A Mutation in the Hair Matrix and Cuticle Keratin KRTHB5 Gene Causes Ectodermal Dysplasia of Hair and Nail Type

The study identified a mutation in the KRTHB5 gene, which is responsible for a form of ectodermal dysplasia affecting hair and nails. Researchers studied a large consanguineous family from Pakistan and mapped the disease locus to chromosome 12q12–q14.1. They discovered a homozygous missense mutation, R78H, in the KRTHB5 gene, which resulted in a histidine substitution of a conserved arginine residue. This finding provided the first direct evidence of the molecular pathogenesis of pure hair-nail ectodermal dysplasias.