TERT

About TERT

TERT on chromosome 5p15.33 encodes the catalytic subunit of telomerase, the enzyme that adds repetitive DNA sequences to chromosome ends, called telomeres, compensating for the shortening that occurs each time a cell divides. Telomerase is active in stem cells and germ cells but largely silent in most adult tissues, so telomeres gradually shorten with age. Most cancers reactivate telomerase to achieve unlimited division, and mutations in the TERT promoter, which increase its expression, are among the most common non coding mutations in cancer, found frequently in melanoma, glioblastoma, bladder cancer, and thyroid cancer. Conversely, inherited loss of function variants in TERT and related genes cause telomere biology disorders, such as dyskeratosis congenita, pulmonary fibrosis, and bone marrow failure. Elizabeth Blackburn, Carol Greider, and Jack Szostak shared the 2009 Nobel Prize for discovering how telomeres and telomerase protect chromosomes.