1. Dysplastic erythropoiesis, erythrocyte gigantism and giant plurinucleated red cell precursors in the bone marrows of a woman and all 3 of her children are described. All 4 subjects have mild anemia without symptoms therefrom.
2. The changes described are apparently irreversible but do not represent malignant nor agonal change.
3. It is likely that these findings represent an inherited anomaly of erythropoiesis. The nature of the genetic transmission cannot be determined from these studies.
4. We propose the designation familial erythroid multinuclearity to describe this anomaly of red cell production.