Update on ectodermal dysplasias clinical classification.

Monogenic genetic disorders constitute a very large group of rare conditions, each of which is defined by a characteristic combination of phenotypic features. Their enormous clinical variability and their etiological heterogeneity may result in difficulties for the establishment of a syndromic diagnosis. In this context, classifications were proposed for different nosological groups, including ectodermal dysplasias. Freire-Maia proposed a clinical based classification, but nowadays the need of connecting clinical and molecular data on EDs demands a re-evaluation of the knowledge and the formulation of a new classification approach. The aim of this article is to provide an update of an article published in 2009 in this Journal. In order to check for new articles and information on ectodermal dysplasias, we have consulted the OMIM, PUBMED, and Science Direct online databases.