Ectodermal dysplasia

Ectodermal dysplasia (ED) is not a single disorder but a group of genetic syndromes all deriving from abnormalities of the ectodermal structures.:570 More than 150 different syndromes have been identified. Despite some of the syndromes having different genetic causes, the symptoms are sometimes very similar. Diagnosis is usually by clinical observation, often with the assistance of family medical histories so that it can be determined whether transmission is autosomal dominant or recessive. Worldwide, around 7,000 people have been diagnosed with an ectodermal dysplasia condition. Some ED conditions are only present in single family units and derive from very recent mutations. Ectodermal dysplasias can occur in any race but are much more prevalent in Caucasians than any other group and especially in fair Caucasians. Ectodermal dysplasias are described as 'heritable conditions in which there are abnormalities of two or more ectodermal structures such as the hair, teeth, nails, sweat glands, salivary glands, cranial-facial structure, digits and other parts of the body.'