Official definition of human embryonic stem cells widened in US

The official definition of human embryonic stem cells in US National Institutes of Health guidelines is to be broadened from those ‘derived from the inner cell mass of blastocyst stage human embryo’ (ie. from embryos that have reached the blastocyst stage at four or five days old, 70-100 cells), to include also those derived from earlier stage embryos. This changes none of the ethical requirements in the guidelines" but was prompted by an application from a commercial source to list cell lines derived from eight-cell stage embryos, and will make some commercial and academic research programmes potentially eligible for government funding. PHG Foundation