Are Gene-Hunting Scientists Getting Close to Solving the Mystery of Male Pattern Baldness?
Study finds strong links between hair loss and serious diseases, including Parkinson’s and ALS.
During the past decade, scientists have learned a lot about the role of genetics in androgenetic alopecia, better known as male pattern baldness. Even so, much more information and study is needed for researchers to understand the role various genetic risk factors play in contributing to hair loss.
The paper, “Hunting the genes in male-pattern alopecia: how important are they, how close are we and what will they tell us?” was recently published in the journal, Experimental Dermatology. Researchers led by Dr. Stefanie Heilmann of the University of Bonn in Germany, concluded that, “...researchers remain far from having established firm relationships between identified gene associations and particular biological characteristics in affected hair follicles.”
This should serve as a reality check for those who suggest that commonly available DNA tests can identify an individual’s susceptibility to male pattern baldness. The condition is far from binary (yes, you have the ‘hair loss gene’ / no, you don’t). As Dr. Heilmann and her team describe, there are 12 genomic regions of interest.
We won’t get into too much detail – if you are interested, we encourage you to read the paper linked above – but the most plausible candidate gene for male pattern baldness is known as the AR gene. It is located on the long arm of the X-chromosome (at position 12), which is inherited from the mother. The AR gene provides instructions for making a protein called an androgen receptor. There is a second gene of interest in the same region known as EDA2R, which is a protein coding gene.
These genes are definitely believed to be involved in some cases of male pattern baldness, but as the researchers point out, they are the tip of the iceberg. Here is a brief excerpt from the paper:
“…follow-up analyses conducted to date could neither confirm nor exclude the AR or EDA2R as the true causative gene, or lead to the identification of the causal variant(s). Moreover, no plausible explanation has yet been provided for why a genetically determined overall functional effect on AR signaling should result in hair cycle abnormalities and abnormal terminal-to-vellus transformation in specific skin regions only, whereas the growth of hair follicles elsewhere remains normal and is in fact stimulated by the same ligand (dihydrotestosterone). Further studies are warranted to elucidate the connection between genetic variation at the AR/EDA2R-locus and the androgen-dependent development of the AGA phenotype.”
Since these two genes are passed from the mother, how do you explain the occasional similarities of hair loss patterns in fathers and sons? That’s where the 11 other genomic regions of interest come into play. The researchers say these are located on what are called the “autosomes,” which are inherited equally from an individual’s father and the mother.
What particularly caught our attention at Arocha Hair Restoration is how researchers addressed those who question whether scientists are investing too much time and energy to understand the underlying genetic causes of what is perceived as merely a cosmetic condition. They say the evidence indicates that those with male pattern baldness are at increased risk for the following:
- Benign prostate hyperplasia
- Prostate cancer
- Cardiovascular disease (hypertension, coronary heart disease and heart attacks)
- Metabolic syndrome
Additionally, the researchers point to a potential association between male pattern baldness and Parkinson's disease that has never been published previously. Analysis of data from the 23andMe population revealed a significantly higher risk of Parkinson's disease among those with male pattern baldness. The association became even stronger when the analysis was restricted to individuals over age 70.
“This suggests that (male pattern baldness) and Parkinson's disease share a common biological mechanism,” stated Dr. Heilmann’s paper.
Additionally, the researchers found that those who have early-onset male pattern baldness are up to 2.7 times more likely to be at risk of amyotrophic lateral sclerosis (ALS, also known as Lou Gehrig’s Disease).
This isn’t intended to freak you out. It is exciting that we are learning more all the time about how our genes map out our future. If we find that male pattern baldness is actually an early and easily identified symptom or marker indicating a likelihood or risk of a future disease, we will eventually be able to take action to prevent disease.
All of this will take time, probably at least a decade or more, but it will happen in our lifetimes. What a wonderful time to be alive!