Hemoglobin ontogeny during normal mouse fetal development.

Abstract
Pure populations of large, nucleated erythrocytes derived from yolk sac blood islands were obtained during normal fetal mouse development. Embryonic Hb were present in the cells early in gestation. Later in gestation, an increasing amount of adult Hb was synthesized and accumulated in this population of primitive nucleated erythrocytes, as demonstrated by both biochemical and immunocytochemical techniques.