Rapid loss of MHC class II variation in a bottlenecked population is explained by drift and loss of copy number variation.
J Evol Biol
; 24(9): 1847-56, 2011 Sep.
Article
em En
| MEDLINE
| ID: mdl-21605219
ABSTRACT
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.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Genes MHC da Classe II
/
Deriva Genética
/
Galliformes
/
Variações do Número de Cópias de DNA
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
J Evol Biol
Assunto da revista:
BIOLOGIA
Ano de publicação:
2011
Tipo de documento:
Article
País de afiliação:
Estados Unidos