Update on the genetics of androgenetic alopecia, female pattern hair loss, and alopecia areata: implications for molecular diagnostic testing.

Androgenetic alopecia, female pattern hair loss, and alopecia areata are among the most common forms of nonscarring hair loss encountered in clinical practice. Although the exact pathogenesis of these forms of alopecia remains to be clarified, genetic factors appear to have a significant contribution to their pathogenesis. Current treatment strategies are limited and their effectiveness remains modest at best. This review summarizes the current purported pathogenesis and recent genetic discoveries relating to these forms of alopecia. The role of molecular diagnostic testing is also discussed in relation to its future clinical utility for the prediction of developing hair loss, the diagnosis of the type of alopecia, prediction of disease severity, development of novel therapeutic and preventative targeted treatments, as well as determination of response to therapy.