If you take a look at your grandparents faces, you’re likely to see a few smile lines etched into their skin and a grey hair or two (or many more, if they’re unlucky!). The process of ageing in all lifeforms, from humans to frogs to bacteria, is due to the shortening of telomeres.
Humans are made up of billions of cells that originated through the dividing and duplicating process that you might have already studied in science class.
“But there is a glitch in the way DNA is copied. It’s just one of those facts of life,” says Elizabeth. “Every time the cell divides and the DNA is copied, some of that DNA from the ends gets worn down and shortened.
“Telomeres act like the protective caps at the ends of your shoelace to keep the shoelace, or your chromosomes, from fraying. When that tip gets too short, it falls off and that worn down telomere sends a signal to the cells [to stop them from duplicating].”
In their lab in the 1980s, Elizabeth and her graduate student Carol Greider noticed that a small single-celled protozoan called ‘Tetrahymena’ or ‘pond scum’ never experienced this cell ageing that other organisms inevitably suffer.
Looking at it more closely, Elizabeth and Carol discovered that Tetrahymena had an abundance of an enzyme that could replenish the Tetrahymena’s telomeres. This enzyme had never before been discovered, and so Elizabeth and Carol named the newfound enzyme ‘telomerase’.
It may seem like this enzyme is the key to anti-aging and immortality, but Elizabeth warns that there is a key drawback to the abundance of telomerase in humans. Increasing the amount of this enzyme in your body may help to reduce risks of diseases like diabetes or heart disease for example, but it greatly increases your risk of developing several types of cancer. This is because telomerase facilitates faster and easier reproduction of the unwanted cancer cells, just like it would for any other cell in the body.
Elizabeth, Carol and geneticist Jack W. Szostak were awarded the Nobel Prize in Physiology or Medicine in 2009 for the groundbreaking discovery. With this achievement under her belt, Elizabeth Blackburn is the first ever Tasmanian Nobel laureate, born in Hobart in 1948.
Elizabeth Blackburn’s pathway to the Nobel prize:
> > Bachelor of Science, University of Melbourne
> > Master of Science, University of Melbourne
> > PhD in genetic research, University of Cambridge
> > Postdoctoral researcher, Yale University
> > Nobel laureate in Physiology or Medicine, 2009
Profile image by US Embassy Sweden [CC BY 2.0 (https://creativecommons.org/licenses/by/2.0)], via Wikimedia Commons
“There is a glitch in the way DNA is copied. It’s just one of those facts of life.”
Author: Eliza Brockwell
Eliza is passionate about creating content that encourages diversity of representation in STEM.