科学美国人60秒:Nobelist Talks about Exercise and Chromosome Integrity

Telomeres are parts of chromosomes that protect the ends of the chromosomes. They’re often likened to the aglets at the ends of shoelaces. And like aglets eventually crack, telomeres tend to get shorter over time, with each division of the cell. But they can be topped off again by an enzyme called telomerase reverse transcriptase. Various age-related diseases are associated with shortened telomeres.

Elizabeth Blackburn won a Nobel Prize for her discoveries about telomeres and the telomerase enzyme. She recently did a Google Hangout with Scientific American editor-in-chief Mariette DiChristina, which included taking questions from attendees via social media:

MD: “Can telomeres actually grow longer in response to exercise?”

EB: “Well, we don’t know if telomeres actually grow with exercise. But what is known, I’ll give you a great example of a study. We didn’t do it. Twins. So they looked at twins. This is a big study. And they said, of the twins who’ve actually done exercise, the one who did exercise and the one who didn’t, so you’d be able to find a lot of twins it turns out, in that situation. And they said, who’s got the longer telomeres. And it was the twin who did some exercise. The one who didn’t had shorter telomeres. And yet their genes are the same. So you see, that tells you something quite nice.

“And of course, well, you say, was it really the exercise, or was it something else that was different between the twins. And that’s where epidemiology studies have to be done so carefully. But over and over again, we keep finding that same result—that the exercise is associated with a person who will have less telomere shortening. And so it looks like now it really is the exercise that’s somehow keeping the shortening process from being too fast.”

The entire 27-minute Google Hangout with Mariette DiChristina and Nobel Laureate Elizabeth Blackburn is on our Web site. Just google Hangout and Elizabeth Blackburn.

—Steve Mirsky