Genetica

A study released Thursday is shedding light on why autism spectrum disorder affects four times more boys than girls — and may point toward a future treatment for the condition.
The study, which waspublished in the American Journal of Human Genetics, was conducted by a team of international researchers led by The Hospital for Sick Children (SickKids) in Toronto and McMaster University inHamilton, Ont.
Researchers analyzed the genes of more than 1,600 people with autism, leading them to uncover a key genetic clue that possibly explains the gender bias: an alteration in the SHANK1 gene."When we try to think about clues to lead us in the right direction we look for differences, and I think the biggest difference that's always stuck out in autism is this issue of gender," said Dr.Stephen Scherer, senior scientist and director of the Centre for Applied Genomics at SickKids and the McLaughlin Centre at the University of Toronto.
"Now, for the first time, we've identified a so-calledinherited form of autism that's not on the X or Y chromosome.
"We don't know if it accounts for all autism yet, but we certainly think that it is a significant proportion," he said.
The SHANK genefamily provides the blueprint for proteins that are involved in forming neural synapses in the brain and how these synapses function.
Synapses are regions in the brain and nervous system where nerveimpulses are sent and received between cells.
When neural synapses aren't properly formed, or cannot function properly due to gene mutation, it can cause a broad range of problems depending on themalfunction, including symptoms associated with autism. Those symptoms include problems communicating and interacting socially.
During the study, six people from a "multigenerational family" were foundto carry the SHANK1 mutation. Of these six people, only the men had autism.
Scherer said there is now more insight as to why men are more susceptible to autism than women as a result of this study....