Alopecia areata is more common in young females, and changes in appearance significantly reduce the patient's quality of life (QOL), especially in whole-head and generalized cases.The autoimmune theory is mentioned as the pathogenic mechanism, and it is said that it is a multifactorial disease related to many genes and factors, but the cause and mechanism are unknown.Attempts have been made around the world to elucidate the causative gene for alopecia areata, but it has not been identified.

　This time, the research group extracted and analyzed genomic DNA from the peripheral blood of patients with alopecia areata and healthy subjects, and statistically estimated at which genomic site the gene related to the disease was present.As a result, it was found that the causative gene exists near the gene called HLA-C.Next, the HLA genomic region of the patient's chromosome was compared with the base sequence of a healthy person. An amino acid substitution has occurred in a gene called CCHCR1, which has been found to be a risk allele (an allele that increases the risk of developing alopecia areata) involved in the development of alopecia areata.

　Therefore, when a genome-edited mouse into which the risk allele of this CCHCR1 gene was introduced was created using a genome-editing method, hair loss similar to that of a human alopecia areata patient occurred in the mouse.Furthermore, it was found that the gene expression pattern and hair shaft status of alopecia areata patients with risk allele are very similar to those of genome-edited mice.

　By clarifying the difference between cases with and without risk allele of the CCHCR1 gene, the results of this research will enable the development of type-specific diagnostic methods for alopecia areata and treatment methods specific to each type. It is supposed to be.

Paper information:[EBioMedicine] Alopecia areata susceptibility variant in MHC region impacts expressions of genes contributing to hair keratinization and is involved in hair loss