Ichthyosis bullosa of Siemens resulting from a novel missense mutation near the helix termination motif of the keratin 2e gene

Ichthyosis bullosa of Siemens (IBS) is an autosomal dominant disorder of ke ratinization. It is characterized by a mild epidermolytic ichthyosis which tends to localize to the flexures. Affected individuals are born with wides pread blistering, which develops into large hyperkeratotic plaques over the extremities. Mutations in the K2e gene cause epidermolytic hyperkeratosis confined to the upper spinous and granular layers, as observed in IBS. In t his report, we describe a novel mutation in the keratin 2e gene in a four-g eneration IBS kindred of German ancestry The mutation resides within the 2B helix termination motif of the keratin 2e gene, and extends the body of ev idence implicating keratin re gene mutations in IBS.