Regarding genetics of male pattern baldness.
First of all , male pattern baldness, the most common cause of nonscarring alopecia (baldness) is inherited in a
polygenic fashion or a trait inherited by
either or both of the parents. It may be a sex limited due to incomplete expression and penetrance but not X linked inheritance like color blindness. Male pattern baldness is a classic example of how inheritance pattern for something as simple as balding cannot be explained by pure Mendelian genetics . We now know it can be inherited from
both parents and can have incomplete penetrance thus, have varying levels of expression in the person who carries the gene. Ie: you can have the gene, but you don't go bald or you can look like Yule Brennor.
The hormonal environment has to be right therefore, men express it early due to high levels of testosterone and byproduct hormones. Women can express it early if they have untreated congential adrenal hyperplasia (where the adrenal glands overproduce male hormones) and carry the gene or a ovarian tumor that produces testosterone. The latter women are lucky to have the balding gene, since this is how the docs find out a young woman has an ovarian cancer (she startes balding at 30). The hormonal mileu of the women approaches that of men after menapause (higher ratio of testosterone to estrogen) (Remember, our adrenal glands continue to make testosterone until death) so some women who carry the gene will start expressing it then. Also overactive or underactive thyroid can cause hair loss.
Intersting there is a racial preferrance. Androgenic alopecia is responsible for male pattern baldness in fifty percent of white men and women over 40 but the percentage is less in asians, blacks and lastly, American Indians. So the idea of coinheritance (say a racial gene inherited with the balding gene ) may also be important.
Some people may not have the gene and still have age related miniaturization of the hair follicles and it can look like incomplete balding. These people probably won't respond to Propecia (a 5-alpha reducatse inhibitor) but might respond to Rogaine (don't really know the mechanism of action of the latter).
Most of all, remember, we have yet to isolate the specific gene or set of genes exclusively responsible for male pattern baldness!!!!
As for prohormones causing male pattern baldness...some more than others depending on where in the steroid cycle they appear. If you want to slow down the progression of baldness, stop the prohormones, but I suspect it has uncovered or accellerated your genetic propensity for baldness later in life.
If guys want to minimize their chance of going bald, you can get castrated (thus stopping the major source of testosterone production) but don't forget, you have to rip out your adrenal glands too.
