Fluorescent transgenic mice. Green glowing baby mice that have a jellyfish gene that codes for GFP (green fluorescent protein), seen with a normal mouse. These genetically engineered transgenic mice may aid the study of cancer. They are the result of research by Professor M. Okabe at Osaka University, Japan. Okabe and his team obtained the GFP gene from the jellyfish Aequorea victoria. A virus was used to introduce the gene into fertilised mice eggs. Such mice have skin that fluoresces green under blue light. GFP may be used to mark cancer cells or drugs in order to study cancer as it travels around the body.