Reversed gender ratio of autism spectrum disorder in Smith-Magenis syndrome

Speech, Language, Hearing, and Otopathology Results From the International Smith-Magenis Syndrome Patient Registry

PURPOSE

Smith-Magenis syndrome (SMS), a rare, genetically linked complex developmental disorder caused by a deletion or mutation within chromosome 17p11.2, is associated with delays in speech-language development, otopathology, and hearing loss, yet previous studies lack comprehensive descriptions of hearing and communication profiles. Here, analyses of patient registry data expand what is known about speech, language, hearing, and otopathology in SMS.

METHOD

International speech-language and hearing registry survey data for 82 individuals with SMS were analyzed using descriptive and inferential statistics. Hearing loss, history of otitis media and pressure equalization (PE) tubes, communication mode, expressive/receptive language, and vocal quality were analyzed for all subjects and subjects grouped by age. Statistical methods included descriptive statistics and Pearson's chi-square tests of independence to test for differences between age groups for each variable of interest. Association analyses included Pearson's correlations.

RESULTS

Hearing and otological analyses revealed that 35% of subjects had hearing loss, 66% had a history of otitis media, and 62% had received PE tubes. Speech-language analyses revealed that 60% of subjects communicated using speech, 79% began speaking words at/after 24 months of age, 92% combined words at/after 36 months, and 41% used sign language before speech. There was a significant association between the age that first words were spoken and the age that PE tubes were first placed. Communication strengths noted in more than 40% of subjects included social interest, humor, and memory for people, past events, and/or facts.

CONCLUSIONS

Significant delays and impairment in speech-language were common, but the majority of those with SMS communicated using speech by age 6 years. Age was a significant factor for some aspects of hearing loss and communication. Neither hearing loss nor otitis media exacerbated language impairment. These results confirm and extend previous findings about the nature of speech, language, hearing, and otopathology in those with SMS.

Natural polyphenols for the management of autism spectrum disorder: a review of efficacy and molecular mechanisms

Natural polyphenols have been found to have some protective effects against neurodegenerative and neurodevelopmental disorders, which are attributed to a variety of biological properties, particularly antioxidant, immunomodulatory, and anti-inflammatory effects. Autism spectrum disorder is a complex neurological and neurodevelopmental disorder with no currently effective clinical treatment for its core symptoms. Regarding the management of autism spectrum disorder core symptoms, a number of experimental and clinical studies have been made using well-known dietary polyphenols with different effects and molecular mechanisms. The aim of this paper is to present the most effective natural polyphenols with the relevant molecular mechanisms in preclinical and clinical autism spectrum disorder studies.

Factors associated with blood mercury concentrations and their interactions with three glutathione S-transferase genes (GSTT1, GSTM1, and GSTP1): an exposure assessment study of typically developing Jamaican children

BACKGROUND

Jamaican soil is abundant in heavy metals including mercury (Hg). Due to availability and ease of access, fish is a traditional dietary component in Jamaica and a significant source of Hg exposure. Mercury is a xenobiotic and known neuro-toxicant that affects children's neurodevelopment. Human glutathione S-transferase (GST) genes, including GSTT1, GSTM1, and GSTP1, affect Hg conjugation and elimination mechanisms.

METHODS

In this exposure assessment study we used data from 375 typically developing (TD) 2-8-year-old Jamaican children to explore the association between environmental Hg exposure, GST genes, and their interaction effects on blood Hg concentrations (BHgCs). We used multivariable general linear models (GLMs).

RESULTS

We identified the child's age, consumption of saltwater fish, canned fish (sardine, mackerel), string beans, grain, and starches (pasta, macaroni, noodles) as the environmental factors significantly associated with BHgCs (all P < 0.05). A significant interaction between consumption of canned fish (sardine, mackerel) and GSTP1 in relation to BHgC using either a co-dominant or recessive genetic model (overall interaction P = 0.01 and P < 0.01, respectively) indicated that consumption of canned fish (sardine, mackerel) was significantly associated with higher mean BHgC only among children with the GSTP1 Ile105Val, Ile/Ile [Ratio of mean Hg (95% CI) = 1.59 (1.09, 2.32), P = 0.02] and Ile/Val [Ratio of mean Hg (95% CI) = 1.46 (1.12, 1.91), P = 0.01] genotypes.

CONCLUSIONS

Since this is the first study from Jamaica to report these findings, replication in other populations is recommended.

Heterogeneity of Autism Characteristics in Genetic Syndromes: Key Considerations for Assessment and Support

Purpose of Review

Elevated prevalence of autism characteristics is reported in genetic syndromes associated with intellectual disability. This review summarises recent evidence on the behavioural heterogeneity of autism in the following syndromes: Fragile X, Cornelia de Lange, Williams, Prader-Willi, Angelman, Down, Smith-Magenis, and tuberous sclerosis complex. Key considerations for assessment and support are discussed.

Recent Findings

The profile and developmental trajectory of autism-related behaviour in these syndromes indicate some degree of syndrome specificity which may interact with broader behavioural phenotypes (e.g. hypersociability), intellectual disability, and mental health (e.g. anxiety). Genetic subtype and co-occurring epilepsy within syndromes contribute to increased significance of autism characteristics. Autism-related strengths and challenges are likely to be overlooked or misunderstood using existing screening/diagnostic tools and criteria, which lack sensitivity and specificity within these populations.

Summary

Autism characteristics are highly heterogeneous across genetic syndromes and often distinguishable from non-syndromic autism. Autism diagnostic assessment practices in this population should be tailored to specific syndromes. Service provisions must begin to prioritise needs-led support.

Oxytocin protective effects on zebrafish larvae models of autism-like spectrum disorder

Objectives

Autism is a complicated neurodevelopmental disorder characterized by social interaction deficiencies, hyperactivity, anxiety, communication disorders, and a limited range of interests. The zebrafish (Danio rerio) is a social vertebrate used as a biomedical research model to understand social behavior mechanisms.

Materials and Methods

After spawning, the eggs were exposed to sodium valproate for 48 hr, after which the eggs were divided into eight groups. Except for the positive and control groups, there were six treatment groups based on oxytocin concentration (25, 50, and 100 μM) and time point (24 and 48 hr). Treatment was performed on days 6 and 7, examined by labeling oxytocin with fluorescein-5-isothiocyanate (FITC) and imaging with confocal microscopy and the expression levels of potential genes associated with the qPCR technique. Behavioral studies, including light-dark background preference test, shoaling behavior, mirror test, and social preference, were performed on 10, 11, 12, and 13 days post fertilization (dpf), respectively.

Results

The results showed that the most significant effect of oxytocin was at the concentration of 50 μM and the time point of 48 hr. Increased expression of shank3a, shank3b, and oxytocin receptor genes was also significant at this oxytocin concentration. Light-dark background preference results showed that oxytocin in the concentration of 50 µM significantly increased the number of crosses between dark and light areas compared with valproic acid (positive group). Also, oxytocin showed an increase in the frequency and time of contact between the two larvae. We showed a decrease in the distance in the larval group and an increase in time spent at a distance of one centimeter from the mirror.

Conclusion

Our findings showed that the increased gene expression of shank3a, shank3b, and oxytocin receptors improved autistic behavior. Based on this study some indications showed that oxytocin administration in the larval stage could significantly improve the autism-like spectrum.

Investigation of autism-related transcription factors underlying sex differences in the effects of bisphenol A on transcriptome profiles and synaptogenesis in the offspring hippocampus

BACKGROUND

Bisphenol A (BPA) has been linked to susceptibility to autism spectrum disorder (ASD). Our recent studies have shown that prenatal BPA exposure disrupted ASD-related gene expression in the hippocampus, neurological functions, and behaviors associated with ASD in a sex-specific pattern. However, the molecular mechanisms underlying the effects of BPA are still unclear.

METHODS

Transcriptome data mining and molecular docking analyses were performed to identify ASD-related transcription factors (TFs) and their target genes underlying the sex-specific effects of prenatal BPA exposure. Gene ontology analysis was conducted to predict biological functions associated with these genes. The expression levels of ASD-related TFs and targets in the hippocampus of rat pups prenatally exposed to BPA were measured using qRT-PCR analysis. The role of the androgen receptor (AR) in BPA-mediated regulation of ASD candidate genes was investigated using a human neuronal cell line stably transfected with AR-expression or control plasmid. Synaptogenesis, which is a function associated with genes transcriptionally regulated by ASD-related TFs, was assessed using primary hippocampal neurons isolated from male and female rat pups prenatally exposed to BPA.

RESULTS

We found that there was a sex difference in ASD-related TFs underlying the effects of prenatal BPA exposure on the transcriptome profiles of the offspring hippocampus. In addition to the known BPA targets AR and ESR1, BPA could directly interact with novel targets (i.e., KDM5B, SMAD4, and TCF7L2). The targets of these TFs were also associated with ASD. Prenatal BPA exposure disrupted the expression of ASD-related TFs and targets in the offspring hippocampus in a sex-dependent manner. Moreover, AR was involved in the BPA-mediated dysregulation of AUTS2, KMT2C, and SMARCC2. Prenatal BPA exposure altered synaptogenesis by increasing synaptic protein levels in males but not in females, but the number of excitatory synapses was increased in female primary neurons only.

CONCLUSIONS

Our findings suggest that AR and other ASD-related TFs are involved in sex differences in the effects of prenatal BPA exposure on transcriptome profiles and synaptogenesis in the offspring hippocampus. These TFs may play an essential role in an increased ASD susceptibility associated with endocrine-disrupting chemicals, particularly BPA, and the male bias of ASD.

Photobiomodulation Attenuated Cognitive Dysfunction and Neuroinflammation in a Prenatal Valproic Acid-Induced Autism Spectrum Disorder Mouse Model

Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by social communication and interaction disorders, as well as repetitive and restrictive behaviors. To date, no effective treatment strategies have been identified. However, photobiomodulation (PBM) is emerging as a promising treatment for neurological and neuropsychiatric disorders. We used mice exposed to valproic acid (VPA) as a model of ASD and found that pathological behavioral and histological changes that may have been induced by VPA were attenuated by PBM treatment. Pregnant mice that had been exposed to VPA were treated with PBM three times. Thereafter, we evaluated the offspring for developmental disorders, motor function, hyperactivity, repetitive behaviors, and cognitive impairment. PBM attenuated many of the pathological behaviors observed in the VPA-induced ASD mouse model. In addition, pathophysiological analyses confirmed that the increase in activated microglia and astrocytes observed in the VPA-induced ASD mouse model was attenuated by PBM treatment. This suggests that PBM can counteract the behavioral changes caused by neuroinflammation in ASD. Therefore, our data show that PBM has therapeutic potential and may reduce the prevalence of neurodevelopmental disorders such as ASD.

Head Movement Patterns during Face-to-Face Conversations Vary with Age

Advances in computational behavior analysis have the potential to increase our understanding of behavioral patterns and developmental trajectories in neurotypical individuals, as well as in individuals with mental health conditions marked by motor, social, and emotional difficulties. This study focuses on investigating how head movement patterns during face-to-face conversations vary with age from childhood through adulthood. We rely on computer vision techniques due to their suitability for analysis of social behaviors in naturalistic settings, since video data capture can be unobtrusively embedded within conversations between two social partners. The methods in this work include unsupervised learning for movement pattern clustering, and supervised classification and regression as a function of age. The results demonstrate that 3-minute video recordings of head movements during conversations show patterns that distinguish between participants that are younger vs. older than 12 years with 78% accuracy. Additionally, we extract relevant patterns of head movement upon which the age distinction was determined by our models.

Characteristics and treatment patterns of autism spectrum disorder in China, 2020

This study aimed to investigate the characteristics of children diagnosed with ASD in China and to estimate ASD treatment patterns in 2020. This study used data from the 2020 Survey on Family Circumstance and Demand Support and Resources among Autistic Children in China. The study sample included 4,557 children diagnosed with ASD aged 2-16 years old. Data were collected through questionnaires completed by parents. Of the 4,557 children with ASD, there was a male-to-female ratio of 5.75:1, and the average age when ASD risk symptoms were first reported was 27.97(SD=10.83) months. Higher proportions of families with highly educated parents (college and above; around 58%) and advanced parental age at childbirth (≥35 years; over 50%) were found among autistic children. Additionally, about 41.05% of autistic children had an immediate family member diagnosed with mental/intellectual disorders. In terms of the treatment patterns for autistic children, 84.82% had received behavioral and developmental treatments and 77.74% had received therapy-based treatments, whereas 3% children had not received any treatment. Higher odds of non-treatment were found among children who were male (OR=1.69, 95% CI: 1.01,3.03) and had ASD diagnosed later on (OR= 1.02, 95% CI:1.01,1.03), as compared to their counterparts. Future studies will need to explore the etiology of the disparities of ASD, and policy efforts are critically needed to understand and address the barriers for children with ASD to receive appropriate treatments.

Social Attention: Developmental Foundations and Relevance for Autism Spectrum Disorder

The use of the term "social attention" (SA) in the cognitive neuroscience and developmental psychopathology literature has increased exponentially in recent years, in part motivated by the aim to understand the early development of autism spectrum disorder (ASD). Unfortunately, theoretical discussions around the term have lagged behind its various uses. Here, we evaluate SA through a review of key candidate SA phenotypes emerging early in life, from newborn gaze cueing and preference for face-like configurations to later emerging skills such as joint attention. We argue that most of the considered SA phenotypes are unlikely to represent unique socioattentional processes and instead have to be understood in the broader context of bottom-up and emerging top-down (domain-general) attention. Some types of SA behaviors (e.g., initiation of joint attention) are linked to the early development of ASD, but this may reflect differences in social motivation rather than attention per se. Several SA candidates are not linked to ASD early in life, including the ones that may represent uniquely socioattentional processes (e.g., orienting to faces, predicting others' manual action goals). Although SA may be a useful superordinate category under which one can organize certain research questions, the widespread use of the term without proper definition is problematic. Characterizing gaze patterns and visual attention in social contexts in infants at elevated likelihood of ASD may facilitate early detection, but conceptual clarity regarding the underlying processes at play is needed to sharpen research questions and identify potential targets for early intervention.

Molecular Alterations of the Endocannabinoid System in Psychiatric Disorders

The therapeutic benefits of the current medications for patients with psychiatric disorders contrast with a great variety of adverse effects. The endocannabinoid system (ECS) components have gained high interest as potential new targets for treating psychiatry diseases because of their neuromodulator role, which is essential to understanding the regulation of many brain functions. This article reviewed the molecular alterations in ECS occurring in different psychiatric conditions. The methods used to identify alterations in the ECS were also described. We used a translational approach. The animal models reproducing some behavioral and/or neurochemical aspects of psychiatric disorders and the molecular alterations in clinical studies in post-mortem brain tissue or peripheral tissues were analyzed. This article reviewed the most relevant ECS changes in prevalent psychiatric diseases such as mood disorders, schizophrenia, autism, attentional deficit, eating disorders (ED), and addiction. The review concludes that clinical research studies are urgently needed for two different purposes: (1) To identify alterations of the ECS components potentially useful as new biomarkers relating to a specific disease or condition, and (2) to design new therapeutic targets based on the specific alterations found to improve the pharmacological treatment in psychiatry.

Latent profiles of autism symptoms in children and adolescents with Down syndrome

BACKGROUND

Down syndrome (DS) is associated with elevated rates of autism spectrum disorder (ASD) and autism symptomatology. To better characterise heterogeneity in ASD symptomatology in DS, profiles of caregiver-reported ASD symptoms were modelled for children and adolescents with DS.

METHODS

Participants (n = 125) were recruited through several multi-site research studies on cognition and language in DS. Using the Social Responsiveness Scale-2 (SRS-2; Constantino and Gruber 2012), two latent profile analyses (LPA) were performed, one on the broad composite scores of social communication and interaction and restricted interests and repetitive behaviour, and a second on the four social dimensions of social communication, social motivation, social awareness, and social cognition.

RESULTS

A three-profile model was the best fit for both analyses, with each analysis yielding a low ASD symptom profile, an elevated or mixed ASD symptom profile and a high ASD symptom profile. Associations were observed between profile probability scores and IQ, the number of co-occurring biomedical conditions reported, sex, and SRS-2 form.

CONCLUSIONS

Characterising heterogeneity in ASD symptom profiles can inform more personalised supports in this population, and implications for potential therapeutic approaches for individuals with DS are discussed.

Smith-Magenis Syndrome—Clinical Review, Biological Background and Related Disorders

Smith-Magenis syndrome (SMS) is a complex genetic disorder characterized by distinctive physical features, developmental delay, cognitive impairment, and a typical behavioral phenotype. SMS is caused by interstitial 17p11.2 deletions (90%), encompassing multiple genes and including the retinoic acid-induced 1 gene (RAI1), or by pathogenic variants in RAI1 itself (10%). RAI1 is a dosage-sensitive gene expressed in many tissues and acting as transcriptional regulator. The majority of individuals exhibit a mild-to-moderate range of intellectual disability. The behavioral phenotype includes significant sleep disturbance, stereotypes, maladaptive and self-injurious behaviors. In this review, we summarize current clinical knowledge and therapeutic approaches. We further discuss the common biological background shared with other conditions commonly retained in differential diagnosis.

An Overview of Zebrafish Modeling Methods in Drug Discovery and Development

Animal studies are recognized as a significant step forward in the bridging between drug discovery and clinical applications. Animal models, due to their relative genetic, molecular, physiological, and even anatomical similarities to humans, can provide a suitable platform for unraveling the mechanisms underlying human diseases and discovering new therapeutic approaches as well. Recently, zebrafish has attracted attention as a valuable experimental and pharmacological model in drug discovery and development studies due to its prominent characteristics such as the high degree of genetic similarity with humans, genetic manipulability, and prominent clinical features. Since advancing a theory to a valid and reliable observation requires the manipulation of animals, it is, therefore, essential to use efficient modeling methods appropriate to the different aspects of experimental conditions. In this context, applying several various approaches such as using chemicals, pathogens, and genetic manipulation approaches allows zebrafish development into a preferable model that mimics some human disease pathophysiology. Thus, such modeling approaches not only can provide a framework for a comprehensive understanding of the human disease mechanisms that have a counterpart in zebrafish but also can pave the way for discovering new drugs that are accompanied by higher amelioration effects on different human diseases.

Age-related changes in behavioural and emotional problems in Smith-Magenis syndrome measured with the Developmental Behavior Checklist

Smith-Magenis syndrome (SMS) is a genetic syndrome most often caused by a deletion on chromosome 17 or more rarely by a mutation in the retinoic acid-induced 1 gene. The aim of this study was to investigate the Developmental Behavior Checklist (DBC) profile of persons with SMS and the associations between behavioural and emotional problems, age, gender, adaptive behaviour and autism symptomatology. Twenty-eight persons with SMS were represented by their parents in this study. DBC Total scores are reduced with age, but they still show a mean that is clearly above the cut-off of 46. The differences between the age groups <9 years and 9-17 years (p = 0.024) and between the age groups <9 years and >18 years (p = 0.007) are significant. We found a significant decrease in behavioural and emotional problems with age in SMS. We did not find a relationship between adapted behaviour and communication and behavioural and emotional problems.

The emerging role of chromatin remodelers in neurodevelopmental disorders: a developmental perspective

Neurodevelopmental disorders (NDDs), including intellectual disability (ID) and autism spectrum disorders (ASD), are a large group of disorders in which early insults during brain development result in a wide and heterogeneous spectrum of clinical diagnoses. Mutations in genes coding for chromatin remodelers are overrepresented in NDD cohorts, pointing towards epigenetics as a convergent pathogenic pathway between these disorders. In this review we detail the role of NDD-associated chromatin remodelers during the developmental continuum of progenitor expansion, differentiation, cell-type specification, migration and maturation. We discuss how defects in chromatin remodelling during these early developmental time points compound over time and result in impaired brain circuit establishment. In particular, we focus on their role in the three largest cell populations: glutamatergic neurons, GABAergic neurons, and glia cells. An in-depth understanding of the spatiotemporal role of chromatin remodelers during neurodevelopment can contribute to the identification of molecular targets for treatment strategies.

Alteration of the steroidogenesis in boys with autism spectrum disorders

The etiology of autism spectrum disorders (ASD) remains unknown, but associations between prenatal hormonal changes and ASD risk were found. The consequences of these changes on the steroidogenesis during a postnatal development are not yet well known. The aim of this study was to analyze the steroid metabolic pathway in prepubertal ASD and neurotypical boys. Plasma samples were collected from 62 prepubertal ASD boys and 24 age and sex-matched controls (CTRL). Eighty-two biomarkers of steroidogenesis were detected using gas-chromatography tandem-mass spectrometry. We observed changes across the whole alternative backdoor pathway of androgens synthesis toward lower level in ASD group. Our data indicate suppressed production of pregnenolone sulfate at augmented activities of CYP17A1 and SULT2A1 and reduced HSD3B2 activity in ASD group which is partly consistent with the results reported in older children, in whom the adrenal zona reticularis significantly influences the steroid levels. Furthermore, we detected the suppressed activity of CYP7B1 enzyme readily metabolizing the precursors of sex hormones on one hand but increased anti-glucocorticoid effect of 7α-hydroxy-DHEA via competition with cortisone for HSD11B1 on the other. The multivariate model found significant correlations between behavioral indices and circulating steroids. From dependent variables, the best correlation was found for the social interaction (28.5%). Observed changes give a space for their utilization as biomarkers while reveal the etiopathogenesis of ASD. The aforementioned data indicate a direction of the future research with a focus on the expression and functioning of genes associated with important steroidogenic enzymes in ASD patients from early childhood to adrenarche.

Brain-Enriched Coding and Long Non-coding RNA Genes Are Overrepresented in Recurrent Neurodevelopmental Disorder CNVs

Autism spectrum disorder (ASD) is a neurodevelopmental condition with substantial phenotypic and etiological heterogeneity. Although 10%-20% of ASD cases are attributable to copy number variation (CNV), causative genomic loci and constituent genes remain unclarified. We have developed SNATCNV, a tool that outperforms existing tools, to identify 47 recurrent ASD CNV regions from 19,663 cases and 6,479 controls documented in the AutDB database. Analysis of ASD CNV gene content using FANTOM5 shows that constituent coding genes and long non-coding RNAs have brain-enriched patterns of expression. Notably, such enrichment is not observed for regions identified by using other tools. We also find evidence of sexual dimorphism, one locus uniquely comprising a single lncRNA gene, and correlation of CNVs to distinct clinical and behavioral traits. Finally, we analyze a large dataset for schizophrenia to further demonstrate that SNATCNV is an effective, publicly available tool to define genomic loci and causative genes for multiple CNV-associated conditions.

Cortical signatures in behaviorally clustered autistic traits subgroups: a population-based study

Extensive heterogeneity in autism spectrum disorder (ASD) has hindered the characterization of consistent biomarkers, which has led to widespread negative results. Isolating homogenized subtypes could provide insight into underlying biological mechanisms and an overall better understanding of ASD. A total of 1093 participants from the population-based "Healthy Brain Network" cohort (Child Mind Institute in the New York City area, USA) were selected based on score availability in behaviors relevant to ASD, aged 6-18 and IQ >= 70. All participants underwent an unsupervised clustering analysis on behavioral dimensions to reveal subgroups with ASD traits, identified by the presence of social deficits. Analysis revealed three socially impaired ASD traits subgroups: (1) high in emotionally dysfunctional traits, (2) high in ADHD-like traits, and (3) high in anxiety and depressive symptoms. 527 subjects had good quality structural MRI T1 data. Site effects on cortical features were adjusted using the ComBat method. Neuroimaging analyses compared cortical thickness, gyrification, and surface area, and were controlled for age, gender, and IQ, and corrected for multiple comparisons. Structural neuroimaging analyses contrasting one combined heterogeneous ASD traits group against controls did not yield any significant differences. Unique cortical signatures, however, were observed within each of the three individual ASD traits subgroups versus controls. These observations provide evidence of ASD traits subtypes, and confirm the necessity of applying dimensional approaches to extract meaningful differences, thus reducing heterogeneity and paving the way to better understanding ASD traits.

Parental experiences with behavioural problems in Smith-Magenis syndrome: The need for syndrome-specific competence

The experience of having a rare disorder was summarised in a large study as 'falling outside the vast field of knowledge of the professionals'. Parents (31 mothers and 17 fathers) of 32 persons with Smith-Magenis syndrome (SMS) participated in this study. A phenomenological approach was used to analyse the data into topics and themes. Four themes emerged: behavioural challenges displayed, parents' strategies for meeting the challenging behaviours, parents' experiences of their own competence and parents' experiences of professionals' competence and understanding regarding children with SMS and their behaviour challenges. We found that parents of children with SMS experience that they are exposed to severe challenging behaviours from their child. The parents believe that they experience more misunderstandings with professionals and that the challenging behaviours increase because there are some specific characteristics of SMS that professionals are not aware of or do not consider in their support services.

Neuropsychiatric phenotypes and a distinct constellation of ASD features in 3q29 deletion syndrome: results from the 3q29 registry

Background

The 1.6 Mb 3q29 deletion is associated with neurodevelopmental and psychiatric phenotypes, including increased risk for autism spectrum disorder (ASD) and a 20 to 40-fold increased risk for schizophrenia. However, the phenotypic spectrum of the deletion, particularly with respect to ASD, remains poorly described.

Methods

We ascertained individuals with 3q29 deletion syndrome (3q29Del, “cases,” n = 93, 58.1% male) and typically developing controls (n = 64, 51.6% male) through the 3q29 registry (https://3q29deletion.patientcrossroads.org). Self-report of neuropsychiatric illness was evaluated for 93 cases. Subsets of participants were evaluated with the Social Responsiveness Scale (SRS, n = 48 cases, 56 controls), Social Communication Questionnaire (n = 33 cases, 46 controls), Autism Spectrum Screening Questionnaire (n = 24 cases, 35 controls), and Achenbach Behavior Checklists (n = 48 cases, 57 controls).

Results

3q29Del cases report a higher prevalence of autism diagnoses versus the general population (29.0% vs. 1.47%, p < 2.2E− 16). Notably, 3q29 deletion confers a greater influence on risk for ASD in females (OR = 41.8, p = 4.78E− 05) than in males (OR = 24.6, p = 6.06E− 09); this is aligned with the reduced male:female bias from 4:1 in the general population to 2:1 in our study sample. Although 71% of cases do not report a diagnosis of ASD, there is evidence of significant social disability (3q29Del SRS T-score = 71.8, control SRS T-score = 45.9, p = 2.16E− 13). Cases also report increased frequency of generalized anxiety disorder compared to controls (28.0% vs. 6.2%, p = 0.001), which is mirrored by elevated mean scores on the Achenbach diagnostic and statistical manual-oriented sub-scales (p < 0.001). Finally, cases show a distinct constellation of ASD features on the SRS as compared to idiopathic ASD, with substantially elevated Restricted Interests and Repetitive Behaviors, but only mild impairment in Social Motivation.

Conclusions

Our sample of 3q29Del is significantly enriched for ASD diagnosis, especially among females, and features of autism may be present even when an ASD diagnosis is not reported. Further, the constellation of ASD features in this population is distinct from idiopathic ASD, with substantially less impaired social motivation. Our study implies that ASD evaluation should be the standard of care for individuals with 3q29Del. From a research perspective, the distinct ASD subtype present in 3q29Del is an ideal entry point for expanding understanding of ASD.

Electronic supplementary material

The online version of this article (10.1186/s13229-019-0281-5) contains supplementary material, which is available to authorized users.

Autism-related behaviors in the cyclooxygenase-2-deficient mouse model

Prostaglandin E2 (PGE2) is an endogenous lipid molecule involved in normal brain development. Cyclooxygenase-2 (COX2) is the main regulator of PGE2 synthesis. Emerging clinical and molecular research provides compelling evidence that abnormal COX2/PGE2 signaling is associated with autism spectrum disorder (ASD). We previously found that COX2 knockout mice had dysregulated expression of many ASD genes belonging to important biological pathways for neurodevelopment. The present study is the first to show the connection between irregular COX2/PGE2 signaling and autism-related behaviors in male and female COX2-deficient knockin, (COX)-2^- , mice at young (4-6 weeks) or adult (8-11 weeks) ages. Autism-related behaviors were prominent in male (COX)-2^- mice for most behavioral tests. In the open field test, (COX)-2^- mice traveled more than controls and adult male (COX)-2^- mice spent less time in the center indicating elevated hyperactive and anxiety-linked behaviors. (COX)-2^- mice also buried more marbles, with males burying more than females, suggesting increased anxiety and repetitive behaviors. Young male (COX)-2^- mice fell more frequently in the inverted screen test revealing motor deficits. The three-chamber sociability test found that adult female (COX)-2^- mice spent less time in the novel mouse chamber indicative of social abnormalities. In addition, male (COX)-2^- mice showed altered expression of several autism-linked genes: Wnt2, Glo1, Grm5 and Mmp9. Overall, our findings offer new insight into the involvement of disrupted COX2/PGE2 signaling in ASD pathology with age-related differences and greater impact on males. We propose that (COX)-2^- mice might serve as a novel model system to study specific types of autism.