For instance, the heavy chain that is overproduced tends to be associated with variations in clinical presentation (e.g., IgD-myeloma usually presents with more aggressive disease and severe complications13), prognosis (e.g., IgA-myeloma is associated with worse prognostic outcomes compared to IgG-myeloma14), complications and clinical monitoring (e.g., tracking IgA versus IgG over time). This evidence concerns the gene CD79A and plasma cell myeloma.