Comparative and evolutionary insights into CD4 gene across mammalian and avian taxa.

Abstract

The present day genetic architecture of a species bears much significance to its closely related species which is due to species-specific differences, shaped by different evolutionary forces across time scale. With the availability of whole genome sequence of several closely related species, it is now possible to infer evolutionary patterns of genes and genomes in specific lineages. To this respect, CD4 gene, primarily responsible for defensive mechanism in human, is conserved across a few taxa, and thus, comparative genomic studies could be useful for better understanding of host-pathogen biology. Comparative and evolutionary analyses were performed in eleven taxa (10 mammalian and avian) with different statistical algorithms. Phylogenetic inferences revealed recent divergence of human and chimpanzee, and pig was found to be diverged from rest of the taxa significantly. Additionally, gene length, microsatellites, and secondary structures were observed across taxa. The genetic architecture of CD4 gene and its evolutionary history in different mammalian taxa provide crucial evidence in support of the fact that this gene might have been evolving at a similar rate to other human immune system genes. Future population-based study and structural modeling would unravel the differential ability to interact with HIV virus and influence immune system in humans.