Human Cloning
... is not new technology. This technology has been used since the early 1960s to answer the question of whether the genetic material of differentiated cells from adult animals is irreversibly modified. Nuclear transfer experiments, first performed in amphibians in the 1960s, in mice in the 1970s, in sheep in the 1980s, and in monkeys in the 1990s have provided evidence that fully differentiated somatic cells retain all the genetic material of the early embryo, and that differentiation is almost entirely achieved by reversible changes in gene expression (Rossant 1997, Wilmut et al. 1997). The nuclear transfer technology that produced Dolly is not new to Ian Wilmut and his group in Scotland, either. They have been studying the control of cell development for over ten years, and just last year published a report of the first mammal to be cloned from an established cell line (Campbell et al. 1996). Their major contributions to this area of research are (1) the complete genetic material from an adult mammalian cell has been used in the development of a new individual for the first time; and (2) donor cells, induced to exit the growth phase and become quiescent before being used for nuclear transfer, are more susceptible to reprogramming by the recipient egg cell and result in the normal development and birth of cloned offspring (Campbell et al. 1996, Wilmut et al. 1997). In order to fully evaluate the issues that nuclear transfer cloning raises, the NBAC requested input from a wide cross-section of the scientific community. Various scientific societies and professional associations (hereafter “societies”) were asked fo...