1. It may be associated with Melkersson Rosenthal syndrome, and hereditary ectodermal dysplasia . 2. Ectodermal dysplasia describes abnormalities of structures derived from the embryonic ectoderm.3. Worldwide around 7, 000 people have been diagnosed with an ectodermal dysplasia condition. 4. Hypohidrotic ectodermal dysplasia ( HED ) is the most common subtype of the disease. 5. The condition, hypohidrotic ectodermal dysplasia , is rare, inherited and incurable. 6. Hypohidrotic Ectodermal Dysplasia Foundation : http : / / www . hedfoundation . org/ 7. Mutations in this gene have been associated with the ectodermal dysplasia / skin fragility syndrome. 8. Like hemophilia, another sex-linked disease, ectodermal dysplasia affects about one in 10, 000 people .----- 9. Ectodermal dysplasia is a vague term, as there are over 170 subtypes of ectodermal dysplasia.10. Ectodermal dysplasia is a vague term, as there are over 170 subtypes of ectodermal dysplasia .