Molecular Autism

Autism is a common neurodevelopmental condition with considerable between-person variability and unknown biological etiology. Diagnosis of autism in adults relies on measurement of performance (e.g., clinician rating of social behavior, standardized assessment of cognition) and self-report of autism features. Our prior work revealed a strong relationship between clinician ratings of social function in autism and in vivo measures of synaptic density as measured by [11C]UCB-J PET (Matuskey et al., 2025). However, it is not understood how the measured aspects of the autism phenotype index underlying biology. Here, in a sample of 12 autistic adults, we address this question by relating synaptic density imaging to a range of performance measures, such as cognition and face recognition, in contrast to self-report measures. Our results identify a dissociation between these measurement types in that synaptic density correlates strongly with measures of performance but shows virtually no relationship with self-report. These findings suggest that, while self-report and performance measures share variance in characterizing phenotypes in autism, they diverge when mapping onto the underlying biology. Results suggest that higher synaptic density may index a general mechanism that facilitates social and cognitive performance across a range of tasks. These data also indicate that performance and self-report measures are not interchangeable in capturing brain-behavior correspondences in autism, a finding that can guide measure selection in future biomarker studies and clinical research.

Background: Helsmoortel-Van der Aa syndrome, caused by pathogenic variants in ADNP, is characterised by substantial clinical heterogeneity, but how biological sex influences disease biology and treatment response remains an emerging area of investigation. Here, we investigated whether sex modifies the behavioural and molecular consequences of Adnp deficiency, the response to the investigational drug candidate davunetide (NAP), and the clinical phenotype of Helsmoortel-Van der Aa syndrome. Methods: We studied male and female Adnp heterozygous mice harbouring the p.Leu822Hisfs*6 variant and sex-matched wild-type littermates using continuous 24-h behavioural phenotyping, hippocampal genome-wide DNA methylation and bulk RNA sequencing. NAP effects on behaviour, hippocampal ADNP protein abundance, and epi-transcriptomic responses were assessed using genotype-by-treatment models. Four Core Genotypes mice were assessed to distinguish sex-chromosome and gonadal contributions to hippocampal Adnp transcript expression, and reproductive-tissue transcriptomes were analysed in Adnp mice to unravel a possible endocrine component of the disease. Findings were compared with clinical and developmental data from 129 individuals with Helsmoortel-Van der Aa syndrome. Findings: Adnp deficiency produced a shared overall behavioural phenotype in male and female mice, but through distinct patterns of behavioural disruption, indicating that sex modifies the implementation rather than the magnitude of the phenotype. This distinction was also evident at the molecular level: hippocampal DNA methylation was predominantly determined by genotype and showed convergence between sexes, whereas transcriptional responses diverged, with mitochondrial pathways predominating in males and chromatin, RNA processing, and cell-cycle pathways in females. NAP partially shifted behavioural abnormalities towards the wild-type state in both sexes and increased hippocampal ADNP protein abundance in heterozygous mice, without reversing the underlying methylation phenotype. Its transcriptional effects were markedly broader in males, indicating a sex-dependent molecular response to treatment. In reproductive tissues, Adnp deficiency was associated with convergent alterations in steroid hormone biosynthesis, despite no evidence for direct regulation of hippocampal Adnp expression by sex-chromosome complement or gonadal hormonal state. By contrast, sex was not associated with robust differences across the clinical and developmental features assessed in 129 individuals with Helsmoortel-Van der Aa syndrome after correction for multiple testing. Interpretation: Biological sex modifies how Adnp deficiency is expressed at behavioural and molecular levels, but these differences do not necessarily define distinct clinical phenotypes. The convergence of the methylation response alongside greater divergence in transcriptional and behavioural responses identifies sex as a modifier of disease biology rather than a determinant of the core phenotype. The sex-dependent response to NAP further indicates that biological sex may influence pharmacological responses even when treatment-associated behavioural improvement is observed in both sexes. These findings support consideration of biological sex as a prespecified variable in preclinical and clinical studies of Helsmoortel-Van der Aa syndrome and suggest that systematic investigation of sex-dependent biology may also be relevant to therapeutic development across rare diseases. Keywords: Helsmoortel-Van der Aa syndrome (HVDAS), Activity-Dependent Neuroprotective Protein (ADNP), autism spectrum disorder, intellectual disability, sex, mouse model, behaviour.

Altered sensitivity to sounds despite normal peripheral hearing is common in neurodevelopmental disorders but the underlying mechanisms remain poorly understood. Here we investigate tonotopic organization in 86 children (6-11 years) with autism spectrum and related neurodevelopmental disorders as well as typically developing (TD) peers, using a child-friendly, passive listening, functional magnetic resonance imaging design. In TD children, tonotopic maps in primary auditory cortex resembled the typical high-low-high frequency gradients previously reported in adults, while children with autism showed an overrepresentation of high frequencies consistent with what has been observed in animal models of autism. Higher frequency tuning further correlated with greater caregiver-reported sound but not touch sensitivities. Importantly, tonotopy is a core organizational feature of auditory cortex that develops early in life and remains relatively stable after the critical period of heightened plasticity ends. Thus, these results suggest that atypical auditory processing in autism may result from early disruption to tonotopic map formation. Longitudinal neuroimaging studies are needed to understand the genetic and environmental causes of altered auditory cortex topology and its long-term consequences for higher-level auditory, language, and social communication development.

Autistic individuals with intellectual disability (ASD+ID) and profound autism are rarely studied in neuroscience research due to barriers including communication challenges, sensory sensitivities, anxiety, and elevated behavioral support needs. Consequently, biomarker development in autism fails to include the portion of the autistic population with highest support needs and greatest potential to benefit from treatments derived from imminent advances in personalized medicine. Here we present a multimodal, participant-centered protocol for simultaneous electroencephalography (EEG) and eye-tracking (ET) acquisition to advance clinical trial readiness research in this underserved population. The protocol combines individualized behavioral supports and an adaptive EEG-ET acquisition platform. Pre-visit caregiver interviews informed participant-specific research plans, including customized visual supports, reinforcement strategies, and EEG net desensitization procedures. A gaze-contingent stimulus presentation system used participant-preferred videos to support attention to experimental stimuli and behavior consistent with data acquisition (e.g., refraining from movement) while dynamically adapting stimulus delivery based on visual engagement with the assay and real-time assessment of data quality. By quantifying attended trials in real time and prioritizing unattended stimulus classes, the paradigm maximizes acquisition efficiency to minimize participant burden. This approach was utilized to deploy candidate biomarkers with demonstrated replicability in the Autism Biomarkers Consortium for Clinical Trials (ABC-CT): the N170 event-related potential to faces, resting-state EEG, and visual attention to human faces (measured with ET). Feasibility was evaluated in 76 children with ASD+ID (M age = 8.76 years; IQ = 32.4) and a small comparison sample of 8 children with intellectual disability without autism (M age = 8.91 years; IQ = 45.9). Usable EEG data (>7 minutes) were acquired in 61% (ASD+ID) and 88% (ID) of participants, respectively. Sufficient ET data were obtained from 67% (ASD+ID) and 63% (ID) of participants, respectively. Findings demonstrate the feasibility of inclusive biomarker acquisition and provide a framework for expanding participation of individuals with ASD+ID and profound autism in neuroscience research. Ongoing research seeks to evaluate this approach in larger samples and to demonstrate feasibility in multisite research studies.

Pharmacological treatments targeting core autistic features remain limited. In neurotypical adults, cannabidiol (CBD) alters mismatch negativity (MMN), an electrophysiological marker of automatic auditory deviance detection that has been associated with autistic traits. The effects of CBD on MMN, as measured using electroencephalography (EEG), in autistic children remain unknown. This secondary analysis of a pilot randomised, double-blind, placebo-controlled crossover trial examined the effects of 12 weeks of oral CBD oil on MMN during a duration-deviant auditory oddball task. We hypothesised that CBD would produce more negative MMN amplitudes and shorter peak latencies relative to placebo. Nineteen autistic children (6-12 years, 8 female) received CBD (dose) and placebo in randomised order, separated by an 8-week washout. Age-adjusted linear mixed-effects models tested Time (baseline, follow-up) x Treatment (CBD, placebo) effects on mean MMN amplitude and peak latency separately at Fz and FCz. Exploratory Spearman correlations examined baseline associations between MMN and Developmental Behaviour Checklist-2 (DBC-2) Social Relating scores. At FCz, latency decreased following CBD but increased following placebo but did not survive FDR correction (p = .029, pFDR = .058) and no other interactions were significant. Higher baseline DBC-2 Social Relating scores were associated with more negative MMN amplitude at FCz (rho = -.58, pFDR = .028) and Fz (rho = -.59, pFDR = .028). These findings provide tentative evidence that CBD may modulate MMN latency in autistic children. Larger trials should clarify CBDs effects on MMN and further examine the association between MMN amplitude and social-relating difficulties.

Background: Autism spectrum disorder (ASD) is neurobiologically heterogeneous, and group comparisons may mask effects confined to subgroups. We tested whether distinct biotypes exist within ASD using unsupervised clustering of multimodal MRI. Methods: We analyzed 149 participants with ASD and 129 typically developing (TD) controls from the Autism Brain Imaging Data Exchange II (6 sites; age 5 to 64 years). Site-harmonized features comprised free water (FW), tissue anisotropy and diffusivity, diffusion tensor image analysis along the perivascular space (DTI-ALPS), cerebrospinal fluid (CSF) volumes and exploratory resting-state regional homogeneity. ASD participants were clustered with k-means using global (7 features) and regional (17 features) sets, with robustness tested by permutation and two further algorithms. TD participants were projected post hoc to test specificity. A composite imaging score was related to Social Responsiveness Scale (SRS) subscales, symptom severity and IQ using partial correlations with false discovery rate correction. Results: Clustering identified an elevated free-water (EFW) biotype comprising approximately 10% of ASD participants, defined by markedly increased FW (d = +4.91 versus remaining ASD participants), reduced tissue anisotropy, reduced DTI-ALPS and enlarged ventricles. It was recovered across feature sets and algorithms (permutation p < .0001) and departed from TD norms, unlike the remaining ASD participants. The composite score correlated with social-perceptual and communicative SRS subscales, most strongly social awareness (r = +0.253, q = .026), but not with symptom severity or IQ. FW related to social motivation in children and adolescents (r = +0.287, q = .037) but not adults. Limitations: Each person was scanned once, so we cannot tell whether these brain differences cause social difficulties or how they change with age. The subgroup was small, clinical data were incomplete, the sample was mostly male with a wide age range, and the findings await confirmation in an independent group. Free water can reflect inflammation, swelling or tissue loss, so its biological meaning remains uncertain. Conclusions: We identify an ASD subgroup defined by extracellular fluid excess and altered white matter that is associated with greater social difficulties. If replicated, this signature may help stratify autistic individuals in mechanistic studies and clinical trials.

Background Autism spectrum disorder (ASD) and Intellectual disability (ID) share an in-creased male prevalence, but the biological mechanisms underlying this male bias remain poorly understood. Mice deficient for CC2D1A, a protein scaffold mutated in ASD/ID, have shown multiple male-specific deficits both in ASD-like behaviors and in the regulation of neuronal intracellular signaling pathways. However, previous re-search relied on conditional knockout (cKO) models due to early postnatal lethality of global Cc2d1a KO strains. Thus, the ability to define the developmental impacts of CC2D1A LOF in mice has been limited. While generating a Cc2d1a knock-in strain with V5-HA epitope tags, we found that homozygous animals (Cc2d1aVH/VH) resulted in a hypomorph line that can be used to study developmental loss of CC2D1A. Methods We assessed gross morphology, behavior, and intracellular signaling in male and female Cc2d1aVH/VH animals, where only ~20% of CC2D1A is present. We then crossed this line with a null allele to obtain a more severe hypomorph (Cc2d1a-/VH) and explore phenotypic penetrance thresholds. In addition to the previous phenotypic characterization, we also assessed body composition, feeding, and molecular hall-marks of metabolic function in both sexes. Results We found that ~80% CC2D1A reduction in Cc2d1aVH/VH mice did not recapitu-late any of the behavioral or molecular disruptions seen in cKO models. In contrast, ~90% CC2D1A reduction in Cc2d1a-/VH mice resulted in ASD/ID-like behavioral phe-notypes in males, similar to those reported in cKO lines, with distinct intracellular sig-naling disruptions. Male and female Cc2d1a-/VH mice also showed subtle but signifi-cant adult weight deficits associated with distinct metabolic changes. Limitations These models still do not fully recapitulate the complete CC2D1A LOF found in patients. Due to the analysis of two independent strains over multiple metrics, these studies are not powered to compare statistical differences between sexes and data were analyzed in males and females independently. Conclusions We identified a strikingly narrow CC2D1A expression threshold for the emer-gence of ASD/ID-like behavioral deficits in males. In addition, we revealed a novel role for CC2D1A in adult weight gain. These mouse strains will be useful to better under-stand CC2D1A LOF phenotypes.

Background Elevated resting gamma power is a reproducible, robust neurophysiology marker across species in fragile X syndrome (FXS), a major known cause of autism spectrum disorders (ASD). In FXS, this neurophysiological phenotype is well described and particularly prominent in males harboring fully methylated full CGG repeat expansions. However, gamma power evaluations in idiopathic ASD have yielded variable results. As a single-gene model of ASD, FXS hold promise to biologically model some of the autism spectrum. Exaggerated gamma power in FXS is thought to reflect increased cortical excitability, a common feature of ASD, and has been shown to correlate with symptoms in both human FXS individuals and the Fmr1 knockout mouse model of FXS. A recent clinical trial of the BK channel positive modulator, Codabakalner, provided encouraging signs that normalization of gamma power in FXS may provide therapeutic benefit [14]. Interventional and biomarker studies in ASD provide support that this may also be the case in ASD. We utilized gamma band power to evaluate neurophysiological overlap between ASD and FXS seeking to determine the prevalence and clinical characteristics of those with ASD who exhibit a FXS-like elevated resting state gamma phenotype. Methods This cross-sectional resting EEG analysis included 159 individuals with non-syndromic ASD and 41 males with fully methylated full mutation FXS. Relative gamma power was calculated as 30-100 Hz power divided by 1-100 Hz power across 10-20-equivalent electrodes, excluding 55-65 Hz. We defined the cutoff for elevated resting gamma band power in ASD as relative gamma power of greater than or equal to the median minus one standard deviation of gamma power in our FXS male sample. Results A FXS-derived relative-gamma threshold of 0.185 or greater was met by 22% of participants with ASD (n=35). As expected, the mean ASD group resting state gamma was lower than the male FXS sample (p < 0.001). ASD participant threshold proportions by age group were 3/37 (8.1%) below 13 years, 9/50 (18.0%) age 13-18 years, and 23/72 (31.9%) in the 18+ years group. Within the ASD group, there were no observable clinical characteristics that readily differentiated participants with an elevated gamma phenotype from those without this phenotype. Conclusions Approximately one fifth of all participants and slightly over 30 percent of adults with ASD met the FXS-derived elevated resting gamma band power criterion. This represents the first investigation using a translational brain neurophysiology marker in a syndromic form of autism to parse a clinical idiopathic ASD sample to identify potential overlapping brain features. The results will work to support potential targeting of ASD subgroups in the future utilizing therapeutic approaches initially established in a single-gene form of developmental disability.

Neuroimaging studies identify the superior temporal sulcus (STS) as an anatomical and functional target in autism spectrum disorder (ASD). Yet, the STS is a heterogeneous structure containing unique subregions, such as the superior temporal asymmetrical pit (STAP), which is a recently identified human-specific landmark. To date, no study has compared the STAP between ASD individuals and neurotypical controls (NTs) in a large sample. Here, we analyzed the mean intra-hemispheric sulcal depth and inter-hemispheric laterality of the STAP, as well as the anterior and posterior portions of the STS (aSTS, pSTS), in 100 NTs and 100 ASD male individuals (ages 5-18) using a discovery-replication design. Across samples, the STAP and pSTS showed rightward asymmetry, while the aSTS showed leftward asymmetry within groups. All features of the STAP, aSTS, or pSTS did not differ significantly between groups. However, pSTS laterality related to individual differences in social cognition, which was further supported by a meta-analysis across over 200 studies showing that neurocognitive functional differences associated with social cognition and ASD are restricted to portions of the STS outside of the STAP. Together, these findings provide fine-grained insight into prior studies showing coarse morphological differences of the STS between individuals with ASD and NTs, as well as open up new questions and new neuroanatomical targets of the heterogeneous STS in future studies of brain structure, brain function, and cognition in ASD, as well as other neurodevelopmental disorders targeting the superior temporal cortex.

Background Autism spectrum disorder (ASD) shows wide phenotypic variation, from adults without intellectual disability and with low support needs to minimally verbal children with intellectual disability and severe behavioral symptoms. Genetic studies of this heterogeneity have focused mainly on high-impact de novo variants and polygenic scores; here we investigate, at the molecular level, the role of common variants. Materials and methods We analyzed genotypic and phenotypic data from 9,332 individuals with ASD in the SPARK cohort. We considered 31 traits: six latent factors derived from the Social Communication Questionnaire and the Repetitive Behavior Scale-Revised, 22 co-occurring diagnoses, parent-reported IQ range, age at diagnosis, and age at first walking. We performed within-case genome-wide association studies (GWAS) and, for the 10 traits with evidence of SNP heritability, association analyses with genetically predicted gene and protein expression, splicing, and enhancer activity in brain and blood (xWAS). Nominated genes were tested for enrichment in biological processes, brain cell types, and developmental stages. xWAS-derived transcriptional signatures were compared with chemical perturbation signatures from CMap/LINCS L1000 to prioritize candidate drugs. Results GWAS identified seven genome-wide significant loci for five traits, including loci near GABRG3 and TENM2 associated with co-occurring sleep, feeding or toileting problems. xWAS identified seven gene-trait associations involving three phenotypes (FDR < 0.1), including CACNA1G with communication skills and NEGR1 with learning disability. GWAS and xWAS nominated different genes which however converged on synaptic transmission and gated channel activity, with preferential expression in neurons during later stages of brain development. PARP and p38 MAPK inhibitors were predicted to reverse the signatures of both social-communication and repetitive-behavior phenotypes, whereas several compound classes, including histone deacetylase inhibitors and mTOR inhibitors, were predicted to reverse the signatures of some phenotypes while mimicking those of others. Conclusion Combining within-case GWAS with xWAS nominates candidate genes mediating common-variant effects on ASD heterogeneity, provides biological insight, and suggests candidates for phenotypically stratified drug repositioning.

TBR1 haploinsufficiency causes a neurodevelopmental disorder associated with intellectual disability and autistic features, but the therapeutic potential of postnatal gene replacement remains incompletely defined. Here, we evaluated adeno associated virus (AAV) mediated human TBR1 replacement in Tbr1 haploinsufficient mice. A single retroorbital injection of AAV.PHP.eB expressing human TBR1 under the human synapsin promoter was administered at postnatal day 3 at a dose of 2 E11 vector genomes. Compared with control vector treated mutants, treated mice exhibited increased TBR1 protein abundance and TBR1, CTIP2, and parvalbumin positive cell counts in selected brain regions. Treatment improved sociability, social transmission of food preference, and buried food seeking. Electroencephalographic (EEG) recordings showed attenuation of elevated relative theta power and improved theta suppression and gamma enhancement during social interaction. However, anterior commissure abnormalities persisted, correction of other EEG abnormalities was incomplete, and sleep wake proportions showed no significant treatment improvement. These findings demonstrate that neonatal TBR1 replacement improves selected behavioral and electrophysiological outcomes despite persistent anatomical abnormalities. These findings support further development of gene replacement for TBR1 haploinsufficiency and highlight EEG measures as candidate biomarkers for monitoring treatment response.

Autism spectrum disorder (ASD) is a common neurodevelopmental disease with no currently effective treatments. In this study, Xenon (Xe), a noble gas used clinically as an anesthetic and a neuroprotectant, has been investigated for its potential therapeutic effects in ASD. Two genetic ASD mouse models (Mef2c mutant and Shank3-/- mice) were exposed to a low concentration of xenon (25%) mixed with oxygen (30%) and balanced with nitrogen for a single exposure of 30 min or for 10 min per day for 10 days. These Xe exposure paradigms rescued ASD-like behaviors in both male and female mice. The behavioral improvements persisted for up to 10 days following termination of the 10-day exposure paradigm. Mechanistically, Xe reduced glutamic acid decarboxylase expression in the inhibitory neurons (verified with RNAseq) of the paraventricular thalamic nucleus (PVT) and decreased GABA release during social interaction. Targeted infusion of the GABAA receptor agonist muscimol into the PVT abolished the Xe-mediated behavioral improvements. Reduced GABAergic transmission following Xe exposure increased PVT glutamatergic neuronal activity. Chemogenetic inhibition of these neurons eliminated the therapeutic effects of Xe, whereas chemogenetic activation mimicked the Xe-induced behavioral improvements. Furthermore, opto-inhibition of PVT glutamatergic projections to the central amygdala (CeA) blocked Xe-mediated behavioral improvement. Opto-activation of the PVT-CeA glutamatergic circuit reversed ASD-like behaviors. These findings demonstrate that Xe ameliorates ASD-like phenotypes in mouse models by modulating the PVT Glu-CeA circuit, supporting Xe as a novel potential therapy for ASD.

Objective: Mental health challenges are highly prevalent in autism, but the degree to which they are similar in experience and etiology to the general population remains unclear. This study's objective was characterization of phenotypic and genetic architectures of psychiatric symptomatology in versus out-of-autism. Methods: Psychiatric symptoms were evaluated using the Child Behavior Checklist (CBCL) in 22,152 children (8-15 years): 11,111 autistic children with verbal abilities from SPARK and 11,041 non-autistic children from ABCD. The CBCL's canonical, population-wide factor structure and genetic associations were compared between cohorts. In parallel, exploratory factor analysis was conducted in SPARK, with resulting dimensions associated with key clinical phenotypes (cognitive ability, co-occurring neuropsychiatric diagnoses), polygenic scores (PGS) for psychiatric disorders, and de novo burden in autism-associated genes. Results: Confirmatory factor analysis supported the canonical structure in ABCD but not in SPARK. Psychiatric PGS associations with canonical CBCL subscales were weaker in SPARK than in ABCD, with the ADHD PGS association to Attention problems lower in SPARK ({beta}=0.05 [CI: 0.04,0.06] than in ABCD ({beta}=0.17 [0.13,0.21]). SPARK exploratory factor analysis replicated canonical internalizing factors while revealing other structural departures, including a distinct Developmental Delays factor and dispersion of social problems across multiple factors. The Developmental Delays factor had the strongest associations with de novo burden and lower cognitive ability but was weakly associated with psychiatric PGS. In contrast, common genetic variation explained larger proportions of variances in somatic and inattentive factors and had stronger PGS associations. Conclusions: Correlation structures and genetic architectures of psychiatric symptoms differed in autism compared to the broader population, emphasizing the need for autism-specific approaches in assessment and treatment.

Genetic loss-of-function (LoF) variants in SCN2A, a gene encoding the voltage-gated sodium channel Nav1.2, have been identified as one of the foremost monogenic causes of autism spectrum disorder (ASD). ASD encompasses a broad spectrum of behavioral phenotypes, with impaired sociability as a core characteristic. We have established Scn2a-deficient mice (Scn2agt/gt) to model Scn2a-related ASD and found that this model recapitulates social impairment, exhibiting severe social deficits. Scn2agt/gt mice exhibit neuronal hyperexcitability and a marked global reduction in potassium channel expression, which plays a crucial role in maintaining the resting membrane potential and repolarizing neurons after an action potential. Among these downregulated potassium channels, potassium voltage-gated channel subfamily A member 1 (Kv1.1) was one of the most affected. To explore whether Kv1.1 could be a potential therapeutic target in SCN2A-related ASD, we evaluated the in vivo efficacy of a genetic construct driven by the CaMKII promoter that allows for exogenous expression of human Kv1.1 (hKv1.1) in principal neurons. In Scn2agt/gt mice, we found that hKv1.1 expression normalizes neuronal hyperexcitability. Importantly, doxycycline-induced hKv1.1 expression enhances sociability in Scn2a-deficient mice without influencing social behavior in wild-type mice, and this effect was reversed upon doxycycline withdrawal. Overall, we demonstrate the successful use of an inducible AAV-mediated gene delivery system to supplement hKv1.1 expression to mitigate neuronal hyperexcitability and ameliorate social impairments in a mouse model of SCN2A-related ASD. These findings highlight the contribution of Kv1.1 to SCN2A-associated pathophysiology and its potential as a therapeutic target for severe social deficits.

Abstract Autistic young adults experience substantial gaps in services supporting community living and participation. The Community Autism Peer Support (CAPS) program is a community-based intervention in which trained autistic peer specialists provide individualized support to autistic young adults pursuing self-determined goals related to community participation and independent living. We conducted a single-site, two-arm randomized controlled trial to evaluate the feasibility of implementing the CAPS program. Forty autistic adults aged 18 to 30 years were randomized to CAPS (n = 20) or services as usual alone (n = 20) and assessed at baseline, 3 months, and 12 months. Study findings showed that CAPS attracted autistic young adults with diverse demographic and diagnostic backgrounds, and most intervention participants remained engaged in services for extended periods. While the study was underpowered to detect statistical differences in outcomes because it was not a main focus of the research, a consistent pattern of results favored the CAPS condition across all outcomes. The largest positive signals were observed for overall and social quality of life, with additional favorable changes in internalized stigma, unmet needs, social functioning, loneliness, and positive autistic identity. Findings provide support for the feasibility and promise of an autistic-delivered peer specialist model focused on community living and participation. The consistent pattern of favorable changes supports continued development of CAPS as a person-centered approach to addressing outcomes important to autistic adults.

We evaluated whether participant-separated within-cohort discrimination was retained when electroencephalography (EEG) classifiers for attention-deficit/hyperactivity disorder (ADHD) were applied to a different population and recording task. This exploratory reanalysis included 121 children performing a visual task and 79 adults recorded during eyes-open rest after basic channel screening. Both cohorts used Cz/F4, 128 Hz, and the first fifteen non-overlapping 2-second epochs per participant. Fixed logistic regression and random forest classifiers used spectral, amplitude-derived, and combined features. Internal evaluation used five repetitions of five-fold participant-grouped cross-validation; bidirectional transfer fitted transformations and classifiers only on the source cohort. Adult spectral balanced accuracy (BA) was 0.9519-0.9546, compared with 0.5504-0.5664 in children. Adult spectral logistic regression exceeded all 999 internal label permutations (Monte Carlo p=0.001; within-family Holm-adjusted p=0.002). Paired spectral-minus-amplitude conditional intervals excluded zero in adults but spanned zero in children. Cross-cohort spectral BA was 0.3584-0.4675, with area under the receiver operating characteristic curve (AUC) of 0.0309-0.3857 in the unchanged score direction. Increasing pediatric source-epoch budgets moved random-forest AUC toward 0.5, whereas logistic-regression AUC remained below 0.1. Strong adult internal discrimination thus coexisted with reverse cross-cohort ranking. These findings characterize the evaluated pipelines, not clinical diagnostic utility or a unique mechanism: age, task, and acquisition differences were not separated, target results had previously been inspected, and conditional intervals excluded model-refitting uncertainty.

The FoxP family of transcription factors has been linked to neurodevelopmental disorders. FoxP1 and FoxP2 were identified as genes associated with autism spectrum disorders (ASD). FoxP1, FoxP2, and FoxP4 are expressed in many brain regions, including the cerebellum that has been of particular interest in the context of ASD. However, their role in the development of the peripheral nervous system (PNS) has been neglected. In view of the fact that a majority of ASD patients show some signs of sensory perception deficits that could go beyond the central nervous system, we focused on neural circuit formation in the PNS. Our in vivo and in vitro studies revealed a role of all three FoxP transcription factors in neural circuit formation in the hindlimb of the chicken embryo. Silencing of FoxP genes altered motor axon guidance and also impacted neural crest cell migration. This in turn resulted in aberrant formation of dorsal root ganglia and deficits in neural circuits in the PNS. Taken together, our results are in line with the hypothesis that some of the sensory perception deficits in ASD patients, either hyper- or hyposensitivity, are due to aberrant neural circuits in the PNS.

Growing evidence supports neuroinflammation as a risk factor for neurodevelopmental and psychiatric disorders. Interleukin 6 (IL-6), a classical pro-inflammatory cytokine, has been associated with autism spectrum disorder (ASD)-related phenotypes. To better understand molecular factors that modify neuronal cytokine responses in ASD, we investigated potential roles for JAKMIP1, a gene linked to chromosome 15q-duplication syndrome (Dup15q; a form of syndromic ASD), in regulating IL-6/STAT3 signaling. We observe that JAKMIP1 deficiency impairs IL-6/STAT3 signaling and IL-6-induced neuritogenesis in SH-SY5Y cells; and discover that JAKMIP1 may regulate STAT3 expression via its C-terminus, which exhibits nucleoplasmic localization. Additionally, we find that IL-6/STAT3 signaling is altered in Dup15q hiPSCs-derived cortical neurons, which display heightened responsiveness to IL-6; though it is unclear whether and how JAKMIP1 contributes to this. Overall, our findings identify JAKMIP1 as a modulator of neuronal IL-6/STAT3 signaling and support that ASD-linked genetic variants can alter the inflammatory landscape of ASD.

BackgroundThe balance between excitatory and inhibitory neuronal signalling (E/I balance), proposed as a key mechanism controlling neuronal activity, is disrupted in many neurodevelopmental conditions. One such condition is Neurofibromatosis Type 1, a monogenic neurodevelopmental disorder characterised by increased inhibitory tone. While previous research suggests that E/I balance may be altered in infancy, it is unknown whether E/I balance remains altered during adolescence in NF1. Here we investigated this question using the aperiodic exponent of the resting electroencephalogram (EEG) power spectrum, a proposed electrophysiological index of E/I balance. MethodThe aperiodic exponent of the EEG power spectrum ( 1/f) was estimated for 16 adolescents with NF1 diagnosis aged 11-16, and 16 age- and sex-matched neurotypical controls. General linear models (GLM) were fit to estimate effects of NF1 diagnosis, age and their interaction on aperiodic exponent. We also estimated the peak dominant frequency and power in oscillatory activity of the EEG signal and fitted the same structure of GLM models. Cognitive assessments across domains of memory, executive function and attention were also analysed with GLM to examine brain-cognition associations. ResultsThe NF1 group had higher aperiodic exponent compared to neurotypical controls, but the aperiodic exponent was not associated with cognitive performance. After accounting for aperiodic activity, the NF1 group also had lower dominant oscillatory frequency than the control group. There was no significant interaction between NF1 diagnosis and age on PAF. There were no group differences in peak alpha power. ConclusionsWe demonstrate for the first time that the alterations to aperiodic activity in NF1 are consistent with the proposed mechanism of increased inhibitory tone. These findings show the potential of this paradigm for future pharmacological and brain stimulation trials investigating treatment-related changes in cortical function.

3q29 deletion (3q29Del) is a genetic risk variant for autism spectrum disorder and schizophrenia that often results in developmental delays, cognitive disability, and impaired fine motor function. People with 3q29Del have reduced cerebellar volume, which correlates with symptom severity, and many 3q29Del-associated phenotypes also commonly occur after cerebellar injury or dysfunction. However, it is unknown whether the existing 3q29Del mouse model recapitulates the cerebellar dysfunction observed in humans. To characterize cerebellar phenotypes and uncover pathological differences in the 3q29Del mouse model, we investigated cerebellar structure, motor and vocal behaviors, protein expression, and mitochondrial function. We found uniformly reduced cerebellar volume in 3q29Del mice. Behavioral assays revealed vocal impairments in 3q29Del pups, fine motor impairments in adult mice, and reduced social mating calls in adult male mice. Proteomic analysis revealed enrichment of synaptic and mitochondrial proteins among the differentially expressed proteins in 3q29Del cerebellum tissue. Furthermore, mitochondria from 3q29Del mouse cerebellum displayed reduced oxygen flux and increased electron leak. These results recapitulate many human 3q29Del phenotypes in the 3q29Del mouse model and indicate mitochondrial dysfunction as a potential driver of 3q29Del pathology. Our findings also point to cerebellar involvement in 3q29Del phenotypes and provide a foundation for further research on cerebellar development in 3q29Del.