ABSTRACT
Ectodermal dysplasia (ED) defines a disease that involves primary defects in the hair, sweat glands, nails, and teeth (i.e., ectodermally derived structures). This is a vast, heterogeneous group of genetically transmitted diseases that has historically been classified following the famous FreireMaya and Pinheiro classification that encompasses more than 190 different clinical pictures and is based only on clinical evidence. We think that this is rather an old-fashioned way to order and study these diseases, and we accept a more recently proposed classification based on clinical pictures strictly related to molecular and functional genetic findings.
