|Disease group||Ectodermal Dysplasia|
|DISEASE NAME||ADULT SYNDROME|
|Gene (s)||p63 (603273)|
ADULT syndrome is a rare autosomal dominant disorder characterized by ectrodactyly (congenital abnormality involving the absence of some fingers or toes), excessive freckling, nail dystrophy, lacrimal duct abnormalities, hypoplastic breasts/nipples and hypodontia. An association with p63 gene mutations was first described by Duijf et al in 2002. Mutations in this transcription factor have also been identified in other ectodermal dysplasia syndromes including AEC (ankyloblepharon-ectodermal dysplasia-clefting; Hay Wells; OMIM 106260) syndrome, EEC (ectrodactyly, ectodermal dysplasia, cleftting; OMIM 129900) limb-mammary syndrome (OMIM 603543), split-hand split-foot malformation syndrome (OMIM 605289) and, most recently, Rapp-Hodgkin syndrome (OMIM 129400).
Infants are born with ectrodactyly and variable ectodermal dysplasia features. Individuals commonly have widespread dry, atrophic and eczematous skin, nail dystrophy and hypodontia. Hair may be sparse, coarse, wiry and difficult to comb. Excessive freckling may be present as well as lacrimal duct abnormalities and breast/nipple hypoplasia.
Many affected individuals have been found to have mutations within the p63 gene, with a hotspot mutation occurring within the DNA binding domain of the gene at the R298 residue.The p63 gene is a p53 homolog, and is an important transcription factor in the development of normal skin and ectodermal structures.
Diagnosis is usually made by assessment of the clinical features either at, or soon after birth. Genomic DNA should be analysed for a p63 gene mutation in order to help confirm the diagnosis and assist with genetic counselling. No other diagnostic tests are available at present.
The management of the ADULT syndrome requires expertise from various medical and surgical specialties. Limb deformities may be partially corrected by surgical procedures and dental treatment is extremely important as many require successive dentures as a child with addition of dental implants and bridges later in adult life. Topical emollients are required to treat dry, eczematous areas of skin and many affected individuals require ophthalmological review regarding lacrimal duct abnormalities.