The Genetics of Androgenetic Alopecia
March 2001
in “
Clinics in Dermatology
”
TLDR Genes and hormones cause hair loss, with four genes contributing equally.
Androgenetic alopecia is a genetic and hormonal type of hair loss that affects specific areas of the scalp and causes hair follicles to produce short, fine hairs. The exact role of androgens in this process is not completely understood. The condition is caused by multiple genes, with each of four genes contributing 25% towards predisposition. The mode of inheritance is polygenic and follows a normal curve. The androgen receptor gene is increased in balding scalp, but its location on the X chromosome does not explain father-to-son transmission. A decrease in the enzyme aromatase may result in an increased level of testosterone available for conversion to DHT. The gene encoding aromatase (CYP19) is worth investigating. Minoxidil is a treatment that regulates VEGF. Studying the genetic basis of androgenetic alopecia may lead to better treatments.