A leap of faith for genetics

The vote last week in the British Parliament to permit mitochondrial transfer treatments during in vitro fertilization (IVF) was a watershed moment in the evolution of our species.

This procedure allows doctors to replace diseased mitochondria — the powerhouses of our cells — with healthy donor mitochondria in the eggs or early-stage embryos of prospective mothers. Although the genes contained in our mitochondria only account for less than 0.2 percent of our total genome, this treatment technically results in babies with three genetic parents.

Coming after more than three years of careful study and public outreach, the vote in the House of Commons puts the United Kingdom on a path to becoming the first country in the world to authorize this type of human genetic engineering. (The provision must now move to the House of Lords, where its passage is almost certain.) For the thousands of British women carrying mitochondrial genetic defects, the vote was a godsend that has the potential to spare their future children needless suffering and even premature death.

In the United States, mitochondrial transfer is being treated as a regulatory matter by the Food and Drug Administration. Although this approach might make the procedure available to parents more quickly than would a broader public dialogue, the stakes are too high for this to be a regulatory matter alone. The United States should follow Britain's lead and begin a national conversation about mitochondrial transfer and the future of human genetic manipulation.

After roughly 4 billion years of evolution by natural selection, we are on the verge of taking active control of our evolutionary process. In clinics throughout the world, gene therapies are being deployed to treat disease, and women undergoing IVF are using a process called preimplantation genetic diagnosis (PGD) to screen early-stage embryos for single-gene mutations such as those that cause Huntington's disease and cystic fibrosis.

Because each cell extracted during PGD contains an embryo's full genome, the same process used to screen out genetic disease can also provide a great deal of information about other traits.

As personalized medicine ensures that more of our genomes will be digitized, and as improvements in computing power and sequencing dramatically reduce the speed and cost of analyzing our genomes, including to predict complex traits such as height and the genetic component of intelligence, women undergoing IVF will have far more information when choosing which fertilized eggs to implant.

As these processes unfold and gain social acceptance, governments and insurers will have strong incentives to encourage the use of IVF and embryo screening and selection to avoid what may come to be seen as preventable, and unnecessarily costly, genetic diseases. Over time, this could lead to the end of sex as a means of procreation among all but the least advantaged and most ideologically motivated people. (Spoiler alert: Sex will continue to thrive for its many other virtues.)

This transformation will terrify many people and raise legitimate, fundamental questions. Why should we focus so much on genes when we know that much of our identity comes from other factors? Are we confident enough to meddle with a system, evolved over billions of years, that we don't fully understand? What will happen if we reduce the genetic diversity of our species? Doesn't embryo selection raise the specter of eugenics?

Think of the current debate over genetically modified crops, only magnified immensely. As the science progresses, some will undoubtedly call for strict restrictions; a few may resort to violence. But even if some societies severely restrict embryo selection, as Germany does today, those seeking it will only have to travel to other jurisdictions.

Given disparate cultural attitudes and the enormous promise of these technologies, it is all but certain that some countries will charge forward into the genetic frontier, not least because it will represent a lucrative industry with the potential to enhance national competitiveness. And, as with IVF decades ago, attitudes toward genetic selection and even manipulation will shift as these processes become more mainstream.

The essential problem we now face is that the science is advancing far faster than our collective imagination, which in turn is rapidly outdistancing our slow-to-evolve national and global regulatory frameworks. This fundamental mismatch may prevent the imposition of detrimental overregulation in the near term, but it also opens the door for potential future abuses and a harmful public backlash.

Following Britain's example by carrying out a more robust U.S. dialogue on mitochondrial transfer would be an important step forward. Congress could jump-start such a dialogue by establishing a task force to explore the societal implications of the genetics revolution, help organize the national conversation and chart a preliminary path forward.

This type of process would likely attract all forms of naysayers and could slow momentum in implementing lifesaving treatments. But given the individual and collective implications of these technologies, the danger of charging forward without public understanding and acceptance supersedes this risk.

If we do not now begin a wide-ranging and structured national dialogue on the rapidly unfolding genetics revolution and help to ramp up global consideration of these issues, fear and hysteria will eventually make such a conversation all but impossible and impede our progress in the future.