When President Bush convened his advisory panel on bioethics in January, he told those of us serving on it to engage in that age-old technique of intellectual exploration called debate. ''That's what I want,'' he said. ''You haven't heard a debate until you have heard Colin Powell and Don Rumsfeld go at it.''

So it was a surprise when, on April 10, the president announced his decision to ban cloning of all kinds. His opinions appeared fully formed even though our panel has yet to prepare a final report and will be voting on the crucial point of biomedical cloning -- which produces cells to be used in researching and treating illnesses. While it is true that the president's position is one held by some of the members of the panel, not all agree.

Most people are now aware that medical scientists put cloning in two different categories. Biomedical cloning is distinct from reproductive cloning, the process by which a new human being might be grown from the genetic material of a single individual. At this point, no scientist or ethicist I know supports reproductive cloning of human beings. The debate is solely about biomedical cloning for lifesaving medical research.

Scientists prefer to call biomedical cloning somatic cell nuclear transfer, because that is what it is. Any cell from an adult can be placed in an egg whose own nucleus has been removed and given a jolt of electricity. This all takes place in a lab dish, and the hope is that this transfer will allow the adult cell to be reprogrammed so that it will form a clump of approximately 150 cells called a blastocyst. This will be harvested for the stem cells it contains.