The key to good health is to be physically active. The key to being active is to be born that way?
The well-documented importance of exercise in maintaining fitness has created the idea that individuals can manage their health by increasing their activity. But what if the inclination to engage in physical activity is itself significantly affected by factors that are predetermined? Two new studies suggest that the inclination to exercise may be strongly affected by genetics.
Controlled experiments into the effects of genetics on human activity have yet to be attempted, but recent studies on mice the standard test species for mammalian genetics have found genetic influences.
In a paper recently published in the journal Physiological Genomics, a team of researchers led by University of North Carolina at Charlotte kinesiologist J. Timothy Lightfoot announced that they had found six specific chromosomal locations that significantly correlate to the inheritance of a trait of high physical activity in mice, indicating that at least six genetic locations were affecting activity. Now, in a study forthcoming in The Journal of Heredity, the same team has identified 17 other genetic locations that also appear to control the level of physical activity in mice through interaction with each other, a genetic effect known as epistasis. Together, the located genes account for approximately 84% of the behavioral differences between mice that exhibit low activity levels and mice that show high activity traits.
"Can you be born a couch potato? In exercise physiology, we didn't used to think so, but now I would say most definitely you can," said Lightfoot.
The question of whether genetic influences can significantly affect activity in humans has never been rigorously studied, Lightfoot notes, but experiments with mice are indicating that the effect can be strong.
"The problem with the human literature in activity is th
|Contact: James Hathaway|
University of North Carolina at Charlotte