Getting an autism diagnosis could be more difficult in 2013 when a revised diagnostic definition goes into effect. The proposed changes may affect the proportion of individuals who qualify for a diagnosis of autism spectrum disorder, according to a study by Yale Child Study Center researchers published in the April issue of the Journal of the American Academy of Child & Adolescent Psychiatry. The proposed changes to the diagnostic definition will be published in the fifth edition of the American Psychiatric Association's (APA) "Diagnostic and Statistical Manual of Mental Disorders (DSM-5)." "Given the potential implications of these findings for service eligibility, our findings offer important information for consideration by the task force finalizing DSM-5 diagnostic criteria, " said Yale Child Study Center director Fred Volkmar, M.
For children with autism, being born several weeks early or several weeks late tends to increase the severity of their symptoms, according to new research out of Michigan State University. Additionally, autistic children who were born either preterm or post-term are more likely to self-injure themselves compared with autistic children born on time, revealed the study by Tammy Movsas of MSU's Department of Epidemiology. Though the study did not uncover why there is an increase in autistic symptoms, the reasons may be tied to some of the underlying causes of why a child is born preterm (prior to 37 weeks) or post-term (after 42 weeks) in the first place. The research appears online in the Journal of Autism and Development Disorders. Movsas, a postdoctoral epidemiology fellow in MSU's College of Human Medicine, said the study reveals there are many different manifestations of autism spectrum disorder, a collection of developmental disorders including both autism and Asperger syndrome.
Researchers have turned up a new clue to the workings of a possible environmental factor in autism spectrum disorders (ASDs): fathers were four times more likely than mothers to transmit tiny, spontaneous mutations to their children with the disorders. Moreover, the number of such transmitted genetic glitches increased with paternal age. The discovery may help to explain earlier evidence linking autism risk to older fathers. The results are among several from a trio of new studies, supported in part by the National Institutes of Health, finding that such sequence changes in parts of genes that code for proteins play a significant role in ASDs. One of the studies determined that having such glitches boosts a child's risk of developing autism five to 20 fold. Taken together, the three studies represent the largest effort of its kind, drawing upon samples from 549 families to maximize statistical power.
University of Washington researchers announced their findings from a major study looking into the genetic basis of autism spectrum disorders (ASD) with an approach piloted at the UW. Their results are reported in the advanced online edition of the journal Nature. The researchers have been studying ASD in children who have no family history of this or related impairments - so called "sporadic autism" - and also why autism varies in its symptoms and severity. By focusing on "sporadic autism, " the researchers sought to evaluate a specific genetic model for ASD risk, namely the appearance of new mutations (termed de novo) in children with ASD that were not found in either parent. By uncovering new gene mutations that disrupt the function of proteins, the researchers have discovered a pathway related to modifying chromatin - the tightly coiled spools of DNA in the cell - and to regulating genes in the brain and nervous system.
It has long been recognized that autism runs in families, suggesting a substantial genetic component to the disease. Yet few genes have so far been identified and the underlying genetic architecture of autism - that is, how many genes contribute and to what extent they influence a person's chances of developing the disorder - remains poorly understood. Now, a consortium led by researchers from the Broad Institute, Massachusetts General Hospital (MGH), and six other organizations has taken a step toward addressing these questions by searching for mutations in the fraction of the human genome that codes for proteins. The researchers sequenced this region, known as the "exome, " in 175 autism patients and their unaffected parents, looking for single-letter DNA changes present only in the children.