Prenatal diagnosis of X-linked hypohidrotic ectodermal dysplasia by linkage analysis

Christ-siemens-touraine syndrome: case report of 2 brothers

Ectodermal dysplasia is a rare disorder. Christ-Siemens-Touraine syndrome (Hypohidrotic Ectodermal dysplasia (HED)) is a diffuse, non-progressive disease present at birth and involves at least two tissues of ectodermal origin. It is caused by mutation in gene ectodysplasin (EDA, EDA1) located at Xq12-13. Main clinical feature of HED is sparse or absent eccrine gland as well as hypotrichosis, nail, and teeth abnormality with characteristic faces. The absence or diminished activity of sweat gland results in patients having more chances of developing hyperthermia and with intolerance to warm environment. Most do well with simple measures such as wet clothes, air conditioning, wet bands etc. We present cases of two brothers, born of non-consanguineous marriage, who presented to us with complaints of heat intolerance and abnormal facial features.

Hypohidrotic ectodermal dysplasia: prenatal diagnosis by three-dimensional ultrasonography

Ectodermal dysplasia is the term used to describe a group of rare congenital anomalies characterized by abnormal development of 1 or several ectoderm-derived tissues. At least 154 different types, divided into 11 clinical subgroups, have been recognized. Among them, the hypohidrotic type is the most common form, with an incidence of 1 per 10,000 to 1 per 100,000 live births. This condition, originally known as anhidrotic ectodermal dysplasia because of the notable reduction of sweat gland function, is clinically characterized by hypohidrosis, hypotrichosis, and hypodontia. Most cases are inherited as an X-linked recessive trait, with the gene responsible being mapped to Xq12-q13.1. The autosomal recessive and dominant patterns of inheritance have also been documented. Prenatal diagnosis of this condition has been reported previously in high-risk pregnancies on the basis of histologic analysis of fetal skin obtained by second-trimester fetoscopy-guided skin biopsy. DNA-based linkage analysis has also made the diagnosis possible with the use of chorionic villi in the first trimester. In this report, we describe noninvasive prenatal diagnosis of hypohidrotic ectodermal dysplasia in a pregnancy at risk for this condition. The diagnosis was achieved by identification of the distinct facial features at 30 weeks' gestation on three-dimensional (3D) ultrasonography.

A case of hypohidrotic ectodermal dysplasia

Hypohidrotic ectodermal dysplasia (HED) is a rare, hereditary, congenital disease that affects several ectodermal structures. It is characterised by the following: anhidrosis or hypohidrosis, dental abnormalities, hypotrichosis, and a characteristic facies. The face shows prominent frontal bosses, supraorbital ridges and depressed bridges. We experienced a case of hypohidrotic ectodermal dysplasia in a 43-year-old male who had four characteristic features. A skin biopsy from the palm showed a total absence of the eccrine glands. The diagnosis was made on the basis of clinical features and skin biopsy findings.

Mapping around the Xq13.1 breakpoints of two X/A translocations in hypohidrotic ectodermal dysplasia (EDA) female patients

Cellular hybrids were obtained from a t(X;12) identified in a female patient with hypohidrotic ectodermal dysplasia (EDA). This rearrangement had the same Xq13.1 cytogenetic breakpoint as a t(X;9) found in a previously observed EDA patient. A comparative analysis of these two rearrangements with nine probes was performed at the molecular level. These probes could define three subregions: three are proximal, two are distal, and four are between the two breakpoints. These last probes should prove useful for cloning the gene.