A Hypohidrotic Ectodermal Dysplasia Arising From a New Mutation in a Yorkshire Terrier Dog

Hypohidrotic ectodermal dysplasias (HED) constitute a group of genetic disorders that affect ectodermal derivatives such as sweat glands, sebaceous glands, hair, and teeth. The vast majority of cases of HED are caused by a recessive mutation of the EDA gene located in the X chromosome. In these cases, affected individuals are usually male and have alopecia and hypotrichosis with characteristic distribution, in addition to malformed teeth and fewer than normal. From a canine HED isolated case (proband) andc in order to verify if this emerged from a new mutation, it was possible to construct a pedigree with 5 generations and 93 individuals representing an extended and informative family. The proband's mother crossed with 2 different males and generated 33 descendants in 9 gestations: 1 affected male (proband), 15 normal males, and 17 normal females, which together can be considered as 1 sibship. Through Bayesian inference, it was possible to establish that this case originated from a new mutation, with a 99.99% probability of the mother of the proband not being a carrier.