Arthur L. Horwich, M.D., Eugene Higgins Professor of Genetics and professor of pediatrics, has been elected a Fellow of the American Association for the Advancement of Science (AAAS). The AAAS named 449 members Fellows this year, for “advancing science applications that are deemed scientifically or socially distinguished.” Horwich studies a large ring-shaped molecular machine called a chaperonin that mediates protein folding within a large cavity.