Will it deliver designer babies to the wealthy or eradicate disease among the poor? Stephen Phillips ponders biotechnology's potential to shape our future, Francis Fukuyama (below, left) urges restraint and Gregory Stock (below, right) anticipates a brave new world.
The current biotechnology debateI remains mired at a relatively abstract level about the ethics of procedures such as cloning or stem-cell research," notes Francis Fukuyama in Our Posthuman Future: The Consequences of the Biotechnology Revolution.
Fukuyama's new tome and Gregory Stock's just-published Redesigning Humans: Our Inevitable Genetic Future, aim to bring into focus the potential long-term human applications of biotechnology.
Their widely divergent conclusions have stoked intense debate among US scholars about what a genetically engineered future might look like and the implications of medical and reproductive possibilities opened up by the untangling of human biology.
For Fukuyama, techniques for surveying projected germ line to allow parents-to-be to manipulate DNA in fertilised eggs and bequeath better genes to their children, or, closer at hand, the ability to genetically screen embryos before implanting the "right" one in mothers' wombs, offer glimpses of dystopia.
He argues that "designer babies" raise the spectre of eugenics and threaten to subvert cherished notions of justice and morality.
His views are not academic since he sits on the President's Council on Bioethics and has pledged to dedicate the next few years to devising a strict regulatory regime.
Harold Shapiro, former president of Princeton University and chairman of President Clinton's Bioethics Advisory Commission, and eugenics expert Daniel Kevles, a Yale history professor, praise Fukuyama's book as "challenging and provocative" and a "bold stroke," respectively.
Arthur Caplan, director of the Center for Bioethics at the University of Pennsylvania, agrees with Fukuyama that, left to the market, access to biotechnology will be determined by wealth. Fukuyama infers that inequality of access will breed biological elites bent on subjugating the "genetically unenhanced". But critics say other suggestions appear far-fetched. In a Scientific American article, Kevles singles out the extrapolation that stem cell-enabled lifespan extensions could saddle nations with disproportionate numbers of elderly women whose aversion to military action would undermine the recourse to force in international affairs.
Critics also detect a lack of historicism in some of Fukuyama's concerns. Fears that society will buckle beneath the burden of a genetically enhanced ageing populace ignore the adaptability shown by previous generations to changing longevity, Caplan says, pointing to the "invention of childhood and leisure". He also questions Fukuyama's definition of "human nature", on which he rests his contention that tampering with the code of life presages a post-human future. Fukuyama defines it as "the sum of the behaviour and characteristics that are typical of the human species, arising from genetic rather than environmental factors". This is too nebulous for Caplan, who concludes that many of Fukuyama's reservations are the "overheated mental anxieties of a worrywart".
Kevles argues against the censorious nature of Fukuyama's approach. "Discussion at this stage needs to be kept open because no one has the slightest idea of what kinds of things human germ-line engineering might accomplish."
And he takes issue with the mission Fukuyama has in mind for a proposed watchdog to "discriminate between those technological advances that promote human flourishing and those that pose a threat to human dignity and wellbeing".
"How does he know what fosters human flourishing?" Kevles asks. "Suppose there is a genetic basis for homosexuality - how will you decide whether to foster that gene?"
He believes restrictions in one region will simply force researchers to relocate. Ultimately, he adds, "people will accept technology they find useful and attractive".
Stock, on the other hand, argues that the genetic engineering genie is already out of the bottle and that we should embrace "our inevitable genetic future".
"Our history is not a tale of self-restraintI The question is not whether we will manipulate embryos but when, where and how," he says. Pitting himself against "today's bio-Luddites", Stock, director of the University of California at Los Angeles medical school's program on medicine, technology and society, asks: "Why shouldn't we try to give our children the talents we did not have?"
He acknowledges there will be trial and error - "cautious, informed trialI and as little error as possible" - under the modest monitoring he advocates, but past eugenic abuses argue against monolithic government involvement, he contends. "Government abuse is what we must fear. The chaos of countless individual genetic choices by individual parents is not a threat," Stock says.
Those opposed to the "genetic bazaar where all parents can obtain equivalent talents and potentials for their children" have a vested interest in upholding a status quo wherein their "God-given gifts have raised them above the throng", he adds.
Lee Silver, professor of molecular biology and public affairs at Princeton, hails Stock's courage for expressing convictions many scientists hold in private but are unwilling to voice publicly. But critics concur that a genetically engineered future might not be as benign as Stock suggests. He glosses over the "political problems presented when one part of society has access to technology that other parts do not", Silver says.
The laissez-faire prescription also discounts the possibility of faddish genetic trends, Caplan adds. "It could be freckles one year, large breasts the next and redheads another," he suggests.
Moreover, Stock's expectation that the market will be an immutable agent of change seems a little glib in the face of the blow dealt to powerful commercial interests by public opposition to genetically modified food in Europe, Caplan notes.
Still, other historical precedents endorse Stock's prognosis. "Biological innovations have often been greeted by denunciation - then widely accepted," Kevles says, pointing to artificial insemination by donor, in vitro fertilisation and surrogate motherhood.
Ironically, amid the conservative caste of George W. Bush's bioethics council, Fukuyama, for all his hand wringing, may represent the best hope enthusiasts such as Stock have of some measure of US support for research agendas. While he is opposed to human cloning, he falls short of advocating an outright ban on other lines of inquiry.
But the authors do agree over one issue - that, in Stock's words, continued "focus on the theological implications of laboratory procedures rather than on the results they bring, will greatly weaken our attempt to deal with the approaching challenges".