This structure is called a telomere, and it helps protect the DNA from damage and our bodies from cancer. But there’s a catch: every time our cells divide to help us grow and stay healthy, the telomere gets a tiny bit shorter. Our telomeres get shorter and shorter until they are so short that the cells can no longer replicate themselves. This signals to our cells that it is time for them to retire. Put simply, telomere shortening is part of the natural process of aging that happens to all living things.
However, this process can happen faster for some. One of the questions I am trying to answer as I investigate seabirds in Norway is: Do the birds’ diets affect their health? One way to measure their health is by looking at the length of their telomeres. When birds are stressed – like when they can’t find enough healthy food – the caps that protect their DNA actually shorten faster than the telomeres of birds that live in less stressful conditions. Studies from other researchers have shown that we can predict a bird’s chance of survival based on the length of its telomeres! As it turns out, longer telomeres might mean longer survival.
This is exactly what we’re measuring in the lab. Amazing modern technology called qPCR allows scientists like me to extract a tiny amount of DNA from blood samples we collected from the birds, copy it millions of times, and measure the length of the telomeres. We use a computer that gives us a telomere signal; if it’s strong, the telomeres are longer, and if it’s weak, we know they’re shorter. The telomere length of each bird tells us all about its aging process, stress levels and even probability of survival! Pretty cool, right?
