Epidermolysis bullosa simplex: evidence in two families for keratin gene abnormalities.

Epidermolysis bullosa simplex (EBS) is characterized by skin blistering due to basal keratinocyte fragility. In one family studied, inheritance of EBS is linked to the gene encoding keratin 14, and a thymine to cytosine mutation in exon 6 of keratin 14 has introduced a proline in the middle of an alpha-helical region. In a second family, inheritance of EBS is linked to loci that map near the keratin 5 gene. These data indicate that abnormalities of either of the components of the keratin intermediate filament heterodipolymer can impair the mechanical stability of these epithelial cells.