AbstractThe hemoglobins synthesized by the pluripotent K‐562 leukemia cell line of human origin after induction with hemin have been isolated by DEAE‐cellulose chromatography and characterized by electrophoresis, high pressure liquid chromatography, and a radio‐immunological assay. Six hemoglobin zones have been observed with the following likely compositions. Zone 1: α2ϵ2, or Hb Gower‐2; zone 2: ζ2ϵ2, or Hb Gower‐1; zone 3: ζ2γ2, or Hb Portland‐I; zone 4: Hb F, or α2γ2; zone 5: a mixture of acetylated Hb Portland‐I and Hb F; zone 6: Hb Bart's, or γ4. The embryonic Hbs (zones 1, 2, and 3) constituted 50%–75% of the total Hb present; the quantities varied from one experiment to the other. Both Hb Gower‐1 and Hb Gower‐2 were present. The γ chain was heterogeneous and contained theGγ,AγI, andAγTtypes in a ratio of about 4:2:1, indicating a heterozygosity for the Ile → Thr substitution at position γ75. The methodology used can be applied for additional studies evaluating quantitative changes in Hb