Wild Thing: Less-domesticated mice harbor genetic secrets to long life

R. John Davenport

Key Words: longevity gene • life-span • mouse • QTL mapping • wild

Abstract: A life of leisure might seem attractive, but all that coddling could make one's genes go soft. Domesticated mice--selected for their ability to grow quickly, reproduce robustly, and mind their handlers--make experiments easy. Generations of captivity, however, might select against genes that could help them live longer, according to a new study.

In an effort to find mammalian genes that contribute to longevity, Klebanov and colleagues performed two breeding experiments. In each one, they carried out crosses with four strains of inbred mice to produce a genetically mixed population of grandchildren. One strain in each experiment originated from wild mice, while the others came from animals that had been domesticated prior to breeding. Then the researchers looked for genetic markers that tended to show up in long-lived offspring but not in individuals that died at a younger age. The resulting marker patterns led the team to two regions of the genome, one from each experiment, that were associated with longer living mice. The oldest 18% of animals that carried such tracts of DNA outlived the oldest 18% that did not by approximately 4 months. In both cases the markers that are linked to longevity come from strains derived from wild rather than domesticated mice.

No one can explain this result yet, but in general, animals that are larger and reproduce more tend not to live as long as their smaller and less fertile counterparts. Hence, the domestication process could select against genes that extend life-span. The researchers have yet to home in on the presumed longevity gene or genes that reside in the spans of DNA they identified. But the results hint that domesticated mice might lack the aging-related genes that geneticists are so wild about.

S. Klebanov, C. M. Astle, T. H. Roderick, K. Flurkey, J. R. Archer, J. Chen, D. E. Harrison, Maximum life spans in mice are extended by wild strain alleles. Exp. Biol. Med. 226, 854-859 (2001). [Abstract] [Full Text]

--Suggested by James M. Harper

Citation: R. J. Davenport, Wild Thing: Less-domesticated mice harbor genetic secrets to long life. Science's SAGE KE (10 October 2001), http://sageke.sciencemag.org/cgi/content/abstract/sageke;2001/2/nw7