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Autism’s etiology is heterogeneous. It derives generically from a complex of interactions between genetic, epigenetic and environmental factors. Chromosomal rearrangements at almost all chromosomes have been reported among individuals with autism spectrum disorders (ASD). In this report, we represent three autistic patients with chromosomal abnormalities at 10q and 22q with an interesting case of 10q duplication rather than deletion. This report explores the contribution of the affected genomic regions to ASD. It may contribute to the field of research categorizing candidate loci for ASD, which would be useful in genotype– phenotype analyses for ASD.

Background The aim of the present study was to determine the type and percentage of referral situations, risk factors, associated syndromes, and parental awareness of autism spectrum disorder (ASD) children who visited the Medical Research Centre of Excellence, National Research Centre in Cairo, specialized in ASD diagnosis and management. Methods The study included 530 children who were diagnosed with ASD. For those, full medical history, clinical examination, severity evaluation, and testing the language and cognitive development were performed. The process of diagnosis and assessment of parents’ awareness and knowledge about ASD was investigated using questionnaires. Results The clinic was mainly visited by self-referral. About half of the participants (51.4 %) had previously visited other doctors (1–5 physicians) who were mostly pediatricians. The parents’ awareness was mostly limited to the term “autism”, but not the nature of ASD. Caesarean section was the most common risk factor (57.4 %), followed by jaundice (30.1 %). The most common presenting symptoms were language (81.5 %) and social (60.4 %) deficits. ASD severity was found to be high in association with attention deficit hyperactivity disorder (ADHD) and electroencephalogram (EEG) changes (p = 0.001). Conclusion The risk factors and associated syndromes in the Egyptian population studied were similar to those reported in previous studies performed in other populations, but their percentage was different. Perinatal problems were the most common risk factors, which may relate to the influence of gene-environmental interaction on the factors which could play a role in developing ASD or increasing its severity. The process of ASD diagnosis was commonly delayed among the participants. Increasing awareness and knowledge among health care professionals and parents is urgently needed to facilitate early diagnosis and intervention services, which will lead to improvement of the developmental outcomes for ASD children. The associated syndromes could be the driving force to seek medical advice and could influence the ASD severity.

Background Current estimates indicate that >80 % of children with autism spectrum disorder (ASD) exhibit concomitant sensory processing problems and hyper- or hypo-reactivity to sensory input. These are now included as diagnostic criteria for ASD in the Diagnostic and Statistical Manual of Mental Disorders—Fifth Edition. Chromosomal rearrangements, copy number variations (CNVs), and coding sequence variants involving >100 genes have been identified in patients with ASD. Studying the CNVs of one such gene, SHANK3, and the associated phenotype in patients with ASD could provide insights that will guide future ASD treatments and interventions. Objective To assess SHANK3 CNVs in children with ASD and investigate their sensory processing patterns using the Short Sensory Profile (SSP). Subjects and methods Forty children with ASD were assessed using the Autism Diagnostic Interview-Revised. SSP was used to evaluate atypical sensory behavior, e.g., hyper- or hypo-reactivity to sensory input or unusual sensory interests. SHANK3 CNVs were assessed in these children using Multiplex Ligation-dependent Probe Amplification. Results Of the 40 cases, 77.5 % showed sensory reactivity symptoms. The greatest difference from normality was observed in the under-responsive/seeks sensation domain, followed by the tactile sensitivity domain, whereas hypo-activity (low-energy/weak domain) was closest to normal. The sensory reactivity symptoms were significantly correlated with the severity of ASD. However, only three of the 40 cases had de novo duplications at 22q13.33. The duplications included SHANK3 in two of the cases and only the distal flanking region of SHANK3 in the third case. All three duplication cases also showed symptoms associated with the low-energy/weak domain. Conclusion We found that children with ASD exhibited sensory processing problems. The SHANK3 copy number gains found demonstrate the gene dosage effect of SHANK3 in ASD pathogenesis. This study adds to the growing understanding of 22q13 duplications that include SHANK3.

The autism phenotype is associated with an excess of brain volume due in part to decreased pruning during development. Here we aimed at assessing brain volume early in development to further elucidate previous findings in autism and determine whether this pattern is restricted to idiopathic autism or shared within the autistic phenotype (fragile X syndrome [FXS]). We investigated brain volume in 37 participants, using the fully automated Civet pipeline anatomical magnetic resonance imaging. 3 groups with intellectual deficiency: autism (AUT); its most associated FXS; and its most opposite Williams syndrome (WS) were compared with each other and with normal controls (NC). We report increased total and regional gray and white matter brain volume in AUT and FXS relative to WS and NC. These findings are discussed in light of the possibilities leading for the enlarged brain volume in children with the AUT phenotype. We speculate that this excess suggests reduced regression of neuronal processes “pruning” in cortical and subcortical regions in AUT/FXS, which may be due to a mutation in specific genes involved in pruning and/or a lack of socio-emotional environmental experience during a critical developmental period.