An Ancient Battle Is Playing Out in the DNA of Every Embryo
19th June 2024
For nearly three days after a sperm meets an egg, the human embryo (a tiny, eight-cell blob) is managed by the egg’s genes. On day three, the embryo strips its entire genome naked, freeing itself of maternal control and exposing its genes for activation. Then, says computational biologist Manu Singh, “the army of the dead invades on day four.”