Ectodermal Dysplasia 5, Hair/nail Type

Description

Some ectodermal dysplasias are here classified as congenital disorders characterized by abnormal development in 2 or more ectodermal structures (hair, nails, teeth, and sweat glands) without other systemic findings. Ectodermal dysplasia of the hair/nail type is a rare congenital condition characterized by hypotrichosis and nail dystrophy without nonectodermal or other ectodermal manifestations.

Clinical Features

Rafiq et al. (2005) reported ectodermal dysplasia of the hair/nail type in 13 members (8 males; 5 females) over 6 generations of an inbred Pakistani family. Clinical features included micronychia, resulting in highly dystrophic fingernails, anonychia of toenails, thin scalp and body hair, and fine eyebrows and eyelashes.

Inheritance

The transmission pattern of ectodermal dysplasia in the family reported by Rafiq et al. (2005) was consistent with autosomal recessive inheritance.

Mapping

In 13 members of an inbred Pakistani family with an autosomal recessive form of ectodermal dysplasia, Rafiq et al. (2005) performed genomewide linkage analysis of 390 microsatellite markers and mapped the ectodermal dysplasia locus to a 3.92-cM interval flanked by markers D10S1710 and D10S1741 on chromosome 10q24.32-q25.1. Multipoint linkage analysis generated a maximum score of 4.79 in a 6.35-Mb interval between D10S1239-D10S1264.