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.
Researchers at the University of Pennsylvania, who were investigating the biological causes of androgenetic alopecia or common genetic hair loss, have discovered that levels of a certain inhibitor protein, called Prostaglandin D2 (PD2), are elevated in bald areas on the scalp. This discovery could be an important breakthrough in developing a medical hair loss treatment that regulates the production of the protein, or one that blocks it from attaching to its receptor protein.
Dr. Angela Christiano, a colleague of Dr. Bernstein’s at Columbia University, has been studying the causes of alopecia areata and genetic hair loss for many years. She, in fact, suffers from the disease as well.
The New York Times has published a question and answer interview with Dr. Christiano which covers her own struggle with alopecia, her research into the causes of genetic hair loss, and where she sees the field going in the future.
Dr. Angela Christiano of Columbia University in New York and a team of scientific researchers, have identified a new gene involved in hair growth. Their discovery may affect the direction of future research for hair loss and the diagnosis and ultimate prevention of male pattern baldness.
The condition, which leads to thinning hair, is called hereditary hypotrichosis simplex. Through the study of families in Pakistan and Italy who suffer from this condition, the team was able to identify a mutation of the APCDD1 gene located in chromosome 18. This chromosome has been linked to other causes of hair loss.
Japanese scientists have located a gene that seems to regulate hair loss in mice. They feel that this gene may also play a role in hair loss in humans. The results of the studies were recently reported in the Proceedings of the National Academy of Sciences.
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.
Summary of Dr. Sinclair’s Abstract from his presentation at the International Society of Hair Restoration Surgery, 2005 – Sidney, Australia.
Twin studies have confirmed the strong heredity of androgenetic alopecia. The purpose of the present study is to explore the genetic basis of androgenetic alopecia by gene analysis. The study compared the sequence of several candidate genes between groups of individuals considered to be most and least genetically predisposed to androgenetic alopecia. Most likely are young males who already have a significant degree of baldness and least likely are those who are older and have no sign of hair loss.