A study released in April, 2009, has found that there is a gene variant common among 20 percent of children with autism and that may have a role in 12 to 18 percent of autism cases. The DNA was found in the fontal cortex, the region of the brain where language and communication is housed.

While there is no cure for autism, there are effective treatments and interventions. The results of this new study may impact successful treatments. Gerard Schellenberg, a professor at the University of Pennsylvania School of Medicine, the study’s author, states that “When we think about treatments, those target molecules and you have to know what to target. This is a major jump in terms of knowing what we need to look at.”

The molecules on the variant gene help to shape the developing brain’s structure, and the gene variant this study found acts as a link between the brain’s wiring and the child’s development. Found on chromosome 5, the gene variant occurs in normally developing children as well. Researchers think that there may be other high-risk variants at work in autistic children.

A second study by a research group led by Hakon Hakonarson from the Center for Applied Genetics at the Children’s Hospital of Philadelphia, replicated the results of the first study and examined the link between genes that help eliminate connections between nerve cells. The results of the study underscore the theory that abnormal connections between nerves in the brain cause autism.

“Both studies implicated genes involved in synaptic generation and neuronal connectivity,” Hakonarson said. “This is highly consistent with previously published research.”
Hakonarson also posits that environmental factors have a role in autism.

Recently, the National Institutes of Health has made autism a priority research topic and has pledged $60 million to research into the differences within the range of autism spectrum disorders. Research will focus on developing screening tools, assessing risks, and adapting existing interventions to best help treat children with an autism diagnosis.

These findings challenge a study that previously held that brain abnormalities in autistic children resulted from their brain’s faster development.

The technique used in this study measured the water properties of brain tissue. In the normally developing brain, water is incorporated into neurons rapidly for the first 6 months of life, and then slows for the next 18 months. The University of Washington study found that, in the autistic brain, water was more mobile. This finding suggests a delay in the development of neurons, specifically at the grey matter at the brain’s surface.

Dager suggests delays could be caused by inflammation: “If you’ve got inflammation, it can affect connectivity at a critical stage of brain development.” This inflammation during the first year of life could lead to learning problems. “For example,” Dager states, “a child has certain key developmental stages for learning language and if you miss those it can be harder to learn that language.”

This early inflammation, Dager suggest, may be due to a particular gene. Research into genetic links to autism is ongoing, but Matthew Belmonte, senior research associate at the Autism Research Center at the University of Cambridge asserts that “Until we know exactly what it is that causes the abnormal development of grey matter we cannot develop drug treatments.” Belmonte suggests that “One might look at genes that cause a susceptibility to inflammation instead [of brain changes].”

Whatever the focus of the research, learning more about the causes of this complex disorder can only help researchers to develop more, and more effective, treatment and intervention possibilities.