Current address: Center for Investigation of Biodiversity and Genetic Resources (CIBIO), University of Porto, Vairao 4485-661, Portugal
HETEROZYGOSITY-FITNESS CORRELATIONS REVEALED BY NEUTRAL AND CANDIDATE GENE MARKERS IN ROE DEER FROM A LONG-TERM STUDY
Article first published online: 10 OCT 2008
© 2008 The Author(s). Journal compilation © 2009 The Society for the Study of Evolution
Volume 63, Issue 2, pages 403–417, February 2009
How to Cite
Da Silva, A., Gaillard, J.-M., Yoccoz, N. G., Hewison, A. J. M., Galan, M., Coulson, T., Allainé, D., Vial, L., Delorme, D., Van Laere, G., Klein, F. and Luikart, G. (2009), HETEROZYGOSITY-FITNESS CORRELATIONS REVEALED BY NEUTRAL AND CANDIDATE GENE MARKERS IN ROE DEER FROM A LONG-TERM STUDY. Evolution, 63: 403–417. doi: 10.1111/j.1558-5646.2008.00542.x
A. Da Silva and J. M. Gaillard contributed equally to this article.
- Issue published online: 29 JAN 2009
- Article first published online: 10 OCT 2008
- Received March 29, 2008Accepted August 19, 2008
- Candidate genes;
- functional genes;
- juvenile survival;
Heterozygosity-fitness correlations (HFCs) are increasingly reported but the underlying mechanisms causing HFCs are generally poorly understood. Here, we test for HFCs in roe deer (Capreolus capreolus) using 22 neutral microsatellites widely distributed in the genome and four microsatellites in genes that are potentially under selection. Juvenile survival was used as a proxy for individual fitness in a population that has been intensively studied for 30 years in northeastern France. For 222 juveniles, we computed two measures of genetic diversity: individual heterozygosity (H), and mean d2 (relatedness of parental genomes). We found a relationship between genetic diversity and fitness both for the 22 neutral markers and two candidate genes: IGF1 (Insulin-like Growth Factor I) and NRAMP (natural resistance-associated macrophage protein). Statistical evidence and the size of genetic effects on juvenile survival were comparable to those reported for early development and cohort variation, suggesting a substantial influence of genetic components on fitness in this roe deer population. For the 22 neutral microsatellites, a correlation with fitness was revealed for mean d2, but not for H, suggesting a possible outbreeding advantage. This heterosis effect could have been favored by introduction of genetically distant (Hungarian) roe deer to the population in recent times and, possibly, by the structuring of the population into distinct clans. The locus-specific correlations with fitness may be driven by growth rate advantages and resistance to diseases known to exist in the studied population. Our analyses of neutral and candidate gene markers both suggest that the observed HFCs are likely mainly due to linkage with dominant or overdominant loci that affect fitness ("local" effect) rather than to a genome-wide relationship with homozygosity due to inbreeding ("general" effect).