"You must not be paying attention....it does NOT have genetic roots. "

I suspect the term "biological" is not limited to genes, gfs. In addition, if a genetic cause has not been found, that does not rule out other biological causes, whatever they may be, that defines, what one is later in life. I see nothing to either strengthen nor deminish the potential impact of "choice" (in one direction or another) in not finding a genetic cause.IMO, it remains reasonable to consider the liklihood of some variation in cases.