Manolis Kellis, 29
Manolis Kellis develops algorithms and techniques for analyzing the entire genomes of different species, the better to understand those genomes. Kellis began his PhD work with little knowledge of biology: his undergraduate degree is in computer science. For his thesis, he compared the genomes of four yeast species to identify all the genes and regulatory sequences in one of them--a project hes glad no one told him was believed to be impossible.
Comparing the genomes of multiple closely related species has proved to be a powerful new tool for finding genes and the sequences that regulate them, and for learning about how genomes evolve (see "Finding Evolution's Signatures").
After validating his methods in yeast, Kellis has moved to the human genome, which he has so far compared with those of the mouse, rat, and dog. His work is providing an intimate understanding of the human genome that may give drug developers new points of entry in their attempts to combat viruses and other causes of disease.
Kellis discusses his work as a computational biologist in this video clip.