It has long been clear that autism runs in families; for some time, scientists have estimated that the likelihood of having a second child with autism is between 3 and 10 percent for families who already have one child with the disorder. Now, a new study appearing in the journal Pediatrics has found that risk to be significantly higher.
The study followed 664 infants who had at least one older brother or sister with autism. The findings showed there was a 19 percent chance a sibling would also have autism; the likelihood rose to 32 percent when two siblings in the family had some form of autism.
Already, up to 15 percent of autism cases have been linked to genetic mutations that, when identified in both parent and autistic child, means autism is heritable. The results of this latest sibling study thus support the idea of a strong genetic component of autism. Therefore, says ACSH s Dr. Gilbert Ross, the fear of unknown environmental factors as a cause of autism for which there has never been any evidence is receding. And this, of course, is a positive turn since research can now focus on the genetic aspects of the disorder instead of having to address the public s vague, unfounded fears that autism can result from exposure to environmental toxins.
ACSH s Dr. Josh Bloom notes that this should drive another nail into the coffin of the asinine vaccine-autism link. This study shows that, whatever the cause or causes of autism may be, there must be a substantial genetic component. Not vaccines. Period.