IKZF1 and neoplasm: Particularly for birds infected with G2M Ikaros Mut, these cohorts had significantly higher probability of developing tumors relative to G2M (Replicate 1 odds ratio of 33, p = 0.0013; Replicate 2 odds ratio of 24, p = 0.0053) as opposed to the birds infected with G2M Ikaros WT, which did not have as large of an increased risk for tumor development relative to G2M controls (Replicate 1 odds ratio 0.92, p = 0.94; Replicate 2 odds ratio 0.20, p = 0.071).