Well, there were studies that showed that when hair follicles from the assumed to be genetically immune occipital region of scalp were exposed to supraphysiologic levels of DHT, they too undergo miniaturization. I don't know of any studies that did this too people who were Native American but my take is, even people who would never bald under normal circumstances, given high enough DHT exposure for a long enough time frame, they too will undergo Androgenetic Alopecia. I believe all human scalp hair behave this way just like all body hair grows in response to DHT. It's just varying degrees of resistance that we perceive as "immune".
There is also research indicating that given a long enough time line, all men would eventually get prostate cancer (barring any preventative therapy) due to DHT exposure and the reason not all men do is because something else kills them first.
this was an interesting case where a female with diffuse pattern even in the traditionally more "DHT resistant" areas experience hair fall with high prolactin levels