Adaptive tolerance to a pathogenic fungus drives major histocompatibility complex evolution in natural amphibian populations.

ABSTRACT: Amphibians have been affected globally by the disease chytridiomycosis, caused by the fungus Batrachochytrium dendrobatidis (Bd), and we are just now beginning to understand how immunogenetic variability contributes to disease susceptibility. Lineages of an expressed major histocompatibility complex (MHC) class II locus involved in acquired immunity are associated with chytridiomycosis susceptibility in controlled laboratory challenge assays. Here, we extend these findings to natural populations that vary both in exposure and response to Bd We find that MHC alleles and supertypes associated with Bd survival in the field show a molecular signal of positive selection, while those associated with susceptibility do not, supporting the hypothesis that heritable Bd tolerance is rapidly evolving.

SUBMITTER: Savage AE 

PROVIDER: S-EPMC4822461 | biostudies-literature | 2016 Mar

REPOSITORIES: biostudies-literature