The key gene for skin pigmentation in toads (and in humans, by the way, too) codes for the enzyme tyrosinase, which controls the production of melanin. Cooper reasoned that if this gene was turned off, the result would be light-colored toads, not dark ones. She mixed several eggs and sperm in a petri dish, injected CRISPR-related substances into the resulting embryos, and waited. Three unusually colorful tadpoles appeared. One of them died. The other two, both males, have grown into spotted toads. They were christened Spot and Blondie. “I was absolutely thrilled when it happened,” Tizard told me. Then Cooper began to "turn off" the toxicity of toads.
The poison (bufotoxin) in the toad-aga is produced in large parotid glands whatsapp mobile number list located closer to the back, as well as in smaller glands scattered throughout the body. Isolated in its normal state, it simply makes mammals sick. If the toad feels danger, it produces a special enzyme - bufotoxin hydrolase - a hundredfold. Using CRISPR technology, Cooper edited the second batch of embryos and removed part of the gene encoding bufotoxin hydrolase. The result was a batch of non-venomous toads. After the conversation, Cooper offered to look at the toads themselves.
To do this, we traveled deeper into the AAHL, passing through several sealed doors and security levels. We all put on protective suits over our clothes and shoe covers over our shoes. Cooper sprayed my recorder with some kind of disinfectant. The sign on the door read: “Quarantine zone. Violators face fines." I decided it was best not to tell The Odin about my own, far less safe, gene-editing adventures. Behind the doors was something like a sterile menagerie, filled with animals in enclosures of various sizes. It smelled of hospital and petting zoo at the same time. Poison-free toads hopped around a few cages around a plastic tank. There were about a dozen of them, about ten weeks old.