Ankyloblepharon–ectodermal dysplasia–cleft lip/palate (AEC) syndrome and Rapp–Hodgkin syndrome are well-characterized clinical entities caused by mutations in the TP63 gene. While AEC and Rapp–Hodgkin had been thought to be clinically distinct entities, the elucidation of their molecular etiology confirmed that they are a clinical continuum as opposed to distinct disorders. We have evaluated 17 patients with AEC syndrome using a systematic clinical approach. In our study, we have identified new features and others that were thought to occur only rarely. These include short stature and poor weight gain with preservation of head circumference in nearly all subjects, trismus in 35% and hypospadias in 78% of males. In addition, we describe the frequency of phenotypic features and demonstrate the extreme clinical variability in the largest cohort of AEC individuals reported in the literature thus far. © 2009 Wiley-Liss, Inc.