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Frogs can now routinely be genetically engineered, providing fresh scope for
studying genes at work. Sylvia Evans and her colleagues from the medical
department at the University of California, San Diego, simplified the tricky
process of transferring genes into frog embryos with the help of parts of a
virus called inverted terminal repeats (Nature Biotechnology, vol 16, p
253). To check that the technique worked, Evans inserted a jellyfish gene for a
glowing green protein into the embryos and traced the protein in an adult frog鈥檚
tissue by its colour.