Growth and Differentiation of Transplanted W/Wv Marrow

This paper reports new data on the effect of the action of the mutant genes W and W^v on murine hemopoiesis. Our studies demonstrate that the presence of these mutant genes produces: (1) a macrocytic anemia with neither granulocytopenia nor thrombocytopenia; (2) a severe defect in the early stages of hemopoietic repopulation manifested by (a) an apparent block in the differentiation of immature cells into erythroid precursors, and (b) a greatly reduced rate of proliferation of differentiated hemopoietic elements.

These data demonstrate the existence of genetic influence on repopulation and differentiation of transplanted marrow and suggest that severe anemia may result not only from defects in the late stages of erythroid development but also from abnormalities in the early stages of erythroid maturation and hemopoietic repopulation.