Can we test for the FFA genes?
Since the announcement last month that 4 new genes were discovered to play a role in frontal fibrosing alopecia (FFA), I have been asked several times if patients can arrange to have these genes tested for themselves of their families. The short answer is that such testing is not available yet, nor do we know yet how to properly use this information.
There were four main genes identified but one in particular stood out as carrying the highest risk compared to the other 3 genes. This was HLA-B*07:02 on chromosome 6. This gene is part of the major histocompatibility complex (MHC). This appears to be highly relevant because the HLA-B is an important so called “immune recognition gene.” A variation in these genetic coding in these immune recognition genes is thought to contribute to autoimmunity - which in the case of FFA would lead to autoimmune destruction of the hair follicle. What was remarkable in this study was the observation that specific mutations in the HLA B gene carried a 4.73 fold increased risk of developing FFA. When I look at the data, this points to a really significant association. It is this gene that might influence how autoantigens get presented to the immune system.
We don’t yet know how to use this information and whether there are other environmental risk factors that are more important or equally important to be exploring or testing at present. These are exciting times for new research in FFA. However, these are still the early days of understanding this information and how to use it properly.
Christos Tziotzios et al. Genome-wide association study in frontal fibrosing alopecia identifies four susceptibility loci including HLA-B*07:02. Nature 2019. Online March 8, 2019
Dr. Jeff Donovan is a Canadian and US board certified dermatologist specializing exclusively in hair loss. To schedule a consultation, please call the Whistler office at 604.283.1887