The groundwork for these advances has been laid over recent years by genetic mapping--the arrangement of mutable sites on a chromosome as deduced from genetic recombination experiments. This mapping has revealed remarkable similarities, or conservation, in the genes of a few organisms up and down the evolutionary tree. By altering genes from conserved areas of the genome in such organisms as yeast, nematode worms, fruit flies, zebra fish, mice, and cats, developmental biologists are elucidating the biochemical pathways and are finding new points of intervention for drugs to treat humans.
Photo: Exelixis FLY MODEL: Researchers at Exelixis Pharmaceuticals insert a human disease gene in the eye of a fruit fly to investigate the signaling pathway as a normal eye (left), degenerates into a "rough" eye. "Mass genetic mapping has put a library of just about all the known genes into the public domain," notes Geoffrey Duyk, chief scientific officer of ...