Three other studies come to underline the idea that genetic mutations are present in about 65 percent of kids diagnosed with ASD.

 

The author of two of the studies, Hakon Hakonarson, MD, PhD, director of genomics research at The Children’s Hospital of Philadelphia, wanted to highlight the idea that having the variant does not automatically mean a person will develop autism, because besides genetics, environmental factors and other genetic factors are thought to play an important role in developing the condition.

 

For one of the studies, Hakonarson and his colleagues conducted a genome-wide association study on 780 families, including 3.101 participants with affected kids and then a second group of 1,204 people with autism or ASD and 6,491 in a comparison group. The researchers scanned for markers across the complete set of the DNA to find genetic variations associated with specific diseases.

 

They found only one region that differentiated itself, namely the region of chromosome 5 involving the genes that facilitate cell-to-cell communication -- CDH9 and CDH10. These genes carry codes to produce crucial neuronal cell-adhesion molecules, Hakonarson says. “They sit on the surface of nerve cells and facilitate and create cell-to-cell communication.”

Given the findings, the hopes are to identify these variants at birth or even in utero so intervention can begin early. It has been shown that early treatment for autism increases a kid’s chances to improve.

The other study of Hakonarson and colleagues involved the same ADN analysis but this time the researchers wanted to find genes that were either duplicated or deleted in those with autism or ASD. The analysis involved 2,195 kids with ASD and 2,519 healthy kids.

 

The researchers found some previously reported genes, but also some new ones.

 

Both studies, published in the journal Nature, were accompanied by a third study in the Annals of Human Genetics, led by Margaret Pericak-Vance, PhD, director of the Miami Institute for Human Genomics at the University of Miami Miller School of Medicine.

 

By using the same technique, “we found the same thing as the Nature paper,” Pericak-Vance said, adding that the new research is “the most significant finding to date, the most universal finding to date, that clearly shows common gene variants can play a role in giving someone a risk for autism.”

Autism is a disorder that affects the development of the brain. The disease involves impaired social interaction and communication, as well as restricted and repetitive behavior, all starting before one’s third birthday. Starting the 1980s, the number of autism cases has increased significantly. As maintained by the Centers for Disease Control and Prevention, about 1 in every 150 children has autism or a related disorder.