Monoclonal gammopathy of undetermined significance (MGUS) is the requisite precursor to multiple myeloma (MM). a malignancy of antibody-producing plasma B-cells. The genetic basis of MGUS and its progression to MM remains poorly understood. C57BL/KaLwRij (KaLwRij) is a spontaneously-derived inbred mouse strain with a high frequency of benign idiopathic paraproteinemia (BIP). https://www.roneverhart.com/OTTO-CAP-5-Panel-Mid-Profile-Mesh-Back-Trucker-Hat-OTTO-32-285/