London, England - The London Daily Mail is reporting that scientists from around the world have made a breakthrough in what causes autism. Below is the story by Sarah Griffiths.
Scientists have taken a breakthrough step towards understanding exactly what causes autism.
Researchers from 13 institutions around the world have discovered that people with a mutation of the CHD8 gene have a 'very strong' likelihood of having autism.
The new study found the gene mutation was marked by common characteristics, including gastrointestinal disorders, a larger head and wide set eyes.
It is the first time researchers have linked a definitive cause of autism to a genetic mutation, the team claim.
Associate professor at the University of Washington, and lead author of the new research, Raphael Bernier, said: 'We finally got a clear cut case of an autism specific gene.’
In the study, published in Cell magazine, 6,176 children with autism spectrum disorder were anaylsed.
Researchers found 15 had a CHD8 mutation and all of these children had similar characteristics in appearance.
The 15 children also shared sleep disturbance and gastrointestinal problems.
Professor Bernier and his team worked with scientists at Duke University who specialise in zebra fish modelling.
The Duke team disrupted the CHD8 gene in the fish, and noted they developed large heads and wide set eyes.
They then fed the fish fluorescent pellets and found that the fish had problems discarding food waste and were constipated.
Professor Bernier said this is the first time that researchers have linked a definitive cause of autism to a genetic mutation.
Although just 0.5 per cent of all children have the kind of autism related to the CHD8 mutation, he said that there are lots of implications from the study.
‘This will be a game changer in the way scientists are researching autism,’ Professor Bernier said.
The results could pave the way for a ‘genetics-first approach’ that could uncover hundreds more genetic mutations and lead to genetic testing, he explained.
Genetic testing could be offered to families as a way of guiding them on what to expect and how to care for their child.
Currently autism is diagnosed by doctors examining and assessing a child's behavior.
In the short term, Professor Bernier said that clinicians can pay attention to the small population with this CHD8 mutation and provide targeted treatment.
Autism has already been linked to different types of genetic events. The most commonly researched genetic events associated with autism are chromosomal re-arrangements, called ‘copy number variations,’ in which a chunk of chromosome is copied or deleted.
But no one rearrangement affects more than one per cent of all autism cases and there is no definitive link between the rearrangement and autism.
The CHD8 gene mutation is the first gene mutation to show a ‘very strong penetrance’ – or link - to a certain subtype of autism.