Professor Ian Wilmut cloned a ewe he named Dolly using a nuclear transfer method whereby stem cells are produced by inserting adult DNA into enucleated embryos and cloning the embryo.
Wilmut decided not to pursue a license to clone human embryos following new research by a Japanese team into coaxing stem cells from the skin cells of mice, The Telegraph said Saturday.
The nuclear transfer method of stem cell production outraged the pro-life lobby over the destruction of embryos and concerns about cloning humans.
Wilmut said he embraced the new Japanese method over the nuclear transfer method because it evoked fewer ethical issues and provided a greater embryonic yield.
Therapy employing harvested stem cells offers medically significant breakthroughs in the treatment of diseases such as Parkinson's Disease.