Δ+6 kb enh mice have a complete block in terminal granulopoiesis. (A) Genotyping primers flanking the guide RNA target sequences (red rectangles) generate an amplicon of 410 bp from the WT allele (P1/P2) and an amplicon of 365 bp from the targeted allele (P1/P3). (B) Representative PCR analysis shows genotyping of WT mice (+/+), heterozygous Δ+6 kb enh mice (+/Δ), and homozygous Δ+6 kb enh mice (Δ/Δ). Representative flow cytometric analysis of peripheral blood (C) and bone marrow (D) of WT, heterozygous, and homozygous Δ+6 kb enh mice using granulocyte-specific markers (Gr1 and CD11b). Proportion of mature granulocytes in peripheral blood (E) and bone marrow (F) of WT, heterozygous, and homozygous mice. qRT-PCR (G) and immunoblot (H) for Cebpe and Ltf expression in WT (+/+) and Δ+6 kb enh mice (Δ/Δ). ****P < .0001, ***P < .001, **P < .01, *P < .05.