Sperm and scrambled eggs

A newspaper obituary not long ago revealed that its subject was believed to have been both the son and grandson of the lecherous monarch, Edward VII. (Work it out for yourself.) But this is as nothing to the conundrums that Lee Silver sets out in his mesmerizing vision of our genetic future. Within weeks of the eruption of Dolly the sheep into the pages of Nature — and regardless of the doubts about whether she really originated from an adult cell — a company sprang into being in the Bahamas, with a web site offering a human cloning service at $200,000 a throw. Any woman will one day be able to give birth to a little twin sister whose true parents will be her grandparents. Or she will have the option to bring forth a small replica of, for instance, William Shockley, the eugenically minded physics Nobel laureate, who set up a sperm bank to enrich the race with his genes and those of others with similar intellectual and moral virtues. The guardians of public morality may rail and the Church threaten hellfire, but, says Silver, the free market will prevail: you cannot stand between an affluent citizenry and its urgent desires. Surrogate motherhood and in vitro fertilization (IVF) were both denounced by the bien-pensants, and in America surrogacy is still illegal in some states of the Union; but it is freely offered in others and commonplace elsewhere. By 1994, Silver tells us, there were already 150,000 IVF babies in the world and public opinion had come round. In Britain, artificial insemination of virgins was condemned in fierce terms by members of the parliamentary Conservative party. “One virgin birth for eternity is enough,” said the chairman of the party’s health committee, Jerry Hayes. And the ineffable Dame Jill Knight declared that it was “difficult to imagine a more irresponsible act than to assist a woman to have a child in this highly unnatural way.” Alert readers of the British press may remember that Dame Jill also made a characteristically trenchant contribution to the debate about the freezing of embryos: as a housewife she knew how hard it was to make a pie out of pastry deep-frozen for more than six months. The arguments by philosophers and theologians have not always been any better informed. When the decision was taken to destroy frozen embryos (“orphan embryos”, as a politician called them) in Australia the Catholic Church inveighed against this “prenatal massacre.” Priests and rabbis have asserted that cloning cannot create a soul. Silver counters by asking how many cells are required to qualify for possession of this essence. One can already divide a small cluster of embryo cells taken from a mouse and generate identical multiplets, as of course happens all the time in nature. Do twins or triplets then have only one soul to go round? And, when cloning from an adult cell becomes a workable proposition, will the Vatican urge believers to take care not to shed skin cells, which after all have nuclei, each with the potential to develop into a cloned baby? It is all too reminiscent of those celebrated theological wrangles about what happens when cannibals who have converted to Christianity come up, together with their martyred victims, for bodily resurrection on the Last Day, or whether angels can fly from one place to another without traversing the intervening space. Reprogenetics, as Silver calls it, will no doubt sustain a new breed of mediaeval schoolmen and Talmudic scholars (to say nothing of m’ learned friends at the bar) in the years ahead. Worse, of course, is to come. Eggs develop early in the life of the female fetus and so can be harvested after a miscarriage or abortion. They can be fertilized and develop into children who will eventually have to learn that their mothers were aborted fetuses. Or again, sperm precursor cells can be extracted from a male fetus, and could, if the results of animal experiments are any guide, be implanted into the testis of, say, a mouse, where they will mature and give rise to human sperm. (Indeed, it was announced recently that such a programme is already planned in Australia.) There is then the alluring prospect of progeny from fetal mating in the Petri dish. In the slightly remoter future Silver envisages designer babies, modelled on a gene profile compiled by the parents. The geneticists will here play the part of the good fairy and ensure that the child comes into this harsh world equipped with resistance to say AIDS, cancer and Alzheimer’s disease, with an athletic physique and an aptitude for the violin or for theoretical physics. And why not, says Silver: middle class parents already spend untold sums to give their offspring social and professional advantages. Conversely, there has, I understand, already been one attempt by a young man in the R296 Current Biology, Vol 8 No 9