title: A glutamine insertion in the 1A alpha helical domain of the keratin 4 gene in a familial case of white sponge nevus.
abstract: White Sponge Nevus (WSN) is a rare, autosomal dominant disorder that predominantly affects noncornified stratified squamous epithelia. Clinically, it is characterized by the presence of soft, white, and "spongy" plaques in the oral mucosa. The characteristic histopathologic features are epithelial thickening, parakeratosis, and vacuolization of the suprabasal layer of oral epithelial keratinocytes. Mutations in keratin 4 (K4) and keratin 13 (K13) genes have already been demonstrated to be responsible for WSN; the identification of new keratin mutations in a stratified squamous epithelia closely related to epidermis is of relevance for the understanding of the biochemistry of intermediate filaments, and for genotype phenotype correlations. In this study we investigated a 27-y-old, female Italian patient, affected by white asymptomatic oral plaques. Sequence analysis revealed a 3 bp (ACA) heterozygous insertion localized in the helix initiation motif of the 1A alpha helical domain of K4. We report this new K4 gene mutation and describe an amino acid insertion, in the 1A domain, responsible for a keratin disease.
authors.affiliation: Biochemistry Laboratory, IDI-IRCCS, c/o Department of Experimental Medicine, University of Rome "Tor Vergata", Rome, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Terrinoni
authors.forename: E
authors.initials: E
authors.lastname: Candi
authors.forename: S
authors.initials: S
authors.lastname: Oddi
authors.forename: T
authors.initials: T
authors.lastname: Gobello
authors.forename: D B
authors.initials: DB
authors.lastname: Camaione
authors.forename: C
authors.initials: C
authors.lastname: Mazzanti
authors.forename: G
authors.initials: G
authors.lastname: Zambruno
authors.forename: R
authors.initials: R
authors.lastname: Knight
authors.forename: G
authors.initials: G
authors.lastname: Melino
mesh_terms: D000328:Adult; D004252:DNA Mutational Analysis; D004251:DNA Transposable Elements; D005192:Family Health; D005260:Female; D005973:Glutamine / Q000235:genetics*; D006222:Hamartoma / Q000235:genetics*; D006801:Humans; D007633:Keratins / Q000235:genetics*; D009059:Mouth Diseases / Q000235:genetics*; D009061:Mouth Mucosa; D010375:Pedigree; D017434:Protein Structure, Tertiary
chemical_list: D004251:DNA Transposable Elements; D005973:Glutamine; D007633:Keratins