Scientists Discover Genetic Link to Autism in New Study

Scientists may have just found a genetic link to autism. They've discovered a mutation in the CHD8 gene that causes people with it to have a "strong likelihood of developing autism marked by gastrointestinal disorders, a larger head and wide set eyes.

"We finally got a clear cut case of an autism specific gene," said Raphael Bernier, one of the researchers, in a news release.

Autism has currently been linked to different types of genetic events. The most commonly researched genetic events are chromosomal re-arrangements, called "copy number variations." These occur in which a chunk of chromosome is copied or deleted.

In this case, the scientists studied 6,176 children with autism spectrum disorder. In the end, they found 15 had a CHD8 mutation and that all of these cases had similar characteristics in appearance and issues with sleep disturbance and gastrointestinal problems.

In order to confirm the findings, the scientists then used zebra fish. The researchers disrupted the CHD8 gene in the fish; this caused the fish to develop large heads and wide set eyes. Then, the scientists fed the fish fluorescent pellets and found that they had problems discarding food waste.

This is the first time ever that researchers have shown a definitive cause of autism to a genetic mutation. Previous identified genetic events, like Fragile X, are associated with other impairments, such as intellectual disability, more than autism.

"This will be a game changer in the way scientists are researching autism," said Bernier.

The findings could pave a way to a "genetics-first approach" that could further uncover hundreds more genetic mutations and lead to genetic testing. This testing could help guide families and show them what to expect and how to care for their children.

The findings are published in the journal Cell.