Telomeres are to chromosomes what plastic caps are to the ends of shoelaces – they stop them unravelling as they age. Without telomeres, chromosomes would gradually lose their genetic information as cells replicate. For this reason – backed by some research – scientists believe longer telomeres are better for health. But now a new genomic study suggests longer telomeres may also increase the risk of developing deadly brain cancers known as gliomas.
Led by the University of California San Francisco (UCSF), the study focuses on two common variants of telomere-related genes known as TERT and TERC that lead to longer telomeres. TERT is carried by 51% of people and TERC is carried by 72%.
However, it is rather unusual for common variants to increase risk of disease, so the researchers suggest perhaps a genetic balancing act is going on between benefit and risk. On the benefit side, carrying longer telomere variants generally promotes overall health, while on the risk side, carrying them can also raise risk of high-grade gliomas, but for most carriers, the benefit trumps the risk, as gliomas, although nearly always fatal, are relatively rare.
Read the full, original story: Genes behind longer telomeres linked to raised risk of brain cancer