Ectodermal Dysplasia - A Family Study

Abstract

Ectodermal dysplasias (ED) are group of genetically heterogenous conditions that are characterized by abnormal development of ectodermal structures. The most affected structures are teeth, skin and its derivatives (hair, sweat glands) along with other ectodermal structures. The purpose of this work was to present the family with four boys affected with ED. We described the clinical report of male infant (affected twin) aged two months and his older brothers with absence of eyebrows and eyelashes, saddle nose, dry flaky skin, rare thin blond hair, and large number of dental anomalies with pathohistological-skin positive analysis for ectodermal dysplasia. Only a few abnormally formed teeth erupted (microdontia and conical teeth) and at the later then average age. Radiographic examination confirmed previous clinical findings and determined taurodontism of the molar teeth. They also presented pseudoprognathism of the mandible due to micrognathism of the maxilla. Based on the positive family history (two older brothers), clinical picture and pathohistological findings of the skin we concluded that the child (and his twin brother) were also affected. EDA gene missense mutation, Ala349Thr (GCA --> ACA), was responsible for the condition of observed family. Hair hypotriyhosis, brittle, scanty hair, absent or scanty eyelashes and eyebrows, blonde, fine scalp hair, as minor clinical signs at grandmother and only scanty eyelashes at mother were observed. Mutation analysis in families with X-linked ED help in genetic counseling, prenatal diagnosis, and confirmation of carrier status.