile
Jennifer K
JK
NIH Rare Diseases Clinical Research Network-Angelman, Rett, & Prader-Willi Syndromes Consortium, Boston, MA, USA.
Tan
Wen-Hann
WH
Horowitz
Lucia T
LT
Bacino
Carlos A
CA
Skinner
Steven A
SA
Barbieri-Welge
Rene
R
Bauer-Carlin
Astrid
A
Beaudet
Arthur L
AL
Bichell
Terry Jo
TJ
Lee
Hye-Seung
HS
Sahoo
Trilochan
T
Waisbren
Susan E
SE
Bird
Lynne M
LM
Peters
Sarika U
SU
D017204:Angelman Syndrome / Q000235:genetics* / Q000523:psychology*; D002663:Child Language; D002675:Child, Preschool; D002884:Chromosomes, Human, Pair 15 / Q000235:genetics*; D003071:Cognition; D005260:Female; D017353:Gene Deletion; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D018392:Genomic Imprinting; D005838:Genotype; D006801:Humans; D007223:Infant; D008297:Male; D009048:Motor Skills; D010641:Phenotype; D044767:Ubiquitin-Protein Ligases / Q000235:genetics; D024182:Uniparental Disomy
C471639:UBE3A protein, human; D044767:Ubiquitin-Protein Ligases