Researchers at the Los Alamos National Laboratory are using the ultimate supercomputer to analyze genetic sequences from more than 400 HIV-infected people to help find a vaccine against HIV/AIDS. The "Roadrunner" computer is being used to compare more than 100,000 sequences from both chronic and acute HIV patients in order to build a phylogenetic evolutionary family tree of the virus. Using the HIV samples provided by the international Center for HIV/AIDS Vaccine Immunology (CHAVI) consortium, the study is designed to identify common features of transmitted HIV, defining a target for a vaccine that would work before the body's immune response causes HIV to react and mutate, said Betty Korber, an HIV researcher at Los Alamos who is conducting the study with physicist Tanmoy Bhattacharya. As DNA sequencing is currently being revolutionized, computational advances will have to keep pace, said Korber. The Roadrunner will give researchers that kind of capacity, Bhattacharya said.