is a form of ectodermal dysplasia, a group of about 150 conditions characterized by abnormal development of ectodermal tissues including the skin, hair, nails, teeth, and sweat glands. This condition is characterized by the association of anhidrotic ectodermal dysplasia with cleft lip/palate. Other common features include sparse, brittle, and dry hair with alopecia in adulthood together with hypohidrosis (a reduced ability to sweat) and heat intolerance, dental anomalies (hypodontia (absent teeth) , cone-shaped incisors and enamel hypoplasia (thin or absent tooth enamel) and dysplastic (misshapen or absent) nails. Rapp-Hodgkin syndrome is transmitted as an autosomal dominant trait and is caused by mutations in the TP63 gene. Treatment is symptomatic and supportive. A multidisciplinary team of specialists in medical genetics, dermatology, ophthalmology, otolaryngology, audiology, dentistry and prosthodontics, plastic surgery, gastroenterology, and psychiatry is recommended.
Rapp-Hodgkin syndrome has signs and symptoms that overlap considerably with those of ankyloblepharon-ectodermal defects-cleft lip/palate (AEC) syndrome. These two syndromes were classified as separate disorders until it was discovered that they both result from mutations in the same part of the same gene. Most researchers now consider Rapp-Hodgkin syndrome and AEC syndrome to be part of the same disease spectrum. Source: Genetic and Rare Diseases Information Center (GARD), supported by ORDR-NCATS and NHGRI.