D2HGDH and diffuse large B-cell lymphoma: All D2HGDH mutations found in DLBCL target conserved residues and cluster either at the point of D2HGDH contact with its co-factor, FAD, or in the less well-characterized carboxy (C)-terminal region, a distribution similar to that found in patients with D-2-HGA (Fig. 1b,c)25.