Cooper next turned her attention to “breaking” the toads’ toxicity. Cane toads store their poison in glands behind their shoulders. In its raw form, this poison is merely sickening. But toads can, when attacked, produce an enzyme—bufotoxin hydrolase—that amplifies the poison’s potency a hundredfold. Using CRISPR, Cooper edited a second batch of embryos to delete a section of the gene that codes for bufotoxin hydrolase. The result was a batch of detoxified toadlets.
