Funding sources This work was supported by Vlinderkind (Butterfly Child) Foundation.
CLINICAL AND LABORATORY INVESTIGATIONS
Junctional epidermolysis bullosa of late onset explained by mutations in COL17A1
Article first published online: 25 MAY 2011
© 2011 The Authors. BJD © 2011 British Association of Dermatologists
British Journal of Dermatology
Volume 164, Issue 6, pages 1280–1284, June 2011
How to Cite
Yuen, W.Y., Pas, H.H., Sinke, R.J. and Jonkman, M.F. (2011), Junctional epidermolysis bullosa of late onset explained by mutations in COL17A1. British Journal of Dermatology, 164: 1280–1284. doi: 10.1111/j.1365-2133.2011.10359.x
Conflicts of interest None declared.
- Issue published online: 25 MAY 2011
- Article first published online: 25 MAY 2011
- Accepted manuscript online: 5 APR 2011 06:47AM EST
- Accepted for publication 19 February 2011
Background Junctional epidermolysis bullosa of late onset (JEB-lo) is a rare disease characterized by blistering of primarily the hands and feet starting in childhood. The pathogenesis remains unclear.
Objectives To clarify the pathogenesis of JEB-lo.
Methods Two patients with JEB-lo, a brother and a sister, were examined using electron microscopy (EM), immunofluorescence (IF) antigen mapping and molecular analysis.
Results We found subtle changes in IF antigen mapping and EM. The most remarkable changes were loss of the apical-lateral staining of monoclonal antibodies (mAbs) against type XVII collagen (Col17), and a broadened distribution of mAb staining against the ectodomain of Col17, laminin-332 and type VII collagen. Mutation analysis of COL17A1, encoding Col17, showed a compound heterozygosity for a novel mutation c.1992_1995delGGGT and the known mutation c.3908G>A in both patients. The deletion c.1992_1995delGGGT results in a premature termination codon and mRNA decay, leaving the patients functionally hemizygous for the missense mutation c.3908G>A (p.R1303Q) in the noncollagenous 4 domain of Col17.
Conclusions JEB-lo is an autosomal recessive disorder caused by mutations in COL17A1, and subtle aberrations in EM and IF antigen mapping are clues to diagnosis.