I have one typical child and one with autism. what are the odds my next child would have autism?

Slight risk: We do not understand the genetic mechanisms for autism. We do know that there is an increased risk in families with a history of autism. However, since we have not found a definite cause and only recently noted chromosomal changes in autistic children, we cannot say what the risk is for certain. There may even be environmental components at work, so avoid toxins perinatally.

Much research is : Is focused on siblings of children with autistic spectrum disorder. Each specific genetic disorder found on comparative genomic hybridization or dna probe for fragile x carries its own risk. Otherwise, prospective studies show that 20-30% of younger siblings display signs of asd, but very early intervention led to some later diagnoses of language disorders or milder symptoms than their older sib.