Philadelphia, PA, July 18, 2016 - A new study in Biological Psychiatry reports that variations in 16p11.2, a region of the genome associated with risk of autism spectrum disorder (ASD), have distinct effects on cognition. The findings highlight the diversity of people with ASD.
Extra or missing copies of genetic material in a small region of the genome in chromosome 16, designated 16p11.2, increases the risk of autism spectrum disorders. Known as duplications or deletions, these alterations in the 16p11.2 genomic region are also associated with intellectual disability.
In the first study to look at the effect of both duplications and deletions in 16p11.2 on specific cognitive domains, senior author Dr. Sébastien Jacquemont, from the University of Montreal in Canada, and a large research team assessed the effects of these variations in 62 deletion carriers, 44 duplication carriers, and 71 controls from within the same families. According to Jacquemont, determining the effect of these alterations can only be performed through family studies. The researchers used neuropsychological tests to assess overall cognitive functioning, fine motor skills, language, memory, and executive functions.
After accounting for the lower IQ associated with 16p11.2 variations, differences in specific cognitive domains emerged. Deletion carriers had difficulty with phonology, reading fluency, fine motor skills, and verbal and motor inhibition. Duplication carriers outperformed controls with the same IQ on tasks of verbal memory, executive functions, and phonological skills. The authors suggest this is reminiscent of the complex and conflicting association between language impairment and autism.
"These data suggest that copy number variants may generally increase risk for intellectual disability and autism, but that the particular nature of the genetic alteration may have specific functional consequences for brain and behavior," said Dr. John Krystal, Editor of Biological Psychiatry.
"Genomic variants associated with ASD may be associated with very different cognitive alterations and profiles," said Jacquemont, "and we may learn something on the developmental mechanisms involved in ASD by focusing on the cognitive comorbidities." He added that generating similar data across other regions of the genome will be essential to understand the impact of different variants on development.
The findings of the study may help better inform the type of intervention that patients will benefit from most; the authors write that the use of visuospatial processes when learning may help patients who carry a deletion, whereas verbal methods may improve learning strategies in patients who carry a duplication.
###
Notes for editors
The article is "The Number of Genomic Copies at the 16p11.2 Locus Modulates Language, Verbal Memory, and Inhibition," by Loyse Hippolyte, Anne M. Maillard, Borja Rodriguez-Herreros, Aurélie Pain, Sandra Martin-Brevet, Carina Ferrari, Philippe Conus, Aurélien Macé, Nouchine Hadjikhani, Andres Metspalu, Anu Reigo, Anneli Kolk, Katrin Männik, Mandy Barker, Bertrand Isidor, Cédric Le Caignec, Cyril Mignot, Laurence Schneider, Laurent Mottron, Boris Keren, Albert David, Martine Doco-Fenzy, Marion Gérard, Raphael Bernier, Robin P. Goin-Kochel, Ellen Hanson, LeeAnne Green Snyder, 16p11.2 European Consortium, Simons Variation in Individuals Project Consortium, Franck Ramus, Jacques S. Beckmann, Bogdan Draganski, Alexandre Reymond, and Sébastien Jacquemont (doi: 10.1016/j.biopsych.2015.10.021). It appears in Biological Psychiatry, volume 80, issue 2 (2016), published by Elsevier.
Copies of this paper are available to credentialed journalists upon request; please contact Rhiannon Bugno at +1 214 648 0880 or biol.psych@utsouthwestern.edu. Journalists wishing to interview the authors may contact Sébastien Jacquemont at sebastien.jacquemont@umontreal.ca.
The authors' affiliations, and disclosures of financial and conflicts of interests are available in the article.
John H. Krystal, M.D., is Chairman of the Department of Psychiatry at the Yale University School of Medicine, Chief of Psychiatry at Yale-New Haven Hospital, and a research psychiatrist at the VA Connecticut Healthcare System. His disclosures of financial and conflicts of interests are available here.
About Biological Psychiatry
Biological Psychiatry is the official journal of the Society of Biological Psychiatry, whose purpose is to promote excellence in scientific research and education in fields that investigate the nature, causes, mechanisms and treatments of disorders of thought, emotion, or behavior. In accord with this mission, this peer-reviewed, rapid-publication, international journal publishes both basic and clinical contributions from all disciplines and research areas relevant to the pathophysiology and treatment of major psychiatric disorders.
The journal publishes novel results of original research which represent an important new lead or significant impact on the field, particularly those addressing genetic and environmental risk factors, neural circuitry and neurochemistry, and important new therapeutic approaches. Reviews and commentaries that focus on topics of current research and interest are also encouraged.
Biological Psychiatry is one of the most selective and highly cited journals in the field of psychiatric neuroscience. It is ranked 5th out of 140 Psychiatry titles and 11th out of 256 Neurosciences titles in the Journal Citations Reports® published by Thomson Reuters. The 2015 Impact Factor score for Biological Psychiatry is 11.212.
About Elsevier
Elsevier is a world-leading provider of information solutions that enhance the performance of science, health, and technology professionals, empowering them to make better decisions, deliver better care, and sometimes make groundbreaking discoveries that advance the boundaries of knowledge and human progress. Elsevier provides web-based, digital solutions -- among them ScienceDirect, Scopus, Elsevier Research Intelligence and ClinicalKey -- and publishes over 2,500 journals, including The Lancet and Cell, and more than 35,000 book titles, including a number of iconic reference works. Elsevier is part of RELX Group, a world-leading provider of information and analytics for professional and business customers across industries. http://www.elsevier.com
Media contact
Rhiannon Bugno
Editorial Office, Biological Psychiatry
+1 214 648 0880
biol.psych@utsouthwestern.edu
Journal
Biological Psychiatry