Home  |  Top News  |  Most Popular  |  Video  |  Multimedia  |  News Feeds  |  Feedback
  Medicine  |  Nature & Earth  |  Biology  |  Technology & Engineering  |  Space & Planetary  |  Psychology  |  Physics & Chemistry  |  Economics  |  Archaeology
Top > Biology > UCLA First to Map Autism-risk… >
UCLA First to Map Autism-risk Genes by Function

Published: November 21, 2013.
By University of California - Los Angeles Health Sciences
http://www.uclahealth.org/

Pity the poor autism researcher. Recent studies have linked hundreds of gene mutations scattered throughout the brain to increased autism risk. Where do you start?

UCLA neuroscientists may have an answer. They are the first to map groups of autism-risk genes by function, and to identify where and when these genes normally play major roles in early brain development.

In addition, they discovered disturbances in neural circuits that define key pathways between parts of the cerebral cortex. The research suggests that these early disruptions are created by mutations in genes during fetal brain development and are not a result of autism itself.

Published in the Nov. 21 edition of Cell, the findings will help scientists understand how genetic changes cause autism on a molecular level and prioritize targets for future studies.

"Identifying gene variants that boost risk is only the first step of unraveling a disease," explained lead author Dr. Daniel Geschwind, the Gordon and Virginia MacDonald Distinguished Professor of Human Genetics, professor of neurology at the David Geffen School of Medicine at UCLA and professor of psychiatry at the Semel Institute for Neuroscience and Human Behavior. "We need to figure out where genetic changes appear in the brain, at what stages during development and which biological processes they disrupt. Only then will we understand how mutations cause autism."

Using an online atlas called BrainSpan, the authors charted gene activity in the developing brain before birth. In particular, they examined what happens during gene expression --when genes copy data from DNA to RNA in order to create proteins.

Geschwind and his colleagues found high activity in risk genes during two processes critical to early brain development.

"We found that gene variants are expressed in the developing brain when cells define their future identities and roles in neural circuits," first author Neelroop Parikshak, a graduate student researcher in Geschwind's lab. "Therefore, changes in the genes influence the brain's wiring by altering the synapse and shaping how neurons transmit signals to each other."

The mutated genes also interfered with how the brain's layers and halves relate to one another, a phenomenon confirmed by previous imaging studies of the autistic brain.

"We discovered gene-related disruption of circuits that connect the autistic brain's layers and hemispheres to each other," explained Geschwind, who is director of the UCLA Neurogenetics Program and the Center for Autism Research and Treatment and co-director of the Center for Neurobehavioral Genetics at UCLA. "Our finding suggests that the mutated genes caused the miswiring; it's not a result of having the disease itself."

The UCLA team also demonstrated that while autism and intellectual disability share similar risk genes, the genes behave uniquely, showing for the first time how the two disorders differ.

"People often lump intellectual disability together with autism, because the disorders' risk genes overlap," said Parikshak. "We showed that these genes have unique expression patterns in different brain regions at varying times during brain development.

"Genes linked to intellectual disability influence many biological processes in the body," he added. "But genes tied to autism tend to affect specific functions, such as the connections between brain regions that are essential to many human-specific behaviors, like speech and language."

The UCLA study will reap immediate benefits in the near future, when neuroscientists sequence the genomes of several thousand people for genetic mutations linked to autism and intellectual disability.

"We've made our analysis publically available to allow other researchers to expand upon our study and explore the data in detail," said Geschwind. "We believe this will mark an important step forward in understanding the biology behind autism and other neurodevelopmental disorders."


Show Reference »


Translate this page: Chinese French German Italian Japanese Korean Portuguese Russian Spanish


 
All comments are reviewed before being posted. We cannot accept messages that refer a product, or web site.If you are looking for a response to a question please use our another feedback page.
Related »

Genes 
5/26/11 
Autism Changes Molecular Structure of the Brain, UCLA Study Finds
By University of California - Los Angeles
For decades, autism researchers have faced a baffling riddle: how to unravel a disorder that leaves no known physical trace as it develops in the brain. …
Brain 
9/29/11 
Autistic Mice Act a Lot Like Human Patients
By University of California - Los Angeles Health Sciences
UCLA scientists have created a mouse model for autism that opens a window into the biological mechanisms that underlie the disease and offers a promising way to test new …
Brain 
8/12/14 
Overhaul of Our Understanding of Why Autism Potentially Occurs
By University of Montreal
MONTREAL, August 12, 2014 – An analysis of autism research covering genetics, brain imaging, and cognition led by Laurent Mottron of the University of Montreal has overhauled our understanding …
Brain 
11/3/10 
UCLA Autism Study Reveals How Genetic Changes Rewire the Brain
By University of California - Los Angeles
Many gene variants have been linked to autism, but how do these subtle changes alter the brain, and ultimately, behavior? …
Autistics 
11/3/11 
Research Reveals Autistic Individuals Are in Fact Superior in Multiple Areas
By University of Montreal
We must stop considering the different brain structure of autistic individuals to be a deficiency, as research reveals that many autistics – not just "savants" – have qualities and …
Brain 
5/13/13 
Brain Frontal Lobes Not Sole Centre of Human Intelligence
By Durham University
Human intelligence cannot be explained by the size of the brain's frontal lobes, say researchers. Research into the comparative size of the frontal lobes in humans and other …
Callosum 
10/19/11 

Bridging the Gap
By California Institute of Technology
Anterior 
5/21/12 
Rare Neurons Discovered in Monkey Brains
By Max-Planck-Gesellschaft
The anterior insular cortex is a small brain region that plays a crucial role in human self-awareness and in related neuropsychiatric disorders. A unique cell type – the von …
Platt 
1/5/12 
Whiff of 'Love Hormone' Helps Monkeys Show a Little Kindness
By Duke University
Oxytocin, the "love hormone" that builds mother-baby bonds and may help us feel more connected toward one another, can also make surly monkeys treat each other a little more …
More » 
 
© Newsline Group  |  About  |  Privacy Policy  |  Feedback  |  Mobile  |  Japanese Edition