Michael Morris Rosbash (born March 7, 1944) is an American geneticist and chronobiologist of Jewish descent. Rosbash is a professor at Brandeis University and investigator at the Howard Hughes Medical Institute. Rosbash's research group cloned the "Drosophila" period gene in 1984 and proposed the Transcription Translation Negative Feedback Loop for circadian clocks in 1990. 