The Risks of Assisting Evolution

THERE are four locked doors guarding a specialized lab at the Harvard School of Public Health. The doors are meant to prevent insects inside the lab from venturing out — which is essential, because researchers behind those doors are re-engineering mosquitoes by cutting and pasting bits of DNA with tools unimaginable a decade ago.

If researchers can figure out the right combination of genes, they’ll manufacture a mosquito resistant to malaria, which could save hundreds of thousands of lives every year. But geneticists, bioethicists and others who understand the implications of this new technology are apprehensive. To an astonishing degree, these new tools, which include a technique called Crispr-Cas9, allow us to bend evolution to our will. But will we harness these new technologies to help our planet? Or spark an ecological catastrophe?

In university labs, corporate R&D centers and even inside amateur D.I.Y. laboratories, researchers are creating genetically modified organisms at an unprecedented pace. This biotechnological revolution is so fast-moving that it hasn’t yet fully filtered into the public’s awareness or policy...