British Section of the World Federation of Doctors Who Respect Human Life

Sir - Professor Doug Turnbull confesses that he and his colleagues "don't... want to wait another three years for the law to change" to allow the birth of "babies with three parents" (report, February 5).

Supporters assure us that this is not really cloning but, at most, a benign form of germ-line genetic engineering.

Unfortunately, cloning is exactly what this is: would-be parents produce an early IVF embryo, whose genetic vital parts are then destructively transferred to another woman's ovum. The resulting clone embryo is a distinct individual, whose relation to the original embryo is something like that of twin to twin.

Far from having three parents, the resulting embryo has only a fraction of a true parent: the donor of a partly empty ovum, who contributes part of what a mother normally provides. The child born will realise that her birth required not just an unknown woman's ovum but the destruction of her own identical twin on her social parents' instructions.

There are suspicions that the slightest push will overcome any Government resistance to this procedure. But there is still time for the Government and all MPs to show their awareness of the risks and harms such techniques involve for those conceived and their descendants.

Dr Helen Watt, Director, Linacre Centre for Healthcare Ethics, London NW8