Refined transcriptional blueprint of human preimplantation embryos

Despite being a biologically fundamental question, the precise timing of lineage specification during human preimplantation development remains elusive. In this issue of Cell Stem Cell, Meistermann et al. (2021) refine our view through time-lapse embryo staging and single-cell sequencing and challenge the concept of a human inner cell mass.

Automated summary

Using time-lapse embryo staging and single-cell sequencing, Meistermann et al. (2021) provide new insights into the precise timing of lineage specification during human preimplantation development and raise questions about the concept of a human inner cell mass.