PLCG1 and colitis: PLCγ1 conditional knockout mice and PLCγ1f/f [wild type (WT)] littermates developed colon tumors, primarily in the distal to middle segments, using the AOM/DSS protocol (Figure 1B, 1D, 1F, 1G and 1H), consistent with the localization of human colorectal tumors, the most severe consequence of DSS-induced colitis [18].