Pubmed du 13/03/09

Pubmed du jour

2009-03-13 12:03:50

1. Depienne C, Moreno-De-Luca D, Heron D, Bouteiller D, Gennetier A, Delorme R, Chaste P, Siffroi JP, Chantot-Bastaraud S, Benyahia B, Trouillard O, Nygren G, Kopp S, Johansson M, Rastam M, Burglen L, Leguern E, Verloes A, Leboyer M, Brice A, Gillberg C, Betancur C. {{Screening for Genomic Rearrangements and Methylation Abnormalities of the 15q11-q13 Region in Autism Spectrum Disorders}}. {Biol Psychiatry};2009 (Mar 10)

BACKGROUND: Maternally derived duplications of the 15q11-q13 region are the most frequently reported chromosomal aberrations in autism spectrum disorders (ASD). Prader-Willi and Angelman syndromes, caused by 15q11-q13 deletions or abnormal methylation of imprinted genes, are also associated with ASD. However, the prevalence of these disorders in ASD is unknown. The aim of this study was to assess the frequency of 15q11-q13 rearrangements in a large sample of patients ascertained for ASD. METHODS: A total of 522 patients belonging to 430 families were screened for deletions, duplications, and methylation abnormalities involving 15q11-q13 with multiplex ligation-dependent probe amplification (MLPA). RESULTS: We identified four patients with 15q11-q13 abnormalities: a supernumerary chromosome 15, a paternal interstitial duplication, and two subjects with Angelman syndrome, one with a maternal deletion and the other with a paternal uniparental disomy. CONCLUSIONS: Our results show that abnormalities of the 15q11-q13 region are a significant cause of ASD, accounting for approximately 1% of cases. Maternal interstitial 15q11-q13 duplications, previously reported to be present in 1% of patients with ASD, were not detected in our sample. Although paternal duplications of chromosome 15 remain phenotypically silent in the majority of patients, they can give rise to developmental delay and ASD in some subjects, suggesting that paternally expressed genes in this region can contribute to ASD, albeit with reduced penetrance compared with maternal duplications. These findings indicate that patients with ASD should be routinely screened for 15q genomic imbalances and methylation abnormalities and that MLPA is a reliable, rapid, and cost-effective method to perform this screening.

2. Faber S, Zinn GM, Kern Ii JC, Skip Kingston HM. {{The plasma zinc/serum copper ratio as a biomarker in children with autism spectrum disorders}}. {Biomarkers};2009 (Mar 11):1-10.

The frequency of zinc deficiency, copper toxicity and low zinc/copper in children with autism spectrum disorders (ASDs) may indicate decrement in metallothionein system functioning. A retrospective review of plasma zinc, serum copper and zinc/copper was performed on data from 230 children with autistic disorder, pervasive developmental disorder-NOS and Asperger’s syndrome. The entire cohort’s mean zinc level was 77.2 mug dl(-1), mean copper level was 131.5 mug dl(-1), and mean Zn/Cu was 0.608, which was below the 0.7 cut-off of the lowest 2.5% of healthy children. The plasma zinc/serum copper ratio may be a biomarker of heavy metal, particularly mercury, toxicity in children with ASDs.

3. Golnik AE, Ireland M. {{Complementary Alternative Medicine for Children with Autism: A Physician Survey}}. {J Autism Dev Disord};2009 (Mar 11)

Previous studies suggest over half of children with autism are using complementary alternative medicine (CAM). In this study, physicians responded (n = 539, 19% response rate) to a survey regarding CAM use in children with autism. Physicians encouraged multi-vitamins (49%), essential fatty acids (25%), melatonin (25%) and probiotics (19%) and discouraged withholding immunizations (76%), chelation (61%), anti-infectives (57%), delaying immunizations (55%) and secretin (43%). Physicians encouraging CAM were more likely to desire CAM training, inquire about CAM use, be female, be younger, and report greater autism visits, autism education and CAM knowledge. Physicians were more likely to desire CAM training, inquire about CAM and view CAM as a challenge for children with autism compared to children with other neurodevelopmental and chronic/complex conditions.

4. Orekhova EV, Stroganova TA, Prokofiev AO, Nygren G, Gillberg C, Elam M. {{The right hemisphere fails to respond to temporal novelty in autism: Evidence from an ERP study}}.{ Clin Neurophysiol};2009 (Mar 9)

OBJECTIVE: This study aimed to investigate electrophysiological correlates of initial attention orienting to temporally novel sound in children with autism (CWA). METHODS: Twenty-one CWA (4-8 years) and 21 age-matched typically developing children (TDC) were presented with pairs of clicks separated by a 0.5s intra-pair interval, with longer (7-9s) intervals between pairs. Children watched a silent movie during click presentation. We assessed EEG perturbations and event-related potentials (ERP) in response to sounds of different temporal novelty – first (S1) and second (S2) clicks in the pair. RESULTS: In TDC, the early attention-modulated midtemporal N1c wave evoked by S1 and corresponding EEG phase locking and power increase were right-lateralized and were bilaterally higher than those evoked by S2. CWA demonstrated abnormal S1 responses, characterized by reduced N1c amplitude and EEG phase locking in the right midtemporal region, reversed leftward lateralization of the phase locking, and diminished later frontal N2 wave. Their brain responses to S2 were essentially normal. CONCLUSIONS: The impaired right hemispheric processing of temporary and contextually novel information and suboptimal lateralization of normally right-lateralized attention networks may be important features of autistic disorder. SIGNIFICANCE: Results of this study contribute to the understanding of autism neurobiology.

5. Wiggins LD, Robins DL, Bakeman R, Adamson LB. {{Brief Report: Sensory Abnormalities as Distinguishing Symptoms of Autism Spectrum Disorders in Young Children}}. {J Autism Dev Disord};2009 (Mar 13)

The purpose of this study was to explore the sensory profile of young children with ASD compared to young children with other developmental delays (DD) at first ASD assessment. Results found that young children with ASD had more tactile and taste/smell sensitivities and difficulties with auditory filtering than young children with other DD. Moreover, sensory scores were significantly correlated with stereotyped interests and behaviors. These findings support the hypotheses that young children with ASD show more sensory impairments than young children with other DD and that sensory symptoms are significantly related to stereotyped interests and behaviors. Results also suggest that sensory abnormalities are distinguishing symptoms of ASD that should be considered in diagnostic algorithms for younger cohorts.