1. {{The role of genetic factors in autism risk may have been exaggerated in some studies}}. {Nurs Stand};2014 (May 28);28(39):16-17.
The largest population-based study to date investigating the familial risk of autism has found that about 50 per cent of the risk that a child will develop autism is caused by genetic factors – considerably lower than the 90 per cent reported in earlier twin studies.
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2. Anitha A, Thanseem I, Nakamura K, Vasu MM, Yamada K, Ueki T, Iwayama Y, Toyota T, Tsuchiya KJ, Iwata Y, Suzuki K, Sugiyama T, Tsujii M, Yoshikawa T, Mori N. {{Zinc finger protein 804A () and verbal deficits in individuals with autism}}. {J Psychiatry Neurosci};2014 (Jul 1);39(4):130126.
BACKGROUND: In a genome-wide association study of autism, zinc finger protein 804A (ZNF804A) single nucleotide polymorphisms (SNPs) were found to be nominally associated in verbally deficient individuals with autism. Zinc finger protein 804A copy number variations (CNVs) have also been observed in individuals with autism. In addition, ZNF804A is known to be involved in theory of mind (ToM) tasks, and ToM deficits are deemed responsible for the communication and social challenges faced by individuals with autism. We hypothesized that ZNF804A could be a risk gene for autism. METHODS: We examined the genetic association and CNVs of ZNF804A in 841 families in which 1 or more members had autism. We compared the expression of ZNF804A in the postmortem brains of individuals with autism (n = 8) and controls (n = 13). We also assessed in vitro the effect of ZNF804A silencing on the expression of several genes known to be involved in verbal efficiency and social cognition. RESULTS: We found that rs7603001 was nominally associated with autism (p = 0.018). The association was stronger (p = 0.008) in the families of individuals with autism who were verbally deficient (n = 761 families). We observed ZNF804A CNVs in 7 verbally deficient boys with autism. In ZNF804A knockdown cells, the expression of synaptosomal-associated protein, 25kDa (SNAP25) was reduced compared with controls (p = 0.009). The expression of ZNF804A (p = 0.009) and SNAP25 (p = 0.009) were reduced in the anterior cingulate gyrus (ACG) of individuals with autism. There was a strong positive correlation between the expression of ZNF804A and SNAP25 in the ACG (p < 0.001). LIMITATIONS: Study limitations include our small sample size of postmortem brains. CONCLUSION: Our results suggest that ZNF804A could be a potential candidate gene mediating the intermediate phenotypes associated with verbal traits in individuals with autism.
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3. Bennett TA, Szatmari P, Georgiades K, Hanna S, Janus M, Georgiades S, Duku E, Bryson S, Fombonne E, Smith IM, Mirenda P, Volden J, Waddell C, Roberts W, Vaillancourt T, Zwaigenbaum L, Elsabbagh M, Thompson A. {{Language Impairment and Early Social Competence in Preschoolers with Autism Spectrum Disorders: A Comparison of DSM-5 Profiles}}. {J Autism Dev Disord};2014 (May 28)
Children with autism spectrum disorder (ASD) and structural language impairment (LI) may be at risk of more adverse social-developmental outcomes. We examined trajectories of early social competence (using the Vineland-II) in 330 children aged 2-4 years recently diagnosed with ASD, and compared 3 subgroups classified by: language impairment (ASD/LI); intellectual disability (ASD/ID) and ASD without LI or ID (ASD/alone). Children with ASD/LI were significantly more socially impaired at baseline than the ASD/alone subgroup, and less impaired than those with ASD/ID. Growth in social competence was significantly slower for the ASD/ID group. Many preschool-aged children with ASD/LI at time of diagnosis resembled « late talkers » who appeared to catch up linguistically. Children with ASD/ID were more severely impaired and continued to lag further behind.
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4. Berko ER, Suzuki M, Beren F, Lemetre C, Alaimo CM, Calder RB, Ballaban-Gil K, Gounder B, Kampf K, Kirschen J, Maqbool SB, Momin Z, Reynolds DM, Russo N, Shulman L, Stasiek E, Tozour J, Valicenti-McDermott M, Wang S, Abrahams BS, Hargitai J, Inbar D, Zhang Z, Buxbaum JD, Molholm S, Foxe JJ, Marion RW, Auton A, Greally JM. {{Mosaic epigenetic dysregulation of ectodermal cells in autism spectrum disorder}}. {PLoS Genet};2014 (May);10(5):e1004402.
DNA mutational events are increasingly being identified in autism spectrum disorder (ASD), but the potential additional role of dysregulation of the epigenome in the pathogenesis of the condition remains unclear. The epigenome is of interest as a possible mediator of environmental effects during development, encoding a cellular memory reflected by altered function of progeny cells. Advanced maternal age (AMA) is associated with an increased risk of having a child with ASD for reasons that are not understood. To explore whether AMA involves covert aneuploidy or epigenetic dysregulation leading to ASD in the offspring, we tested a homogeneous ectodermal cell type from 47 individuals with ASD compared with 48 typically developing (TD) controls born to mothers of >/=35 years, using a quantitative genome-wide DNA methylation assay. We show that DNA methylation patterns are dysregulated in ectodermal cells in these individuals, having accounted for confounding effects due to subject age, sex and ancestral haplotype. We did not find mosaic aneuploidy or copy number variability to occur at differentially-methylated regions in these subjects. Of note, the loci with distinctive DNA methylation were found at genes expressed in the brain and encoding protein products significantly enriched for interactions with those produced by known ASD-causing genes, representing a perturbation by epigenomic dysregulation of the same networks compromised by DNA mutational mechanisms. The results indicate the presence of a mosaic subpopulation of epigenetically-dysregulated, ectodermally-derived cells in subjects with ASD. The epigenetic dysregulation observed in these ASD subjects born to older mothers may be associated with aging parental gametes, environmental influences during embryogenesis or could be the consequence of mutations of the chromatin regulatory genes increasingly implicated in ASD. The results indicate that epigenetic dysregulatory mechanisms may complement and interact with DNA mutations in the pathogenesis of the disorder.
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5. Beuker KT, Schjolberg S, Lie KK, Swinkels S, Rommelse NN, Buitelaar JK. {{ESAT and M-CHAT as screening instruments for autism spectrum disorders at 18 months in the general population: issues of overlap and association with clinical referrals}}. {Eur Child Adolesc Psychiatry};2014 (May 28)
The Modified Checklist for Autism in Toddlers (M-CHAT) and the Early Screening of Autistic Traits (ESAT) were designed to screen for autism spectrum disorders in very young children. The aim of this study was to explore proportions of children that screened positive on the ESAT or the M-CHAT and to investigate if screening positive on the ESAT and M-CHAT is associated with clinical referral by 18 months and other aspects of children’s development, health, and behavior. In this study, the mothers of 12,948 18-month-old children returned a questionnaire consisting of items from the ESAT and M-CHAT, plus questions about clinical and developmental characteristics. The M-CHAT identified more screen-positive children than the ESAT, but the ESAT was associated with more clinical referrals and tended to identify more children with medical, language, and behavioral problems. A post hoc analysis of combining the two instruments found this to be more effective than the individual instruments alone in identifying children referred to clinical services at 18 months. Further analysis at the level of single items is warranted to improve these screening instruments.
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6. Dickinson A, Jones M, Milne E. {{Oblique Orientation Discrimination Thresholds Are Superior in Those with a High Level of Autistic Traits}}. {J Autism Dev Disord};2014 (May 29)
Enhanced low-level perception, although present in individuals with autism, is not seen in individuals with high, but non-clinical, levels of autistic traits (Brock et al.in Percept Lond 40(6):739. doi: 10.1068/p6953 , 2011). This is surprising, as many of the higher-level visual differences found in autism have been shown to correlate with autistic traits in non-clinical samples. Here we measure vertical-oblique and, more difficult, oblique-oblique orientation discrimination thresholds in a non-clinical sample. As predicted, oblique-oblique thresholds provided a more sensitive test of orientation discrimination, and were negatively related to autistic traits (N = 94, r = -.356, p < .0001). We conclude that individual differences in orientation discrimination and autistic traits are related, and suggest that both of these factors could be mediated by increased levels of the inhibitory neurotransmitter GABA.
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7. Fava L, Strauss K. {{Response to Early Intensive Behavioral Intervention for autism-An umbrella approach to issues critical to treatment individualization}}. {Int J Dev Neurosci};2014 (May 24)
Integrating knowledge across the disciplines of genetics, neurological, and behavioral science targets, so far, early identification of children with autism and thus early access to intervention. Cross-discipline collaboration might be substantially improve treatment efficacy via individualized treatment based on the child and family needs, consistency across treatment providers and careful planning of skill curricula, setting and techniques. This paper documents the current state of five main issues critical to treatment individualization where cross-discipline collaboration is warranted: (1) developmental timing, (2) treatment intensity, (3) heterogeneity in treatment response, (4) program breath and flexibility, and (5) formats of treatment provision.
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8. Joosten A, Girdler S, Albrecht MA, Horlin C, Falkmer M, Leung D, Ordqvist A, Fleischer H, Falkmer T. {{Gaze and visual search strategies of children with Asperger syndrome/high functioning autism viewing a magic trick}}. {Dev Neurorehabil};2014 (May 27):1-8.
Abstract Objective: To examine visual search patterns and strategies used by children with and without Asperger syndrome/high functioning autism (AS/HFA) while watching a magic trick. Limited responsivity to gaze cues is hypothesised to contribute to social deficits in children with AS/HFA. Methods: Twenty-one children with AS/HFA and 31 matched peers viewed a video of a gaze-cued magic trick twice. Between the viewings, they were informed about how the trick was performed. Participants’ eye movements were recorded using a head-mounted eye-tracker. Results: Children with AS/HFA looked less frequently and had shorter fixation on the magician’s direct and averted gazes during both viewings and more frequently at not gaze-cued objects and on areas outside the magician’s face. After being informed of how the trick was conducted, both groups made fewer fixations on gaze-cued objects and direct gaze. Conclusions: Information may enhance effective visual strategies in children with and without AS/HFA.
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9. Liao ST, Hwang YS, Chen YJ, Lee P, Chen SJ, Lin LY. {{Home-based DIR/Floortime Intervention Program for Preschool Children with Autism Spectrum Disorders: Preliminary Findings}}. {Phys Occup Ther Pediatr};2014 (May 27)
ABSTRACT Improving parent-child interaction and play are important outcomes for children with autism spectrum disorder (ASD). Play is the primary occupation of children. In this pilot study conducted in Taiwan, we investigated the effects of the developmental, individual difference, and relationship-based (DIR)/Floortime home-based intervention program on social interaction and adaptive functioning of children with ASD. The participants were 11 children with ASD, ages from 45-69 months, and their mothers. Mothers were instructed the principles of the approach by an occupational therapist. All 11 children and their mothers completed the 10-week home-based intervention program, undergoing an average of 109.7 hr of intervention. Children made significant changes in mean scores for emotional functioning, communication, and daily living skills. Moreover, the mothers perceived positive changes in their parent-child interactions. The findings of this pilot study contribute to knowledge regarding the effects of home-based DIR/Floortime intervention program on increasing the social interaction and adaptive behaviors of children with ASD in Taiwan.
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10. Nickl-Jockschat T, Rottschy C, Thommes J, Schneider F, Laird AR, Fox PT, Eickhoff SB. {{Neural networks related to dysfunctional face processing in autism spectrum disorder}}. {Brain Struct Funct};2014 (May 29)
One of the most consistent neuropsychological findings in autism spectrum disorders (ASD) is a reduced interest in and impaired processing of human faces. We conducted an activation likelihood estimation meta-analysis on 14 functional imaging studies on neural correlates of face processing enrolling a total of 164 ASD patients. Subsequently, normative whole-brain functional connectivity maps for the identified regions of significant convergence were computed for the task-independent (resting-state) and task-dependent (co-activations) state in healthy subjects. Quantitative functional decoding was performed by reference to the BrainMap database. Finally, we examined the overlap of the delineated network with the results of a previous meta-analysis on structural abnormalities in ASD as well as with brain regions involved in human action observation/imitation. We found a single cluster in the left fusiform gyrus showing significantly reduced activation during face processing in ASD across all studies. Both task-dependent and task-independent analyses indicated significant functional connectivity of this region with the temporo-occipital and lateral occipital cortex, the inferior frontal and parietal cortices, the thalamus and the amygdala. Quantitative reverse inference then indicated an association of these regions mainly with face processing, affective processing, and language-related tasks. Moreover, we found that the cortex in the region of right area V5 displaying structural changes in ASD patients showed consistent connectivity with the region showing aberrant responses in the context of face processing. Finally, this network was also implicated in the human action observation/imitation network. In summary, our findings thus suggest a functionally and structurally disturbed network of occipital regions related primarily to face (but potentially also language) processing, which interact with inferior frontal as well as limbic regions and may be the core of aberrant face processing and reduced interest in faces in ASD.
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11. Yang JC, Niu YQ, Simon C, Seritan AL, Chen L, Schneider A, Moghaddam ST, Hagerman PJ, Hagerman RJ, Olichney JM. {{Memantine Effects on Verbal Memory in Fragile X-associated Tremor/Ataxia Syndrome (FXTAS): a Double-blind Brain Potential Study}}. {Neuropsychopharmacology};2014 (May 29)
Older FMR1 premutation carriers may develop fragile X-associated tremor/ataxia syndrome (FXTAS), a neurodegenerative disorder manifesting cognitive deficits that often subsequently progress to dementia. To date, there is no specific treatment available for FXTAS. Studies have demonstrated the premutation associated overactivation of glutamatergic receptors in neurons. Memantine, a NMDA receptor antagonist approved for treatment of Alzheimer’s disease, thus was tested in the first placebo-controlled, double-blind, randomized clinical trial in FXTAS. Prior event-related brain potential (ERP) studies in FXTAS found reduced N400 repetition effect, a glutamate-related electrophysiological marker of semantic priming and verbal memory processes. This substudy of the randomized clinical trial of memantine in FXTAS sought to use the N400 repetition effect to evaluate effects of chronic memantine treatment on verbal memory. Subsequent recall and recognition memory tests for the experimental stimuli were administered to characterize verbal memory. Data from 41 patients who completed the 1 year memantine trial (21 on memantine) and also completed longitudinal ERP studies were analysed. Results showed treatment-associated benefits on both cued-recall memory and N400 repetition effect amplitude. Importantly, improvement in cued-recall was positively correlated with amplitude increase of the N400 repetition effect. The placebo group, in contrast, displayed a significant reduction of the N400 repetition effect after 1 year. These results suggest that memantine treatment may have beneficial effects on verbal memory in FXTAS. Additional studies of memantine, perhaps in combination with other therapeutic agents, appear warranted, as symptomatic treatments and neuroprotective treatments are both needed for this recently recognized neurodegenerative disorder.Neuropsychopharmacology accepted article preview online, 29 May 2014; doi:10.1038/npp.2014.122.
