Ankyloblepharon-ectodermal defects-cleft lip/palate syndrome (AEC syndrome) is a form of ectodermal dysplasia, a group of conditions characterized by abnormal development of ectodermal tissues including the skin, hair, nails, teeth, and sweat glands. The most common feature is missing patches of skin (erosions) on the scalp, neck, hands, and feet. The skin erosions can lead to infection, scarring, and hair loss. Other features include changes in skin coloring; misshapen or absent fingernails and toenails; malformed or missing teeth; increased sensitivity to heat; hearing loss; cleft lip and/or palate; and other facial abnormalities. This condition is caused by genetic changes in the TP63 gene and is inherited in an autosomal dominant fashion. Rapp-Hodgkin syndrome was classified as a separate disorder until it was discovered that it result from genetic changes in the same part of the TP63 gene. Rapp-Hodgkin syndrome and AEC syndrome are considered to be part of the same disease spectrum.