To be able to evaluate the predictive value of glycosylated ferritin as a predictive marker of hepatic iron stock in dialysis patients, we need to validate these results with a cohort of healthy volunteers.

This biological collection will include a sample of 2 dry tubes and 2 EDTA tubes. A haematological assessment (CBC, platelets, reticulocytes, Chr (hemoglobin content of reticulocytes), TP-INR, AST, ALT, GGT), measurement of biological markers of iron metabolism (ferritin, serum iron, CRP, transferrin, soluble receptors transferrin, transferrin saturation coefficient) as well as a creatinine assay to validate the normality of renal function in healthy volunteers (GFR established from the MDRD formula), a complete ionogram and a phosphocalcic balance being given the interactions in the dialysis patient (but also in normal subjects) between iron metabolism and phosphocalcic metabolism (calcemia, phosphoremia, PTH, 25OHD3, 1,25OH2D3) will be performed.

We will also study the links between iron overload in dialysis patients and the modulation of the synthesis of parathyroid hormone (intact PTH), FGF23, alpha Klotho and sclerostin.

Inclusion Criteria:

• Informed consent
• Age over 18 years old
• Healthy volunteers
• Having given their informed consent in writing
• Absence of current pathology
• No current treatment (except contraception)

Exclusion Criteria:

• Refusal of consent or absence of signature
• Minor, subject protected by law, (guardianship or curatorship, administrative protection measure)
• Pregnant woman, parturient
• Subject suffering from a condition liable to modify his blood parameters