Joint last authors.
Rapid loss of MHC class II variation in a bottlenecked population is explained by drift and loss of copy number variation
Article first published online: 23 MAY 2011
© 2011 The Authors. Journal of Evolutionary Biology © 2011 European Society For Evolutionary Biology
Journal of Evolutionary Biology
Volume 24, Issue 9, pages 1847–1856, September 2011
How to Cite
EIMES, J. A., BOLLMER, J. L., WHITTINGHAM, L. A., JOHNSON, J. A., VAN OOSTERHOUT, C. and DUNN, P. O. (2011), Rapid loss of MHC class II variation in a bottlenecked population is explained by drift and loss of copy number variation. Journal of Evolutionary Biology, 24: 1847–1856. doi: 10.1111/j.1420-9101.2011.02311.x
- Issue published online: 12 AUG 2011
- Article first published online: 23 MAY 2011
- Received 23 February 2011; revised 10 April 2011; accepted 28 April 2011
- copy number variation;
- genetic drift;
- major histocompatibility complex;
- Tympanuchus cupido
Population bottlenecks may reduce genetic variation and potentially increase the risk of extinction. Here, we present the first study to use historic samples to analyse loss of variation at the major histocompatibility complex (MHC), which plays a central role in vertebrate disease resistance. Balancing selection acts on the MHC and could moderate the loss of variation expected from drift; however, in a Wisconsin population of greater prairie-chickens (Tympanuchus cupido), the number of MHC class II B alleles per individual declined by 44% following a population bottleneck, compared to a loss of only 8% at microsatellites. Simulations indicate that drift likely reduced MHC variation at the population level, as well as within individuals by reducing the number of gene copies per individual or by fixing the same alleles across multiple loci. These multiple effects of genetic drift on MHC variation could have important implications for immunity and fitness.