MYC and Splenomegaly: As in Mock/Myc mice, FLIPL/MYC mice appeared to have a latency period before development of splenomegaly (average spleen weight at 5 weeks after transplantation, 237 mg for FLIPL/MYC compared to 236 mg for Mock/MYC and 138 mg for Mock/Mock recipient mice) (Figure 3).