Genetic testing for baldness genes offers hope to prevent hair loss.
Has science really gotten to the point where it can accurately predict future hair loss in order to provide a definitive answer to the question of whether you will lose your hair? Well, yes and no …
A lot of hair loss news was made in 2009 when HairDX came out with its genetic screening test for predicting male or female pattern hair loss (androgenetic alopecia). The objective of the HairDX screening test is to identify, prior to the onset of symptoms, whether a person will experience pattern hair loss. Hair restoration and hair loss experts alike agree that since most of the treatments and preventions for hair loss work best before we lose our hair, it would be useful to know whether a patient was genetically predisposed to certain types of hair loss — and to what degree.
How does genetic testing for hair loss work?
The test is sold to doctors in a kit and administered by a simple cheek swab. The HairDX genetic test for male pattern hair loss looks for the presence of a specific variation in the androgen receptor gene (AR) found on the X chromosome. The variant AR gene causes changes in the hair follicle’s response to dihydrotestosterone (DHT), leading to follicle miniaturization and alterations in the hair growth cycle. But according to the International Society of Hair Restoration Surgery, genetic predisposition is known to be an underlying cause of male pattern hair loss but the genetic predisposition is not clearly understood and no “baldness gene” has been identified with certainty. Although family history frequently reveals genetic history of male pattern hair loss in close male relatives, 20 percent of men with male pattern hair loss have no family history of the disorder. In addition, the pattern and extent of male pattern hair loss may differ in men of Caucasian, Asian, African, or Native American descent. As for women, a different variable is tested, called a “CAG repeat,” with an inverse relationship between the length of gene and the probability of hair loss in women.
Is genetic hair loss testing foolproof?
Dr. Eric Schweiger, M.D., a board-certified dermatologist and a hair transplant surgeon at Bernstein Medical — Center for Hair Restoration in New York City, explains, “I think the test has probably identified a predictor of hair loss but not the only predictor. There is science behind the test and some published research studies; however, the longitudinal, larger studies have not been done, because this testing procedure is just too new.” Dr. Robert Bernstein, M.D., director at Bernstein Medical Center, agrees and adds, “These tests focus on one particular dominant gene, but what is becoming apparent is that hair loss is a complex genetic condition most likely involving several different genes.” He further notes that age, stress, hormone levels, disease and many other factors also are at play in determining factors for hair loss. “Just because a person has the genes for baldness, it doesn’t mean the trait will manifest itself. The truth is the cause and effect have not been proven and differ from person to person, and the association is not anywhere near 100 percent.”
The bottom line on genetic hair loss testing
Both doctors agree that it is important to identify those at high risk of becoming bald, before it is apparent clinically, so that hair loss can be treated in its earliest stages when medications have the greatest chance of success. But it’s also important not to overreact to the relatively incomplete information that the test provides. Any genetic testing should be performed under a doctor’s supervision so that it can be put in the context of other information he or she gleans through a careful history, a physical, and a densitometry hair evaluation. “Right now, we predict future hair loss based on follicle miniaturization, using advanced microscopic equipment,” says Dr. Schweiger, “and I advise a man to do this at around age 25. If someone presents with more than 25 percent miniaturization, then it’s time to start a hair loss prevention regimen.”