Tallchief-

Something I learned with distinction in the biotech industry is that the effect of 'genetics' is a nature AND nurture proposition.

Certain ramifications of genetic 'programming' require stimulus from outside the constraints of essential gene code in order to attain 'expression' of a 'genetic trait' so to speak.

For instance, you might have the genetic wiring to be driven completely out of your gourd by red-headed women.
Chances are you'd be able to maintain a completely sane and solid demeanor through your lifetime - save for some or other type of contact with red-headed women.

Catch my drift..?

Cheers
Tinker