Cellular and developmental aspects of androgenetic alopecia, Jahoda -
http://onlinelibrary.wiley.com/doi/10.1111/j.1600-0625.2007.00666.x/pdf
Yes the pattern is interesting. But isn't it interesting too how hair grows in infants? It's pretty much the other way around. The hair at the frontoparietal and frontal regions sometimes grows in last. Also they tend to have 1 follicular units first which progress later to 2-3-4. That's why they have silky hair in the beginning and not much coverage. In Androgenetic Alopecia it's exactly the other way around very often. Progresses to 1 follicular units, and hair loss often starts and the frontoparietal and frontal regions.
What I find interesting also is the following observation;
Eunuchs retain their hair when castrated prepubertally obviously. Now you take one older eunuch and one young eunuch. Both are NW1's. You inject them both with androgens.
The older eunuchs tend to lose their hair extremely rapidly while the younger way more slowly. Why? Cells weaker with old age and more susceptible to stress/damage? I don't know.