Alternative Names
ectodermal defects
Symptoms & Characteristics
Ectodermal dysplasias (EDs) are a group of over 150 conditions that are characterized by the abnormal development of two or more tissues derived from embryonic ectoderm, such as skin, hair, nails, teeth, and sweat glands. Each ED usually involves a different combination of symptoms, but common symptoms can include:
- dry skin that is lacking pigment
- reduced (or absent) ability to sweat
- sparse, fair, brittle hair with baldness
- absent (or diminished) body hair and sparse (or absent) eyebrows and eyelashes
- dental abnormalities (such as absent teeth, malformed teeth, and/or enamel defects)
- reduced (or absent) ability to cry
- reduced (or absent) ability to salivate
- abnormal facial characteristics
- poor body temperature regulation and difficulty controlling fevers
- hearing and vision problems
Other symptoms specific to some EDs include:
- developmental delay/mental retardation
Some EDs are mild, while others are severe. The severity of symptoms can even vary among affected individuals with the same ED. In many cases, affected individuals are not identified until dental, hair, and nail abnormalities become evident during infancy or childhood. Other EDs are apparent at birth.
The following is a list of EDs. Of note, this list does not include every reported ED.
- Acrorenal-Ectodermal Dysplasia-Lipoatrophic Diabetes (AREDYLD) Syndrome
- ADULT Syndrome
- Alopecia-Contractures-Dwarfism Mental Retardation Syndrome
- Ameloonychohypohidrotic Syndrome
- Ankyloblepharon-Ectodermal Defects-Cleft Lip/Palate (Hay Wells syndrome; AEC syndrome)
- Anonychia With Flexural Pigmentation
- Arthrogryposis and Ectodermal Dysplasia
- Autosomal Dominant Anhidrotic Ectodermal Dysplasia with T-cell Immunodeficiency
- Book syndrome (PHC syndrome)
- Cleft Lip/Palate-Ectodermal Dysplasia Syndrome
- Clouston's syndrome
- Coffin-Siris Syndrome
- Congenital Deafness and Onychodystrophy - Autosomal Dominant (DDOD syndrome)
- Congenital Insensitivity to Pain With Anhidrosis (CIPA)
- Cranioectodermal Syndrome
- Curly Hair-Ankyloblepharon-Nail Dysplasia (CHANDS)
- Dermoodontodysplasia
- Dyskeratosis Congenita
- Ectodermal Defect With Skeletal Abnormalities
- Ectodermal Dysplasia, "Pure" Hair-Nail Type
- Ectodermal Dysplasia/Skin Fragility Syndrome
- Ectodermal Dysplasia, Trichoodontoonychial Type
- Ectodermal Dysplasia with Mental Retardation and Syndactyly
- Ectodermal Dysplasia with Severe Mental Retardation
- Ectodermal Dysplasia with Syndactyly
- Ectrodactyly and Ectodermal Dysplasia Without Cleft Lip/Palate
- Ectrodactyly-Ectodermal Dysplasia-Cleft Lip/Palate (EEC) Syndrome
- Ellis-Van Creveld Syndrome
- Focal Dermal Hypoplasia
- Gingival Fibromatosis and Hyperrtrichosis
- Gorlin-Chaudhry-Moss Syndrome
- Growth Retardation-Alopecia-Pseudoanodontia-Optic Atrophy (GAPO syndrome)
- Hallermann-Streiff Syndrome
- Hypohidrotic Ectodermal Dysplasia - X-linked (also known as Christ-Siemens-Touraine Syndrome)
- Hypohidrotic Ectodermal Dysplasia - Autosomal Dominant
- Hypohidrotic Ectodermal Dysplasia - Autosomal Recessive
- Hypohidrotic Ectodermal Dysplasia with Immune Deficiency
- Hypohidrotic Ectodermal Dysplasia with Hypothyroidism and Agenesis of the Corpus Callosum
- Hypohidrotic Ectodermal Dysplasia with Hypothyroidism and Ciliary Dyskinesia (HEDH syndrome)
- Hypomelanosis of Ito
- Hypotrichosis-Osteolysis-Periodontitis-Palmoplantar Keratoderma Syndrome
- Incontinentia Pigmenti
- Ichthyosiform Erythroderma, Corneal Involvement and Deafness
- Ichthyosis Follicularis, Atrichia, and Photophobia Syndrome (IFAP syndrome)
- Ichthyosis with Hypothrichosis
- Johanson-Blizzard Syndrome
- Johnson Neuroectodermal Syndrome
- Kirghizian Dermatoosteolysis
- Leukomelanoderma, Infantilism, Mental Retardation, Hypodontia, Hypotrichosis
- Lymphedema-Hypoparathyroidism Syndrome
- Marshalls Syndrome
- Naefeli Syndrome
- Oculocerebrocutaneous Syndrome
- Oculodentodigital Dysplasia
- Oculoosteocutaneous Syndrome
- Odontoonychodermal Dysplasia
- Onychotrichodysplasia with Neutropenia
- Orofaciodigital (OFD) Syndrome Type 1
- Pachyonychia Congenita
- Papillon-Lefevre Syndrome
- Rapp-Hodgkin Syndrome
- Rosseli-Gulienetti syndrome
- Rothmund-Thomson Syndrome
- Schinzel-Giedion Midface-Retraction Syndrome
- Schopf-Schultz-Passarge Syndrome
- Tetramelic Deficiencies, Ectodermal Dysplasia, Deformed Ears and Other Abnormalities (Odontotrichomelic Syndrome)
- Trichodental Dysplasia
- Trichodentoosseous Syndrome
- Trichodysplasia-Xeroderma
- Trichoodontoonychial Dysplasia
- Witkop Syndrome
Treatment
Treatment for ectodermal dysplasia depends on the symptoms. Early diagnosis, routine surveillance and treatment may help to manage some of the symptoms and sometimes prevent related problems.
How Common Is It?
The frequency of the different EDs varies by population. EDs are most often reported in Caucasians, but have been reported in people of all ethnic backgrounds.
- Some EDs are rare and have only been reported in one or a few families.
- Hypohidrotic ED is the most common ED affecting about 1 in 17,000 people worldwide.
Genetics & Inheritance
The different EDs are caused by mutations in different genes and have different modes of genetic inheritance.
- Some EDs have autosomal dominant inheritance, which means that having a mutation in a single gene copy is sufficient to cause disease. An affected person has a 50% chance with each pregnancy to have an affected child. Some people with autosomal dominant ED have no history of the condition in their family, and their condition is caused by new (sporadic) mutation.
- Some EDs have autosomal recessive inheritance, which means that two mutations are necessary to cause disease, one from each parent. Both parents of an affected person are always both obligate carriers (each have only one mutation). Two carriers have a 25% chance with each pregnancy to have an affected child, but typically do not have symptoms themselves.
- Some EDs have X-linked recessive inheritance. A condition is considered X-linked if the mutated gene that causes the disorder is located on the X chromosome, one of the two sex chromosomes. In males (who have only one X chromosome), one altered copy of the gene in each cell is sufficient to cause the condition. In females (who have two X chromosomes), a mutation must be present in both copies of the gene to cause the disorder. As such, males are affected by X-linked recessive disorders much more frequently than females. A striking characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons. In X-linked recessive inheritance, a female with one altered copy of the gene in each cell is called a carrier. In some EDs, female carriers experience some features of the condition.
The genetics of some EDs are not yet identified or adequately classified.
A genetic consultation with a trained genetic professional is important for a complete evaluation, accurate diagnosis, as well as discussion of the benefits and limitations of testing and recurrence risk.
Genetic Testing
Clinical genetic testing for some ectodermal dysplasias may be available through an in person genetic consultation for people who are considered at risk. Use our find a genetic professional directory to locate a trained genetic professional in your area.
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