Genetics of autistic disorders: review and clinical implications

Evaluative contexts facilitate implicit mentalizing: relation to the broader autism phenotype and mental health

One promising account for autism is implicit mentalizing difficulties. However, this account and even the existence of implicit mentalizing have been challenged because the replication results are mixed. Those unsuccessful replications may be due to the task contexts not being sufficiently evaluative. Therefore, the current study developed a more evaluative paradigm by implementing a prompt question. This was assessed in 60 non-autistic adults and compared with a non-prompt version. Additionally, parents of autistic children are thought to show a genetic liability to autistic traits and cognition and often report mental health problems, but the broader autism phenotype (BAP) is an under-researched area. Thus, we also aimed to compare 33 BAP and 26 non-BAP mothers on mentalizing abilities, autistic traits, compensation and mental health. Our results revealed that more evaluative contexts can facilitate implicit mentalizing in BAP and non-BAP populations, and thus improve task reliability and replicability. Surprisingly, BAP mothers showed better implicit mentalizing but worse mental health than non-BAP mothers, which indicates the heterogeneity in the broader autism phenotype and the need to promote BAP mothers' psychological resilience. The findings underscore the importance of contexts for implicit mentalizing and the need to profile mentalizing and mental health in BAP parents.

Translating neuroimaging changes to neuro-endophenotypes of autistic spectrum disorder: a narrative review

Background

Autism-spectrum disorder is a neurodevelopmental disorder with heterogeneity in etiopathogenesis and clinical presentation. Neuroanatomical and neurophysiological abnormalities may represent neural endophenotypes for autism spectrum disorders which may help identify subgroups of patients seemingly similar in clinical presentation yet different in their pathophysiological underpinnings. Furthermore, a thorough understanding of the pathophysiology of disease can pave the way to effective treatments, prevention, and prognostic predictions. The aim of this review is to identify the predominant neural endophenotypes in autism-spectrum disorder. The evidence was researched at the following electronic databases: Pubmed, PsycINFO, Scopus, Web of Science, and EMBASE.

Results

Enlarged brain, especially frontotemporal cortices have been consistently reported by structural neuroimaging, whereas functional neuroimaging has revealed frontotemporal dysconnectivity.

Conclusions

Regrettably, many of these findings have not been consistent. Therefore, translating these findings into neural endophenotype is by far an attempt in its budding stage. The structural and functional neuroimaging changes may represent neural endophenotypes unique to autism-spectrum disorder. Despite inconsistent results, a clinically meaningful finding may require combined efforts of autism-spectrum-disorder researchers focused on different aspects of basic, genetic, neuroimaging, and clinical research.

Integration of Transcriptome and Exome Genotyping Identifies Significant Variants with Autism Spectrum Disorder

Autism is a complex disease with genetic predisposition factors. Real factors for treatment and early diagnosis are yet to be defined. This study integrated transcriptome and exome genotyping for identifying functional variants associated with autism spectrum disorder and their impact on gene expression to find significant variations. More than 1800 patients were screened, and 70 (47 male/23 female) with an average age of 7.56 ± 3.68 years fulfilled the DSM-5 criteria for autism. Analysis revealed 682 SNPs of 589 genes significantly (p < 0.001) associated with autism among the putative functional exonic variants (n = 243,345) studied. Olfactory receptor genes on chromosome 6 were significant after Bonferroni correction (α = 0.05/243345 = 2.05 × 10−7) with a high degree of linkage disequilibrium on 6p22.1 (p = 6.71 × 10−9). The differentially expressed gene analysis of autistic patients compared to controls in whole RNA sequencing identified significantly upregulated (foldchange ≥ 0.8 and p-value ≤ 0.05; n = 125) and downregulated (foldchange ≤ −0.8 and p-value ≤ 0.05; n = 117) genes. The integration of significantly up- and downregulated genes and genes of significant SNPs identified regulatory variants (rs6657480, rs3130780, and rs1940475) associated with the up- (ITGB3BP) and downregulation (DDR1 and MMP8) of genes in autism spectrum disorder in people of Arab ancestries. The significant variants could be a biomarker of interest for identifying early autism among Arabs and helping to characterize the genes involved in the susceptibility mechanisms for autistic subjects.

A rapid realist review of patient engagement in patient-oriented research and health care system impacts: part one

BACKGROUND

Patient-oriented research affords individuals with opportunities to genuinely contribute to health care research as members of research teams. While checklists and frameworks can support academic researchers' awareness of patient engagement methods, less guidance appears available to support their understanding of how to develop and maintain collaborative relationships with their patient partners. This knowledge is essential as patient partners report that the social atmospheres of research teams significantly impacts the quality of their experiences. This study sought to develop theory regarding how academic researchers support and sustain patient engagement in patient-oriented research.

METHODS

A six-step, rapid realist review was conducted: (1) research question development, (2) preliminary theory development, (3) search strategy development; (4) study selection and appraisal, (4) data extraction, analysis and synthesis (5) identification of relevant formal theories, and (6) theory refinement with stakeholders. Findings were additionally distilled by collective competence theory.

RESULTS

A program theory was developed from 62 international studies which illuminated mechanisms supporting academic researchers to engage patient partners, contexts supporting these mechanisms, and resources that enabled mechanism activation. Interaction between seven contexts (patient-oriented research belief, prior interaction with a healthcare system, prior interaction with a particular academic researcher, educational background of patient partner, prior experience with patient-oriented research, study type, and time lived in a rural-urban setting) and seven mechanisms (deciding to become involved in patient-oriented research, recognizing valuable experiential knowledge, cultural competence, reducing power differentials, respectful team environment, supporting patient partners to feel valued, and readiness to research) resulted in an intermediate outcome (sense of trust). Trust then acted as an eighth mechanism which triggered the final-level outcome (empowered patient-centred lens).

CONCLUSIONS

Our theory posits that if patient partners trust they are a member of a supportive team working alongside academic researchers who authentically want to incorporate their input, then they are empowered to draw upon their experiential knowledge of health care systems and contribute as researchers in patient-oriented research. Our theory extends conceptual thinking regarding the importance of trust on patient-oriented research teams, how patient partners' trust is shaped by team interactions, and the role that academic researchers have within those interactions.

Prevalence and risk factors of autism spectrum disorders in preschool children in Sharkia, Egypt: a community-based study

Background

Lateness in the diagnosis of autism spectrum disorders (ASD) results in significant disability and pressure on affected children and their families. We aimed to detect the preschool children who have high-risk criteria for ASD in Sharkia Governorate in Egypt and assess the prevalence and risk factors of ASD. A cross-sectional community-based study was done in 39 kindergartens throughout Sharkia Governorate, Egypt, using a multi-stage random sampling technique. The study included two phases, the screening phase, where 3722 preschool children were screened by Modified Check List for Toddlers/Revised (M-CHAT-R), and the diagnostic phase where the diagnosis of ASD among the high-risk children was made according to the research diagnostic criteria of Diagnostic and Statistical Manual of Mental Disorders 5th edition (DSM-5) of ASD administrated by experienced psychiatrists and the Childhood Autism Rating Scale (CARS).

Results

This study showed that 2.8% of children were at high risk for ASD. The prevalence of ASD in Sharkia Governorate was 5.4/1000. The significant risk factors for the disorder were the presence of factories near the house, first and middle child order, congenital anomalies, child medication during the first year of life, child chronic medical condition, child attachment to TV, a medical condition affecting mother during pregnancy, and psychiatric disorders history in the family.

Conclusion

Autism spectrum disorder is prevalent in preschool children in Sharkia, Egypt, and multiple risk factors contribute to this prevalence.

[Genetic risk factors and their influence on neural development in autism spectrum disorders]

Genetic risk factors and their influence on neural development in autism spectrum disorders Abstract. Abstract. Autism spectrum disorders are etiologically based on genetic and specific gene x biologically relevant environmental risk factors. They are diagnosed based on behavioral characteristics, such as impaired social communication and stereotyped, repetitive behavior and sensory as well as special interests. The genetic background is heterogeneous, i. e., it comprises diverse genetic risk factors across the disorder and high interindividual differences of specific genetic risk factors. Nevertheless, risk factors converge regarding underlying biological mechanisms and shared pathways, which likely cause the autism-specific behavioral characteristics. The current selective literature review summarizes differential genetic risk factors and focuses particularly on mechanisms and pathways currently being discussed by international research. In conclusion, clinically relevant aspects and open translational research questions are presented.

Genetic risk factors for autism-spectrum disorders: a systematic review based on systematic reviews and meta-analysis

BACKGROUND

Based on recent evidence, more than 200 susceptibility genes have been identified to be associated with autism until now. Correspondingly, cytogenetic abnormalities have been reported for almost every chromosome. While the results of multiple genes associated with risk factors for autism are still incomplete, this paper systematically reviews published meta-analyses and systematic reviews of evidence related to autism occurrence.

METHOD

Literature search was conducted in the PubMed system, and the publication dates were limited between January 2000 and July 2020. We included a meta-analysis and systematic review that assessed the impact of related gene variants on the development of autism. After screening, this comprehensive literature search identified 31 meta-analyses and ten systematic reviews. We arranged the genes related to autism in the published studies according to the order of the chromosomes, and based on the results of a meta-analysis and systematic review, we selected 6 candidate genes related to ASD, namely MTHFR C677T, SLC25A12, OXTR, RELN, 5-HTTLPR, SHANK, including basic features and functions. In addition to these typical genes, we have also listed candidate genes that may exist on almost every chromosome that are related to autism.

RESULTS

We found that the results of several literature reviews included in this study showed that the MTHFR C667T variant was a risk factor for the occurrence of ASD, and the results were consistent. The results of studies on SLC25A12 variation (rs2056202 and rs2292813) and ASD risk were inconsistent but statistically significant. No association of 5-HTTLPR was found with autism, but when subgroup analysis was performed according to ethnicity, the association was statistically significant. RELN variants (rs362691 and rs736707) were consistent with ASD risk studies, but some of the results were not statistically significant.

CONCLUSION

This review summarized the well-known ASD candidate genes and listed some new genes that need further study in larger sample sets to improve our understanding of the genetic basis of ASD, but sample size and heterogeneity remain major limiting factors in some genome-wide association studies. We also found that common genetic variants in some genes may be co-risk factors for autism or other neuropsychiatric disorders when we collated these results. It is worth considering screening for these mutations in clinical applications.

A mini-review: Bridging the gap between autism spectrum disorder and pain comorbidities

Background

Pain is a complex neurobiological response with a multitude of causes; however, patients with autism spectrum disorder (ASD) often report chronic pain with no known etiology. Recent research has been aimed toward identifying the causal mechanisms of pain in mouse and human models of ASD. In recent years, efforts have been made to better document and explore secondary phenotypes observed in ASD patients in the clinic. As new sequencing studies have become more powered with larger cohorts within ASD, specific genes and their variants are often left uncharacterized or validated. In this review we highlight ASD risk genes often presented with pain comorbidities.

Aims

This mini-review bridges the gap between two fields of literature, neurodevelopmental disorders and pain research. We discuss the importance of the genetic landscape of ASD and its links to pain phenotypes.

Results

Among the numerous genes implicated in ASD, few have been implicated with varying severities of pain comorbidity. Mutations in these genes, such as SCN9A, SHANK3, and CNTNAP2, lead to altered neuronal function that produce different responses to pain, shown in both mouse and human models.

Conclusion

There is a necessity to use new technologies to advance the current understanding of ASD risk genes and their contributions to pain. Secondly, there is a need to power future ASD risk genes associated with pain with their own cohort, because a better understanding is needed of this subpopulation.

Maternal excessive gestational weight gain as a risk factor for autism spectrum disorder in offspring: a systematic review

Background

Abnormal gestational weight gain (GWG) is a prenatal complication that may contribute to long-term behavioral and neurodevelopmental differences in offspring. This systematic review summarizes research on the association between maternal GWG and risk of autism spectrum disorder (ASD) in offspring.

Methods

Google and electronic databases, including PubMed, SCOPUS, Embase, Cochrane Library and Google Scholar, were searched for original human studies published in English through June 2020. Articles that examined the association between GWG and risk of ASD in offspring were included. Duplicate and irrelevant studies were removed; and data were obtained through critical analysis.

Results

Of 96 articles searched, eight studies were included in the final review. All studies (n = 7) investigating the association of maternal excessive GWG with risk of ASD in offspring indicated that high GWG was independently associated with an increased risk of ASD. Of five studies investigating the association of inadequate GWG with the risk of ASD, four indicated that low GWG was not associated with an increased risk of ASD. Of seven studies examining the association of maternal pre-pregnancy BMI or weight with the risk of ASD, five reported that maternal pre-pregnancy BMI or weight did not appear to be independently associated with risk of ASD. The GWG-ASD association is independent of maternal BMI and child’s intellectual disability, but offspring’s genetic susceptibility connection to the GWG-ASD association remains a topic of debate.

Conclusions

The findings suggest that maternal excessive GWG may be associated with increased risk of ASD in offspring. However, insufficient GWG does not appear to have such association.

The association between newborn screening analytes as measured on a second screen and childhood autism in a Texas Medicaid population

Autism (or autism spectrum disorder [ASD]) is an often disabling childhood neurologic condition of mostly unknown cause. We previously explored whether there was an association of ASD with any analyte measured in the first newborn screening blood test. Here we explore the second screen. Our matched case-control study examined data on 3-5 year-old patients with any ASD diagnosis in the Texas Medicaid system in 2010-2012. Subjects were linked to their 2007-2009 newborn screening blood test data, which included values for 36 analytes or analyte ratios. Data were available for 3,005 cases and 6,212 controls. The most compelling associations were evident for fatty acid oxidation analytes octanoylcarnitine (C8) and octanoylcarnitine/acetylcarnitine (C8/C2). Their adjusted odds ratios comparing 10th versus first analyte deciles were between 1.42 and 1.54 in total births, term births, and males. C8 was consistent with first screen results. Adipylcarnitine (C6DC), an organic acid analyte, showed opposite results in the two screens. Several other analytes exhibiting significant associations in the first screen did not in the second. Our results provide evidence that abnormal newborn blood levels of some carnitines may be associated with risk of later ASD, possibly related to their involvement with mitochondrial function in the developing brain.

Nutritional Status and Symptoms in Preschool Children With Autism Spectrum Disorder: A Two-Center Comparative Study in Chongqing and Hainan Province, China

Objective: The study aimed to compare the nutritional status and symptoms of preschool children with autism spectrum disorder (ASD) from two regions of China, and to analyze the association between nutritional status and symptoms of ASD. Methods: In this cross-sectional study, 738 ASD children and 302 typically developing children (TD) were recruited from Chongqing and Hainan of China. Symptoms of ASD children were evaluated with the Autism Behavior Checklist (ABC), Social Responsiveness Scale (SRS), and Childhood Autism Rating Scale (CARS). Neurodevelopment of ASD children was assessed with the Gesell Developmental Scale (GDS). Nutritional status was evaluated by anthropometric measures, biochemical detection of micronutrients, and providing questionnaire and food frequency questionnaire (FFQ) to caregivers. Results: Comparing ASD children with local TD children, ASD children consumed fewer whole grains, milk and dairy products, beans and soy products, vegetables, and fruits than local TD children in both regions. The serum concentrations of folate, vitamin B12 (VB12), and vitamin D (VD) were consistently lower in ASD children in both regions. Comparing the ASD children between the two regions, the ASD children in Chongqing had significantly higher mean scores of CARS, SRS, and ABC than those in Hainan. The ASD children in Chongqing consumed fewer whole grains, seafood, and fruits than those in Hainan. The serum concentrations of ferritin, vitamin A (VA), VB12, and VD were reduced in the ASD children of Chongqing than those in Hainan, and the ASD children in Chongqing had higher deficiency rates of zinc, ferritin, VA, and VD than those in Hainan. The serum levels of VA, VD, and folate showed a negative association with symptom scores of ASD children. VD and zinc levels had a positive association with the GDS scores of ASD children. Conclusions: ASD children exhibit a higher risk of nutrient deficiencies than neurotypical children, and there are regional differences in the nutritional status of ASD children. Micronutrients VA, VD, folate, and zinc levels were correlated with symptoms and development of ASD children. Therefore, it is essential to provide detailed nutrition evaluation and individualized nutrition interventions for ASD children from different backgrounds.

Dietary Approaches to the Management of Autism Spectrum Disorders

This chapter reviews the literature surrounding autism spectrum disorders (ASD) and their relation to gastrointestinal (GI), behavioral, neurological, and immunological functioning. Individuals with ASD often have poor GI health, including bowel motility issues, autoimmune and/or other adverse responses to certain foods, and lack of necessary nutrient absorption. These issues may be caused or exacerbated by restrictive behavioral patterns (e.g., preference for sweet and salty foods and/or refusal of healthy foods). Those individuals with GI issues tend to demonstrate more behavioral deficits (e.g., irritability, agitation, hyperactivity) and also tend to have an imbalance in overall gut microbiome composition, thus corroborating several studies that have implicated brain-gut pathways as potential mediators of behavioral dysfunction.We examine the literature regarding dietary approaches to managing ASDs, including elimination diets for gluten, casein, or complex carbohydrates, a ketogenic diet, and a low oxalate diet. We also explore the research examining dietary supplements such as fatty acids, pro- and prebiotics, vitamins, minerals, glutathione, phytochemicals, and hormones. The research on dietary approaches to managing ASDs is limited and the results are mixed. However, a few approaches, such as the gluten-free/casein-free diet, fatty acid supplementation, and pre/probiotics have generally demonstrated improved GI and associated behavioral symptoms. Given that GI issues seem to be overrepresented in ASD populations, and that GI issues have been associated with a number behavioral and neurological deficits, dietary manipulation may offer a cheap and easily implemented approach to improve the lives of those with ASD.

High-resolution chromosomal microarray analysis for copy-number variations in high-functioning autism reveals large aberration typical for intellectual disability

Copy-number variants (CNVs), in particular rare, small and large ones (< 1% frequency) and those encompassing brain-related genes, have been shown to be associated with neurodevelopmental disorders like autism spectrum disorders (ASDs), attention deficit hyperactivity disorder (ADHD), and intellectual disability (ID). However, the vast majority of CNV findings lack specificity with respect to autistic or developmental-delay phenotypes. Therefore, the aim of the study was to investigate the size and frequency of CNVs in high-functioning ASD (HFA) without ID compared with a random population sample and with published findings in ASD and ID. To investigate the role of CNVs for the "core symptoms" of high-functioning autism, we included in the present exploratory study only patients with HFA without ID. The aim was to test whether HFA have similar large rare (> 1 Mb) CNVs as reported in ASD and ID. We performed high-resolution chromosomal microarray analysis in 108 children and adolescents with HFA without ID. There was no significant difference in the overall number of rare CNVs compared to 124 random population samples. However, patients with HFA carried significantly more frequently CNVs containing brain-related genes. Surprisingly, six HFA patients carried very large CNVs known to be typically present in ID. Our findings provide new evidence that not only small, but also large CNVs affecting several key genes contribute to the genetic etiology/risk of HFA without affecting their intellectual ability.

Co-Occurrence of ASD and ADHD Traits in an Adult Population

Objective: ADHD and autism spectrum disorder (ASD) can be viewed as the extreme end of traits found in the general population. Clinical and genetic studies suggest that ADHD and ASD often co-occur and share genetic susceptibility. The aim of this study was to examine co-occurrence of ADHD and ASD traits in the general population. Method: In total, 334 participants were recruited from a population-based sample. Four questionnaires assessing current and retrospective ADHD and ASD traits were administered online: the Adult ADHD Self-Report Scale (ASRS) Symptom Checklist, the Wender Utah Rating Scale (WURS-25), the Broad Autism Phenotype Questionnaire (BAPQ), and the Autism Spectrum Quotient (AQ). Results: A significant correlation was found between ADHD and autistic traits. In particular, higher inattention and overall ADHD scores were associated with self-reported deficits in communication and social skills. Conclusion: Our findings are similar to results from studies on clinical populations, suggesting that ADHD and ASD might share common etiology.

The association between newborn screening analytes and childhood autism in a Texas Medicaid population, 2010-2012

Autism (or autism spectrum disorder [ASD]) is an often disabling childhood neurologic condition of mostly unknown cause. It is commonly diagnosed at 3 or 4 years of age. We explored whether there was an association of any analytes measured by newborn screening tests with a later diagnosis of ASD. A database was compiled of 3-5 year-old patients with any ASD diagnosis in the Texas Medicaid system in 2010-2012. Two controls (without any ASD diagnosis) were matched to each case by infant sex and birth year/month. All study subjects were linked to their 2007-2009 birth and newborn screening laboratory records, including values for 36 analytes or analyte ratios. We examined the association of analytes/ratios with a later diagnosis of ASD. Among 3,258 cases and 6,838 controls, seven analytes (e.g., 17-hydroxyprogesterone, acylcarnitines) were associated with a later ASD diagnosis. In this exploratory study, an ASD diagnosis was associated with 7 of 36 newborn screening analytes/ratios. These findings should be replicated in other population-based datasets.

Uncovering the Functional Link Between SHANK3 Deletions and Deficiency in Neurodevelopment Using iPSC-Derived Human Neurons

SHANK3 mutations, including de novo deletions, have been associated with autism spectrum disorders (ASD). However, the effects of SHANK3 loss of function on neurodevelopment remain poorly understood. Here we generated human induced pluripotent stem cells (iPSC) in vitro, followed by neuro-differentiation and lentivirus-mediated shRNA expression to evaluate how SHANK3 knockdown affects the in vitro neurodevelopmental process at multiple time points (up to 4 weeks). We found that SHANK3 knockdown impaired both early stage of neuronal development and mature neuronal function, as demonstrated by a reduction in neuronal soma size, growth cone area, neurite length and branch numbers. Notably, electrophysiology analyses showed defects in excitatory and inhibitory synaptic transmission. Furthermore, transcriptome analyses revealed that multiple biological pathways related to neuron projection, motility and regulation of neurogenesis were disrupted in cells with SHANK3 knockdown. In conclusion, utilizing a human iPSC-based neural induction model, this study presented combined morphological, electrophysiological and transcription evidence that support that SHANK3 as an intrinsic, cell autonomous factor that controls cellular function development in human neurons.

Helminth therapy for autism under gut-brain axis- hypothesis

Autism is a neurodevelopmental disease included within Autism Syndrome Disorder (ASD) spectrum. ASD has been linked to a series of genes that play a role in immune response function and patients with autism, commonly suffer from immune-related comorbidities. Despite the complex pathophysiology of autism, Gut-brain axis is gaining strength in the understanding of several neurological disorders. In addition, recent publications have shown the correlation between immune dysfunctions, gut microbiota and brain with the behavioral alterations and comorbid symptoms found in autism. Gut-brain axis acts as the "second brain", in a communication network established between neural, endocrine and the immunological systems. On the other hand, Hygiene Hypothesis suggests that the increase in the incidence of autoimmune diseases in the modern world can be attributed to the decrease of exposure to infectious agents, as parasitic nematodes. Helminths induce modulatory and protective effects against several inflammatory disorders, maintaining gastrointestinal homeostasis and modulating brain functions. Helminthic therapy has been previously performed in diseases such as ulcerative colitis, Crohn's disease, diabetes, multiple sclerosis, asthma, rheumatoid arthritis, and food allergies. Considering gut-brain axis, Hygiene Hypothesis, and the modulatory effects of helminths I hypothesized that a treatment with Trichuris suis soluble products represents a feasible holistic treatment for autism, and the key for the development of novel treatments. Preclinical studies are required to test this hypothesis.

Communicating complex genomic information: A counselling approach derived from research experience with Autism Spectrum Disorder

Individuals with Autism Spectrum Disorder (ASD) share characteristics (impairments in socialization and communication, and repetitive interests and behaviour), but differ in their developmental course, pattern of symptoms, and cognitive and language abilities. The development of standardized phenotyping has revealed ASD to clinically be vastly heterogeneous, ranging from milder presentations to more severe forms associated with profound intellectual disability. Some 100 genes have now been implicated in the etiology of ASD, and advances in genome-wide testing continue to yield new data at an unprecedented rate. As the translation of this data is incorporated into clinical care, genetic professionals/counsellors, as well as other health care providers, will benefit from guidelines and tools to effectively communicate such genomic information. Here, we present a model to facilitate communication regarding the complexities of ASD, where clinical and genetic heterogeneity, as well as overlapping neurological conditions are inherent. We outline an approach for counselling families about their genomic results grounded in our direct experience from counselling families participating in an ASD research study, and supported by rationale from the literature.

Autism spectrum disorder and schizophrenia: boundaries and uncertainties

Autism and schizophrenia were placed in different diagnostic categories in DSM-III, having previously been considered as related diagnostic entities. New evidence suggests that these disorders show clinical and cognitive deficit overlaps and shared neurobiological characteristics. Furthermore, children presenting with both autism spectrum disorder (ASD) and psychotic experiences may represent a subgroup of ASD more closely linked to psychosis. The study of ASD and childhood schizophrenia, and their clinical boundaries and overlapping pathophysiological characteristics, may clarify their relationship and lead to more effective interventions. This article discusses the relationship through a critical review of current and historical dilemmas surrounding the phenomenology and pathophysiology of these disorders. It provides a framework for working with children and young people with mixed clinical presentations, illustrated by three brief fictional case vignettes.

Common functional variants of the glutamatergic system in Autism spectrum disorder with high and low intellectual abilities

The genetic architecture underlying Autism spectrum disorder (ASD) has been suggested to differ between individuals with lower (IQ ≤ 70; LIQ) and higher intellectual abilities (IQ > 70; HIQ). Among the identified pathomechanisms, the glutamatergic signalling pathway is of specific interest in ASD. We investigated 187 common functional variants of this neurotransmitter system for association with ASD and with symptom severity in two independent samples, a German (German-ALL: N = 583 families) and the Autism Genome Project cohort (AGP-ALL: N = 2001 families), split into HIQ, and LIQ subgroups. We did not identify any association withstanding correction for multiple testing. However, we report a replicated nominal significant under-transmission (OR < 0.79, p < 0.04) of the AKAP13 rs745191-T allele in both LIQ cohorts, but not in the much larger HIQ cohorts. At the phenotypic level, we nominally replicated associations of CAMK2A-rs2241694 with non-verbal communication in both combined LIQ and HIQ ASD cohorts. Variants PLD1-rs2124147 and ADCY1-rs2461127 were nominally associated with impaired non-verbal abilities and AKAP2-rs3739456 with repetitive behaviour in both LIQ cohorts. All four LIQ-associated genes are involved in G-protein coupled signal transduction, a downstream pathway of metabotropic glutamate receptor activation. We conclude that functional common variants of glutamatergic genes do not have a strong impact on ASD, but seem to moderately affect ASD risk and phenotypic expression. Since most of our nominally replicated hits were identified in the LIQ cohort, further investigation of the glutamatergic system in this subpopulation might be warranted.

Polymorphism in the Promoter Region of SEMA5A Is Associated with Sociality Traits in Korean Subjects with Autism Spectrum Disorders

In this study, we evaluated the association between autism spectrum disorders (ASDs) and 10 single-nucleotide polymorphisms (SNPs) in the 5' region of the semaphorin 5A gene (SEMA5A) for 250 Korean trios including children with ASDs. Family-based association testing and haplotype analysis revealed a statistically significant association between rs194085 and multiple sociality traits with Korean ASDs in the dominant model (p<0.001, corrected p=0.035). This indicates that genetic variations in the 5' region of SEMA5A play a role in the genetic predisposition to sociality traits in Korean ASDs.

[Genetic findings in autism spectrum disorders]

Autism spectrum disorders (ASD) are pervasive developmental disorders comprising problems in social interaction, communication, and stereotyped behavior and interests. They show a prevalence of around 0.8% in children, adolescents, and adults, and a skewed sex distribution (about 4:1 = male:female). ASD are predominantly genetically determined disorders. Heritability estimates from twin studies range between 64 and 91%. Recurrence risk in siblings is 20-fold elevated. De novo and inherited monogenetic disorders, mutations, sex chromosomal abnormalities, cytogenetic and imprinting disorders as well as common variants are associated with ASD. Genetic disorders implicating a specific additional intervention are of specific clinical relevance. Genetic testing and counselling should be provided for all families and individuals with ASD. This article gives an overview on current basic genetic research in ASD, its clinical relevance and genetic counselling in ASD.

Connecting Families to Their Health Record and Care Team: The Use, Utility, and Impact of a Client/Family Health Portal at a Children's Rehabilitation Hospital

Background

Health care portals have the potential to provide consumers with timely, transparent access to health care information and engage them in the care process.

Objective

The objective was to examine the use, utility, and impact on engagement in care and caregiver-provider communication of a client/family portal providing access to electronic health records (EHRs) and secure, 2-way e-messaging with care providers.

Methods

We conducted a prospective, mixed-methods study involving collection of caregivers’ portal usage information over a 14-month period (from portal introduction in January 2015 to the end of the study period in March 2016), a Web-based survey for caregivers administered after a minimum of 2 months’ exposure to the portal and repeated 2 months later, and focus groups or individual interviews held with caregivers and service providers at the same points in time. The survey assessed caregivers’ perceptions of the utility of and satisfaction with the EHR and e-messaging, and the portal’s impact on client engagement and perceptions of caregiver-provider communication. A total of 18 caregivers (parents) completed surveys and 6 also took part in focus groups or interviews. In addition, 5 service providers from different disciplines took part in focus groups or interviews.

Results

Although usage patterns varied, the typical pattern was a steady level of use (2.5 times a month over an average of 9 months), which is higher than typically reported use. The portal pages most frequently accessed were the home page, health record main page, appointment main page, and reports main page. The Web-based survey captured caregivers’ perceptions of usefulness of and satisfaction with the EHR and portal messaging, as well as the portal’s impact on their engagement in care and perceptions of caregiver-provider communication. The surveys indicated a moderate degree of utility of and satisfaction with the portal features, and a low but emerging impact on engagement in care and caregiver-provider communication (survey scales measuring these outcomes displayed excellent internal consistency, with Cronbach alpha ranging from .89 to .95). Qualitative themes from focus groups and interviews supported and extended the survey findings. Caregivers and service providers saw appreciable information benefits and provided recommendations to increase portal use and utility. Caregivers focused on the scope of organizational adoption of the portal system and indicated their hopes for the future of the portal, whereas service providers were concerned about how to best manage their investment of time and effort in preparing client-friendly reports and messaging clients via the portal.

Conclusions

Overall, the findings show the promise of the portal and the need for ongoing evaluation to show the portal’s ultimate potential in enhancing engagement in care and communication with care providers.

MLPA analysis in a cohort of patients with autism

Background

Autism is a global neurodevelopmental disorder which generally manifests during the first 2 years and continues throughout life, with a range of symptomatic variations. Epidemiological studies show an important role of genetic factors in autism and several susceptible regions and genes have been identified. The aim of our study was to validate a cost-effective set of commercial Multiplex Ligation dependent Probe Amplification (MLPA) and methylation specific multiplex ligation dependent probe amplification (MS-MLPA) test in autistic children refered by the neurodevelopmental center and autism unit of a Paediatric Hospital.

Results

In this study 150 unrelated children with autism spectrum disorders were analysed for copy number variation in specific regions of chromosomes 15, 16 and 22, using MLPA. All the patients had been previously studied by conventional karyotype and fluorescence in situ hybridization (FISH) analysis for 15(q11.2q13) and, with these techniques, four alterations were identified. The MLPA technique confirmed these four and identified further six alterations by the combined application of the two different panels.

Conclusions

Our data show that MLPA is a cost effective straightforward and rapid method for detection of imbalances in a clinically characterized population with autism. It contributes to strengthen the relationship between genotype and phenotype of children with autism, showing the clinical difference between deletions and duplications.

Modeling autism spectrum disorders with human neurons

Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders characterized by impaired social communication and interactions and by restricted and repetitive behaviors. Although ASD is suspected to have a heritable or sporadic genetic basis, its underlying etiology and pathogenesis are not well understood. Therefore, viable human neurons and glial cells produced using induced pluripotent stem cells (iPSC) to reprogram cells from individuals affected with ASD provide an unprecedented opportunity to elucidate the pathophysiology of these disorders, providing novel insights regarding ASD and a potential platform to develop and test therapeutic compounds. Herein, we discuss the state of art with regards to ASD modeling, including limitations of this technology, as well as potential future directions. This article is part of a Special Issue entitled SI: Exploiting human neurons.

[Pre- and perinatal risk factors in autism spectrum disorder and attention deficit/hyperactivity disorder]

Objective

Epidemiological studies indicate the relevance of pre- and perinatal risk factors for the genesis of attention deficit/hyperactivity disorder and autism spectrum disorder. This study compares potential risk factors in a clinical sample of children with ADHD, ASD, the combination of both diseases, ADHD and oppositional defiant or conduct disorder (ADHD & ODD/CD) and examined whether the existence of additional risk factors promotes the occurrence of combined diseases.

Method

We compared the pre- and perinatal risk factors of 341 patients (299 boys, 42 girls) from a clinical population, differentiating between children with ADHD (n=80), ASD (n=122), ADHD & ASD (n=55), or ADHD & ODD/CD (n=84).

Results

We observed a higher rate of maternal smoking, a higher rate of migration, and lower parental education among the children with ADHD & ODD/CD compared to those with ASD or ADHD. The rate of migration background was higher among the children with ASD compared to children with ADHD. Miscarriage was a specific risk factor for ADHD & ASD.

Conclusion

Numerous risk factors described in epidemiological studies occurred only rarely in our clinical sample. The distribution of most risk factors was comparable between the examined diseases.

Vitamin D status in autism spectrum disorders and the efficacy of vitamin D supplementation in autistic children

OBJECTIVES

Autism spectrum disorder (ASD) is a developmental disorder characterized by pervasive deficits in social interaction, impairment in verbal and non-verbal communication, and stereotyped patterns of interests and activities. Vitamin-D deficiency was previously reported in autistic children. However, the data on the relationship between vitamin D deficiency and the severity of autism are limited.

METHODS

We performed a case-controlled cross-sectional analysis conducted on 122 ASD children, to assess their vitamin D status compared to controls and the relationship between vitamin D deficiency and the severity of autism. We also conducted an open trial of vitamin D supplementation in ASD children.

RESULTS

Fifty-seven percent of the patients in the present study had vitamin D deficiency, and 30% had vitamin D insufficiency. The mean 25-OHD levels in patients with severe autism were significantly lower than those in patients with mild/moderate autism. Serum 25-OHD levels had significant negative correlations with Childhood Autism Rating Scale (CARS) scores. Of the ASD group, 106 patients with low-serum 25-OHD levels (<30 ng/ml) participated in the open label trial. They received vitamin D3 (300 IU/kg/day not to exceed 5000 IU/day) for 3 months. Eighty-three subjects completed 3 months of daily vitamin D treatment. Collectively, 80.72% (67/83) of subjects who received vitamin D3 treatment had significantly improved outcome, which was mainly in the sections of the CARS and aberrant behavior checklist subscales that measure behavior, stereotypy, eye contact, and attention span.

CONCLUSION

Vitamin D is inexpensive, readily available and safe. It may have beneficial effects in ASD subjects, especially when the final serum level is more than 40 ng/ml.

TRIAL REGISTRATION NUMBER

UMIN-CTR Study Design: trial Number: R000016846.

The genetic architecture of autism spectrum disorders (ASDs) and the potential importance of common regulatory genetic variants

Currently, there is great interest in identifying genetic variants that contribute to the risk of developing autism spectrum disorders (ASDs), due in part to recent increases in the frequency of diagnosis of these disorders worldwide. While there is nearly universal agreement that ASDs are complex diseases, with multiple genetic and environmental contributing factors, there is less agreement concerning the relative importance of common vs rare genetic variants in ASD liability. Recent observations that rare mutations and copy number variants (CNVs) are frequently associated with ASDs, combined with reduced fecundity of individuals with these disorders, has led to the hypothesis that ASDs are caused primarily by de novo or rare genetic mutations. Based on this model, large-scale whole-genome DNA sequencing has been proposed as the most appropriate method for discovering ASD liability genes. While this approach will undoubtedly identify many novel candidate genes and produce important new insights concerning the genetic causes of these disorders, a full accounting of the genetics of ASDs will be incomplete absent an understanding of the contributions of common regulatory variants, which are likely to influence ASD liability by modifying the effects of rare variants or, by assuming unfavorable combinations, directly produce these disorders. Because it is not yet possible to identify regulatory genetic variants by examination of DNA sequences alone, their identification will require experimentation. In this essay, I discuss these issues and describe the advantages of measurements of allelic expression imbalance (AEI) of mRNA expression for identifying cis-acting regulatory variants that contribute to ASDs.

Focal atrophy of the hypothalamus associated with third ventricle enlargement in autism spectrum disorder

The hypothalamus is a brain structure containing multiple nuclei that mediate essential behavioral, autonomic, and endocrine functions including oxytocin synthesis. Oxytocin is a neuropeptide linked to complex social cognition and behaviors necessary for an effective social interaction. Oxytocinergic system dysfunction has been linked to social deficits in autism spectrum disorders (ASD). Limited studies have been carried out on the hypothalamus because of its small size and methodological constraints in current technologies. This neuroimaging study examines hypothalamic atrophy in ASD in comparison with a typically developing population (a) by directly measuring gray matter (GM) density with a region-of-interest analysis using voxel-based morphometry in a homogenous sample of participants controlled for age and intelligence quotient; (b) for generalization, by measuring third ventricular volume, on the basis of its position bilaterally surrounded by the hypothalamus, using Freesurfer in a heterogeneous sample of participants. A voxel-based morphometry analysis of cerebrospinal fluid density on the first sample provides a link between GM density and third ventricle volume. Our results show decreased hypothalamic GM density and increased third ventricle volume in ASD compared with typically developing patients. Our findings provide neuroanatomical insights into social deficits in ASD within the hypothalamus that might be relevant for other psychiatric conditions.

Autism spectrum disorder in adults: diagnosis, management, and health services development

Autism spectrum disorder (ASD) is a common neurodevelopmental disorder characterized by pervasive difficulties since early childhood across reciprocal social communication and restricted, repetitive interests and behaviors. Although early ASD research focused primarily on children, there is increasing recognition that ASD is a lifelong neurodevelopmental disorder. However, although health and education services for children with ASD are relatively well established, service provision for adults with ASD is in its infancy. There is a lack of health services research for adults with ASD, including identification of comorbid health difficulties, rigorous treatment trials (pharmacological and psychological), development of new pharmacotherapies, investigation of transition and aging across the lifespan, and consideration of sex differences and the views of people with ASD. This article reviews available evidence regarding the etiology, legislation, diagnosis, management, and service provision for adults with ASD and considers what is needed to support adults with ASD as they age. We conclude that health services research for adults with ASD is urgently warranted. In particular, research is required to better understand the needs of adults with ASD, including health, aging, service development, transition, treatment options across the lifespan, sex, and the views of people with ASD. Additionally, the outcomes of recent international legislative efforts to raise awareness of ASD and service provision for adults with ASD are to be determined. Future research is required to identify high-quality, evidence-based, and cost-effective models of care. Furthermore, future health services research is also required at the beginning and end of adulthood, including improved transition from youth to adult health care and increased understanding of aging and health in older adults with ASD.

Acid glycosaminoglycan (aGAG) excretion is increased in children with autism spectrum disorder, and it can be controlled by diet

Autism research continues to receive considerable attention as the options for successful management are limited. The understanding of the autism spectrum disorder (ASD) etiology has now progressed to encompass genetic, epigenetic, neurological, hormonal, and environmental factors that affect outcomes for patients with ASD. Glycosaminoglycans (GAGs) are a family of linear, sulfated polysaccharides that are associated with central nervous system (CNS) development, maintenance, and disorders. Proteoglycans (PG) regulate diverse functions in the central nervous system. Heparan sulfate (HS) and chondroitin sulfate (CS) are two major GAGs present in the PGs of the CNS. As neuroscience advances, biochemical treatments to correct brain chemistry become better defined. Nutrient therapy can be very potent and has minimal to no side effects, since no molecules foreign to the body are needed. Given GAGs are involved in several neurological functions, and that its level can be somewhat modulated by the diet, the present study aimed to evaluate the role of GAGs levels in ASD symptoms. Both tGAG and its different fractions were evaluated in the urine of ASD and healthy control childrens. As levels differed between groups, a second trial was conduted evaluating if diet could reduce tGAG levels and if this in turn decrease ASD symptoms. The present study found that tGAG concentration was significantly higher in the urine of children with ASD compared to healthy control children and this was also evident in all GAG fractions. Within groups (controls and ASD), no gender differences in GAG excretion were found. The use of a 90 days elimination diet (casein-free, special carbohydrates, multivitamin/mineral supplement), had major effects in reducing urinary tGAG excretion in children with ASD.

Serum concentration of 25-hydroxyvitamin D in autism spectrum disorder: a systematic review and meta-analysis

Vitamin D may play an important role in the etiology of Autism Spectrum Disorders (ASD). Vitamin D is regarded as a neuroactive steroid affecting brain development and function. It plays an essential role in myelination, which is important for connectivity in the brain. Studies have shown that decreased vitamin D levels in patients, decreased maternal vitamin D levels during pregnancy, and decreased exposure to solar UVB might increase the risk for ASD. In addition, autism symptoms and global functioning may improve after vitamin D supplementation. Here, we sought to aggregate information from previous publications on vitamin D levels and ASD, in order to achieve a higher statistical power and thereby to determine the validity of vitamin D deficiency as a risk factor for ASD. For this meta-analysis, 11 studies met the inclusion and exclusion criteria, accounting for a total of 870 ASD patients and 782 healthy controls. Levels of serum 25(OH) D in participants with ASD were significantly lower than controls, suggesting that lower vitamin D level might be a risk factor for ASD.

Autism Spectrum Disorder - A Complex Genetic Disorder

Autism spectrum disorder is an entity that reflects a scientific consensus that several previously separated disorders are actually a single spectrum disorder with different levels of symptom severity in two core domains - deficits in social communication and interaction, and restricted repetitive behaviors. Autism spectrum disorder is diagnosed in all racial, ethnic and socioeconomic groups and because of its increased prevalence, reported worldwide through the last years, made it one of the most discussed child psychiatric disorders. In term of aetiology as several other complex diseases, Autism spectrum disorder is considered to have a strong genetic component.

CNTNAP2 gene in high functioning autism: no association according to family and meta-analysis approaches

The Contactin Associated Protein-like 2 (CNTNAP2) gene has been discussed to be associated with different symptoms of autism spectrum disorders (ASDs) and other neurodevelopmental disorders. We aimed to elucidate the genetic association of CNTNAP2 within high functioning ASD (HFA), focusing on autism specific symptoms and reducing intelligence related factors. Furthermore, we compared our findings conducting a meta-analysis in patients with ASD and HFA only. A case-control association study was performed for HFA (HFA, n = 105; controls, n = 133). Moreover, we performed a family-based association study (DFAM) analysis (HFA, n = 44; siblings, n = 57). Individuals were genotyped for the two most frequently reported single nucleotide polymorphisms (SNPs) in the CNTNAP2 gene (rs2710102, rs7794745). Furthermore, a meta-analysis using the MIX2 software integrated our results with previously published data. A significant association for the carriers of the T-allele of the rs7794745 with HFA was found in the case-control sample [OR = 1.547; (95 % CI 1.056-2.266); p = 0.025]. No association could be found by DFAM with any of the CNTNAP2 SNPs with HFA. The meta-analysis of both SNPs did not show a significant association with either ASD or with HFA. Overall, including case-control, sibs, and meta-analysis, we could not detect any significant association with the CNTNAP2 gene and HFA. Our results point in the direction that CNTNAP2 may not play a major role in HFA, but rather seems to have a significance in neurodevelopmental disorders or in individuals displaying intellectual delays.

Prenatal acquired cytomegalovirus infection should be considered in children with autism

AIM

The aim of the study was to evaluate the prevalence of congenital cytomegalovirus infection (CMV) in a representative sample of children with autism spectrum disorder.

METHODS

In a representative group of 115 preschool children with autism spectrum disorder, of whom 33 also had intellectual disability, the dried blood spots from the newborn metabolic screening were analysed for CMV DNA using TaqMan polymerase chain reaction.

RESULTS

One of the 33 children with autism spectrum disorder and intellectual disability - 3% of that group - had congenital CMV infection. The corresponding prevalence in newborn infants in Sweden is 0.2%. None of the 82 children without intellectual disability had congenital CMV.

CONCLUSION

The finding lends some further support for congenital CMV being one of the many aetiologies underlying autism spectrum disorder with intellectual disability. The rate of 3% of congenital CMV in children with autism spectrum disorder with intellectual disability has implications for the medical work-up. The finding of congenital CMV also indicates the need for repeated hearing assessments in the child. There is a need for similar studies with much larger samples.

Neuroimaging endophenotypes in autism spectrum disorder

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that has a strong genetic basis, and is heterogeneous in its etiopathogenesis and clinical presentation. Neuroimaging studies, in concert with neuropathological and clinical research, have been instrumental in delineating trajectories of development in children with ASD. Structural neuroimaging has revealed ASD to be a disorder with general and regional brain enlargement, especially in the frontotemporal cortices, while functional neuroimaging studies have highlighted diminished connectivity, especially between frontal-posterior regions. The diverse and specific neuroimaging findings may represent potential neuroendophenotypes, and may offer opportunities to further understand the etiopathogenesis of ASD, predict treatment response, and lead to the development of new therapies.

Variants of the CNTNAP2 5' promoter as risk factors for autism spectrum disorders: a genetic and functional approach

Contactin-associated protein-like 2 gene (CNTNAP2), a member of the Neurexin gene superfamily, is one of the best-replicated risk genes for autism spectrum disorders (ASD). ASD are predominately genetically determined neurodevelopmental disorders characterized by impairments of language development, social interaction and communication, as well as stereotyped behavior and interests. Although CNTNAP2 expression levels were proposed to alter ASD risk, no study to date has focused on its 5' promoter. Here, we directly sequenced the CNTNAP2 5' promoter region of 236 German families with one child with ASD and detected four novel variants. Furthermore, we genotyped the three most frequent variants (rs150447075, rs34712024, rs71781329) in an additional sample of 356 families and found nominal association of rs34712024G with ASD and rs71781329GCG[7] with language development. The four novel and the three known minor alleles of the identified variants were predicted to alter transcription factor binding sites (TFBS). At the functional level, the respective sequences spanning these seven variants were bound by nuclear factors. In a luciferase promoter assay, the respective minor alleles showed cell line-specific and differentiation stage-dependent effects at the level of promoter activation. The novel potential rare risk-variant M2, a G>A mutation -215 base pairs 5' of the transcriptional start site, significantly reduced promoter efficiency in HEK293T and in undifferentiated and differentiated neuroblastoid SH-SY5Y cells. This variant was transmitted to a patient with autistic disorder. The under-transmitted, protective minor G allele of the common variant rs34712024, in contrast, increased transcriptional activity. These results lead to the conclusion that the pathomechanism of CNTNAP2 promoter variants on ASD risk is mediated by their effect on TFBSs, and thus confirm the hypothesis that a reduced CNTNAP2 level during neuronal development increases liability for ASD.

The oxytocin receptor gene (OXTR) is associated with autism spectrum disorder: a meta-analysis

The oxytocin receptor gene (OXTR) has been studied as a risk factor for autism spectrum disorder (ASD) owing to converging evidence from multiple levels of analysis that oxytocin (OXT) has an important role in the regulation of affiliative behavior and social bonding in both nonhuman mammals and humans. Inconsistency in the effect sizes of the OXTR variants included in association studies render it unclear whether OXTR is truly associated with ASD, and, if so, which OXTR single-nucleotide polymorphisms (SNPs) are associated. Thus, a meta-analytic review of extant studies is needed to determine whether OXTR shows association with ASD, and to elucidate which specific SNPs have a significant effect on ASD. The current meta-analysis of 16 OXTR SNPs included 3941 individuals with ASD from 11 independent samples, although analyses of each individual SNP included a subset of this total. We found significant associations between ASD and the SNPs rs7632287, rs237887, rs2268491 and rs2254298. OXTR was also significantly associated with ASD in a gene-based test. The current meta-analysis is the largest and most comprehensive investigation of the association of OXTR with ASD and the findings suggest directions for future studies of the etiology of ASD.