KRAS and T-cell non-Hodgkin lymphoma: Tissue from T-cell lymphomas found in two separate unimmunized Cγ1-Cre KrasG12D mice showed complete Kras allele recombination, suggestive of loss of the wild-type allele, whereas spleen showed a partial recombination pattern consistent with infiltration of the spleen with these same cells (Figure 3B).