'102 genes linked to autism identified'

In the largest genetic study of its kind, researchers have identified 102 genes associated with the risk of autism spectrum disorder (ASD) -- a condition that impairs a person's ability to communicate and interact.

According to the researchers, including those from the Mount Sinai Health System in the US, the current study shows significant progress in understanding the genes in humans associated with ASD which play a part in the symptoms of intellectual disability and developmental delay.

In the study, published in the journal Cell, the scientists analysed more than 35,000 participant samples, including nearly 12,000 with ASD, making it the largest autism sequencing research to date.

They identified 102 genes associated with ASD risk, of which 49 were also linked to other developmental delays.

"This is a landmark study, both for its size and for the large international collaborative effort it required. With these identified genes we can begin to understand what brain changes underlie ASD and begin to consider novel treatment approaches," said Joseph D. Buxbaum, study co-author from Mount Sinai Health System.

The researchers showed that ASD genes impact brain development or function, and that both types of disruptions can contribute to autism.

They also found that two major classes of nerve cells -- excitatory neurons and and inhibitory neurons -- can be affected in autism.

The former, the scientists noted, trigger a positive change in nerve-membranes on getting activated, and inhibitory neurons, they added, spark a negative change on getting excited.

"Through our genetic analyses, we discovered that it's not just one major class of cells implicated in autism, but rather that many disruptions in brain development and in neuronal function can lead to autism," said Buxbaum.

"It's critically important that families of children with and without autism participate in genetic studies because genetic discoveries are the primary means to understanding the molecular, cellular, and systems-level underpinnings of autism," he added.

The researchers believe that the newly discovered roles of several genes may lead to the development of new drugs for autism.