1. Chadman KK, Guariglia SR, Yoo JH. {{New directions in the treatment of autism spectrum disorders from animal model research}}. {Expert Opin Drug Discov};2012 (Apr 12)
Introduction: Currently, there is not an effective pharmacotherapy for the core symptoms of the autism spectrum disorders (ASD), which include aberrant social behavior, delayed communication and repetitive behavior and/or restricted interests. There are several drugs that treat the symptoms associated with autism including irritability, aggressiveness and hyperactivity. Current drug research is based on the ongoing genetic, animal model and neuropathologic research. Two areas in particular, the glutamate and oxytocin systems, provide exciting new avenues for drug discovery. Areas covered: This review examines what approaches have been used for the drugs that are currently being used to treat people with ASD. For the most part, drugs that treat other neuropsychiatric disorders have been examined to treat the people with ASD, unfortunately with little effect on the core symptoms. Expert Opinion: Until recently, there was not a plethora of knowledge about the neurobiological substrates of social behavior, pragmatic language usage and repetitive and/or restricted behaviors. Therefore, drug discovery has used the tools available for other neuropsychiatric disorders. Now that more biological information is available, there are many avenues for research for drug targets for ASD.
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2. Elsabbagh M, Divan G, Koh YJ, Kim YS, Kauchali S, Marcin C, Montiel-Nava C, Patel V, Paula CS, Wang C, Yasamy MT, Fombonne E. {{Global Prevalence of Autism and Other Pervasive Developmental Disorders}}. {Autism Res};2012 (Apr 11)
We provide a systematic review of epidemiological surveys of autistic disorder and pervasive developmental disorders (PDDs) worldwide. A secondary aim was to consider the possible impact of geographic, cultural/ethnic, and socioeconomic factors on prevalence estimates and on clinical presentation of PDD. Based on the evidence reviewed, the median of prevalence estimates of autism spectrum disorders was 62/10 000. While existing estimates are variable, the evidence reviewed does not support differences in PDD prevalence by geographic region nor of a strong impact of ethnic/cultural or socioeconomic factors. However, power to detect such effects is seriously limited in existing data sets, particularly in low-income countries. While it is clear that prevalence estimates have increased over time and these vary in different neighboring and distant regions, these findings most likely represent broadening of the diagnostic concets, diagnostic switching from other developmental disabilities to PDD, service availability, and awareness of autistic spectrum disorders in both the lay and professional public. The lack of evidence from the majority of the world’s population suggests a critical need for further research and capacity building in low- and middle-income countries. Autism Res 2012, **: **-**. (c) 2012 International Society for Autism Research, Wiley Periodicals, Inc.
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3. Keehn B, Shih P, Brenner LA, Townsend J, Muller RA. {{Functional connectivity for an « Island of sparing » in autism spectrum disorder: An fMRI study of visual search}}. {Hum Brain Mapp};2012 (Apr 12)
Although autism is usually characterized with respect to sociocommunicative impairments, visual search is known as a domain of relative performance strength in this disorder. This study used functional MRI during visual search in children with autism spectrum disorder (n = 19; mean age = 13;10) and matched typically developing children (n = 19; mean age = 14;0). We selected regions of interest within two attentional networks known to play a crucial role in visual search processes, such as goal-directed selective attention, filtering of irrelevant distractors, and detection of behaviorally-relevant information, and examined activation and connectivity within and between these attentional networks. Additionally, based on prior research suggesting links between visual search abilities and autism symptomatology, we tested for correlations between sociocommunicative impairments and behavioral and neural indices of search. Contrary to many previous functional connectivity magnetic resonance imaging studies of autism that reported functional underconnectivity for task domains of weakness, we found atypically increased connectivity within and between attentional networks in autism. Additionally, we found increased functional connectivity for occipital regions, both locally and for long-distance connections with frontal regions. Both behavioral and neural indices of search were correlated with sociocommunicative impairment in children with autism. This association suggests that strengths in nonsocial visuospatial processing may be related to the development of core autistic sociocommunicative impairments. Hum Brain Mapp , 2012. (c) 2012 Wiley Periodicals, Inc.
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4. Neale BM, Kou Y, Liu L, Ma’ayan A, Samocha KE, Sabo A, Lin CF, Stevens C, Wang LS, Makarov V, Polak P, Yoon S, Maguire J, Crawford EL, Campbell NG, Geller ET, Valladares O, Schafer C, Liu H, Zhao T, Cai G, Lihm J, Dannenfelser R, Jabado O, Peralta Z, Nagaswamy U, Muzny D, Reid JG, Newsham I, Wu Y, Lewis L, Han Y, Voight BF, Lim E, Rossin E, Kirby A, Flannick J, Fromer M, Shakir K, Fennell T, Garimella K, Banks E, Poplin R, Gabriel S, Depristo M, Wimbish JR, Boone BE, Levy SE, Betancur C, Sunyaev S, Boerwinkle E, Buxbaum JD, Cook EH, Devlin B, Gibbs RA, Roeder K, Schellenberg GD, Sutcliffe JS, Daly MJ. {{Patterns and rates of exonic de novo mutations in autism spectrum disorders}}. {Nature};2012 (Apr 4)
Autism spectrum disorders (ASD) are believed to have genetic and environmental origins, yet in only a modest fraction of individuals can specific causes be identified. To identify further genetic risk factors, here we assess the role of de novo mutations in ASD by sequencing the exomes of ASD cases and their parents (n = 175 trios). Fewer than half of the cases (46.3%) carry a missense or nonsense de novo variant, and the overall rate of mutation is only modestly higher than the expected rate. In contrast, the proteins encoded by genes that harboured de novo missense or nonsense mutations showed a higher degree of connectivity among themselves and to previous ASD genes as indexed by protein-protein interaction screens. The small increase in the rate of de novo events, when taken together with the protein interaction results, are consistent with an important but limited role for de novo point mutations in ASD, similar to that documented for de novo copy number variants. Genetic models incorporating these data indicate that most of the observed de novo events are unconnected to ASD; those that do confer risk are distributed across many genes and are incompletely penetrant (that is, not necessarily sufficient for disease). Our results support polygenic models in which spontaneous coding mutations in any of a large number of genes increases risk by 5- to 20-fold. Despite the challenge posed by such models, results from de novo events and a large parallel case-control study provide strong evidence in favour of CHD8 and KATNAL2 as genuine autism risk factors.
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5. Ollington N, Green VA, O’Reilly MF, Lancioni GE, Didden R. {{Functional analysis of insistence on sameness in an 11-year old boy with Asperger syndrome}}. {Dev Neurorehabil};2012;15(2):154-159.
Objective: To identify the functional properties of insistence on sameness associated with autism spectrum disorders. Method: An 11-year-old boy with Asperger syndrome was observed during play where scenarios (mistakes, misplaced items, interrupted activity) were created to correspond with parent-reported scenarios where the child would insist on sameness. The extent of problem behaviour was observed under four functional assessment conditions (restore environment, tangible, attention, escape), according to a multi-element design. Results: The results showed an interaction between the scenario type and type of functional assessment condition. Problem behaviour appeared to have a restorative function related to correcting a mistake, an attention function related to attempting to recruit help in finding a missing item and a tangible function suggesting an attempt to regain access to the materials and activity. Conclusion: Problem behaviours related to insistence on sameness may be motivated by different consequences depending on the scenario created.
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6. O’Roak BJ, Vives L, Girirajan S, Karakoc E, Krumm N, Coe BP, Levy R, Ko A, Lee C, Smith JD, Turner EH, Stanaway IB, Vernot B, Malig M, Baker C, Reilly B, Akey JM, Borenstein E, Rieder MJ, Nickerson DA, Bernier R, Shendure J, Eichler EE. {{Sporadic autism exomes reveal a highly interconnected protein network of de novo mutations}}. {Nature};2012 (Apr 4)
It is well established that autism spectrum disorders (ASD) have a strong genetic component; however, for at least 70% of cases, the underlying genetic cause is unknown. Under the hypothesis that de novo mutations underlie a substantial fraction of the risk for developing ASD in families with no previous history of ASD or related phenotypes-so-called sporadic or simplex families-we sequenced all coding regions of the genome (the exome) for parent-child trios exhibiting sporadic ASD, including 189 new trios and 20 that were previously reported. Additionally, we also sequenced the exomes of 50 unaffected siblings corresponding to these new (n = 31) and previously reported trios (n = 19), for a total of 677 individual exomes from 209 families. Here we show that de novo point mutations are overwhelmingly paternal in origin (4:1 bias) and positively correlated with paternal age, consistent with the modest increased risk for children of older fathers to develop ASD. Moreover, 39% (49 of 126) of the most severe or disruptive de novo mutations map to a highly interconnected beta-catenin/chromatin remodelling protein network ranked significantly for autism candidate genes. In proband exomes, recurrent protein-altering mutations were observed in two genes: CHD8 and NTNG1. Mutation screening of six candidate genes in 1,703 ASD probands identified additional de novo, protein-altering mutations in GRIN2B, LAMC3 and SCN1A. Combined with copy number variant (CNV) data, these results indicate extreme locus heterogeneity but also provide a target for future discovery, diagnostics and therapeutics.
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7. Ramdoss S, Machalicek W, Rispoli M, Mulloy A, Lang R, O’Reilly M. {{Computer-based interventions to improve social and emotional skills in individuals with autism spectrum disorders: A systematic review}}. {Dev Neurorehabil};2012;15(2):119-135.
Objective: To review studies involving the use of computer-based interventions (CBI) to improve the social and emotional skills (e.g. emotional recognition) of individuals with autism spectrum disorders (ASD). Methods: The use of computer-based intervention (CBI) in the treatment of autism spectrum disorders (ASD) may offer some advantages to traditional one-to-one or group instruction including easier differentiation of instruction, decreased distractions and the incorporation of an individual’s relative visual learning strengths. However, the results of past research suggest varying outcomes for CBI with individuals with ASD. This review provides a systematic analysis of studies investigating CBI to improve social and emotional skills (e.g. emotion recognition) of individuals with ASD. Electronic database searches and ancestral searches were used to identify studies that met pre-determined inclusion criteria. The included studies were then summarized in terms of: (a) participant characteristics, (b) social and emotional skills targeted, (c) details of the CBI, (d) results, and (e) certainty of evidence. Results: The results of these studies indicated that CBI’s effect on social and emotional skills was mixed, with the majority of studies reporting unacceptable outcomes following intervention. Conclusions: Overall, this review suggests that the use of CBI to improve the social and emotional skills of individuals with ASD is a promising practice. A comparison of CBI plus tutoring and face-to-face social skills training suggests that CBI can be as effective as face-to-face instruction. Practitioners should carefully consider the preferences and existing abilities of individuals with ASD and the customizability of the software when deciding to use CBI and selecting a software program.
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8. Sanders SJ, Murtha MT, Gupta AR, Murdoch JD, Raubeson MJ, Willsey AJ, Ercan-Sencicek AG, Dilullo NM, Parikshak NN, Stein JL, Walker MF, Ober GT, Teran NA, Song Y, El-Fishawy P, Murtha RC, Choi M, Overton JD, Bjornson RD, Carriero NJ, Meyer KA, Bilguvar K, Mane SM, Sestan N, Lifton RP, Gunel M, Roeder K, Geschwind DH, Devlin B, State MW. {{De novo mutations revealed by whole-exome sequencing are strongly associated with autism}}. {Nature};2012 (Apr 4)
Multiple studies have confirmed the contribution of rare de novo copy number variations to the risk for autism spectrum disorders. But whereas de novo single nucleotide variants have been identified in affected individuals, their contribution to risk has yet to be clarified. Specifically, the frequency and distribution of these mutations have not been well characterized in matched unaffected controls, and such data are vital to the interpretation of de novo coding mutations observed in probands. Here we show, using whole-exome sequencing of 928 individuals, including 200 phenotypically discordant sibling pairs, that highly disruptive (nonsense and splice-site) de novo mutations in brain-expressed genes are associated with autism spectrum disorders and carry large effects. On the basis of mutation rates in unaffected individuals, we demonstrate that multiple independent de novo single nucleotide variants in the same gene among unrelated probands reliably identifies risk alleles, providing a clear path forward for gene discovery. Among a total of 279 identified de novo coding mutations, there is a single instance in probands, and none in siblings, in which two independent nonsense variants disrupt the same gene, SCN2A (sodium channel, voltage-gated, type II, alpha subunit), a result that is highly unlikely by chance.
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9. Siniscalco D, Sapone A, Cirillo A, Giordano C, Maione S, Antonucci N. {{Autism spectrum disorders: is mesenchymal stem cell personalized therapy the future?}}. {J Biomed Biotechnol};2012;2012:480289.
Autism and autism spectrum disorders (ASDs) are heterogeneous neurodevelopmental disorders. They are enigmatic conditions that have their origins in the interaction of genes and environmental factors. ASDs are characterized by dysfunctions in social interaction and communication skills, in addition to repetitive and stereotypic verbal and nonverbal behaviours. Immune dysfunction has been confirmed with autistic children. There are no defined mechanisms of pathogenesis or curative therapy presently available. Indeed, ASDs are still untreatable. Available treatments for autism can be divided into behavioural, nutritional, and medical approaches, although no defined standard approach exists. Nowadays, stem cell therapy represents the great promise for the future of molecular medicine. Among the stem cell population, mesenchymal stem cells (MSCs) show probably best potential good results in medical research. Due to the particular immune and neural dysregulation observed in ASDs, mesenchymal stem cell transplantation could offer a unique tool to provide better resolution for this disease.
