Phelan-McDermid syndrome (PMS), caused by "SHANK3" haploinsufficiency, lacks natural history data. We report the trajectory of adaptive behavior from a prospective, longitudinal, natural history study. English-speaking people aged 3-21 years with a PMS molecular diagnosis were followed over 2 years. We analyzed longitudinal Vineland…

Smith-Magenis syndrome (SMS) is a genetic syndrome most often caused by a deletion on chromosome 17 or more rarely by a mutation in the retinoic acid-induced 1 gene. The aim of this study was to investigate the Developmental Behavior Checklist (DBC) profile of persons with SMS and the associations between behavioural and emotional problems, age,…

Background: Individuals with fragile-X syndrome exhibit developmental delay, hyperexcitation and social anxiety; they also show lack of attention and hyperactivity. Few studies have investigated whether levels of functioning change with increasing age. Here, we explored developmental changes across adolescence in the cognitive and behavioural…

This study investigates cognitive abilities of pre/primary school children without and with spina bifida in Uganda. Qualitative semi structured interviews and quantitative functioning scales measurements were combined and conducted with 133 parents, 133 children with spina bifida, and 35 siblings. ANCOVA was used to test for differences in…

Background: While behavioural abnormalities are fundamental features of Rett syndrome (RTT), few studies have examined the RTT behavioural phenotype. Most of these reports have focused on autistic features, linked to the early regressive phase of the disorder, and few studies have applied standardised behavioural measures. We used a battery of…

Background: Little is known about trajectories of cognitive functioning as individuals with Williams syndrome (WS) move though adulthood. Method: The present study investigated cognitive, linguistic and adaptive functioning in adults with WS aged 19-55 years, using both cross-sectional and longitudinal approaches. Results: Data from the…

In order to investigate unique and shared characteristics and to determine factors predictive of group classification, quantitative comparisons of behavioral and emotional problems were assessed using the Developmental Behavior Checklist (DBC-P) and the Vineland Adaptive Behavior Scales in autistic disorder, Williams syndrome (WS), and…