Genetic Causes of Hair Loss

The most common cause of long-standing hair thinning is male and female pattern hair loss (also known as androgenetic alopecia, AGA).  The term androgenetic combines the fact that both hormones and genetics play a role. The term alopecia is an umbrella term used to refer to all types of hair loss. We qualify the type of hair loss by using other terms to describe it (alopecia areata, or cicatricial alopecia). 

Learn More About These Terms

Today, dermatologists and other hair loss experts prefer to use the terms male pattern hair loss (MPHL) and female pattern hair loss (FPHL).

Male and female pattern hair loss runs in families, and is considered ‘polygenic,’ meaning it comes from many different genes from many different ancestors. Your father may have started balding at an early age, or you may have a twin sister who wears a wig. There is evidence that the androgen receptor (AR) gene plays an important role, and we are still accumulating evidence to better understand this.  What if you cannot identify a relative with thinning hair? This doesn’t rule out inherited thinning as a cause, especially if it has been long-standing.

Polycystic Ovarian Syndrome (Stein-Leventhal Syndrome)

This is a condition that affects may women in the form of irregular periods, infertility, insulin-resistance, hirsutism, acne and hair thinning.  If you think you may have this condition, you should see your gynecologist and/or dermatologist as soon as possible. You may be able to benefit from anti-androgen therapies that help normalize your symptoms and reduce your hair loss.

Alopecia Areata

Alopecia areata is an autoimmune condition that can result in round or oval patches of hair loss on the scalp or anywhere else on the body. The cause is usually a combination of genetics (family history) and exacerbating environmental factors such as stress. It is seen more often in children, but can appear for the first time in adults, too. Most patients who have this condition have limited patches of hair loss but the involvement can spread to involve the back of the scalp (ophiasis pattern) or the entire scalp (alopecia totalis) or the entire body (alopecia universalis). More information can be found about this disease at

Cicatricial Alopecias

1) Central Centrifugal Cicatricial Alopecia (CCCA) is a common cause of hair loss among persons of African descent. It can presents with symptoms of itching or tenderness in the central vertex of the scalp (see diagram) and can appear as an area of short, broken hairs or as an area of thinning.  It is called centrifugal because the patch can slowly enlarge in size outward from the vertex. The term cicatricial refers to the scarring nature of this condition. Unfortunately, when this condition is allowed to progress it can result in permanent scarring and it can be impossible to regrow the hair. For this reason, most dermatologists have the goal of cooling off the inflammation with a combination of topical steroids or injected steroids so that no further hair is lost. Some patients who present with extreme inflammation or pustules may need oral antibiotics to cool off their condition. 

2) Frontal Fibrosing Alopecia is a relatively new condition that was only described in the mid-1990s. It can result in permanent hair loss along the frontal hairline, as well as thinning or loss of eyebrows. Affected persons may also notice loss of body hair and/or tiny facial papules along the cheeks and temples. Because of the permanent nature of this hair loss condition, you should see your dermatologist as soon as possible to start treatment and avoid further hair loss.

3) Lichen Planopilaris is a cousin to frontal fibrosing alopecia, but it appears as round or oval plaques of hair loss on the top or sides of the scalp. Affected persons are more likely to complain of itching, scaling, or tenderness where the hair loss has appeared. Your doctor may perform a scalp biopsy to confirm this condition. Because of the permanent scarring nature of this condition, it should also be treated aggressively by a board-certified dermatologist or hair expert.