a, Reconstructed embryos (Cwt+Mwt+Pwt, n = 78; Cwt+Mmut+Pwt, n = 74; Cmut+Mwt+Pwt, n = 22) were cultured to 24h, 48h and 96h after spindle transfer, respectively. One representative result of five independent experiments is shown. Scale bars: 20 μm. b, Morphology of Cwt+Mwt+Pwt (n = 44) and Cwt+Mmut+Pwt (n = 38) embryos dissected from E10.5. One representative image from 2-3 independent experiments is shown. Pl, placenta; Em, embryo; YS, yolk sac; EPC, ectoplacental cone. c, Box plots showing enrichment of H3K4me3 and H3K27me3 for regions defined as ‘K4me3-gain/loss domains’, ‘K27me3-gain/loss domains’, in control and Cwt+Mmut+Pwt embryos at early 2C (H3K4me3, n = 1; H3K27me3 n = 1) and 8C (H3K4me3, n = 1; H3K27me3 n = 1). The median of each dataset is shown by center line. The bottom, top edges and whiskers represent the 25th, 75th percentiles and 1.5 times the interquartile range, respectively. P-values (t-test, two sided) are shown. d, Snapshot from UCSC browser showing H3K4me3 enrichment at a maternally imprinted locus in control, Setd2mNull FGO, ST embryos, with gene expression at 8C. e, A model illustrating epigenetic reprogramming in control and mutant FGOs or embryos. In Setd2mNull FGO, H3K27me3 and H3K4me3 ectopically spread to former H3K36me3 territories (Gene1 and Gene2). The aberrant epigenome persists to early 2-cell embryos even in reconstructed embryos with WT cytosol (Cwt+Mmut+Pwt). At 8-cell stage, the aberrant H3K4me3 is largely globally reset to canonical H3K4me3, except for ectopic H3K4me3 at ICR of maternal imprinting genes which persists to 8-cell embryos and is associated with increased expression from maternal allele in Cwt+Mmut+Pwt embryos. Aberrant H3K27me3 is still retained in these Cwt+Mmut+Pwt embryos.