Glowing Zebrafish – Possible Tools for Regulation in China, and Pets
Technology keeps evolving, and so now China may see use of zebrafish as tools for regulatory action. Specifically, after some genetic splicing, zebra fish are in use as living, glowing biomarkers to indicate quickly the presence of particular toxins. Some will develop tumors in the presence of certain substances. Zebrafish are often used for experiments because they are relatively simple and transparent, which helps with observing results of experiments.
Apparent variants are sold as GloFish for pets.
See this page at Wikipedia for the backstory on the technology.