Even in the more favorable prognostic subtype of CLL cases, defined by the mutational status of the immunoglobulin heavy chain variable region (IGHV) genes in B cells as mutated CLL (M-CLL), high UGT2B17 predicts a poorer outcome relative to those with low UGT2B17 levels [3, 6]. The gene discussed is SLC3A2; the disease is B-cell chronic lymphocytic leukemia.