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Autism ableism seen through research abstract contents: A mixed-methods analysis of language in NIH-funded genetic and genomic autism research.

In recent years, genetic and genomic autism research has come under increasing scrutiny, moving to the center of debates about ableism, neurodiversity, autism acceptance, and the future of research and care. At the same time, both autism research and genetics and genomics research have, as fields, begun to reckon with the significance of the language researchers use in the course of their work and the harmful ideas that may thereby be reinforced. Although the language of research cannot be assumed to straightforwardly correspond to individual researchers' beliefs, the presence of widespread ableist language may indicate structural and institutionalized ableism, including ableist assumptions at the foundations of research. We conducted a mixed-methods analysis of 166 genetic and genomic autism research projects funded by the US National Institutes of Health, in order to understand the prevalence of potentially ableist discourse, language, and stigmatizing language about autistic people. We found that such discourse and language was ubiquitous across our sample, including a discourse of prevention. This study lends empirical evidence to current debates about language in autism research. Evaluating language can prompt researchers and institutions to reflect on how they conceptualize, design, discuss, and pursue their work.Lay abstractGenetic research about autism is controversial. Researchers are starting to think more carefully about the words they use to talk about autism and the way they do their research. Past research has found that researchers sometimes write about autism in ableist ways. This means that they write about autistic people as though they are less important than nonautistic people. We looked at the way genetics researchers have written about autism in the paperwork for their research. We found that they often write about autistic people in an ableist way. We think that researchers should think carefully about the way they write about autistic people, and how they plan and do their research.

Humans

The Association of Prenatal Dietary Factors with Child Autism Diagnosis and Autism-Related Traits Using a Mixtures Approach: Results from the Environmental Influences on Child Health Outcomes Cohort.

BACKGROUND: Previous research on the role of maternal diet in relation to autism has focused on examining individual nutrient associations. Few studies have examined associations with multiple nutrients using mixtures approaches, which may better reflect true exposure scenarios. OBJECTIVES: This study aims to examine associations of nutrient mixtures with children's autism diagnosis and trait scores within a large, diverse population. METHODS: Participants were drawn from the United States Environmental influences on Child Health Outcomes (ECHO) consortium. Maternal prenatal diet was reported via validated food frequency questionnaires. Children's autism-related traits were measured using the Social Responsiveness Scale (SRS) and autism diagnoses were from parent reports of physician diagnosis. Bayesian kernel machine regression was used to examine the overall mixture effect and interactions between a set of 5 primary nutrients (folate, vitamin D, omega 3 and omega 6 fatty acids, and iron), adjusted for potential confounders, in relationship to child outcomes. Secondary analyses were conducted in a subset of cohorts with an expanded set of 14 nutrients. Traditional linear and logistic regression models were also analyzed for comparison of results to mixture models. RESULTS: A total of 2614 participants drawn from 7 ECHO cohorts were included in primary analysis. Mixture analyses suggested that increasing the overall 5-nutrient mixture was associated with lower SRS scores. Individual U-shaped associations and bivariate interactions between folate and omega 3 fatty acids were suggested. In the subset included in the secondary analyses of the 14-nutrient mixture, a modest inverse trend remained, but individual nutrient associations were altered, with vitamin D demonstrating higher relative importance than other nutrients. Strong associations with autism diagnosis were not observed. CONCLUSIONS: In this large sample, we found evidence for combined nutrient effects with broader autism-related traits. Because results for individual nutrients were sensitive to mixture components, replication of combined associations between nutrients and autism-related outcomes is needed.

Humans

Polygenic and developmental profiles of autism differ by age at diagnosis.

Although autism has historically been conceptualized as a condition that emerges in early childhood1,2, many autistic people are diagnosed later in life3-5. It is unknown whether earlier- and later-diagnosed autism have different developmental trajectories and genetic profiles. Using longitudinal data from four independent birth cohorts, we demonstrate that two different socioemotional and behavioural trajectories are associated with age at diagnosis. In independent cohorts of autistic individuals, common genetic variants account for approximately 11% of the variance in age at autism diagnosis, similar to the contribution of individual sociodemographic and clinical factors, which typically explain less than 15% of this variance. We further demonstrate that the polygenic architecture of autism can be broken down into two modestly genetically correlated (rg = 0.38, s.e. = 0.07) autism polygenic factors. One of these factors is associated with earlier autism diagnosis and lower social and communication abilities in early childhood, but is only moderately genetically correlated with attention deficit-hyperactivity disorder (ADHD) and mental-health conditions. Conversely, the second factor is associated with later autism diagnosis and increased socioemotional and behavioural difficulties in adolescence, and has moderate to high positive genetic correlations with ADHD and mental-health conditions. These findings indicate that earlier- and later-diagnosed autism have different developmental trajectories and genetic profiles. Our findings have important implications for how we conceptualize autism and provide a model to explain some of the diversity found in autism.

Humans

Polygenic and developmental profiles of autism differ by age at diagnosis.

Although autism has been historically conceptualised as a condition that emerges in early childhood, many autistic people are diagnosed later in life. It is unknown whether earlier and later diagnosed autism have different developmental trajectories and genetic profiles. Using longitudinal data from four independent birth cohorts, we demonstrate that two different socioemotional and behavioural trajectories are associated with age at diagnosis. In independent cohorts of autistic individuals, common genetic variants account for approximately 11% of the variance in age at autism diagnosis, comparable to the contribution of individual sociodemographic and clinical factors, which typically explain less than 15% of this variance. We further demonstrate that the polygenic architecture of autism can be decomposed into two modestly genetically correlated (rg = 0.38, SE = 0.07) autism polygenic factors. One of these factors is associated with earlier autism diagnosis, and lower social and communication abilities in early childhood but is only modestly genetically correlated with ADHD and mental health conditions. Conversely, the second factor is associated with later autism diagnosis, increased socioemotional and behavioural difficulties in adolescence, and has moderate to high positive genetic correlations with Attention-Deficit/Hyperactivity Disorder and mental health conditions. These findings indicate that earlier and later diagnosed autism have different developmental trajectories and genetic profiles. Our findings have important implications for how we conceptualise autism and provide one model to explain some of the diversity within autism.

Journal Article

Convergence on CaMK4: A Key Modulator of Autism-Associated Signaling Pathways in Neurons.

Although the precise underlying cause(s) of autism spectrum disorder remain unclear, more than 1000 rare genetic variations are associated with the condition. For many people living with profound autism, this genetic heterogeneity has impeded the identification of common biological targets for therapy development for core and comorbid traits that include significant impairments in social communication and repetitive and restricted behaviors. A substantial number of genes associated with autism encode proteins involved in signal transduction and synaptic transmission that are critical for brain development and function. CAMK4 is an emerging risk gene for autism spectrum disorder that encodes the CaMK4 (calcium/calmodulin-dependent protein kinase 4) enzyme. CaMK4 is a key component of a Ca2+-activated signaling pathway that regulates neurodevelopment and synaptic plasticity. In this review, we discuss 3 genetic variants of CAMK4 found in individuals with hyperkinetic movement disorder and comorbid neurological symptoms including autism spectrum disorder that are likely pathogenic with monogenic effect. We also comment on 4 other genetic variations in CAMK4 that show associations with autism spectrum disorder, as well as 12 examples of autism-associated variations in other genes that impact CaMK4 signaling pathways. Finally, we highlight 3 environmental risk factors that impact CaMK4 signaling based on studies of preclinical models of autism and/or clinical cohorts. Overall, we review molecular, genetic, physiological, and environmental evidence that suggest that defects in the CaMK4 signaling pathway may play an important role in a common autism pathogenesis network across numerous patient groups, and we propose CaMK4 as a potential therapeutic target.

Humans

Sex differences in MAGEL2 gene promoter methylation in high functioning autism - trends from a pilot study using nanopore Cas9 targeted long read sequencing.

BACKGROUND: MAGEL2 is an autism susceptibility gene whose deficiency has been associated with autism-related behaviors in animal models and in syndromic human autism spectrum disorders (ASDs) such as Schaaf-Yang syndrome, but has not been studied in the broader autism spectrum. Given the capabilities of long-read sequencing technologies, this pilot study used a targeted nanopore sequencing approach to simultaneously examine MAGEL2 DNA sequence and methylation in adults with high-functioning autism (HFA) compared to neurotypical controls (NC). METHODS: Using DNA extracted from peripheral blood, Cas9-targeted nanopore DNA sequencing was used to analyze MAGEL2, including its entire regulatory construct (chr15:23639316-23651466), for sequence variation and 5-methyl-cytosine (5mC) modification in a cohort of adults with HFA compared to sex- and age-matched NC. Given the known sex differences in ASD and MAGEL2 KO animal models, results were further analyzed by sex. RESULTS: 20 adults with HFA (10 males, 10 females) and 20 NC were included. While there were no overall differences in MAGEL2 DNA sequence and 5mC modification between HFA and NC, we found a significant difference in MAGEL2 gene promoter methylation between males and females with HFA and NC of both sexes, with HFA males tending to show hypomethylation in a 300 bp long differentially methylated region (chr15:23647640-23647939) around the MAGEL2 transcription start site. CONCLUSIONS: In this pilot study utilizing nanopore Cas9 targeted DNA sequencing, significant sex-specific differences in MAGEL2 gene promoter methylation were identified in male adults with HFA in comparison to control groups, suggesting the potential for sex-specific epigenetic differences. However, further replication in larger cohorts is required to validate these findings.

Humans

Atypical cytokine profiles in people on the autism spectrum: a comprehensive systematic review and meta-analysis including 54 cytokines.

Atypical peripheral blood cytokine concentrations have been shown in autism, but no clear pattern has been observed. This systematic review and meta-analysis summarised current state of findings, expanded the range of cytokines, accounted for study risk of bias, and examined relations between cytokines and autism traits. Literature comparing peripheral blood cytokine in autistic and non-autistic people was systematically searched in Ovid® Embase, MEDLINE and APA PsycINFO, Web of Science™ and Scopus, resulting in 98 studies and 54 cytokines (4236 autistic, 3333 non-autistic controls; age 2 to 65 years) in the meta-analysis. Study risk of bias was assessed using adapted Newcastle-Ottawa Scale. Compared to controls, autistic people had elevated levels of IL1-beta (Hedges' g = 0.620, 95%CI[0.32, 0.92]), IL4 (g = 0.245, 95%CI [0.07, 0.42]), IL6 (g = 0.365, 95%CI [0.011, 0.62]), IL8 (g = 0.384, 95%CI [0.15, 0.62]), IFN-gamma (g = 0.404, 95%CI [0.09, 0.72]), TNF-alpha (g = 0.31, 95%CI [0.11, 0.51]), CXCL1/GRO-α (g = 0.364, 95%CI [0.058, 0.670]) and MIF (g = 0.560, 95%CI [0.14, 0.98]). Over a third of studies were classified as having a high risk of bias; their removal revealed higher IL7 and IL1RA in autism relative to controls. Narrative synthesis produced no strong evidence for an association between cytokine and autism traits among autistic individuals. Altogether, our findings support a predominance of pro-inflammatory cytokines, while also indicating potential modulatory contributions from inhibitory cytokines, which reflect group-level differences between autistic and non-autistic individuals, but not variations of autism traits within the autistic population. However, higher-quality studies with low risk of bias are needed before firm conclusions can be drawn.

Humans

From genotype to phenotype: understanding the genetic basis of autism.

PURPOSE OF REVIEW: This paper covers some of the key findings on the topic of genetic influences in autism over the last 12-18 months, which consist of significant conceptual shifts and new insights from recent technological advances. RECENT FINDINGS: Autism is a highly heritable condition, with significant heterogeneity of the genes that influence the development of this condition. The heterogeneity of autism, and multiple pathways contributing to the development of an autistic phenotype, create challenges in our understanding, diagnosis, and management of this condition.Recent studies of common genetic variation and polygenic risk scores have focussed on resolving phenotypic heterogeneity and identifying meaningful autism subtypes. Rare-variant discovery has expanded across ancestries, the X chromosome, noncoding loci, structural variants, and tandem repeats, aided by long-read and pangenome-informed sequencing. Single-cell multiomics, spatial perturbation methods and human organoid models have connected genetic variation to cell-type-specific and developmental phenotypes, while also revealing substantial mutation-specific effects and methodological sensitivity. Genetic testing increasingly provides aetiological diagnoses and informs medical surveillance. Recent developments also illustrate the therapeutic potential of gene-first approaches for selected monogenic neurodevelopmental disorders. SUMMARY: Recent developments have expanded our understanding of the way the genetic basis of autism manifests phenotypically.

autism

Exome sequencing reveals neurodevelopmental genes in simplex consanguineous Iranian families with syndromic autism.

BACKGROUND AND OBJECTIVE: Autosomal recessive genetic disorders pose significant health challenges in regions where consanguineous marriages are prevalent. The utilization of exome sequencing as a frequently employed methodology has enabled a clear delineation of diagnostic efficacy and mode of inheritance within multiplex consanguineous families. However, these aspects remain less elucidated within simplex families. METHODS: In this study involving 12 unrelated simplex Iranian families presenting syndromic autism, we conducted singleton exome sequencing. The identified genetic variants were validated using Sanger sequencing, and for the missense variants in FOXG1 and DMD, 3D protein structure modeling was carried out to substantiate their pathogenicity. To examine the expression patterns of the candidate genes in the fetal brain, adult brain, and muscle, RT-qPCR was employed. RESULTS: In four families, we detected an autosomal dominant gene (FOXG1), an autosomal recessive gene (CHKB), and two X-linked autism genes (IQSEC2 and DMD), indicating diverse inheritance patterns. In the remaining eight families, we were unable to identify any disease-associated genes. As a result, our variant detection rate stood at 33.3% (4/12), surpassing rates reported in similar studies of smaller cohorts. Among the four newly identified coding variants, three are de novo (heterozygous variant p.Trp546Ter in IQSEC2, heterozygous variant p.Ala188Glu in FOXG1, and hemizygous variant p.Leu211Met in DMD), while the homozygous variant p.Glu128Ter in CHKB was inherited from both healthy heterozygous parents. 3D protein structure modeling was carried out for the missense variants in FOXG1 and DMD, which predicted steric hindrance and spatial inhibition, respectively, supporting the pathogenicity of these human mutants. Additionally, the nonsense variant in CHKB is anticipated to influence its dimerization - crucial for choline kinase function - and the nonsense variant in IQSEC2 is predicted to eliminate three functional domains. Consequently, these distinct variants found in four unrelated individuals with autism are likely indicative of loss-of-function mutations. CONCLUSIONS: In our two syndromic autism families, we discovered variants in two muscular dystrophy genes, DMD and CHKB. Given that DMD and CHKB are recognized for their participation in the non-cognitive manifestations of muscular dystrophy, it indicates that some genes transcend the boundary of apparently unrelated clinical categories, thereby establishing a novel connection between ASD and muscular dystrophy. Our findings also shed light on the complex inheritance patterns observed in Iranian consanguineous simplex families and emphasize the connection between autism spectrum disorder and muscular dystrophy. This underscores a likely genetic convergence between neurodevelopmental and neuromuscular disorders.

Humans

A Systematic Review of Help-Seeking Barriers for Racial-Ethnic Minority Caregivers Accessing Autism Diagnostic and Intervention Services.

Caregivers play an essential role in early help-seeking and intervention for children with Autism Spectrum Disorder (ASD). Caregivers, therefore, provide a crucial role in helping to address the racial and ethnic disparity identified in accessing ASD intervention and diagnostic services (Bejarano-Martín et al., Journal of Autism and Developmental Disorders 50(9), 3380-3394, 2020). Unfortunately, racial-ethnic minority caregivers of children with autism (CCA) are less likely to contact a physician or healthcare professionals about their concerns and more likely to delay their contact to have their child evaluated (Zeleke et al., Journal of Autism and Developmental Disorders 49(10), 4320-4331, 2019). However, little evidence exists to explain why such a gap exists in the help-seeking behaviors between White and racial-ethnic minority CCA. To address this knowledge gap, we conducted a systematic literature review to identify articles that have studied barriers in help-seeking for racial-ethnic minority CCA. A broad literature search across four databases was conducted (i.e., PubMed, PsycINFO, Education Resources Information Center, and Child Development and Adolescent Studies). The coding team identified 17 articles on help-seeking barriers for racial-ethnic minority CCA. A thematic analysis was used to narratively synthesize the help-seeking barriers identified across these 17 studies. Four themes emerged from our findings: logistical barriers, provider competence, ASD literacy, and cultural stigma. We also provided clinical recommendations for healthcare providers working with families with racial-ethnic minority CCA.

Humans

Autism care: reimagining the spectrum.

Autism care policy is at a critical inflection point. Applied behavior analysis (ABA), long established as the "gold standard" through state insurance mandates in the US, has functioned as the default reimbursable intervention for autistic children. However, advances in genomics, neuroscience, developmental psychology, and scholarship on autistic lived experience have expanded understanding of autism as a heterogeneous neurotype characterized by meaningful differences in neural organization rather than a unitary disorder. Contemporary models emphasize neurodiversity, strengths-based perspectives, and the interaction between developmental processes and environmental contexts in shaping functional outcomes. Many autistic children also meet criteria for complex care needs, requiring coordinated, interdisciplinary services across health, educational, and community systems. This manuscript proposes reframing the "autism spectrum" from a hierarchy of symptom severity to a prevention-oriented "spectrum of care." Adapting a public health taxonomy, interventions are organized into universal, selective, and indicated levels, targeting the prevention of avoidable disability, distress, and participation barriers. This model aligns autism services with whole-child, neurodiversity-affirming, and developmentally informed care, emphasizing relational health, autonomy, and life-course participation.

applied behavior analysis

A case of infantile autism associated with Down's syndrome.

There is increasing recognition that autism is a syndrome, not a disease entity. But it is not yet clear why some children develop autistic behavior more easily than others. It has been noted that autistic symptoms occur more frequently in children with mental retardation, blindness, congenital rubella, phenylketonuria, etc., and that there are very few cases of classical infantile autism in the general population. Very rarely has autism been associated with Down's syndrome. This is a report of a case of Down's syndrome and infantile autism.

Age Factors

Excitation/inhibition balance subtypes in autism and their genetic, neural, and clinical profiles.

Excitation (E)/inhibition (I) imbalance is considered a key mechanism in Autism Spectrum Disorder (ASD). However, E/I imbalance can have different etiologies with increased E relative to I (E&#x2009;>&#x2009;I) and increased I relative to E (E&#x2009;<&#x2009;I). Both neural profiles can be associated with altered clinical phenotype, suggesting "bell"-shape brain-behavior relationships. We derived E/I balance measures from resting-state EEG in a large sex-balanced sample of youths with and without autism (N&#x2009;=&#x2009;310; 164 youths with ASD and 146 typically developing (TD) youths) to address group discriminative power of neural markers, their relation to social skills, and the potential to define different neural subtypes within the autistic group. We also conducted genome-wide copy number variant (CNV) and gene expression analyses to provide additional insight into distinct neural subtypes in autism. A high-density 128-channel electroencephalography (EEG) was used to register neural activity of participants, blood samples were collected from the ASD youths to obtain genomic DNA, and rich behavioral phenotyping was provided for each participant. The results revealed three subgroups within the autistic cohort with the presence of "typical" E/I, E&#x2009;>&#x2009;I, and E&#x2009;<&#x2009;I neural profiles. The two subgroups with E/I imbalance had altered clinical phenotypes. In addition, these subgroups had different genetic profiles, showing that genes within identified CNVs had distinct expression patterns with the evidence of more prenatal (E&#x2009;<&#x2009;I) vs. postnatal (E&#x2009;>&#x2009;I) gene expression. The study suggests that the proposed clustering approach has relevance for the identification of clinically meaningful neural and genetic subtypes within a heterogeneous autistic cohort.

Autism spectrum disorder

Single-cell analysis of dup15q syndrome reveals developmental and postnatal molecular changes in autism.

Duplication 15q (dup15q) syndrome is a leading genetic cause of autism spectrum disorder, offering a key model for studying autism-related mechanisms. Using single-cell and single-nucleus RNA sequencing of cortical organoids from dup15q patient-derived iPSCs and post-mortem brain samples, we identify increased glycolysis, disrupted layer-specific marker expression, and aberrant morphology in deep-layer neurons during fetal-stage organoid development. In adolescent-adult postmortem brains, upper-layer neurons exhibit heightened transcriptional burden related to synaptic signaling, a pattern shared with idiopathic autism. Using spatial transcriptomics, we confirm these cell-type-specific disruptions in brain tissue. By gene co-expression network analysis, we reveal disease-associated modules that are well preserved between postmortem and organoid samples, suggesting metabolic dysregulation that may lead to altered neuron projection, synaptic dysfunction, and neuron hyperexcitability in dup15q syndrome.

Humans

Shielding the First 24 Postnatal Months of Life: A Proposal for a Prospective Cohort Study of Early-Life Electromagnetic Exposure and Autism Risk.

BACKGROUND: Autism Spectrum Disorder (ASD) involves Mirror Neuron System (MNS) dysfunction, driving core social and imitative impairments. Systemic physiological alterations such as autonomic dysregulation, mitochondrial dysfunction and neuroinflammation are known to impair synchronization and plasticity of neuronal clusters. A less-evident environmental cofactor, coinciding with rising ASD prevalence, is the considerable world-wide increase in electromagnetic radiation (EMR) overall exposure among children. Experimental evidence shows how low-intensity EMR influences cellular processes, via voltage-gated calcium channels (VGCCs), oxidative stress, and mitochondrial metabolism. The Resonant Convergence framework, allow to predict how chronic EMR exposure during the first 24 postnatal months of life can act as a factor in ASD pathogenesis. The best candidate mechanism is chronic Ion Cyclotron Resonance (ICR) detuning the Ca2+-calmodulin pathway, thus disrupting MNS synchronization. METHODS AND ANALYSIS: A prospective observational pilot cohort study (24-month follow-up) proposes to enroll 1000 full-term newborns into two arms: an EMR-reduced cohort (n = 500, rest and sleep-phase Faraday shielding) and a standard exposure cohort (n = 500). Exposure is quantified via radiofrequency (RF)/extremely low frequency(ELF) measurements, proximity analysis, device inventories and wearable dosimetry. The primary endpoint is a continuous neurodevelopmental trajectory score (joint attention, language, electroencephalogram (EEG) mu-rhythm); binary ASD diagnosis (Autism Diagnostic Observation Schedule, Second Edition (ADOS-2), Autism Diagnostic Interview-Revised (ADI-R)) is a secondary, exploratory endpoint. Moreover, an optional genomic screening will evaluate gene-environment interactions within extremely low-frequency electromagnetic field (ELF-EMF) vulnerable pathways, including ASD-associated genes upregulated by RF via bromodomain and extraterminal protein (BET)-mediated epigenetic mechanisms. Analyses will employ risk ratios, Fisher's exact tests and logistic regression adjusted for confounders; mixed-effects and Bayesian modeling will evaluate longitudinal outcomes and exposure reduction effects. Given a 2-3% baseline prevalence, approximately 20-30 ASD cases are expected. The study is therefore powered for exploratory signal detection rather than definitive causal inference, providing the critical baseline data required to justify and design future confirmatory trials. Sex-stratified modeling will address the 4:1 male-to-female prevalence ratio. ETHICS AND DISSEMINATION: Ethics committee approval is not yet sought; full protocol review and approval will be obtained prior to the study initiation, in strict accordance with the Declaration of Helsinki. Written parental informed consent will be mandatory for all participants prior to enrollment. Study findings and methodological milestones will be disseminated through peer-reviewed international scientific publications. This protocol provides a structured methodological framework for the first prospective investigation of sleep-phase EMR reduction as a potential modulator of ASD incidence during early neurodevelopment. Results will inform adequately powered confirmatory trials in electromagnetic neurodevelopmental epidemiology.

autism spectrum disorder

Follow-up report on autism in congenital rubella.

A longitudinal study was conducted of 243 children with congenital rubella. In this sample a high rate of autism and a high rate of recovery were observed. Examination of the data suggested that the rubella virus was the primary etiologic agent. It is hypothesized that the course of autism was that of a chronic infection in which recovery, chronicity, improvement, worsening, and delayed appearance of the autistic syndrome all were found. Other rubella consequences such as blindness, deafness, and cardiac and neuromuscular defects remained present except as modified by operations and prostheses. Degree of mental retardation initially was related to the outcome of autism but shifts in mental retardation over time did not correlate significantly for the group with shift in the autistic symptoms.

Autistic Disorder

Histidinemia and infantile autism.

A 10-year-old boy first showed features of infantile autism at age 24 months. Histidinemia was also diagnosed, with histidine blood levels seven times higher than the upper normal values. If the coexistence of autism and histidinemia was not coincidental, histidinemia may have constituted a necessary but not sufficient factor leading to the clinical condition of autism. Other members of the patient's family had high blood levels of histidine, but did not show symptoms that have been related to histidinemia.

Amino Acid Metabolism, Inborn Errors

Infantile autism. I: A prospective study of the diagnosis.

A prospective study was made of 200 consecutive children to evaluate the usefulness in the diagnosis of infantile autism of the behavioral scale reported by Clancy and coworkers in 1969. On this scale seven or more of 14 behavioral manifestations must be present before a diagnosis of autism can be made. Using this scale alone, 48 of the 200 children studied were "scale positive", i.e. could be considered autistic. However, further study of this group showed that only one child fulfilled the classical criteria of Kanner (1943) for a diagnosis of early infantile autism. Scale "positivity" was found to correlate with mental retardation and to be associated with other developmental defects, especially learning disorders and hearing loss.

Adolescent