by University of Cambridge A human embryo cultured in vitro through the implantation stages and stained to reveal OCT4 transcription factor, magenta; GATA6 transcription factor, white; F-actin, green; and DNA, blue. Analysis of patterns of gene expression in such embryos reveals that ACE2, the receptor for the SARS-CoV-2 virus, and the TMPRSS2 protease that facilitates viral...