Similarities of the Erythrocytes in Juvenile Chronic Myelogenous Leukemia to Fetal Erythrocytes

A 4-yr-old boy was studied who showed typical findings of juvenile chronic myelogenous leukemia, including massive hepatosplenomegaly, thrombocytopenia, low leukocyte alkaline phosphatase, and absence of a Philadelphia chromosome. The erythrocytes of the patient exhibited many characteristic features of erythrocytes of newborn infants: the fetal hemoglobin concentration was greatly elevated (72%); the oxygen dissociation curve of the whole blood was displaced to the left of the curve from normal adult blood; the hemoglobin A₂ level and the erythrocyte I antigen titer were reduced; and a structural analysis of the γ-chain of the fetal hemoglobin showed the glycine to alanine ratio in γ-136 to be typical of the neonatal pattern. These findings support the suggestion that juvenile chronic myelogenous leukemia is accompanied by reversion to a fetal pattern of erythropoiesis.