A novel p63 sterile alpha motif (SAM) domain mutation in a Japanese patient with ankyloblepharon, ectodermal defects and cleft lip and palate (AEC) syndrome without ankyloblepharon.
AEC (ankyloblepharon-ectodermal defects-clefting) syndrome is an autosomal dominant ectodermal dysplasia disorder caused by mutations in the transcription factor p63.
However, p63 mutations associated with the ankyloblepharon-ectodermal dysplasia-clefting (AEC) syndrome (Hay-Wells syndrome) were found in the p63 carboxyl-terminal region with a sterile alpha-motif.
In humans p63 mutations are associated with several distinct developmental syndromes. p63 sterile-α-motif domain, AEC (ankyloblepharon-ectodermal dysplasia-clefting)-associated mutations are associated with a high prevalence of orofacial clefting disorders, which are less common in EEC (ectrodactyly-ectodermal dysplasia-clefting) patients with DNA binding domain p63 mutations.
Moreover, we show that transcription of Dlx3 is abrogated by mutations in the sterile alpha-motif (SAM) domain of p63 that are associated with ankyloblepharon-ectodermal dysplasia-clefting (AEC) dysplasias, but not by mutations found in ectrodactylyectodermal dysplasia-cleft lip/palate (EEC), Limb-mammary syndrome (LMS) and split hand-foot malformation (SHFM) dysplasias.
Mutations in sterile alpha motif (SAM) domain of TP63 have been reported to be associated with ankyloblepharon-ectodermal dysplasia-cleft lip/palate syndrome and Rapp-Hodgkin syndrome.
Several ectodermal dysplasia syndromes, including Ectrodactyly-Ectodermal dysplasia-Clefting (EEC) and Ankyloblepharon-Ectodermal Dysplasia-Clefting (AEC) syndromes, are known to result from mutations in the p63 gene.
The third hallmark of the EEC syndrome is orofacial clefting, in particular lip and palate. p63 mutations also cause the other five inherited syndromes: symptoms are overlapping, but each of these diseases has its own characteristic phenotypic features: for instance AEC syndrome (ankyloblepharon-ectodermal defects-cleft lip/palate) has as distinctive feature ankyloblepharon, while mammary glands and nipples hypoplasia are frequent findings in LMS syndrome and in ADULT syndrome (acro-dermato-ungual-lacrimal-tooth syndrome).