Atypical neural variability in carriers of 16p11.2 copy number variants

Copy number variations (CNVs) at the 16p11.2 chromosomal region are associated with myriad clinical features including intellectual disability and autism spectrum disorder. The aim of this study is to determine whether 16p11.2 deletion (DEL) and duplication (DUP) carriers demonstrate a distinct and reciprocal pattern of electroencephalography (EEG) activity as represented by neural variability measures. EEG data were previously collected as part of the Simons Variation in Individuals Project. Variability measures, as estimated by single‐trial ERP and spectral power analyses in the alpha and beta frequency bands, in addition to signal‐to‐noise ratios (SNRs), were analyzed in DEL (n = 20), DUP (n = 8), and typical (n = 11) groups. We also analyzed mean visual evoked potentials and spectral power (alpha and beta power) to facilitate comparisons with other studies of associated disorders and CNVs. From measures of single‐trial variability, we found higher intraparticipant variability in P1 amplitude and timecourse amplitude in DEL compared to controls. Compared to DUP, DEL showed higher variability in absolute alpha and absolute beta power but lower variability in P1 latency. SNRs did not differ between the groups. From measures of amplitude, latency, and spectral power, DUP showed lower relative alpha power compared to controls. Although it is yet unclear whether 16p11.2 CNV dosage impacts neural activity in an opposing manner, findings suggest that 16p11.2 DEL impacts the level of variability of neural responses. Higher neural variability may play a role in a range of cognitive processes in 16p11.2 CNV carriers. Lay Summary The study analyzed the consistency of patterns of brain waves and rhythms in those affected with a loss or gain of DNA material in the 16p11.2 region. Compared with typical individuals, 16p11.2 deletion carriers showed greater inconsistency in the way the brain responds to the same visual event. This high inconsistency in brain activity may play a role in some core symptoms in 16p11.2 copy number variation carriers

Sensory processing in Sotos syndrome and Tatton-Brown–Rahman Syndrome.

Sotos syndrome (Sotos) and Tatton-Brown–Rahman Syndrome (TBRS) are two of the most common overgrowth disorders associated with intellectual disability. Individuals with these syndromes tend to have similar cognitive profiles and high likelihood of autism symptomatology. However, whether and how sensory processing is affected is currently unknown. Parents/caregivers of 36 children with Sotos and 20 children with TBRS completed the Child Sensory Profile-2 (CSP-2) and the Sensory Behavior Questionnaire (SBQ) along with other standardized questionnaires assessing autistic traits (Social Responsiveness Scale, Second Edition, SRS-2), attention deficit hyperactivity disorder (ADHD) traits (Conners 3), anxiety (Spence Children’s Anxiety Scale, Parent Version, SCAS-P), and adaptive behavior (Vineland Adaptive Behavior Scales Third Edition). Sensory processing differences were clearly evident in both syndromes, though there was significant variation in both cohorts. SBQ data indicated that both the frequency and impact of sensory behavior were more severe when compared to neurotypicals, with levels of sensory behavior impact and frequency being similar to autistic children. CSP-2 data indicated 77% of children with Sotos and 85% children with TBRS displayed clear differences in sensory Registration (missing sensory input). Clear differences relating to Body Position (proprioceptive response to joint and muscle position; 79% Sotos; 90% TBRS) and Touch (somatosensory response to touch on skin; 56% Sotos; 60% TBRS) were also particularly prevalent. Correlation analyses demonstrated that in both syndromes sensory processing differences tend to be associated with difficulties relating to autistic traits, anxiety, and some domains of ADHD. In Sotos, sensory processing differences were also associated with lower adaptive behavior skills. This first detailed assessment of sensory processing, alongside other clinical features, in relatively large cohorts of children with Sotos and TBRS, demonstrates that sensory processing differences have a profound impact on everyday life

Sensory processing in 16p11.2 deletion and 16p11.2 duplication

Deletions and duplications at the chromosomal region of 16p11.2 have a broad range of phenotypic effects including increased likelihood of intellectual disability, autism, attention deficit hyperactivity disorder (ADHD), epilepsy, and language and motor delays. However, whether and how sensory processing is affected has not yet been considered in detail. Parents/caregivers of 38 children with a 16p11.2 deletion and 31 children with a 16p11.2 duplication completed the Sensory Behavior Questionnaire (SBQ) and the Child Sensory Profile 2 (CSP-2) along with other standardized questionnaires assessing autistic traits (SRS-2), ADHD traits (Conners 3), anxiety (SCAS-P) and adaptive behavior (VABS-3). SBQ and CSP-2 responses found that sensory processing differences were clearly evident in both 16p11.2 deletion and 16p11.2 duplication, though there was significant variation in both cohorts. SBQ data indicated the frequency and impact of sensory behavior were more severe when compared to neurotypical children, with levels being similar to autistic children. CSP-2 data indicated over 70% of children displayed clear differences in sensory registration (missing sensory input). Seventy-one percent with 16p11.2 duplications were also unusually sensitive to sensory information and 57% with 16p11.2 duplications were unusually avoidant of sensory stimuli. This first detailed assessment of sensory processing, alongside other clinical features, in relatively large cohorts of children with a 16p11.2 deletion and 16p11.2 duplication demonstrates that sensory processing differences have a profound impact on their lives

Impaired communication ability in SOX11 syndrome

Background Speech and language skills are important for social interaction and learning. This study characterised the communication abilities of verbal individuals with SOX11 syndrome using a standardised parent/carer questionnaire, the Children's Communication Checklist (CCC-2). Method Thirteen parent/carers of verbal individuals (aged 5–19 years) diagnosed with SOX11 syndrome completed the CCC-2. In order to contextualise findings, responses were compared to norms and to data from Noonan syndrome, a relatively well-known genetic diagnosis associated with communication impairment. Results For all individuals, the CCC-2 composite score indicated significant communication difficulties. Language structure (speech, syntax, semantics and coherence), pragmatic language (inappropriate initiation, stereotyped language use of context and non-verbal communication) and autistic features (social relations and interests) scores were lower than typically developing norms. Subscale comparisons revealed relative difference in use of context compared to other pragmatic domains (stereotyped language and inappropriate initiation). Individual scores showed substantial variation, particularly in regard to language structure profile. Differences were more pronounced than for Noonan syndrome, specifically in domains of speech, syntax, non-verbal communication and social relations. Conclusions SOX11 syndrome is associated with communication impairment. It is important to assess communication abilities as part of the management of individuals with SOX11 syndrome and understand individual strengths and difficulties in order to provide targeted support

Spontaneous neural activity relates to psychiatric traits in 16p11.2 CNV carriers: An analysis of EEG spectral power and multiscale entropy

Copy number variations (CNV) at the 16p11.2 chromosomal region are rare high-risk CNVs associated with various clinical features and psychiatric disorders including intellectual disability, developmental delays, and autism spectrum disorder. No study to date has investigated whether spontaneous neural activity is altered for 16p11.2 CNV carriers and whether this relates to psychiatric traits. The aim of this study is to examine the impact of 16p11.2 deletions (del) and duplications (dup) on spontaneous neural activity and its relationship to psychiatric problems. EEG was previously collected as part of the Simons Searchlight initiative. Using spectral power (delta, theta, alpha, and beta frequency bands), complexity index (CI), and multiscale entropy analysis techniques, we analyzed frontal resting-state EEG data collected from 22 16p11.2 del carriers, 14 dup carriers, and 13 controls. We then examined associations between neural activity and psychiatric traits, measured with the Child Behavior Checklist. Results indicated that EEG entropy was higher for del and dup compared to controls, respectively, at all timescales. CI was also higher for del and dup compared to controls. Theta power of 16p11.2 dup carriers was higher than controls. A strong association was found between entropy at higher timescales and anxiety problems. In addition, a strong correlation was found between theta power and pervasive developmental problems. Atypical spontaneous neural activity is implicated in 16p11.2 CNVs. With higher entropy or theta power, psychiatric traits increase in severity. Our findings provide evidence of the link between genotype, neural activity, and phenotypes in 16p11.2 CNVs

Short report: Behavioural characterisation of SOX11 syndrome

Background: SOX11 syndrome is a rare condition caused by deletions or de novo point mutations of the SOX11 gene. SOX11 is a transcription factor gene that plays an important role in brain development. Aims: The aim of this study was to quantitatively evaluate the behavioural profiles of individuals with SOX11 syndrome. Methods and procedures: The Vineland Adaptive Behaviour Scales 3 (VABS-3) and the Social Responsiveness Scale 2 (SRS-2) were completed by parents of 21 children and young adults with SOX11 syndrome. Outcomes and results: Most were found to have borderline (33%) or mild (39%) impairment in adaptive behaviour, with more difficulties in communication and daily living than socialisation in the cohort overall. Most (90%) were found to exhibit clinically relevant levels of autistic traits, with 62% scoring in the “severe” range, though social motivation was observed to be a relative strength in the cohort overall. Conclusions and implications: This study presents the first standardised evaluation of adaptive behaviour and autistic traits of individuals with SOX11 syndrome. This will improve clinicians, educators and parents’ understanding of SOX11 syndrome