Pattern hair loss is primarily caused by DHT, which induces transforming growth factor beta-1 and leads to apoptosis in dermal papilla cells.

“we've talked about the evidence supporting the claims that dht is this causative agent in pattern hair loss we know that mechanistically it induces that signaling protein transforming growth factor beta 1. it leads to apoptosis and epithelial cells in the dermal papillai cell network we also know at a bird's eye view that men who lack the ability to produce dht don't go bald that men who were castrated before puberty don't go bald and then if you give men dht injections they'll go bald even if they've been castrated”