Illustration of the Australian-US biochemist Elizabeth Blackburn (born 1948). Blackburn co-discovered the enzyme telomerase in 1984. She identified that telomeres (ends of chromosomes) were formed from short repeating sections of DNA (deoxyribonucleic acid) and that telomerase had a role in preventing their shortening during DNA replication. For this work she shared the 2009 Nobel Prize in Physiology or Medicine with Carol Greider (her co-discoverer) and Jack W. Szostak.