Thomas Robert Cech (born December 8, 1947) is an American chemist who shared the 1989 Nobel Prize in Chemistry with Sidney Altman, for their discovery of the catalytic properties of RNA. Cech discovered that RNA could itself cut strands of RNA, which showed that life could have started as RNA. He also studied telomeres, and his lab discovered an enzyme, TERT (telomerase reverse transcriptase), which is part of the process of restoring telomeres after they are shortened during cell division. As president of Howard Hughes Medical Institute, he promoted science education, and he teaches an undergraduate chemistry course at the University of Colorado.