Research has found that cases of autism tend to run among siblings. They wanted to determin if there was a way they can narrow there search down. They chose to look for sex-specific autism susceptibilities among siblings. This essentially would allow them to search for higher families that hold a higher risk of having multiple autistic children. It would also give them new information they did not yet have on the cause of autism and its behavior. What they discovered was that there is a collation between the sex of siblings and the likeliness that they will be born with autism.
The article I looked at is available here
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