Bedrockgames
I post in the voice of Christopher Walken
Well, now you have to be careful.
Can you tell the difference between a "genetic disorder" and a fairly normal genetic composition that simply can't handle the amount of crap we now dump into our environments, or the way we raise some of our kids?
Consider - what have we done more of in the past centuries: changed our genetics, or changed our environment and behavior? Are you really convinced that children from, say, 300 or 500 years ago, moved into our current environments, would not develop similar problems?
Note that the correlation of allergy and autoimmune disease to income level goes a bit against what many would expect. Your chance of having a problem *increases* with your income level - rich kids are more likely to have allergies and autoimmune diseases than poor kids.
I am not disputing any of that. Just pointing out there may also be a genetic component and those who are gentically predisposed may develop these issues while others may not. In short it seems to be an interpla between our genes and the things going on inthe environment.