The paper describes a treatment, optimized for vitrification, manipulation medium and developmental stage, which
generates normal embryos with a low carry - over of less than 2 % in the vast majority.
Embryonic stem (ES) cells are karyotypically
normal,
embryo - derived cell lines that are pluripotent, i.e. capable of
generating all the cell types of the future organism, but not the extra-embryonic lineages.