Dr. Bernstein addresses the common myth that hair loss is inherited exclusively from the mother’s side of the family – and, more specifically, from your mother’s father. While your mother’s (or maternal grandfather’s) genes can be the culprit, the characteristics of your hair are influenced by many different genes that may come from either or both sides of your family.
What are the chances that I will go bald? How bald will I be? Can I know for sure? These are among the most common questions we get from patients in our hair loss consultations. Despite extensive knowledge about the mechanisms and causes of androgenetic alopecia (common baldness), the answers to these questions have been a bit hazy. New research has sharpened the focus on the genetic mix that results in hair loss and has enabled more accurate predictions. A study published in February 2017 in the journal PLoS Genetics identified over 250 gene locations newly linked to hair loss. Using this information, researchers more accurately predicted severe balding compared to previous methods.
Dr. Bernstein was interviewed by Dana Tyler, host of the television program “Eye on New York” on CBS, for the show that aired on April 17th. The wide-ranging interview was the feature in a 9-minute segment on hair transplantation and hair loss. Read further for a partial transcript of the interview.
Q: There was a retrospective study by Lotufo et al. linking male pattern baldness to heart disease. Do you think there are other links like this for androgenetic alopecia?
A: Family studies revealed both the androgen receptor locus on the X chromosome, as well as a new locus on chromosome 3q26. Association studies performed in two independent groups revealed a locus on chromosome 20 (not near any known genes) as well as the androgen receptor on the X chromosome. Read on for the rest of the answer.
Q: Is it worth getting the genetic test for balding?
A: You’re referring to Hair DX (hairdx.com), which costs about $150 and came to market in January of 2008 as the first test for androgenetic alopecia, aka male pattern baldness.
The test screens for variations in the androgen receptor gene on the X chromosome, the gene that is associated with male pattern hair loss. The purpose of the test is to identify persons at increased risk of developing hair loss before it is clinically apparent – so that medical intervention can be started early, when it is most effective.
The HairDX genetic test for hair loss offers information that can aid you and your doctor in making an informed decision about the treatment of your hair loss. It offers one more bit of information that, in the context of other data (such as hair loss pattern, scalp miniaturization and family history) can help guide you and your doctor to formulate an appropriate treatment plan. How does it work? How accurate is the test? How does the test compare to information obtained from a history and physical exam by your physician? Dr. Bernstein answers these questions and more on the HairDX genetic test for hair loss.
Q: What are the genes that cause male pattern baldness?
A: At this time the genes that actually cause hair loss are still unknown.
However, there are two gene loci, recently identified, that appear to be associated with common baldness. The first is on the Androgen Receptor (AR) gene carried on the x-chromosome and the second is a non-sex chromosome 20p11.
We all have seen that some bald sons have bald fathers, even when no one on the mother’s side of the family has any hair loss. This suggests that the genetics of male pattern alopecia is more complicated, with multiple genes influencing hair growth. And it is likely that the inheritance of baldness is polygenetic, with relevant genes coming from both the x-chromosome of the mother and non-sex chromosomes of either parent. So where are the other genes?
Two independent research groups, one from England and the other Germany, both published in the journal Nature Genetics, have identified a gene locus p11 on chromosome 20 that seems to be correlated with male pattern hair loss, and since the gene is on a non-sex chromosome, it offers an explanation for why the inheritance of common baldness can be from either side of the family.
Hair loss has a variety of causes. Diagnosis and treatment is best determined by a board-certified dermatologist. We offer both in-person and online photo consults.