For what's it worth?, imo, part of the answer is correlated with the enzymatic super families.

AKR 1C2 (aldo-keto reductase)
17b HSD (hydroxysteroid dehydrogenase)
3b HSD (hydroxysteroid dehydrogenase)
11b HSD (hydroxysteroid dehydrogenase)
21OH (hydroxylase)

Otherwise known as the "gate keepers".