1. Boria S, Fabbri-Destro M, Cattaneo L, Sparaci L, Sinigaglia C, Santelli E, Cossu G, Rizzolatti G. {{Intention understanding in autism}}. {PLoS ONE};2009;4(5):e5596.
When we observe a motor act (e.g. grasping a cup) done by another individual, we extract, according to how the motor act is performed and its context, two types of information: the goal (grasping) and the intention underlying it (e.g. grasping for drinking). Here we examined whether children with autistic spectrum disorder (ASD) are able to understand these two aspects of motor acts. Two experiments were carried out. In the first, one group of high-functioning children with ASD and one of typically developing (TD) children were presented with pictures showing hand-object interactions and asked what the individual was doing and why. In half of the « why » trials the observed grip was congruent with the function of the object (« why-use » trials), in the other half it corresponded to the grip typically used to move that object (« why-place » trials). The results showed that children with ASD have no difficulties in reporting the goals of individual motor acts. In contrast they made several errors in the why task with all errors occurring in the « why-place » trials. In the second experiment the same two groups of children saw pictures showing a hand-grip congruent with the object use, but within a context suggesting either the use of the object or its placement into a container. Here children with ASD performed as TD children, correctly indicating the agent’s intention. In conclusion, our data show that understanding others’ intentions can occur in two ways: by relying on motor information derived from the hand-object interaction, and by using functional information derived from the object’s standard use. Children with ASD have no deficit in the second type of understanding, while they have difficulties in understanding others’ intentions when they have to rely exclusively on motor cues.
2. Cusco I, Medrano A, Gener B, Vilardell M, Gallastegui F, Villa O, Gonzalez E, Rodriguez-Santiago B, Vilella E, Del Campo M, Perez-Jurado LA. {{Autism-specific copy number variants further implicate the phosphatidylinositol signaling pathway and the glutamatergic synapse in the etiology of the disorder}}. {Hum Mol Genet};2009 (May 15);18(10):1795-1804.
Autism spectrum disorders (ASDs) constitute a group of severe neurodevelopmental conditions with complex multifactorial etiology. In order to explore the hypothesis that submicroscopic genomic rearrangements underlie some ASD cases, we have analyzed 96 Spanish patients with idiopathic ASD after extensive clinical and laboratory screening, by array comparative genomic hybridization (aCGH) using a homemade bacterial artificial chromosome (BAC) array. Only 13 of the 238 detected copy number alterations, ranging in size from 89 kb to 2.4 Mb, were present specifically in the autistic population (12 out of 96 individuals, 12.5%). Following validation by additional molecular techniques, we have characterized these novel candidate regions containing 24 different genes including alterations in two previously reported regions of chromosome 7 associated with the ASD phenotype. Some of the genes located in ASD-specific copy number variants act in common pathways, most notably the phosphatidylinositol signaling and the glutamatergic synapse, both known to be affected in several genetic syndromes related with autism and previously associated with ASD. Our work supports the idea that the functional alteration of genes in related neuronal networks is involved in the etiology of the ASD phenotype and confirms a significant diagnostic yield for aCGH, which should probably be included in the diagnostic workup of idiopathic ASD.
3. David FJ, Baranek GT, Giuliani CA, Mercer VS, Poe MD, Thorpe DE. {{A pilot study: coordination of precision grip in children and adolescents with high functioning autism}}. {Pediatr Phys Ther};2009 (Summer);21(2):205-211.
PURPOSE: This pilot study compared temporal coordination during a precision grip task between 13 children and adolescents with autism spectrum disorders (ASD) who were high functioning and 13 peers with typical development. METHODS: Temporal coordination between grip and load forces was measured using latency between onset of grip and load forces, grip force at onset of load force, peak grip force (PGF), and time to PGF. RESULTS: Compared with peers with typical development, participants with ASD demonstrated prolonged latency between grip and load forces, elevated grip force at onset of load force, and increased movement variability. PGF and time to PGF were not significantly different between the 2 groups. CONCLUSIONS: These findings indicate temporal dyscoordination in participants with ASD. The findings also enhance our understanding of motor coordination deficits in persons with ASD and have theoretical as well as clinical implications.
4. Geier DA, Kern JK, Garver CR, Adams JB, Audhya T, Nataf R, Geier MR. {{Biomarkers of environmental toxicity and susceptibility in autism}}. {J Neurol Sci};2009 (May 15);280(1-2):101-108.
Autism spectrum disorders (ASDs) may result from a combination of genetic/biochemical susceptibilities in the form of a reduced ability to excrete mercury and/or increased environmental exposure at key developmental times. Urinary porphyrins and transsulfuration metabolites in participants diagnosed with an ASD were examined. A prospective, blinded study was undertaken to evaluate a cohort of 28 participants with an ASD diagnosis for Childhood Autism Rating Scale (CARS) scores, urinary porphyrins, and transsulfuration metabolites. Testing was conducted using Vitamin Diagnostics, Inc. (CLIA-approved) and Laboratoire Philippe Auguste (ISO-approved). Participants with severe ASDs had significantly increased mercury intoxication-associated urinary porphyrins (pentacarboxyporphyrin, precoproporphyrin, and coproporphyrin) in comparison to participants with mild ASDs, whereas other urinary porphyrins were similar in both groups. Significantly decreased plasma levels of reduced glutathione (GSH), cysteine, and sulfate were observed among study participants relative to controls. In contrast, study participants had significantly increased plasma oxidized glutathione (GSSG) relative to controls. Mercury intoxication-associated urinary porphyrins were significantly correlated with increasing CARS scores and GSSG levels, whereas other urinary porphyrins did not show these relationships. The urinary porphyrin and CARS score correlations observed among study participants suggest that mercury intoxication is significantly associated with autistic symptoms. The transsulfuration abnormalities observed among study participants indicate that mercury intoxication was associated with increased oxidative stress and decreased detoxification capacity.
5. Gerhard T, Chavez B, Olfson M, Crystal S. {{National patterns in the outpatient pharmacological management of children and adolescents with autism spectrum disorder}}.{ J Clin Psychopharmacol};2009 (Jun);29(3):307-310.
6. Hernandez RN, Feinberg RL, Vaurio R, Passanante NM, Thompson RE, Kaufmann WE. {{Autism spectrum disorder in fragile X syndrome: A longitudinal evaluation}}. {Am J Med Genet A};2009 (May 13)
The present study extends our previous work on characterizing the autistic behavior profile of boys with fragile X syndrome (FXS) who meet Diagnostic and Statistical Manual for Mental Disorders, 4th Edition criteria for autism spectrum disorder (ASD) into a longitudinal evaluation of ASD in FXS (FXS + ASD). Specifically, we aimed to determine the stability of the diagnosis and profile of ASD in FXS over time. Through regression models, we also evaluated which autistic and social behaviors and skills were correlates of diagnosis and autistic behavior severity (i.e., Autism Diagnostic Interview-Revised total scores). Finally, we assessed the evolution of cognitive parameters in FXS + ASD. A population of 56 boys (30-88 months at baseline) with FXS was evaluated using measures of autistic, social, and cognitive behaviors and skills at three yearly evaluations. We found that the diagnosis of ASD in FXS was relatively stable over time. Further emphasizing this stability, we found a set of behaviors and skills, particularly those related to peer relationships and adaptive socialization, that differentiated FXS + ASD from the rest of the FXS cohort (FXS + None) and contributed to autistic severity at all time points. Nevertheless, the general improvement in autistic behavior observed in FXS + ASD coupled with the concurrent worsening in FXS + None resulted in less differentiation between the groups over time. Surprisingly, FXS + ASD IQ scores were stable while FXS + None non-verbal IQ scores declined. Our findings indicate that ASD is a distinctive subphenotype in FXS characterized by deficits in complex social interaction, with similarities to ASD in the general population. (c) 2009 Wiley-Liss, Inc.
7. Martin BJ. Re: {{Biomarkers of environmental toxicity and susceptibility in autism}}. {J Neurol Sci};2009 (May 15);280(1-2):127-128; author reply 128-129; discussion 129-130.
8. Mohammad NS, Jain JM, Chintakindi KP, Singh RP, Naik U, Akella RR. {{Aberrations in folate metabolic pathway and altered susceptibility to autism}}. {Psychiatr Genet};2009 (May 13)
OBJECTIVE: To investigate whether genetic polymorphisms are the underlying causes for aberrations in folate pathway that was reported in autistic children. BASIC METHODS: A total of 138 children diagnosed as autistic based on Diagnostic and Statistical Manual of Mental Disorders, fourth edition criteria and Autism Behavior Checklist scoring and 138 age and sex matched children who are nonautistic were tested for five genetic polymorphisms, that is, cytosolic serine hydroxyl methyl transferase (SHMT1 C1420T), methylene tetrahydrofolate reductase (MTHFR C677T and MTHFR A1298C), methionine synthase reductase (MTRR A66G), methionine synthase (MS A2756G) using PCR-restriction fragment length polymorphism methods. Fisher’s exact test and logistic regression analysis were used for statistical analyses. RESULTS: MTHFR 677T-allele frequency was found to be higher in autistic children compared with nonautistic children (16.3 vs. 6.5%) with 2.79-fold increased risk for autism [95% confidence interval (CI): 1.58-4.93]. The frequencies of MTRR 66A allele (12.7 vs. 21.0%) and SHMT 1420T allele (27.9 vs. 45.3%) were lower in autistic group compared with nonautistic group with odds ratios 0.55 (95% CI: 0.35-0.86) and 0.44 (95% CI: 0.31-0.62), respectively, indicating reduced risk. MTHFR 1298C-allele frequency was similar in both the groups (53.3 vs. 53.6%) and hence individually not associated with any risk. However, this allele was found to act additively in the presence of MTHFR 677T allele as evidenced by 8.11-fold (95% CI: 2.84-22.92) risk associated with MTHFR 677CT+TT/1298AC+CC genotypes cumulatively. CONCLUSION: MTHFR C677T is a risk factor, whereas MTRR A66G and SHMT C1420T polymorphisms reduce risk for autism. MTHFR A1298C acts additively in increasing the risk for autism.
9. Shinawi M, Patel A, Panichkul P, Zascavage R, Peters SU, Scaglia F. {{The Xp contiguous deletion syndrome and autism}}. {Am J Med Genet A};2009 (May 13)
Xp22 nullisomy in males causes a phenotype consistent with the loss of one or more of the genes located in this chromosomal region. Females with similar Xp deletions rarely manifest the same phenotype. Here we describe a 10-year-old girl with a de novo interstitial deletion encompassing Xp22.2p22.32 who presented with autism, moderate mental retardation, and some dysmorphic features. The deletion was delineated by FISH and STR analyses, and the breakpoints were determined using the Agilent 244 K oligonucleotide array. We found that the 5.5 Mb deletion is located on the paternal X chromosome and encompasses 18 genes. Further molecular and cytogenetic analyses showed unfavorable skewing of X-inactivation of the maternal (intact) chromosome. The phenotype of our patient was compared with previously reported female patients with deletions encompassing the same chromosomal region. We discuss the potential role of the genes in the deleted region and X chromosome inactivation in the pathogenesis of the phenotypic abnormalities seen in our patient. Our findings suggest that the severity and the variability of the clinical findings are determined by the size and the parental origin of the deletions as well as the X-inactivation status. (c) 2009 Wiley-Liss, Inc.
