Preference for water-related items in Angelman syndrome, Down syndrome and non-specific intellectual disability

Repetitive and Self-injurious Behaviors in Children with Cornelia de Lange Syndrome

Cornelia de Lange syndrome (CdLS) is associated with repetitive and self-injurious behaviors (RBs, SIB). Evaluating children with CdLS, this study: (1) characterizes the spectrum of RBs; (2) characterizes the impact and severity of RBs including SIB; (3) describes how age and adaptive functioning relate to RBs including SIB. Fifty children (5-17 years) with CdLS were assessed with Children's Yale-Brown Obsessive Compulsive Scale Modified for PDD; Aberrant Behavior Checklist (ABC); Vineland Adaptive Behaviors Scales (VABS). All children had ≥ 1 type of RB; 44% had some form of SIB. 64% spent > 1 h/day displaying RBs. Lower VABS adaptive functioning was associated with higher stereotypy and SIB scores (ABC). In children with CdLS, RBs including SIB are common, impactful, and associated with lower adaptive functioning.

Profiles of atypical sensory processing in Angelman, Cornelia de Lange and Fragile X syndromes

BACKGROUND

There is growing evidence to suggest that children with neurodevelopmental disorders may evidence differences in their sensory processing. The aim of this study was to compare sensory processing patterns in three genetic syndromes associated with sensory difference.

METHODS

Sensory processing in Angelman syndrome (n = 91), Cornelia de Lange syndrome (n = 28) and Fragile X syndrome (n = 40) was examined using the informant report measure the Sensory Experiences Questionnaire (SEQ).

RESULTS

All three groups were associated with a heightened prevalence of unusual sensory processing in comparison with normative data, evidenced in over 80% of all participants. Cross-syndrome comparisons highlighted syndrome-specific sensory processing profiles, with heightened hypo responsivity in Cornelia de Lange syndrome and sensory seeking in Angelman syndrome.

CONCLUSIONS

The results have important implications for the understanding of sensory processing in genetic syndromes and the development of tailored behavioural interventions.

Discrimination training reduces high rate social approach behaviors in Angelman syndrome: proof of principle

This proof of principle study was designed to evaluate whether excessively high rates of social approach behaviors in children with Angelman syndrome (AS) can be modified using a multiple schedule design. Four children with AS were exposed to a multiple schedule arrangement, in which social reinforcement and extinction, cued using a novel stimulus, were alternated. Twenty-five to 35 discrimination training sessions were conducted and levels of approach behaviors were measured before and after the discrimination training for two children. All four participants evidenced discrimination between conditions of reinforcement and extinction after 16-20 teaching sessions as indicated by lower rates of social approach behaviors in the presence of the S(Δ) for extinction. Reversal effects for the two children for whom this design was implemented were evident. The results demonstrate that after repeated training, the use of a novel stimulus can serve as a cue for children with AS to discriminate adult availability. This is a potentially effective component of a broader intervention strategy but highlights the need for sustained teaching procedures within this population.

Sibling relationships in individuals with Angelman syndrome: a comparative study

OBJECTIVE

Investigating the impact of Angelman syndrome on the sibling relationship.

METHODS

This study explored differences in sibling relationships between children with a typically-developing sibling (n = 55) and children with a sibling with Angelman syndrome (n = 44). Sibling relationships were compared on four factors and 16 sub-scales of the Sibling Relationship Questionnaire-Revised.

RESULTS

Results showed significant differences in mean scores on each of the four factors (i.e. Warmth/Closeness, Conflict, Rivalry and Dominance/Nurturance) and most of the sub-scales. ANCOVAs showed that demographic variables (number of siblings, living in a two-parent vs single parent household, gender, participant's age, place of residence) did not influence significant differences in sibling relationships between the two groups.

CONCLUSION

Having a brother or sister with Angelman syndrome may influence the way in which the sibling perceives the sibling relationship. This may have important implications for family-centred intervention for this population.

Reward circuitry dysfunction in psychiatric and neurodevelopmental disorders and genetic syndromes: animal models and clinical findings

This review summarizes evidence of dysregulated reward circuitry function in a range of neurodevelopmental and psychiatric disorders and genetic syndromes. First, the contribution of identifying a core mechanistic process across disparate disorders to disease classification is discussed, followed by a review of the neurobiology of reward circuitry. We next consider preclinical animal models and clinical evidence of reward-pathway dysfunction in a range of disorders, including psychiatric disorders (i.e., substance-use disorders, affective disorders, eating disorders, and obsessive compulsive disorders), neurodevelopmental disorders (i.e., schizophrenia, attention-deficit/hyperactivity disorder, autism spectrum disorders, Tourette's syndrome, conduct disorder/oppositional defiant disorder), and genetic syndromes (i.e., Fragile X syndrome, Prader-Willi syndrome, Williams syndrome, Angelman syndrome, and Rett syndrome). We also provide brief overviews of effective psychopharmacologic agents that have an effect on the dopamine system in these disorders. This review concludes with methodological considerations for future research designed to more clearly probe reward-circuitry dysfunction, with the ultimate goal of improved intervention strategies.

The behavioral phenotype of Mowat-Wilson syndrome

Mowat-Wilson syndrome (MWS) is caused by a heterozygous mutation or deletion of the ZEB2 gene. It is characterized by a distinctive facial appearance in association with intellectual disability (ID) and variable other features including agenesis of the corpus callosum, seizures, congenital heart defects, microcephaly, short stature, hypotonia, and Hirschsprung disease. The current study investigated the behavioral phenotype of MWS. Parents and carers of 61 individuals with MWS completed the Developmental Behavior Checklist. Data were compared with those for individuals selected from an epidemiological sample of people with ID from other causes. The behaviors associated with MWS included a high rate of oral behaviors, an increased rate of repetitive behaviors, and an under-reaction to pain. Other aspects of the MWS behavioral phenotype are suggestive of a happy affect and sociable demeanor. Despite this, those with MWS displayed similarly high levels of behavioral problems as those with intellectual disabilities from other causes, with over 30% showing clinically significant levels of behavioral or emotional disturbance. These findings have the potential to expand our knowledge of the role of the ZEB2 gene during neurodevelopment. Furthermore, they are a foundation for informing interventions and management options to enhance the independence and quality of life for persons with MWS.

Angelman syndrome: Mutations influence features in early childhood

Angelman syndrome (AS) is a neurodevelopmental disorder caused by a lack of expression of the maternal copy of UBE3A. Although the "classic" features of AS are well described, few large-scale studies have delineated the clinical features in AS. We present baseline data from 92 children with a molecular diagnosis of AS between 5 and 60 months old who are enrolled in the National Institutes of Health Rare Diseases Clinical Research Network Angelman Syndrome Natural History Study from January 2006 to March 2008. Seventy-four percent of participants had deletions, 14% had either uniparental disomy (UPD) or imprinting defects, and 12% had UBE3A mutations. Participants with UPD/imprinting defects were heavier (P = 0.0002), while those with deletions were lighter, than the general population (P < 0.0001). Twenty out of 92 participants were underweight, all of whom had deletions or UBE3A mutations. Eight out of 92 participants (6/13 (46%) with UPD/imprinting defects and 2/11 (18%) with UBE3A mutations) were obese. Seventy-four out of 92 participants (80%) had absolute or relative microcephaly. No participant was macrocephalic. The most common behavioral findings were mouthing behavior (95%), short attention span (92%), ataxic or broad-based gait (88%), history of sleep difficulties (80%), and fascination with water (75%). Frequent, easily provoked laughter was observed in 60%. Clinical seizures were reported in 65% of participants but all electroencephalograms (EEGs) were abnormal. We conclude that the most characteristic feature of AS is the neurobehavioral phenotype, but specific EEG findings are highly sensitive for AS. Obesity is common among those with UPD/imprinting defects.

Adaptive behaviour in Angelman syndrome: its profile and relationship to age

BACKGROUND

Angelman syndrome (AS) is a neurodevelopmental disorder usually caused by an anomaly in the maternally inherited chromosome 15. The main features are severe intellectual disability, speech impairment, ataxia, epilepsy, sleep disorder and a behavioural phenotype that reportedly includes happy disposition, attraction to/fascination with water and hypermotoric behaviour.

METHOD

We studied the level of adaptive behaviour and the adaptive behavioural profile in the areas of 'motor skills', 'language and communication', 'personal life skills' and 'community life skills' in a group of 25 individuals with genetically confirmed AS, to determine whether there is a specific adaptive behaviour profile.

RESULTS AND CONCLUSIONS

None of the individuals, whatever their chronological age, had reached a developmental age of 3 years. A specific adaptive behaviour profile was found, with 'personal life skills' emerging as relative strengths and 'social and communication skills' as weaknesses.

Maternal parenting stress in families with a child with Angelman syndrome or Prader-Willi syndrome

BACKGROUND

Parenting stress was investigated in mothers with a child with Angelman syndrome (AS) or Prader-Willi syndrome (PWS), which are genetically related.

METHOD

Mothers of 24 children with AS and 23 children with PWS (2-12 years) completed the Nijmegen Parenting Stress Index-Short, Developmental Behaviour Checklist, and Vineland Screener 0-12.

RESULTS

Parenting stress was high for 58% of AS and 26% of PWS cases. For both syndromes, no relationship existed with the child's gender, age, or behavioural problems. In PWS there was no effect on level of functioning. Overall, more mothers with a child with AS perceived high parenting stress. When children showed low levels of behavioural problems this difference was contained. However, when children exhibited severe behavioural problems, parenting stress was the same for both syndromes.

CONCLUSION

In AS professional family support is essential, since parenting is stressful for many mothers. In PWS, this is especially the case when behavioural problems are present.

Behavioural flexibility in individuals with Angelman syndrome, Down syndrome, non-specific intellectual disability and Autism spectrum disorder

BACKGROUND

Little is known about behavioural flexibility in children and adults with Angelman syndrome and whether people with this syndrome have more or less problems in being behaviourally flexible as compared with other people.

METHOD

Behavioural flexibility scores were assessed in 129 individuals with Angelman syndrome using 11 items from the Behavioural Flexibility Rating Scale-Revised (Green et al. 2007). Level of behavioural flexibility scores in individuals with Angelman syndrome (N = 129) was compared with that of people with non-specific intellectual disability (ID) (N = 90), Down syndrome (N = 398) and Autism spectrum disorder (N = 235).

RESULTS

Comparative analyses show that individuals with Angelman syndrome were more flexible than those with non-specific ID (P < 0.001) and those with Autism spectrum disorder (P < 0.01). There were no differences in behavioural flexibility scores between individuals with Angelman syndrome and those with Down syndrome (P = 0.94).

CONCLUSION

It is concluded that individuals with Angelman syndrome are comparatively flexible in their behaviour.