1. Al-Ansari AM, Ahmed MM. {{Parental age. Risk of autistic disorder}}. {Neurosciences (Riyadh)};2012 (Oct);17(4):382-383.
2. Andersson GW, Gillberg C, Miniscalco C. {{Pre-school children with suspected autism spectrum disorders: Do girls and boys have the same profiles?}}. {Res Dev Disabil};2012 (Sep 25);34(1):413-422.
The male to female ratio is raised in autism spectrum disorders (ASD). Previous studies have suggested that girls with ASD have more problems with communication than boys, but boys show more repetitive behaviours than girls. In this study, 20 girls, 1.8-3.9 years of age were matched for chronological and developmental age with 20 boys with suspected ASD. All the children were recruited after population screening and referral by Child Health Care Services to a specialised neuropsychiatry clinic, where they underwent comprehensive neuropsychiatric assessments. Comparisons were made with regard to diagnosis, developmental profiles and global disability. No significant gender differences were found. There were strong correlations between results obtained in different developmental areas. The results suggest that either (1) previous studies finding clear gender differences may have overrated discrepancies between girls and boys in ASD, or that (2) there may be girls, who will not be identified in the early years with our current screening instruments. More research with a much larger population representative study samples is required.
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3. Anitha A, Thanseem I, Nakamura K, Yamada K, Iwayama Y, Toyota T, Iwata Y, Suzuki K, Sugiyama T, Tsujii M, Yoshikawa T, Mori N. {{Protocadherin alpha (PCDHA) as a novel susceptibility gene for autism}}. {J Psychiatry Neurosci};2012 (Oct 2);37(6):120058.
Background: Synaptic dysfunction has been shown to be involved in the pathogenesis of autism. We hypothesized that the protocadherin alpha gene cluster (PCDHA), which is involved in synaptic specificity and in serotonergic innervation of the brain, could be a suitable candidate gene for autism. Methods: We examined 14 PCDHA single nucleotide polymorphisms (SNPs) for genetic association with autism in DNA samples of 3211 individuals (841 families, including 574 multiplex families) obtained from the Autism Genetic Resource Exchange. Results: Five SNPs (rs251379, rs1119032, rs17119271, rs155806 and rs17119346) showed significant associations with autism. The strongest association (p < 0.001) was observed for rs1119032 (z score of risk allele G = 3.415) in multiplex families; SNP associations withstand multiple testing correction in multiplex families (p = 0.041). Haplotypes involving rs1119032 showed very strong associations with autism, withstanding multiple testing corrections. In quantitative transmission disequilibrium testing of multiplex fam – ilies, the G allele of rs1119032 showed a significant association (p = 0.033) with scores on the Autism Diagnostic Interview-Revised (ADI-R)_D (early developmental abnormalities). We also found a significant difference in the distribution of ADI-R_A (social interaction) scores between the A/A, A/G and G/G genotypes of rs17119346 (p = 0.002). Limitations: Our results should be replicated in an in – dependent population and/or in samples of different racial backgrounds. Conclusion: Our study provides strong genetic evidence of PCDHA as a potential candidate gene for autism.
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4. Burrus CJ. {{A biochemical rationale for the interaction between gastrointestinal yeast and autism}}. {Med Hypotheses};2012 (Sep 26)
Autism is a disorder characterized by difficulty with social interactions, difficulty expressing empathy and intimacy and, in many cases, mild to severe language and learning deficits. Current estimates suggest autism now affects approximately one in 88 children, with rates increasing rapidly, making autism one of the most common and devastating developmental disorders. This trend is especially alarming considering that a cause for this disorder has yet to be discovered, nor are there successful biological treatments. Here a possible biochemical etiology is proposed for a certain spectrum of autism based on a reaction between propionic acid and ammonia released by Candida albicans in the gastrointestinal tract. A reaction between ammonia and propionic acid should result in the production of beta-alanine, a chemical similar in composition to gamma-aminobutyric acid (GABA), an inhibitory neurotransmitter which has been shown to be present in higher quantities in autistic patients. Assuming beta-alanine is able to cross the blood-brain barrier, beta-alanine would be used in the brain as a partial antagonist, blocking the receptor sites for GABA, thus facilitating the production of more GABA to achieve equilibrium. An excess of GABA has been proposed as a possible contributor to autism. Further research should be conducted with this hypothesis to determine whether the chemical reaction in the human body between propionic acid and ammonia does in fact produce a chemical structurally and functionally similar to beta-alanine, as well as how this product affects the brain. Positive conclusions from this follow-on research could result in a preventative screening test for sensitivity to propionic acid and gastrointestinal yeast, thus slowing the progression of this type of autism. A more targeted treatment for children already diagnosed with autism could also result.
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5. Gadow KD. {{Schizophrenia spectrum and attention-deficit/hyperactivity disorder symptoms in autism spectrum disorder and controls}}. {J Am Acad Child Adolesc Psychiatry};2012 (Oct);51(10):1076-1084.
OBJECTIVE: This study compared the differential severity of specific symptoms of schizophrenia spectrum disorder (SSD) in children with autism spectrum disorder (ASD) and child psychiatry outpatient referrals (controls). Each group was further subdivided into subgroups with and without co-occurring attention-deficit/hyperactivity disorder (ADHD). METHOD: Children with ASD (n = 147) and controls (n = 335) were evaluated with parent and teacher versions of a psychometrically established DSM-IV-referenced rating scale. RESULTS: The two ASD groups (with and without ADHD) had a larger number of more severe SSD symptoms than their respective control groups (with and without ADHD), extending the observation of an association between ASD and SSD to subgroups with and without co-occurring ADHD. The ASD groups exhibited more severe schizoid personality symptoms than controls, but findings for schizophrenia symptoms were mixed. The ASD + ADHD group generally had more severe disorganized thought, disorganized behavior, and negative schizophrenia symptoms than controls (with and without ADHD); nevertheless, findings varied according to ADHD status (present versus absent), individual symptom (symptom specificity), and informant (informant specificity). Ratings of hallucinations and delusions indicated mild severity and few group differences. Negative symptoms such as inappropriate emotional reactions evidenced considerable group divergence. CONCLUSION: Findings provide additional support for an interrelation between ASD and SSD symptoms and the differential influence of neurobehavioral syndromes on co-occurring symptom severity, underscore the multidimensionality of SSD in children with ASD, and suggest how symptom phenotypes may contribute to a better understanding of the etiology, nosology, and possibly clinical management.
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6. Hani HB, Gonzalez-Barrero AM, Nadig AS. {{Children’s referential understanding of novel words and parent labeling behaviors: similarities across children with and without autism spectrum disorders}}. {J Child Lang};2012 (Oct 1):1-32.
ABSTRACT This study examined two facets of the use of social cues for early word learning in parent-child dyads, where children had an Autism Spectrum Disorder (ASD) or were typically developing. In Experiment 1, we investigated word learning and generalization by children with ASD (age range: 3;01-6;02) and typically developing children (age range: 1;02-4;09) who were matched on language ability. In Experiment 2, we examined verbal and non-verbal parental labeling behaviors. First, we found that both groups were similarly able to learn a novel label using social cues alone, and to generalize this label to other representations of the object. Children who utilized social cues for word learning had higher language levels. Second, we found that parental cues used to introduce object labels were strikingly similar across groups. Moreover, parents in both groups adapted labeling behavior to their child’s language level, though this surfaced in different ways across groups.
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7. Hock R, Ahmedani BK. {{Parent perceptions of autism severity: Exploring the social ecological context}}. {Disabil Health J};2012 (Oct);5(4):298-304.
BACKGROUND: Health professionals incorporate parent reports into the diagnosis and treatment of children with an autism spectrum disorder (ASD). Yet little is known about the contextual forces that may shape parents’ perceptions of their child. OBJECTIVES: The current study seeks to: 1) compare the social ecological contexts of parents of children with ASD and parents of non-autistic children, and 2) explore the social ecological influences on parents’ perception of their child’s ASD severity. METHODS: This study employed a cross-sectional analysis of data from the 2007-2008 National Survey of Children’s Health (NSCH) in the United States. Social ecological factors of interest included variables depicting family physical environment, family social environment, and individual parent characteristics. RESULTS: Results indicate that parents of children with ASD had increased odds of reporting poor neighborhood social capital, greater aggravation, more difficulty coping, and lower levels of relationship satisfaction and mental health. Parents’ perceptions of their child’s ASD severity were associated with several factors of their social ecological context. More severe parent-reported ASD was associated with aspects of the physical environment (rundown housing and garbage on the street), the social environment (parent relationship satisfaction) and individual parent characteristics (parent aggravation and mental health). CONCLUSIONS: Results suggest ways that professionals can contextualize parent reports to aid in the diagnosis and treatment of children with ASD. Findings also highlight a need for longitudinal research using well-characterized measures to determine the nature and direction of relationships between contextual factors and parents’ perceptions.
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8. Kennedy DP, Adolphs R. {{Perception of emotions from facial expressions in high-functioning adults with autism}}. {Neuropsychologia};2012 (Sep 27)
Impairment in social communication is one of the diagnostic hallmarks of autism spectrum disorders, and a large body of research has documented aspects of impaired social cognition in autism, both at the level of the processes and the neural structures involved. Yet one of the most common social communicative abilities in everyday life, the ability to judge somebody’s emotion from their facial expression, has yielded conflicting findings. To investigate this issue, we used a sensitive task that has been used to assess facial emotion perception in a number of neurological and psychiatric populations. Fifteen high-functioning adults with autism and 19 control participants rated the emotional intensity of 36 faces displaying basic emotions. Every face was rated 6 times-once for each emotion category. The autism group gave ratings that were significantly less sensitive to a given emotion, and less reliable across repeated testing, resulting in overall decreased specificity in emotion perception. We thus demonstrate a subtle but specific pattern of impairments in facial emotion perception in people with autism.
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9. Rogers SJ, Estes A, Lord C, Vismara L, Winter J, Fitzpatrick A, Guo M, Dawson G. {{Effects of a Brief Early Start Denver Model (ESDM)-Based Parent Intervention on Toddlers at Risk for Autism Spectrum Disorders: A Randomized Controlled Trial}}. {J Am Acad Child Adolesc Psychiatry};2012 (Oct);51(10):1052-1065.
OBJECTIVE: This study was carried out to examine the efficacy of a 12-week, low-intensity (1-hour/wk of therapist contact), parent-delivered intervention for toddlers at risk for autism spectrum disorders (ASD) aged 14 to 24 months and their families. METHOD: A randomized controlled trial involving 98 children and families was carried out in three different sites investigating the efficacy of a parent delivery of the Early Start Denver Model (P-ESDM), which fosters parental use of a child-centered responsive interaction style that embeds many teaching opportunities into play, compared to community treatment as usual. Assessments were completed at baseline and 12 weeks later, immediately after the end of parent coaching sessions. RESULTS: There was no effect of group assignment on parent-child interaction characteristics or on any child outcomes. Both groups of parents improved interaction skills, and both groups of children demonstrated progress. Parents receiving P-ESDM demonstrated significantly stronger working alliances with their therapists than did the community group. Children in the community group received significantly more intervention hours than those in the P-ESDM group. For the group as a whole, both younger child age at the start of intervention and a greater number of intervention hours were positively related to the degree of improvement in children’s behavior for most variables. CONCLUSIONS: Parent-implemented intervention studies for early ASD thus far have not demonstrated the large effects seen in intensive-treatment studies. Evidence that both younger age and more intervention hours positively affect developmental rates has implications for clinical practice, service delivery, and public policy.
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10. Steinberg KM, Ramachandran D, Patel V, Shetty AC, Cutler DJ, Zwick ME. {{Identification of rare X-linked neuroligin variants by massively parallel sequencing in males with autism spectrum disorder}}. {Mol Autism};2012 (Sep 28);3(1):8.
ABSTRACT: BACKGROUND: Autism spectrum disorder (ASD) is highly heritable, but the genetic risk factors for it remain largely unknown. Although structural variants with large effect sizes may explain up to 15% ASD, genome-wide association studies have failed to uncover common single nucleotide variants with large effects on phenotype. The focus within ASD genetics is now shifting to the examination of rare sequence variants of modest effect, which is most often achieved via exome selection and sequencing. This strategy has indeed identified some rare candidate variants; however, the approach does not capture the full spectrum of genetic variation that might contribute to the phenotype. METHODS: We surveyed two loci with known rare variants that contribute to ASD, the X-linked neuroligin genes by performing massively parallel Illumina sequencing of the coding and noncoding regions from these genes in males from families with multiplex autism. We annotated all variant sites and functionally tested a subset to identify other rare mutations contributing to ASD susceptibility. RESULTS: We found seven rare variants at evolutionary conserved sites in our study population. Functional analyses of the three 3′ UTR variants did not show statistically significant effects on the expression of NLGN3 and NLGN4X. In addition, we identified two NLGN3 intronic variants located within conserved transcription factor binding sites that could potentially affect gene regulation. CONCLUSIONS: These data demonstrate the power of massively parallel, targeted sequencing studies of affected individuals for identifying rare, potentially disease-contributing variation. However, they also point out the challenges and limitations of current methods of direct functional testing of rare variants and the difficulties of identifying alleles with modest effects.
