I would bet a lot of money it's genetic.
In the never-ending "Nature vs. Nurture" debates ... some things are nature (inherited) ... some things are nurture (environmental) ... and most things are some combination of both.
However, the propensity for hormonal imbalances that cause problems, I would think, has to lean more toward the "Nature" (genetic/inheritable) side of things.
That is a guess, but I think a fairly educated one.