Identification of two novel nonsense mutations in the transglutaminase 1 gene in a Hungarian patient with congenital ichthyosiform erythroderma

Abstract

Congenital ichthyosiform erythroderma (CIE) belongs together with lamellar ichthyosis (LI) to the group of autosomal recessive congenital ichthyoses (ARCI). Mutations in the transglutaminase (TGase) 1 gene (TGM1) have been identified in several families with LI and in some families with CIE. We report a case of CIE with two new nonsense mutations: a C7780G transversion in exon 11 resulting in a premature stop codon at aminoacid residue Y503X and a C8533G transversion in exon 13 leading to a nonsense mutation at S669X. These mutations were also identified hi a heterozygous pattern in the unaffected parents. These two termination-codons result in the translation of a truncated protein at the C-terminal end domain of the TGM 1 molecule. B.C1 monoclonal antibody failed to detect TGase 1 in the patient's skin sample, and TGase activity measured by monodansyl cadaverine-incorporation showed the reduced TGase activity at the distribution of TGase 1 in the epidermis. © Blackwell Munksgaard, 2003.