Conservation Genetics

, Volume 11, Issue 5, pp 2001–2013

Variety matters: adaptive genetic diversity and parasite load in two mouse opossums from the Brazilian Atlantic forest


  • Yvonne Meyer-Lucht
    • Leibniz Institute for Zoo and Wildlife ResearchEvolutionary Genetics
  • Celine Otten
    • Leibniz Institute for Zoo and Wildlife ResearchEvolutionary Genetics
  • Thomas Püttker
    • Leibniz Institute for Zoo and Wildlife ResearchEvolutionary Genetics
  • Renata Pardini
    • Departamento de Zoologia, Instituto de BiociênciasUniversidade de São Paulo
  • Jean Paul Metzger
    • Laboratório de Ecologia de Paisagem e Conservação (LEPaC), Departamento de Ecologia, Instituto de BiociênciasUniversidade de São Paulo
    • Leibniz Institute for Zoo and Wildlife ResearchEvolutionary Genetics
Research Article

DOI: 10.1007/s10592-010-0093-9

Cite this article as:
Meyer-Lucht, Y., Otten, C., Püttker, T. et al. Conserv Genet (2010) 11: 2001. doi:10.1007/s10592-010-0093-9


The adaptive potential of a species to a changing environment and in disease defence is primarily based on genetic variation. Immune genes, such as genes of the major histocompatibility complex (MHC), may thereby be of particular importance. In marsupials, however, there is very little knowledge about natural levels and functional importance of MHC polymorphism, despite their key role in the mammalian evolution. In a previous study, we discovered remarkable differences in the MHC class II diversity between two species of mouse opossums (Gracilinanus microtarsus, Marmosops incanus) from the Brazilian Atlantic forest, which is one of the most endangered hotspots for biodiversity conservation. Since the main forces in generating MHC diversity are assumed to be pathogens, we investigated in this study gastrointestinal parasite burden and functional associations between the individual MHC constitution and parasite load. We tested two contrasting scenarios, which might explain differences in MHC diversity between species. We predicted that a species with low MHC diversity would either be under relaxed selection pressure by low parasite diversity (‘Evolutionary equilibrium’ scenario), or there was a recent loss in MHC diversity leading to a lack of resistance alleles and increased parasite burden (‘Unbalanced situation’ scenario). In both species it became apparent that the MHC class II is functionally important in defence against gastrointestinal helminths, which was shown here for the first time in marsupials. On the population level, parasite diversity did not markedly differ between the two host species. However, we did observe considerable differences in the individual parasite load (parasite prevalence and infection intensity): while M. incanus revealed low MHC DAB diversity and high parasite load, G. microtarsus showed a tenfold higher population wide MHC DAB diversity and lower parasite burden. These results support the second scenario of an unbalanced situation.


Neotropical marsupialsMarmosops incanusGracilinanus microtarsusMata AtlânticaMajor histocompatibility complexPathogen-driven selection

Supplementary material

10592_2010_93_MOESM1_ESM.doc (42 kb)
Supplementary material 1 (DOC 42 kb)
10592_2010_93_MOESM2_ESM.doc (48 kb)
Supplementary material 2 (DOC 48 kb)

Copyright information

© Springer Science+Business Media B.V. 2010