Gene drives are an acceleration of mutation and evolution. Alter the genes in a few specimens that give them a specific trait, and let them reproduce the next generation with that trait. Do it right, and wipe out certain diseases like malaria. Do it wrong, and create a pandemic. CRISPR, a new gene-editing tool, enables such a process. The potential is great. The threat is great. Just like other bio-hazards and bio-weapons, it will be developed with good intentions and hopefully under strict controls. The appeal and the concern is that gene drives may be easier and cheaper to implement than many other bio-technologies.
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