This thesis is dedicated to my grandparents

3.3 Identification and etiopathogenetic study
of a PXE related disorder: unravelling a
common final pathway with PXE
Publication 7
Pseudoxanthoma elasticum-like phenotype with cutis laxa and
multiple coagulation factor deficiency represents a separate
entity.
Olivier M. Vanakker, Ludovic Martin, Dealba Gheduzzi, Bart P. Leroy, Bart Loeys,
Veronica I.Guerci, Dirk Matthys, Sharon F. Terry, Paul J. Coucke, Ivonne
Pasquali-Ronchetti, Anne De Paepe.
J Invest Dermatol 2007;127:581-587
This papers gives a detailed account of the identification of a novel disorder in which
patients initially present with symptoms and signs typical for PXE. During the course of the
disorder, a generalized increase of inelastic skin folds is observed, resembling cutis laxa and
hence highly atypical for PXE. The clinical differences with PXE – among which are a mild
retinopathy and the consistent presence of a clotting deficiency – are discussed, as well as the
particular electronmicroscopical features of this disease.
Through a candidate gene approach, we were able to identify the causal gene for this
disorder as the GGCX gene, coding for an important enzyme in the vitamin K-cycle. These data
gave important insights in the pathogenesis of this PXE-like disorder – implicating vitamin Kdependent
inhibitors of calcification – and would prove to be of great value to gain insights in the
final pathway leading to PXE (publication 8).
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