The Inheritance of Androgenetic Alopecia: Father’s Father ... Mother’s Father ... or Father’s Mother?

Androgenetic alopecia is common in the general population. In fact, the condition is often called “common balding”.  Approximately 50-60 % of men and 30-40 % of women will develop androgenetic alopecia by the age of 50.  

When I meet with patients, I generally ask about the hair characteristics of his or her mother and father.  I try to get a sense of his or her parent’s hair density and the age at which the parents started losing hair.   Although men and women with androgenetic alopecia often have a family history of androgenetic alopecia, it’s not absolutely necessary for the diagnosis.   In fact, a family history is least likely to be found in women diagnosed with androgenetic alopecia.  This is because the inheritance of androgenetic alopecia is much more complicated in women than in men.

There are many myths when it comes to hair loss and patients are often surprised to hear me say that the chance to inherit hair loss comes from both sides of the family tree.  Upon hearing this I commonly hear patients reply:

I thought hair loss came from the mother’s father?

or ... I thought hair loss came from the father’s mother?

or ... I thought hair loss came from the father’s father?

The main message is that hair loss is inherited from both mother and father and their respective sides of the family tree.  It’s possible for children to have high hair densities in adulthood even if dad has androgenetic alopecia.  Furthermore, it’s possible (albeit uncommon) for children to have significant androgenetic alopecia when dad or mom have minimal hair loss in adulthood.