Developmental potential of human embryos following CRISPR-Cas9-mediated genome editing. (A) Developmental comparison of ICSI-CRISPR-generated human embryos against control embryos. POU5F1 edited embryos exhibited increased developmental arrest starting from eight-cell stage. Chi-squared test (P = 0.0439) revealed a significant difference between the developmental rates in CRISPR-ICSI (n = 101) and control embryos (n = 33). (B) Brightfield images of the generated POU5F1-null human blastocysts and the corresponding fragment analysis results, confirming the editing of the targeted locus. (C) Immunofluorescence analysis for POU5F1 (Red), SOX17 (Green), and DAPI (Blue) at 6.5 dpf.