developmental damage can occur to the child in the womb that was not an inherited factor.
Caused possibly by malnutrition of the mother.
Look at FAS (fetal alcohol syndrome).
Look at the role of folic acid in preventing spinal bifida, clearly a developmental dysfunction that was not inherited, but is genetically regulated.
I was speaking specifically of autism. Its behavior is that of a disease that is influenced by many genes and also has some environmental components. Twin studies have shown that both members of identical twin pairs are more likely than fraternal twin pairs to be autistic. That suggests to me that most of the epigenetic changes are already there at conception, and that maybe one or two additional changes in the right genes are enough to cause or prevent autism in someone who is right on the edge. The damage has to occur during development.
My hypothesis could be generalized to an extent to other genetic diseases that seem to have an environmental component, but would not apply to diseases like fetal alcohol syndrome or other diseases caused by malnutrition or exposure to toxins.
Well, if they found a good correlation of autism shared by identical twins, that might be a strong argument for a genetic component.
But then again, they share the same environment, snuggled up next to each other!
So we are back to the whole tabla rasa stuff, is it genetics or is it environment?
This argument will still be going on 1000 years from now... but we will continue to zoom in on the ones we can solve.
On a personal note, I am unwilling to declare HFCS as being totally not at fault here. We simply cannot say for sure now.
But I appreciate very much your knowledge and tone of the discussion. You have shown yourself worthy of having a Ph.D.
I probably could have done it, my fields being Computer Science and psychology, but I was just too lazy and way, way too interested in skirts back then...
;-)