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