Two more links in the scientific chain detailing a genetic predisposition for autism have been found by an international team of researchers, three of whom are at the University of Utah.
In two studies published in today's edition of the journal Nature, researchers describe a common gene variant that occurs 20 percent more often in autistic children and new "susceptibility genes" not previously linked to autism spectrum disorders.
Hilary Coon, co-author of the studies and research professor of psychiatry at the U., said the new details add to "lots of small effect findings" in recent years that seek to find specific genetic components for autism.
The first study — the largest ever to examine genetic factors in autism — found a gene variation that may disrupt communication between nerve cells and play an important part in 12 percent to 18 percent of autism cases.
The genetic variant is found near a gene that is active in developing the region of the brain necessary for language and judgment. The gene encodes a type of protein that affects how nerve cells communicate with each other.
The second study identified new copy-number variations in genes, where short segments of DNA are duplicated or deleted in the genomes of autistic children. The studies included participation by 150 Utahns who are part of ongoing autism research.
Coon said the complexity of autism spectrum disorders in the brain means research into the causes is excruciatingly slow. "It must be very frustrating from the standpoint of a family member," who hopes for new treatment techniques or interventions.
She said any kind of wonder medication to cure autism is still "in the realm of science fiction," but as research progresses, there may be hope for future parents whose children will be affected. If researchers could help to "identify someone at risk early on so you could get them early intervention, that's the one thing now that allows someone with this to live life to the fullest and not be held back," she said.
Environmental factors are also "hugely important" in determining what causes autism, but tracking those down can be even trickier than detailing the genetic components, she said.
Though Utah is reported to have a higher rate of autism among children, Coon said, "we don't really have a statistically higher prevalence here" if you examine carefully how the statistics are gathered.
"It's higher, but that's probably more due to better record keeping here and a really good extraction team that managed to get more cases."
Some have speculated that Utah's autism rate of may be due to the polygamous family relationships among some early Mormon settlers. Coon said the U. has "ongoing pedigree studies of autism," through the Utah Population Database, which includes genealogical records of LDS pioneers.
"We don't find an increase in autism in general among that group of people. But we find clusters of autism within families that no one else can really do, because records we have are so rich."