I mean, with most things genetically dependent it's more complicated than just A or B, but androgen receptors are on the X chromosome. Baldness basically depends on a couple main things, the rate in which the body converts testosterone to DHT and the DHT affinity of certain binding sites in the follicle. People can still definitely experience androgenic alopecia to varying degrees regardless of that specific X-linked gene, but on balance the mother's brothers and mother's mother's brothers are pretty solid predictors.
Seconded
I mean, with most things genetically dependent it's more complicated than just A or B, but androgen receptors are on the X chromosome. Baldness basically depends on a couple main things, the rate in which the body converts testosterone to DHT and the DHT affinity of certain binding sites in the follicle. People can still definitely experience androgenic alopecia to varying degrees regardless of that specific X-linked gene, but on balance the mother's brothers and mother's mother's brothers are pretty solid predictors.