Background Mutations in Ras/mitogen-activated protein kinase (Ras/MAPK) pathway genes lead to a class of disorders known as RASopathies, including neurofibromatosis type 1 (NF1), Noonan syndrome (NS), Costello syndrome (CS), and cardio-facio-cutaneous syndrome (CFC). Previous work has suggested potential genetic and phenotypic overlap between dysregulation of Ras/MAPK signalling and autism spectrum disorders (ASD). Although the literature offers conflicting evidence for association of NF1 and autism, there has been no systematic evaluation of autism traits in the RASopathies as a class to support a role for germline Ras/MAPK activation in ASDs. Methods We examined the association of autism traits with NF1, NS, CS and CFC, comparing affected probands with unaffected sibling controls and subjects with idiopathic ASDs using the qualitative Social Communication Questionnaire (SCQ) and the quantitative Social Responsiveness Scale (SRS). Results Each of the four major RASopathies showed evidence for increased qualitative and quantitative autism traits compared with sibling controls. Further, each RASopathy exhibited a distinct distribution of quantitative social impairment. Levels of social responsiveness show some evidence of correlation between sibling pairs, and autism-like impairment showed a male bias similar to idiopathic ASDs. Conclusions Higher prevalence and severity of autism traits in RASopathies compared to unaffected siblings suggests that dysregulation of Ras/MAPK signalling during development may be implicated in ASD risk. Evidence for sex bias and potential sibling correlation suggests that autism traits in the RASopathies share characteristics with autism traits in the general population and clinical ASD population and can shed light on idiopathic ASDs.

Autism spectrum disorders (ASDs) are complex, heterogeneous disorders caused by an interaction between genetic vulnerability and environmental factors. In an effort to better target the underlying roots of ASD for diagnosis and treatment, efforts to identify reliable biomarkers in genetics, neuroimaging, gene expression, and measures of the body’s metabolism are growing. For this article, we review the published studies of potential biomarkers in autism and conclude that while there is increasing promise of finding biomarkers that can help us target treatment, there are none with enough evidence to support routine clinical use unless medical illness is suspected. Promising biomarkers include those for mitochondrial function, oxidative stress, and immune function. Genetic clusters are also suggesting the potential for useful biomarkers.

Objective Preliminary evidence suggests that omega-3 fatty acids may reduce hyperactivity in children with autism spectrum disorder (ASD). We sought to examine the feasibility of a novel, internet-based clinical trial design to evaluate the efficacy of this supplement. Method E-mail invitations were sent to parents of children aged 5-8 enrolled in the Interactive Autism Network. All study procedures, including screening, informed consent, and collection of outcome measures took place over the internet. The primary outcome measures were parent- and teacher-rated changes in hyperactivity on the Aberrant Behavior Checklist. Results During the 6-week recruitment period, 57 children from 28 states satisfied all eligibility criteria and were randomly assigned to 1.3 grams of omega-3 fatty acids or an identical placebo daily for 6 weeks. Outcome assessments were obtained from all 57 participants and 57 teachers, and the study was completed in 3 months. Children in the omega-3 fatty acid group had a greater reduction in hyperactivity (-5.3 points) compared to the placebo group (-2.6 points), but the difference was not statistically significant (1.9 point greater improvement in the omega-3 group, 95% CI -2.2 to 5.2). Side effects were rare and not associated with omega-3 fatty acids. Participant feedback was positive. Conclusion Internet-based randomized controlled trials of therapies in children with ASD are feasible and may lead to marked reductions in the time and cost of completing trials. A larger sample size is required to definitively determine the efficacy of omega-3 fatty acids. Clinical trial registration information—Omega-3 Fatty Acids for Hyperactivity Treatment in Autism Spectrum Disorder; http://clinicaltrials.gov; NCT01694667.

Objective: Children with autism spectrum disorder (ASD) have been reported to have reduced ability to methylate DNA and elevated markers of oxidative stress. We sought to determine if methyl B12, a key metabolic cofactor for cellular methylation reactions and antioxidant defense, could improve symptoms of ASD. Methods: A total of 57 children with ASD were randomly assigned to 8 weeks of treatment with methyl B12 (75 lg/kg) or saline placebo every 3 days in a subcutaneous injection. The primary outcome measure was overall improvement in symptoms of ASD as measured by the Clinical Global Impressions-Improvement (CGI-I) score. Secondary outcome measures included changes in the Aberrant Behavior Checklist (ABC) and the Social Responsiveness Scale (SRS). Laboratory measures of methionine methylation and antioxidant glutathione metabolism were assessed at baseline and 8 weeks.Results: A total of 50 children (mean age 5.3 years, 79% male) completed the study. The primary outcome measure -the clinician rated CGI-I score -was statistically significantly better (lower) in the methyl B12 group (2.4) than in the placebo group (3.1) (0.7 greater improvement in the methyl B12 group, 95% CI 1.2-0.2, p = 0.005). Clinical improvement among children treated with methyl B12 was positively correlated with increases in plasma methionine ( p = 0.05), decreases in S-adenosyl-lhomocysteine (SAH) ( p = 0.007) and improvements in the ratio of S-adenosylmethionine (SAM) to SAH ( p = 0.007), indicating an improvement in cellular methylation capacity. No improvements were observed in the parent-rated ABC or SRS. Conclusions: Methyl B12 treatment improved clinician-rated symptoms of ASD that were correlated with improvements in measures of methionine metabolism and cellular methylation capacity. Clinical Trial Registry: Efficacy Study of Subcutaneous Methyl B12 in Children with Autism: NCT01039792 (clinical trials.gov1).

BackgroundChildren with autism spectrum disorder (ASD) have urinary metabolites suggesting impairments in several pathways, including oxidative stress, inflammation, mitochondrial dysfunction, and gut microbiome alterations. Sulforaphane, a supplement with indirect antioxidant effects that are derived from broccoli sprouts and seeds, was recently shown to lead to improvements in behavior and social responsiveness in children with ASD. We conducted the current open-label study to determine if we could identify changes in urinary metabolites that were associated with clinical improvements with the goal of identifying a potential mechanism of action.MethodsChildren and young adults enrolled in a school for children with ASD and related neurodevelopmental disorders were recruited to participate in a 12-week, open-label study of sulforaphane. Fasting urinary metabolites and measures of behavior (Aberrant Behavior Checklist—ABC) and social responsiveness (Social Responsiveness Scale—SRS) were measured at baseline and at the end of the study. Pearson’s correlation coefficient was calculated for the pre- to post-intervention change in each of the two clinical scales (ABS and SRS) versus the change in each metabolite.ResultsFifteen children completed the 12-week study. Mean scores on both symptom measures showed improvements (decreases) over the study period, but only the change in the SRS was significant. The ABC improved − 7.1 points (95% CI − 17.4 to 3.2), and the SRS improved − 9.7 points (95% CI − 18.7 to − 0.8). We identified 77 urinary metabolites that were correlated with changes in symptoms, and they clustered into pathways of oxidative stress, amino acid/gut microbiome, neurotransmitters, hormones, and sphingomyelin metabolism.ConclusionsUrinary metabolomics analysis is a useful tool to identify pathways that may be involved in the mechanism of action of treatments targeting abnormal physiology in ASD.Trial registrationThis study was prospectively registered at clinicaltrials.gov (NCT02654743) on January 11, 2016.