It was an accidental mutation of the Tetrahymena thermophila, a pond organism, during a lab experiment that revealed that the enzyme telomerase keeps the protective caps on the end of chromosomes long. Speaking at the 61st Meeting of Nobel Laureates at Lindau, Elisabeth Blackburn compared the caps, called telomeres, to the tips on the end of a shoelace that prevent it from fraying. Telomeres protect DNA during cell division.
Most Tetrahymena are immortal, Blackburn explained, and they have lots of telemorase, but the mutant had shorter and shorter telomeres over time, so its cells started to die. It was found that the mutant had no telemorase in its cells.
The mystery of the function of telomeres had been solved. Labs from around the world began to work on the implications of telomeres for human health.
Blackburn speaking at the Lindau meeting, photo: Christine Ottery
"Many of the diseases of ageing, including cancers, are associated with the shortening of telomeres," Blackburn said. Others include: pulmonary fibrosis, cardiovascular disease, osteoarthritis, osteoporosis, diabetes. Even the risk factors for these diseases increases with short telomeres.
With a global aging population, the importance of tackling these chronic diseases is increasing. Diabetes is a worldwide problem, for instance, affecting 10 per cent of people in the developing and developed world.
Luckily, stopping our own telomeres from shortening – or possibly even restoring them – is potentially something within our grasp. Chronic life stress and multiple trauma exposures are implicated in telomere shortness, Blackburn said, as are pessimism and hostility. But education, excercise and stress reduction are factors in preventing telomere shortening, thereby reducing the risk of disease.
Blackburn encouraged the audience to get involved in telomere research. She said that there is so much data on telemores, including 675,000 genetic snips, that there is a lot of work yet to be done to determine how chronic diseases can be prevented.
You can watch the video of Blackburn’s fascinating talk below: