Genetic slippage after sex maintains diversity for parasite resistance in a natural host population.
Sci Adv
; 8(46): eabn0051, 2022 11 16.
Article
em En
| MEDLINE
| ID: mdl-36399570
ABSTRACT
Although parasite-mediated selection is a major driver of host evolution, its influence on genetic variation for parasite resistance is not yet well understood. We monitored resistance in a large population of the planktonic crustacean Daphnia magna over 8 years, as it underwent yearly epidemics of the bacterial pathogen Pasteuria ramosa. We observed cyclic dynamics of resistance Resistance increased throughout the epidemics, but susceptibility was restored each spring when hosts hatched from sexual resting stages. Host resting stages collected across the year showed that largely resistant host populations can produce susceptible sexual offspring. A genetic model of resistance developed for this host-parasite system, based on multiple loci and strong epistasis, is in partial agreement with our findings. Our results reveal that, despite strong selection for resistance in a natural host population, genetic slippage after sexual reproduction can be a strong factor for the maintenance of genetic diversity of host resistance.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Parasitos
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Sci Adv
Ano de publicação:
2022
Tipo de documento:
Article