Further evident at ×400 magnification, the strongly PRMT5+ medium-sized tumor blasts in RT LN tumors demonstrate cytology explicitly divergent from CLL LN cases with limited penetrance of small lymphoid cells, indicating these tumors were largely comprised of PRMT5+ large lymphocytes and not small lymphocytes from the tumor microenvironment (Supplementary Fig. 1D). The gene discussed is PRMT5; the disease is B-cell chronic lymphocytic leukemia.