Homozygosity at a class II MHC locus depresses female reproductive ability in European brown hares.
The link between adaptive genetic variation, individual fitness and wildlife population dynamics is fundamental to the study of ecology and evolutionary biology. In this study, a Bayesian modelling approach was employed to examine whether individual variability at two major histocompatibility complex (MHC) class II loci (DQA and DRB) and eight neutral microsatellite loci explained variation in female reproductive success for wild populations of European brown hare (Lepus europaeus). We examined two aspects of reproduction: the ability to reproduce (sterility) and the number of offspring produced (fecundity). Samples were collected from eastern Austria, experiencing a sub-continental climatic regime, and from Belgium with a more Atlantic-influenced climate. As expected, reproductive success (both sterility and fecundity) was significantly influenced by age regardless of sampling locality. For Belgium, there was also a significant effect of DQA heterozygosity in determining whether females were able to reproduce (95% highest posterior density interval of the regression parameter [-3.64, -0.52]), but no corresponding effect was found for Austria. In neither region was reproduction significantly associated with heterozygosity at the DRB locus. DQA heterozygotes from both regions also showed a clear tendency, but not significantly so, to produce a larger number of offspring. Predictive simulations showed that, in Belgium, sub-populations of homozygotes will have higher rates of sterile individuals and lower average offspring numbers than heterozygotes. No similar effect is predicted for Austria. The mechanism for the spatial MHC effect is likely to be connected to mate choice for increased heterozygosity or to the linkage of certain MHC alleles with lethal recessives at other loci.
Smith
Steve
S
Research Institute of Wildlife Ecology, University of Veterinary Medicine Vienna, Savoyenstr. 1, 1160 Vienna, AustriaDepartment of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UKDepartment of Biology, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, BelgiumKonrad Lorenz Institute for Ethology, Savoyenstr. 1A, 1160 Vienna, AustriaInstitute of Wildlife Biology and Game Management, University of Natural Resources and Applied Life Sciences, Gregor-Mendel-Str. 33, 1180 Vienna, Austria.
Mang
Thomas
T
De Bellocq
Joelle Goüy
JG
Schaschl
Helmut
H
Zeitlhofer
Claudia
C
Hackländer
Klaus
K
Suchentrunk
Franz
F
D000483:Alleles; D000818:Animals; D001317:Austria; D001499:Bayes Theorem; D001530:Belgium; D005260:Female; D005298:Fertility / Q000235:genetics; D005787:Gene Frequency; D056426:Genetic Loci; D034621:Hares / Q000235:genetics*; D000949:Histocompatibility Antigens Class II / Q000235:genetics*; D006720:Homozygote; D007247:Infertility, Female / Q000235:genetics; D018895:Microsatellite Repeats; D008957:Models, Genetic; D015233:Models, Statistical; D012098:Reproduction / Q000235:genetics*
D000949:Histocompatibility Antigens Class II