White hair development model animal, method for establishing white hair development model animal, method for passage of white hair development model animal, method for study on white hair development, screening method for white hair development-control means, and composition for control of white hai

摘要

Disclosed is a non-human model animal which exhibits white hair development with a phenotype such that the colour of the hair first growing after birth is black or almost black and following aging the model animal then exhibits spontaneous white hair development, and wherein the model animal has a gene type that the activated RET gene is genetically inserted in a hetero form and the endothelin receptor B (Ednrb) gene is deficient in a hetero form, or wherein the model animal has a gene type that the activated RET gene is genetically inserted in a hetero form and the Ednrb gene is deficient in the homo form or in a hetero form and the Ednrb gene is genetically inserted in the homo form or in a hetero form under the DbH promoter. Further disclosed is a method of establishing such a non-human mammalian model animal.