Determine the Frequency of Variants in the GBA/PSAP Genes in Patients With MM or MGUS

Determine the Frequency of Variants in the GBA/PSAP Genes in Patients With Multiple Myeloma (MM) or Monoclonal Gammopathy of Undetermined Significance (MGUS)

No effective specific treatment is currently available for the management of Multiple Myeloma (MM) and Monoclonal Gammopathy of Undetermined Significance (MGUS). A better understanding of the pathophysiological mechanisms would make it possible to propose treatments specifically targeting the deregulated pathways.

This study will characterise the links between rare diseases and complex, chronic diseases. Metabolism can be visualised as a complex network in which the various biomolecules represent metabolic nodes and are linked together by connections. The number of connections at a node influences the effect of that biomolecule on the metabolic network(s) as a whole. If a biomolecule has a large number of connections, altering a metabolic pathway involving it will have an effect that will spread throughout the network. On the other hand, metabolic pathways with a high flux have a major impact on the homeostasis of the network. Thus, alteration of such a metabolic pathway cannot be without consequence: a major alteration could induce a rare hereditary metabolic disease with an early-onset clinic, whereas an alteration with a moderate effect could participate in the pathogenesis of complex diseases, and may open up new therapeutic prospects for these tumour pathologies.

Inclusion Criteria:

• Major patients with multiple myeloma (MM) (defined by clonal proliferation of tumour plasma cells (>10%), presence of a monoclonal peak in serum or urine (excluding non-secretory myeloma) and organ involvement secondary to bone marrow invasion) or with MGUS (defined as bone marrow plasmacytosis of less than 10%, associated with a monoclonal protein of less than 30g/L and no clinical involvement).
• Membership of a social security scheme
• Adult having read and understood the information letter and signed the consent form

Exclusion Criteria:

• Person deprived of liberty by an administrative or judicial decision or person placed under court protection / sub-guardianship or guardianship