Study of DNA Copy Numbers Variations and Gene Expression Profile of Bone Marrow Plasma Cells From MGUS and SMM.

Inclusion Criteria:

* Patients aged from 18 to 70 years
* Written informed consent
* One of the following three criteria:

  * Recently diagnosed IgG or IgA monoclonal gammopathy without clinical or biological features of malignant hemopathy
  * IgG or IgA MGUS regardless the date of the diagnosis
  * SMM regardless the date of the diagnosis
* Normal blood count, creatininemia and calcemia \*
* Bence-Jones proteinuria below 1g/24 hours
* Absence of bone pain
* No clinical or biological features of amyloidosis
* No recurrent episode of infection (more than 2 infections requiring antibiotics in the previous 6 months) \* In case of abnormal blood count, renal failure or hypercalcemia, patients may be included if an intercurrent cause is identified (for example anemia associated with iron deficiency)

Diagnostic criteria for MGUS:

* Monoclonal component concentration below 30 g / l AND
* Bone marrow plasmacytosis below 10%
* Bence-Jones proteinuria below 1g/24 hours
* Normal blood count, creatininemia and calcemia \*
* Absence of bone lesions on conventional bone radiographies
* No clinical or biological features of amyloidosis
* Absence of hyperviscosity syndrome
* No recurrent episode of infection (more than 2 infections requiring antibiotics in the previous 6 months) \* In case of abnormal blood count, renal failure or hypercalcemia, patients may be included if an intercurrent cause is identified (for example anemia associated with iron deficiency)

Diagnostic criteria for SMM:

* Monoclonal component concentration greater than 30 g / l AND / OR
* Bone marrow plasmacytosis greater than 10%
* Bence-Jones proteinuria below 1g/24 hours
* Normal blood count, creatininemia and calcemia \*
* Absence of bone lesions on conventional bone radiographies
* No clinical or biological features of amyloidosis
* Absence of hyperviscosity syndrome
* No recurrent episode of infection (more than 2 infections requiring antibiotics in the previous 6 months) \* In case of abnormal blood count, renal failure or hypercalcemia, patients may be included if an intercurrent cause is identified (for example anemia associated with iron deficiency)

Exclusion Criteria:

* Patients younger than 18 years
* Patients older than 71 years
* IgM monoclonal gammopathy (regardless of diagnosis)
* Monoclonal gammopathy associated with hematologic malignancies (multiple myeloma, chronic lymphocytic leukemia, ...)
* Patients with chronic liver disease, autoimmune or neoplastic disease for less than 5 years
* Active viral hepatitis B or C
* HIV seropositive patient
* Pregnant woman
* Breastfeeding woman