Erythroid deletion of SETD8, achieved by crossing mice that harbor floxed Setd8 alleles [10] with mice that that express cre-recombinase under the direction of the endogenous erythropoietin promoter, [16] is embryonic lethal by embryonic day 11.5 (E11.5) due to profound anemia [13]. The gene discussed is EPO; the disease is anemia.