On the Origin and Spread of an Adaptive Allele in Deer Mice
Catherine R. Linnen,1,*
Evan P. Kingsley,1
Jeffrey D. Jensen,2
Hopi E. Hoekstra1
Adaptation is a central focus of biology, although it can be
difficult to identify both the strength and agent of selection
and the underlying molecular mechanisms causing change. We studied
cryptically colored deer mice living on the Nebraska Sand Hills
and show that their light coloration stems from a novel banding
pattern on individual hairs produced by an increase in
Agouti expression caused by a
cis-acting mutation (or mutations), which
either is or is closely linked to a single amino acid deletion
in
Agouti that appears to be under selection. Furthermore, our
data suggest that this derived
Agouti allele arose de novo after
the formation of the Sand Hills. These findings reveal one means
by which genetic, developmental, and evolutionary mechanisms
can drive rapid adaptation under ecological pressure.
2 Center for Theoretical Evolutionary Genomics, Department of Integrative Biology, University of California, Berkeley, 3060 Valley Life Sciences Building, Berkeley, CA 94720, USA.
* To whom correspondence should be addressed. E-mail: clinnen{at}oeb.harvard.edu
