It appears that hair loss is inherited, but we don't really know how. The following are possible ways it could be inherited:
- A problem with a single gene that may or may not affect all men the same
- A problem with a pair of genes that are related to sex chromosomes
- A problem with multiple genes
A person who experiences hair loss can have a family history of hair loss on either side of the family. On the other hand, there may be no family history of hair loss. The good news is - if you have someone in your family who has hair loss, it doesn't mean you will have hair loss, also.
Sources: Stough, Dow, et al. "Psychological Effect, Pathophysiology, and Managment of Androgenic Alopecia in Men." Mayo Clinic Proceedings 80(2005): 1316-22.

