Erythroid lineage-restricted expression patterns of Cited2 and Sox6. (A) Affymetrix intensity indicates erythroid lineage–restricted expression of the transcription factors Cited2 and Sox6. (B) qPCR quantitation of Cited2 and Sox6 expression in primitive basophilic erythroblasts from E10.5 blood and definitive basophilic erythroblasts from adult BM. (C) In situ hybridization reveals Cited2 expression in primitive erythroid cells within the blood islands of the E9.5 yolk sac (left) and Sox6 exon 1E expression in the E15.5 fetal liver.