Molecular characterization of MHC class I genes in Four species of Turdidae family to assess genetic diversity and selection.

In vertebrate animals, the molecules encoded by major histocompatibility complex (MHC) genes play an essential role in the adaptive immunity. MHC class I deal with intracellular pathogens (Virus) in birds. MHC class I diversity depends on the consequence of local and global environment selective pressure and gene flow. Here, we evaluated the MHC class I gene in four species of Turdidae family from a broad geographical area of northeast China. We isolated 77 MHC class I sequence, including 47 putatively functional sequences and 30 pseudo sequences from 80 individuals. Method based on analysis of cloned amplicons (n=25) for each species, we found two and seven MHC I sequence per individual indicates more than one MHC I loci identified in all sampled species. Results revealed an overall elevated genetic diversity at MHC class I, evidence of different selection patterns among the domains of PBR and non-PBR. Alleles found to be divergent with overall polymorphic sites per species ranging between 58 to 70 (out of 291 sites). Moreover, trans-species alleles were evident due to convergent evolution or recent speciation for the genus. Phylogenetic relationships among MHC I show an intermingling of alleles clustering among Turdidae family rather than between other passerines. Pronounced MHC I gene diversity is essential for existence of species. Our study signifies a valuable tool for the characterization of evolutionary relevant difference across a population of birds with high conservational concerns.