Androgenetic Alopecia

It affects approximately 70% of men and sometimes appears from 18 years of age. It is characterized by a progressive miniaturization of hair replaced by fluff. Although alopecia is hereditary and concerns mainly men (if the father is bald, the son may be, too) women can also be affected.

The gene does not spread automatically from one generation to another. It may well skip a few generations. This form of alopecia can be delayed, but remains inevitable as the specific gene that causes this type of hair loss has not been identified.

Congenital Alopecia

Very rare, it may be due either to the lack of hair roots, or an abnormality of the hair shaft.