Identification of the first deletion in the LRP5 gene in a patient with autosomal dominant osteopetrosis type I.

Abstract

In the last decade, the low-density lipoprotein receptor-related protein 5 (LRP5) gene, coding for a coreceptor in the canonical Wnt signalling pathway, has been shown to play an important role in regulating bone mass and to be involved in the pathogenesis of several bone disorders. Here we describe a patient who presented with a clinical picture of Autosomal Dominant Osteopetrosis type I (ADO I), in whom we could identify the first deletion in the LRP5 gene causing increased bone mass. This mutation caused the in-frame deletion of two amino acids in the fourth blade of the first propeller of the protein, namely the highly conserved glycine at position 171 and the following glutamate residue. In vitro studies suggested that the pathogenic effect of this novel mutation could be due to a decreased inhibition of Wnt signalling by the antagonistic proteins sclerostin and Dickkopf-1, encoded respectively by the SOST and DKK1 genes, in the presence of mutated LRP5. Our results highlight an increasing molecular heterogeneity in LRP5-related bone diseases.

• Authors: Alessandra Pangrazio, Eveline Boudin, Elke Piters, Giuseppe Damante, Nadia Lo Iacono, Angela Valentina D'Elia, Paolo Vezzoni, Wim Van Hul, Anna Villa, Cristina Sobacchi
• Journal: Bone (Bone) Vol. 49 Issue 3 Pg. 568-71 (Sep 2011) ISSN: 1873-2763 [Electronic] United States
• PMID: 21600326 (Publication Type: Case Reports, Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2011 Elsevier Inc. All rights reserved.

Chemical References

• LRP5 protein, human
• Low Density Lipoprotein Receptor-Related Protein-5

Topics

• Base Sequence
• Cell Line
• Female
• Humans
• Low Density Lipoprotein Receptor-Related Protein-5 (genetics)
• Middle Aged
• Molecular Sequence Data
• Mutation
• Osteopetrosis (congenital, genetics, pathology, physiopathology)
• Sequence Deletion