Balancing selection at a frog antimicrobial peptide locus: fluctuating immune effector alleles?

ABSTRACT: Balancing selection is common on many defense genes, but it has rarely been reported for immune effector proteins such as antimicrobial peptides (AMPs). We describe genetic diversity at a brevinin-1 AMP locus in three species of leopard frogs (Rana pipiens, Rana blairi, and Rana palustris). Several highly divergent allelic lineages are segregating at this locus. That this unusual pattern results from balancing selection is demonstrated by multiple lines of evidence, including a ratio of nonsynonymous/synonymous polymorphism significantly higher than 1, the ZnS test, incongruence between the number of segregating sites and haplotype diversity, and significant Tajima's D values. Our data are more consistent with a model of fluctuating selection in which alleles change frequencies over time t

SUBMITTER: Tennessen JA 

PROVIDER: S-EPMC2582982 | biostudies-literature | 2008 Dec

REPOSITORIES: biostudies-literature