Genetic Changes in Male Hair Cycle

Balding is a common occurrence with increased age that is likely due to cellular stress and damage in hair follicles from free radicals. In comparison, the direct cause of common male balding (AGA) is faulty hair follicle cycle regulation. Specifically, the genes that stimulate the growth phase in the hair cycle are decreased while those that induce the resting, shedding, and pre-growth phases are increased or maintained in men with AGA.⁽¹⁶⁾

Recent gene research has uncovered the important role of one particular gene in androgenetic hair loss. Hair follicles that have increased number of androgen receptors are more sensitive to excess androgen hormones (such as DHT) linked to hair loss. The gene that controls the expression of androgen receptors in hair follicles may actually account for up to 40% of the total hereditary risk of balding in men.⁽³²³⁾

Further, the influence of the AR gene appears to depend on its location on the mother's X chromosome. This means maternal lineage is important in genetic risk of male AGA.⁽³²³⁾