Ectodermal Dysplasia: Rapp-Hodgkin Syndrome and Hay-Wells Syndrome

The group of ectodermal dysplasia (ED) disorders encompasses a diverse collection of developmental anomalies affecting skin, hair, teeth, nails, and sweat glands, often with other syndromic features. Rapp-Hodgkin syndrome and Hay-Wells syndrome represent two eponymous forms of ED which both result from similar mutations in TP63 , encoding the transcription factor, p63. The often overlapping phenotypes and mutations in these two conditions has led to debate as to whether they are variable expressions of the same clinicopathologic entity. Nevertheless, the clinical and molecular data collectively illustrate the importance of p63 in skin and other tissue development and homeostasis.