A variety of regimens were utilized on KMOE cells to maximally raise globin mRNA levels for the purpose of improving the usefullness of this line for globin gene studies. Steady-state mRNA levels of embryonic (ϵ), fetal (γ) and adult (β) globin genes were assayed by the S1-nuclease protection method before and after exposure to inducing compounds. Exposure of KMOE cells to cytosine arabinoside and hemin leads to over 20-fold increases inβ- andγ-globin mRNA steady-state levels, and an over 60-fold increase inϵ-globin mRNA level. Exposure to cytosine arabinoside alone inducedβ- andϵ-globin but notγ-globin gene expression. Theα-like globin genes (ζandα) were also monitored but found to be poorly expressed and not significantly inducible. The presence ofϵ-globin mRNA and the lack ofα-globin mRNA distinguishes this line, KMOE-EL, from the KMOE sublines previously described.