Sir

Your News story ”Researchers divided over ethics of a ban on cloning“ (Nature 423, 373; 2003), describing the possible lack of ethical grounds for banning safe reproductive cloning, shows the perils of legislating early in the developmental trajectory of a technology. If human reproductive cloning becomes safe, protecting the welfare of cloned persons — who will be as unique and worthy of respect as any other person — will cease to be a strong reason to oppose reproductive cloning.

A more fruitful policy approach would then be to ask whether safe cloning would serve important reproductive or familial needs, and if so, what the impact of allowing cloning in those cases would be. An important distinction in this regard is between cloning to establish a family connection, as might occur in the case of severe gametic infertility, and cloning by fertile persons to choose the genotype of a child. Cloning when infertile to have an otherwise unavailable genetic connection with a child serves a different need and is arguably more deserving of societal respect than cloning by a fertile couple to choose a particular genome.

Whether legal bans are needed if cloning is safe should depend upon a much finer-grained policy analysis than has occurred in the current rush to prohibit all cloning. If safe uses of cloning are not feasible, few responsible practitioners will offer the procedure. Even if cloning can be made safe, few otherwise fertile persons are likely to seek it or have a legitimate claim for it.

Legislating now to ban all cloning carries a high price, both in limiting potential future legitimate uses and in preventing researchers from cloning embryos for stem-cell or genetic-disease research. The possible dangers involved in reproductive cloning are too vague and unrealized to drive national and international policy covering all forms of cloning.