Elizabeth Blackburn

This enzyme, called telomerase, slows the rate at which telomeres degrade, and research indicates that healthy people with longer telomeres have less risk of developing the common illnesses of aging - like heart disease, diabetes, and cancer, which are three big killers today.

I spent my first 4 years living in the tiny town of Snug, by the sea near Hobart. Curious about animals, I would pick up ants in our backyard and jellyfish on the beach.

At Cambridge, there was a completely unintimidating culture, and there were no class divisions among the students.

In humans, the thing is that as we mature, our telomeres slowly wear down. So the question has always been: 'Did that matter?' Well, more and more, it seems like it matters.

Generally, we try to have a situation where the person is healthy, so you're not confounded by disease. So, that means that healthy individuals are donating their blood samples for the studies.

Observational studies show that exercise, nutritional supplements and reducing psychological stress can help. Chronic high stress and smoking can lead to accelerated telomere shortening.

I'm pretty good about getting some exercise every day - well, most days. The secret for me was to put the elliptical in front of the TV.

Challenges in medicine are moving from 'Treat the symptoms after the house is on fire' to 'Can we preserve the house intact?'

Medicine has been successful by treating diseases in a very specific way once the damage is done. But telomere length integrates a lot of factors together and gives you an overall picture of risk for what is now emerging as a lot of diseases that tend to occur together, such as diabetes and heart disease.

In my lab, we're finding that psychological stress actually ages cells, which can be seen when you measure the wearing down of the tips of the chromosomes, those telomeres.

I was born in the small city of Hobart in Tasmania, Australia, in 1948. My parents were family physicians. My grandfather and great grandfather on my mother's side were geologists.

No one ever said, 'Be a doctor.' But because so many members of my extended family - aunts, uncles - were doctors, there was this expectation that I'd probably be a physician.