Abstract
The major histocompatibility complex (MHC) is a multiple-copy immune
gene family in vertebrates. Its genes are highly variable and code for
antigen-presenting molecules. Characterization of MHC genes in different
species and investigating the mechanisms that shape MHC diversity is an
important goal in understanding the evolution of biological diversity.
Here we developed a next generation sequencing (NGS) protocol to
genotype the MHC class I genes of 326 Godlewski’s buntings (Emberiza
godlewskii) sampled in the Western mountain area of Beijing from 2014 to
2016. A total of 184 functional alleles were identified, including both
non-classical and classical alleles. Classical alleles could be
clustered into nine supertypes. Compared with other passerine birds, the
individual diversity of MHC class I genes in Godlewski’s buntings is
intermediate. Ten amino acid sites in the antigen-binding domain showed
signatures of positive selection and eight of them exhibit high amino
acid polymorphism. These findings indicate the action of balancing
selection and provide a framework for subsequent investigation of
selection acting on MHC genes in Godlewski’s buntings.