Neurocognitive and neurobehavioural characterization of two frequent forms of neurodevelopmental disorders: the DYRK1A and the Wiedemann-Steiner syndromes

Associations Between Executive Functioning, Behavioral Functioning, and Adaptive Functioning Difficulties in Wiedemann-Steiner Syndrome

OBJECTIVES

Wiedemann-Steiner syndrome (WSS) is a neurogenetic disorder caused by heterozygous variants in KMT2A. Recent investigations suggest increased anxiety and behavior regulation challenges among those with WSS although the neurobehavioral phenotype remains largely unknown. This study aims to examine the pattern of and associations between executive functioning (EF) and behavior functioning among those with WSS.

METHOD

This study involved utilizing caregiver-report inventories (Behavior Rating Inventory of Executive Function 2nd Edition, BRIEF-2; Adaptive Behavior Assessment 3rd Edition, ABAS-3; Strengths and Difficulties Questionnaire, SDQ) to assess day-to-day behavior functioning among those with WSS (N = 24; mean age = 10.68 years, SD = 3.19). Frequency of clinical elevations in daily difficulties in EF, adaptive behaviors, and behavior regulation were reported. Correlations and hierarchical linear regressions were used to determine the relationships between EF with behavior and adaptive functioning.

RESULTS

Out of our sample, 63% met clinical levels of executive functioning difficulties on the BRIEF-2, and 75% with Hyperactivity and 54% with Emotional Problems on the SDQ. In addition, 33% were rated >2 SD below the normative mean in overall adaptive functioning on the ABAS-3. Elevated ratings in BRIEF-2 Shift, reflective of challenges with mental flexibility, predicted more Emotional Problems and accounted for 33.5% of its variance. More difficulties in Emotional Control were related to greater adaptive deficits, accounting for 33.3% of its variance.

CONCLUSIONS

Those with WSS are at risk for EF deficits, hyperactivity, and emotional dysregulation. EF correlates with adaptive and affective behaviors, highlighting the promise of behavioral interventions to target cognitive flexibility, emotional awareness, and reactivity in this population.

Attention challenges in Kabuki syndrome

BACKGROUND

Understanding the specific neurobehavioural profile of rare genetic diseases enables clinicians to provide the best possible care for patients and families, including prognostic and treatment advisement. Previous studies suggested that a subset of individuals with Kabuki syndrome (KS), a genetic disorder causing intellectual disability and other neurodevelopmental phenotypes, have attentional deficits. However, these studies looked at relatively small numbers of molecularly confirmed cases and often used retrospective clinical data instead of standardised assessments.

METHODS

Fifty-five individuals or caregivers of individuals with molecularly confirmed KS completed assessments to investigate behaviour and adaptive function. Additionally, information was collected on 23 unaffected biological siblings as controls.

RESULTS

Attention Problems in children was the only behavioural category that, when averaged, was clinically significant, with the individual scores of nearly 50% of the children with KS falling in the problematic range. Children with KS scored significantly higher than their unaffected sibling on nearly all behavioural categories. A significant correlation was found between Attention Problems scores and adaptive function scores (P = 0.032), which was not explained by lower general cognitive ability.

CONCLUSIONS

We found that the rates of children with attentional deficits are much more elevated than would be expected in the general population, and that attention challenges are negatively correlated with adaptive function. When averaged across KS participants, none of the behavioural categories were in the clinically significant range except Attention Problems for children, which underscores the importance of clinicians screening for attention deficit hyperactivity disorder (ADHD) in children with KS.

The social phenotype associated with Wiedemann-Steiner syndrome: Autistic traits juxtaposed with high social drive and prosociality

The aim of this study was to provide a descriptive overview of the social characteristics associated with Wiedemann-Steiner syndrome (WSS). A total of 24 parents of children/adults with WSS (11F, mean age = 12.94 years, SD = 8.00) completed the Social Responsiveness Scale 2nd Edition (SRS-2); Colorado Learning Difficulties Questionnaire (CLDQ) and Strengths and Difficulties Questionnaire (SDQ). Almost half our sample reported a diagnosis of autism spectrum disorder (ASD) and 70% had intellectual disability. On the SDQ, over 90% of participants were rated in borderline/clinical ranges in Peer Problems, yet the majority fell within normal limits in Prosocial Behaviors. Most fell in the moderate/severe difficulties ranges across SRS-2 Social Cognition, Communication, and Restricted/Repetitive Behaviors scales (all >70%); whereas substantially less participants met these ranges for deficits in Social Awareness (50%) and Social Motivation (33.33%). A pattern of relatively strong prosocial skills and social drive in the context of difficulties with inflexible behaviors, social cognition, and communication was observed, regardless of gender, ASD or intellectual disability diagnosis. The social phenotype associated with WSS is characterized by some autistic features paired with unusually high social motivation and prosocial tendencies.

To speak may draw on epigenetic writing and reading: Unravelling the complexity of speech and language outcomes across chromatin-related neurodevelopmental disorders

Speech and language development are complex neurodevelopmental processes that are incompletely understood, yet current evidence suggests that speech and language disorders are prominent in those with disorders of chromatin regulation. This review aimed to unravel what is known about speech and language outcomes for individuals with chromatin-related neurodevelopmental disorders. A systematic literature search following PRISMA guidelines was conducted on 70 chromatin genes, to identify reports of speech/language outcomes across studies, including clinical reports, formal subjective measures, and standardised/objective measures. 3932 studies were identified and screened and 112 were systematically reviewed. Communication impairment was core across chromatin disorders, and specifically, chromatin writers and readers appear to play an important role in motor speech development. Identification of these relationships is important because chromatin disorders show promise as therapeutic targets due to the capacity for epigenetic modification. Further research is required using standardised and formal assessments to understand the nuanced speech/language profiles associated with variants in each gene, and the influence of chromatin dysregulation on the neurobiology of speech and language development.

Characterizing the autism spectrum phenotype in DYRK1A-related syndrome

Likely gene-disrupting (LGD) variants in DYRK1A are causative of DYRK1A syndrome and associated with autism spectrum disorder (ASD) and intellectual disability (ID). While many individuals with DYRK1A syndrome are diagnosed with ASD, they may present with a unique profile of ASD traits. We present a comprehensive characterization of the ASD profile in children and young adults with LGDs in DYRK1A. Individuals with LGD variants in DYRK1A (n = 29) were compared to children who had ASD with no known genetic cause, either with low nonverbal IQ (n = 14) or average or above nonverbal IQ (n = 41). ASD was assessed using the ADOS-2, ADI-R, SRS-2, SCQ, and RBS-R. Quantitative score comparisons were conducted, as were qualitative analyses of clinicians' behavioral observations. Diagnosis of ASD was confirmed in 85% and ID was confirmed in 89% of participants with DYRK1A syndrome. Individuals with DYRK1A syndrome showed broadly similar social communication behaviors to children with idiopathic ASD and below-average nonverbal IQ, with specific challenges noted in social reciprocity and nonverbal communication. Children with DYRK1A syndrome also showed high rates of sensory-seeking behaviors. Phenotypic characterization of individuals with DYRK1A syndrome may provide additional information on mechanisms contributing to co-occurring ASD and ID and contribute to the identification of genetic predictors of specific ASD traits.

Epigenetics of cognition and behavior: insights from Mendelian disorders of epigenetic machinery

Epigenetics, one mechanism by which gene expression can change without any changes to the DNA sequence, was described nearly a century ago. However, the importance of epigenetic processes to neurodevelopment and higher order neurological functions like cognition and behavior is only now being realized. A group of disorders known as the Mendelian disorders of the epigenetic machinery are caused by the altered function of epigenetic machinery proteins, which consequently affects downstream expression of many genes. These disorders almost universally have cognitive dysfunction and behavioral issues as core features. Here, we review what is known about the neurodevelopmental phenotypes of some key examples of these disorders divided into categories based on the underlying function of the affected protein. Understanding these Mendelian disorders of the epigenetic machinery can illuminate the role of epigenetic regulation in typical brain function and can lead to future therapies and better management for a host of neurodevelopmental and neuropsychological disorders.

Novel variants and phenotypic heterogeneity in a cohort of 11 Chinese children with Wiedemann-Steiner syndrome

Objective: Wiedemann-Steiner syndrome (WSS) is a rare autosomal dominant disorder caused by deleterious heterozygous variants of the KMT2A gene. This study aims to describe the phenotypic and genotypic features of Chinese WSS patients, and assess therapeutic effects of recombinant human growth hormone (rhGH). Methods: Eleven Chinese children with WSS were enrolled in our cohort. Their clinical, imaging, biochemical and molecular findings were analyzed retrospectively. Moreover, the phenotypic features of 41 previously reported Chinese WSS patients were reviewed and included in our analysis. Results: In our cohort, the 11 WSS patients presented with classic clinical manifestations, but with different frequencies. The most common clinical features were short stature (90.9%) and developmental delay (90.9%), followed by intellectual disability (72.7%). The most frequent imaging features were patent ductus arteriosus (57.1%) and patent foramen ovale (42.9%) in cardiovascular system, and abnormal corpus callosum (50.0%) in the brain. In the set comprising 52 Chinese WSS patients, the most common clinical and imaging manifestations were developmental delay (84.6%), intellectual disability (84.6%), short stature (80.8%) and delayed bone age (68.0%), respectively. Eleven different variants, including three known and eight novel variants, of the KMT2A gene were identified in our 11 WSS patients without a hotspot variant. Two patients were treated with rhGH and yielded satisfactory height gains, but one developed acceleration of bone age. Conclusion: Our study adds 11 new patients with WSS, reveals different clinical characteristics in Chinese WSS patients, and extends the mutational spectrum of the KMT2A gene. Our study also shares the therapeutic effects of rhGH in two WSS patients without GH deficiency.

GenIDA: an international participatory database to gain knowledge on health issues related to genetic forms of neurodevelopmental disorders

Intellectual disability with or without manifestations of autism and/or epilepsy affects 1-2% of the population, and it is estimated that more than 30-50% of these cases have a single genetic cause. More than 1000 genes and recurrent chromosomal abnormalities are involved in these genetic forms of neurodevelopmental disorders, which often remain insufficiently described in terms of clinical spectrum, associated medical problems, etc., due to their rarity and the often-limited number of patients' phenotypes reported. GenIDA is an international online participatory database that aims to better characterise the clinical manifestations and natural histories of these rare diseases. Clinical information is reported by parents of affected individuals using a structured questionnaire exploring physical parameters, cognitive and behavioural aspects, the presence or absence of neurological disorders or problems affecting major physiological functions, as well as autonomy and quality of life. This strengthens the implication in research of the concerned families. GenIDA aims to construct international cohorts of significant size of individuals affected by a given condition. As of July 2022, GenIDA counts some 1545 documented patient records from over 60 nationalities and collaborates with clinicians and researchers around the world who have access to the anonymized data collected to generate new, medically meaningful information to improve patient care. We present the GenIDA database here, together with an overview of the possibilities it offers to affected individuals, their families, and professionals in charge of the management of genetic forms of neurodevelopmental disorders. Finally, case studies of cohorts will illustrate the usefulness of GenIDA.

Anxiety in Wiedemann-Steiner syndrome

This study examined anxiety in Wiedemann-Steiner syndrome (WSS). Eighteen caregivers and participants with WSS completed the parent- and self-report versions of the Screen for Child Anxiety Related Disorder or the adapted version of the Screen for Adult Anxiety Related Disorder. Approximately 33.33% of parents and 65% of participants with WSS rated in the clinical range for overall anxiety. Across anxiety subtypes, parents primarily indicated concerns with Separation Anxiety (72%), which was also endorsed by the majority of participants with WSS (82%). The emergent trend showed Total Anxiety increased with age based on parent-informant ratings. The behavioral phenotype of WSS includes elevated anxiety. Clinical management should include incorporating early behavioral interventions to bolster emotion regulation given the observed risk of anxiety with age.