The present study included the classical blood parameters for HD patients (i.e. urea, creatinine, and phosphorus) as well as representative uremic toxins for each class, i.e. the small water soluble solutes: uric acid, ADMA and SDMA; the middle molecule β2M, and the protein-bound solutes: pCG, HA, IAA, IS, pCS, and CMPF. The gene discussed is B2M; the disease is Huntington disease.