Keeping genetic engineering localized
Genetic engineering tools that spread genes within a target species have the potential to humanely control harmful pests as well as eradicate parasitic diseases such as malaria. The tools, known as gene drives, ensure that engineered organisms transmit desired genetic variants to their offspring. These variants could ensure, for example, that the organisms only produce male offspring, or sterile females. In this way, gene drives could be used to exterminate insects such as mosquitoes that carry pathogens, and that can spread malaria, dengue, and the Zika virus. Gene drives could also be used to control invasive species such as rodents that can threaten the survival of native animals. However, previously described versions of gene drives based on the CRISPR genome editing system have the potential to spread far wider than their intended local population — to affect an entire species. The affects could also spread across international boundaries, potentially leading to disputes between countries where...