Figure 2B illustrates that the number of chromosomes per metaphase in the PyV MT/jnk2+/+ tumors was more frequently diploid compared to the PyV MT/jnk2−/− tumors. Each tumor is represented by a specific color (listed as mouse number and number of metaphase spreads counted per tumor in the legend). While aneuploidy was rather common in both groups, it was significantly more frequent in the PyV MT/jnk2−/− tumors. Together, these data are consistent with the conclusion that loss of jnk2 expression increases tumor aneuploidy in this model. The gene discussed is MAPK9; the disease is neoplasm.