First cousins, a male and a female, with a new type of hidrotic ectodermal dysplasia are described. They were each the result of first cousin marriage from the Egyptian Karaite community. They both had partial adontia, conical peg-shaped teeth, fine hair that did not grow long, normal sweating, eversion of lips, and pronounced facial similarity. The male had cleft lip on the right side while the female had a branchial cyst on the left side of the neck. The parents of both the cases were completely normal. The patients had distinct clinical similarity to the condition described by Witkop (1965) as 'Autosomal dominant dysplasia of nails and hypodontia' but the nails were less affected and the mode of inheritance was completely different.