Examples of values from nontransplanted WT and Hbbth-4 heterozygous mice; and from WT and het recipients after transplantation of in vitro PG ES cell derivatives, with 30%–80% ES cell–derived contribution to wbc. wbc data are presented as 103/mm3; rbc, as 106/mm3; hemoglobin (HGB), g/dl; hematocrit (HCT), %; mean corpuscular volume (MCV), fl; mean corpuscular hemoglobin (MCH), pg; mean corpuscular hemoglobin concentration (MCHC), g/dl.