What is the difference between therapeutic and reproductive cloning?
Reproductive cloning involves creating an embryo by nuclear transfer and then implanting it into a uterus and allowing it to establish a pregnancy. This has been achieved for sheep and several other mammalian species. It is not known whether it could be made to work in humans, but the vast majority of researchers in the field are strongly opposed to attempting such an experiment. Many countries and some US states have already enacted legislation that permits therapeutic cloning while prohibiting reproductive cloning. Harvard supports a proposal to enact similar legislation in Massachusetts.
