Researchers from the University Hospital of Bonn and the University of Bonn have made significant progress in understanding male pattern hair loss by identifying the role of rare genetic variants. Through their study, which analyzed data from over 72,000 men, the researchers identified five key genes associated with male pattern hair loss. These findings pave the way for better treatment and risk assessment of this common condition.

Male pattern hair loss, also known as androgenetic alopecia, is characterized by a receding hairline, hair loss at the crown, and eventually a horseshoe-shaped pattern of baldness. Previous studies have identified common genetic variations related to this condition. However, the contribution of rare genetic variants has been less explored until now.

The research conducted by the University Hospital of Bonn and the University of Bonn's Transdisciplinary Research Unit "Life & Health" involved a comprehensive analysis of the genetic sequences of 72,469 male participants from the UK Biobank project. This large-scale analysis revealed five significantly associated genes, as well as corroborating genes previously implicated in male pattern hair loss. The results of the study have been published in the prestigious scientific journal Nature Communications.

Studying rare genetic variants poses unique challenges, as it requires large cohorts and capturing the genetic sequences base by base through genome or exome sequencing. However, the researchers utilized gene-based analyses that collapsed the variants based on the genes in which they were located. This approach enabled them to overcome statistical challenges associated with rare variants that may be carried by a very small number of individuals.

The analysis of the genetic sequences from the extensive UK Biobank data set led to the discovery of rare gene variants in five genes: EDA2R, WNT10A, HEPH, CEPT1, and EIF3F. Two of these genes, EDA2R and WNT10A, were already considered candidate genes based on previous analyses of common variants. The study further supports their involvement in male pattern hair loss through both common and rare variants. Additionally, the study identified HEPH as a potential candidate gene, despite not previously being considered.

The genes CEPT1 and EIF3F, which were not previously associated with male pattern hair loss, were also found to be located in genetic regions that may contribute to the genetic predisposition of the condition. These new candidate genes provide valuable insights into the genetic factors underlying hair development and growth.

Furthermore, the study suggests that genes known to cause rare inherited diseases affecting the skin and hair, like ectodermal dysplasias, may also play a role in the development of male pattern hair loss.

The researchers hope that these findings will enhance understanding of the causes of hair loss, ultimately leading to more accurate risk prediction and improved treatment strategies. The identification of the specific genetic variants associated with male pattern hair loss provides a foundation for the development of targeted therapies for individuals affected by this condition.

The study was supported by funding from the Medical Faculty of the University of Bonn, with Prof. Dr. Markus Nöthen from the Institute of Human Genetics at the University Hospital of Bonn serving as a co-author. The publication costs were funded by the DEAL project of the University of Bonn, allowing the study to be published in an open-access format.

Further research in this field will build upon these significant findings, potentially revolutionizing the treatment and management of male pattern hair loss in the near future.

Reference: "Analysis of 72,469 UK Biobank exomes links rare variants to male-pattern hair loss" by Sabrina Katrin Henne, Rana Aldisi, Sugirthan Sivalingam, Lara Maleen Hochfeld, Oleg Borisov, Peter Michael Krawitz, Carlo Maj, Markus Maria Nöthen and Stefanie Heilmann-Heimbach, 22 September 2023, Nature Communications.