The prospect of cloning a liver to replace your alcohol-ravaged one, or brain cells to restore your failing memory, is the stuff of dreams. Who could object to making it a reality?
Plenty do, including religious groups that object to the use of foetal tissue, and others who oppose stem-cell research because of its crossover with the technology needed for human cloning.
In the United States (page 68), federal funds may not be used for stem-cell research, which is also forbidden in some states. Things are not going to get easier in election year, and would-be president George W. Bush has substantial debts to the religious right. US stem-cell research will remain in the hands of private industry, which sees immense scope for profit.
In the United Kingdom, this research is likely to proceed rapidly if ethics committees permit it. But researchers must be sensitive to the people for whom it raises issues of conscience.
More significantly, all concerned should realise that although few scientists want to clone humans, building up research and therapeutic capacity using stem cells inherently informs the task of copying human cells at an early stage of development, much as a civil nuclear industry cannot help producing the people and equipment needed to make bombs.
Dolly the sheep happened because scientists wanted to produce therapeutic drugs in bulk, not because they wanted to clone mammals. The public heard about the work only after she was born. In the crucial phase that follows, we need a better-informed awareness of what we are doing, before we do it.