Study of Human Leukocyte Antigen in 13 Cases of Familial Frontal Fibrosing Alopecia: CYP21A2 Gene p.V281L Mutation from Congenital Adrenal Hyperplasia Linked to HLA Class I Haplotype HLA-A*33:01; B*14:02; C*08:02 as a Genetic Marker

The study examined the genetic predisposition to familial frontal fibrosing alopecia (FFA) in 13 patients from six families by analyzing their human leukocyte antigen (HLA) profiles and the CYP21A2 gene mutation. It was found that 61.5% of the patients had the CYP21A2 gene p.V281L mutation associated with the F16A HLA class I haplotype (HLA-A*33:01; B*14:02; C*08:02), which is linked to nonclassical congenital adrenal hyperplasia. This haplotype and mutation were suggested as genetic markers for susceptibility to FFA, indicating a potential antigen-driven mechanism for the disease. The study, despite its small sample size, highlighted the significance of a shared low-frequency MHC extended haplotype among most patients and suggested that these findings could lead to targeted treatments after further confirmation in sporadic FFA cases.