Embryo development: Some cells are more equal than others even at four-cell stage

Genetic ’signatures‘ of early stage embryos confirm that our development begins to take shape as early as the second day after conception, when we are a mere four cells in size, according to new research. Although they seem to be identical, the cells of the two day-old embryo are already beginning to display distinct differences. (Mehr in: Cancer News — ScienceDaily)