Contrasting epidemic histories reveal pathogen-mediated balancing selection on class II MHC diversity in a wild songbird.

ABSTRACT: The extent to which pathogens maintain the extraordinary polymorphism at vertebrate Major Histocompatibility Complex (MHC) genes via balancing selection has intrigued evolutionary biologists for over half a century, but direct tests remain challenging. Here we examine whether a well-characterized epidemic of Mycoplasmal conjunctivitis resulted in balancing selection on class II MHC in a wild songbird host, the house finch (Carpodacus mexicanus). First, we confirmed the potential for pathogen-mediated balancing selection by experimentally demonstrating that house finches with intermediate to high multi-locus MHC diversity are more resistant to challenge with Mycoplasma gallisepticum. Second, we documented sequence and diversity-based signatures of pathogen-mediated balancing selection at cl

SUBMITTER: Hawley DM 

PROVIDER: S-EPMC3264569 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature