Hypohidrotic ectodermal dysplasia caused by an intragenic duplication in EDAR
Lise Graversen1, Mette Sommerlund2, Casper Kruse3
1Department of Clinical Genetics, Aarhus University Hospital, Olof Palmes Allé 49, 8200 Aarhus N, Denmark.
European Journal of Medical Genetics
|October 30, 2024
Summary
Hypohidrotic Ectodermal Dysplasia (HED) is a rare genetic disorder. This study identifies a novel EDAR gene duplication as the cause of HED and mammary gland aplasia in a patient.
Area of Science:
- Genetics
- Developmental Biology
- Human Physiology
Background:
- Hypohidrotic Ectodermal Dysplasia (HED) is characterized by hypotrichosis, hypohidrosis, and hypodontia.
- Pathogenic variants in the EDAR gene cause 10-15% of HED cases, typically missense or nonsense mutations.
Observation:
- A patient presented with classic HED symptoms and mammary gland aplasia.
- Genome sequencing revealed a de novo, tandem duplication within the EDAR gene in the affected individual.
Findings:
- The identified intragenic EDAR duplication is the first reported cause of HED of this type.
- The duplication likely results in an altered EDAR protein exerting a dominant negative effect.
Implications:
- This discovery expands the known spectrum of genetic mutations causing HED.
- Understanding novel EDAR variants aids in diagnosing and potentially managing HED and related developmental abnormalities.
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