Background: Autism spectrum disorder (ASD) has been identified as a risk marker for self-injurious behaviour. In this study we aimed to describe the prevalence, topography and correlates of self-injury in individuals with ASD in contrast to individuals with Fragile X and Down syndromes and examine person characteristics associated with self-injury…

Background: Self-injurious and aggressive behaviours are reported as components of some behavioural phenotypes but there are few studies comparing across syndrome groups. In this study we examined the prevalence of these behaviours and the associated person characteristics in seven genetic syndromes. Methods: Questionnaire data on self-injury and…

Background: Individuals with Prader-Willi syndrome (PWS) are at risk of sleep disturbances, such as excessive daytime sleepiness (EDS) and sleep apnoea, and behavioural problems. Sleep disturbances and their relationship with other variables had not been researched extensively in adults with PWS. Method: Sleep disturbances and behavioural problems…

Background: Children with 22q11.2 deletion syndrome (22q11DS) are at risk for social-behavioural and neurocognitive sequelae throughout development. The current study examined the impact of family environmental characteristics on social-behavioural and cognitive outcomes in this paediatric population. Method: Guardians of children with 22q11DS…

Background: Studies conducted on mild intellectual disability (MID) in children are infrequent and the prevalence rates vary widely. This study aimed to estimate the prevalence of MID in children in a French county (Isère), to describe the clinical signs and associated comorbidities, and to specify the aetiologies of this disability. Methods: The…

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…

Background: Studies have linked the behaviour problems of children with fragile X syndrome (FXS) to maternal well-being, but less is known about how behaviour problems relate to important family factors such as marital satisfaction and family cohesion. Methods: Married mothers of 115 adolescents and adults with FXS completed questionnaires and…

Background: The prevalence, phenomenology aetiology and correlates of four forms of challenging behaviour in 32 children and adults with Smith-Magenis syndrome (SMS) were investigated. Methods: Cognitive assessments, questionnaires and semi-structured interviews were used to gather data on intellectual disability, verbal and physical aggression,…

Background: Sleep disorders are common in individuals with neurodevelopmental disorders and may adversely affect daytime functioning. Children with Williams syndrome have been reported to have disturbed sleep; however, no studies have been performed to determine if these problems continue into adolescence and adulthood. Methods: This study…

Background: The increased interest in social interaction in Williams-Beuren syndrome (WBS) is evident from infancy onwards, together not only with increased empathy, positive interpersonal bias, but also with social disinhibition. Previous studies have described behavioural and emotional problems as being widely represented in WBS. There is…

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: Sleep problems are common in individuals with intellectual disability. Little is known about sleep in children and adults with Cri du Chat syndrome (CDC). Method: Sleep was investigated in 30 individuals with CDC using a sleep questionnaire. Sleep problems and sleep behaviours in individuals with CDC were compared with individuals with…

Background: Current research suggests that depression and anxiety may be common problems in women with the fragile X (FMR1) premutation. Methods: To learn more about this in a clinical setting, we asked 33 women with the FMR1 premutation and 20 women without the FMR1 premutation to complete the Brief Carroll Depression Scale (Brief CDS) and the…

Background: Marshall-Smith syndrome (MSS) is an infrequently described entity characterised by failure to thrive, developmental delay, abnormal bone maturation and a characteristic face. In studying the physical features of a group of patients, we noticed unusual behavioural traits. This urged us to study cognition, behavioural phenotype and…

Background: Males with fragile X syndrome and autism (FXS/autism) represent a distinct subgroup of males with FXS at risk for markedly poorer outcomes. Early identification and intervention can improve outcomes for males with autism spectrum disorder. Method: To advance the development of a specialised autism screening tool for young males with…