Balancing selection versus allele and supertype turnover in MHC class II genes in guppies.

ABSTRACT: Selection pressure from parasites is thought to be a major force shaping the extreme polymorphism of the major histocompatibility complex (MHC) genes, but the modes and consequences of selection remain unclear. Here, we analyse MHC class II and microsatellite diversity in 16 guppy (Poecilia reticulata) populations from two islands (Trinidad and Tobago) that have been separated for at least 10 ky. Within-population MHC diversity was high, but allele sharing was limited within islands and even lower between islands, suggesting relatively fast turnover of alleles. Allelic lineages strongly supported in phylogenetic analyses tended to be island-specific, suggesting rapid lineage sorting, and an expansion of an allelic lineage private to Tobago was observed. New alleles appear to be generated l

SUBMITTER: Herdegen-Radwan M 

PROVIDER: S-EPMC8027376 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature