[heartwood]

if these random mutations are the only or primary cause of autism, it does not make sense that the incidence of autism has increased so much in the last twenty-five years.

If something was causing a greater number of mutations, we would be seeing an increase in all kinds of birth defects and cancers.

[newzjunkey]

if these random mutations are the only or primary cause of autism, it does not make sense that the incidence of autism has increased so much in the last twenty-five years.

All manner of things may effect fertility. There are different medications, diets, additives, lifestyles, pollutants, household products than 25 years ago. Some of the higher incidence may be a change in diagnoses.

If something was causing a greater number of mutations, we would be seeing an increase in all kinds of birth defects and cancers.

That doesn't necessarily follow.

[wolfman23601]

Not so sure the incidence of “autism” has really increased... just a lot of quacks that diagnose it. They even tried to tell my parents my brother was on the autism spectrum. He just graduated from William and Mary, is off to grad school, and is perfectly normal socially. He was just a little shy as a child. Don’t get me wrong, I am not saying autism is fake, just way overdiagnosed.

[fso301]

if these random mutations are the only or primary cause of autism, it does not make sense that the incidence of autism has increased so much in the last twenty-five years.

May just be more refined diagnostic criteria