The Amish, like the Satmar Hasidim, have a major problem with inbreeding and resultant diseases. On any visit to Amish Country in Pennsylvania, one can see clearly multiple-handicapped Amish children being led around.

but they're happy and well-adjusted.

But are a massive burden to everyone around them including the taxpayer.

They ain't heavy--they're our brothers.

Twin studies strongly suggest that autism/Aspergers syndrome have a strong genetic component:

http://www.findarticles.com/p/articles/mi_m0902/is_1_28/ai_61969746

and

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7792363&dopt=Abstract

Anyone who has worked with a lot of software devolopers and computer hardware engineers knows that the milder forms of the disorder seem to be common in these fields. Apparently, Aspergers and autism are increasing in Silicon Valley and other high-tech hotspots:

http://www.wired.com/wired/archive/9.12/aspergers_pr.html

The guy who wrote bittorrent apparently has Aspergers.

Hardly surprising that socially awkward fathers have awkward sons.

Orrin:

They ain't heavy--they're our brothers.

Nice.

OJ,

There is a very good reason why pretty much every society has strong taboos against marrying close relatives.

Not serious ones. You can almost always marry first cousins.

I wonder if there's any correlation between day-care for newborns and autism. I'm just amazed at the number of my software biz coworkers who were back on the job full time after their three months maternity leave was up.

Orrin, if there weren't a strong genetic component, there wouldn't be any difference in rates of occurrence between identical twins and fraternal twins. There is. An adoptive twin study would clinch it, but I haven't seen such a study.

You're sounding like Freud and the psychoanalysts he spawned, who thought that schizophrenia (an organic brain disease, also with a strong genetic component proved by *adoptive twins studies) could be caused by improper toilet training or some other parental failure. Or don't you believe in organic brain diseases?

By the way, if you haven't read it, "The Curious Incident of the Dog in the Night" is a pretty good read. It's a mystery novel as told by a boy with Aspergers syndrome.

Given that we know so little about brain development, one wonders what effect the change from nearly all kids being raised by stay at home mothers to many/most being baby-sat by TV (and now computers) over the past several decades has on brain disorders such as autism, ADD, etc. I don't know anything about genetics, but one suspects that many/most Silicon Valley parents these days stick their kid in front of a computer as soon as they can sit upright. Gee, what a shock that many of these kids might not develop normal brain functionality...

ted:

I believe that when the diagnosis of something sky rockets it is often because folks have a vested interest in the diagnosis, not because there's been an explosion in organic disease.

Have you ever been around an autistic kid? I'll agree that ADD/ADHD could largely be a social construct, but autism is different. Something profound is simply missing from these children, and it is obvious way before they hit school. Calling them "socially awkward" is like calling someone with cerebral palsey "un-athletic."

And if it were due to a parental failure, there wouldn't be such a large gap between the likelihood that fraternal twins will share the disorder (indistinguishable from the rate between siblings), and identical twins (over 80%).

Sure, there's genuine autism. The Amish rate is probably close to right. But the diagnoses nowadays are so bogus they had to invent Asperbergs.