Hair Biology and Androgenetic Alopecia

This document from 2018 discusses the biology of hair growth and androgenetic alopecia (AGA), a common form of hair loss. AGA is caused by a combination of genetic and hormonal factors, which lead to the miniaturization of hair follicles and eventual hair loss. The document provides information on the typical characteristics of hair and diagnostic tests for AGA. The loss of progenitor cells in the sub-bulge region of hair follicles may lead to miniaturization or loss of anagen follicles and eventually baldness. The document suggests that further investigations are needed to determine whether the loss of these cells represents a primary or secondary event in AGA. The article also discusses various types of hair loss and their treatments, including regenerative medicine as a potential alternative to conventional therapies.