Genome analysis - Vulture

Review: The first whole genome and transcriptome of the cinereous vulture reveals adaptation in the gastric and immune defense systems and possible convergent evolution between the Old and New World vultures

Abstract

Backgrounds: The cinereous vulture is the largest bird of prey and plays a key role in the ecosystem by removing carcasses, thus preventing the spread of diseases. its feeding habits force it to cope with constant exposure to pathogens, making this species an interesting target for discovering functionally selected genetic variants. Furthermore, the presence of two independently evolved vulture groups, Old World and New World vultures, provides a natural experiment in which to investigate convergent evolution due to obligate scavenging.

Results: We sequenced the genome of a cinereous vulture, and mapped it to the bald eagle reference genome, a close relative with a divergence time of 18 million years. By comparing the cinereous vulture to other avian genomes, we find positively selected genetic variations in this species associated with respiration, likely linked to their ability of immune defense responses and gastric acid secretion, consistent with their ability to digest carcasses. Comparisons between the Old World and New World vulture groups suggest convergent gene evolution. We assemble the cinereous vulture blood transcriptome from a second individual, and annotate genes. Finally, we infer the demographic history of the cinereous vulture which shows marked fluctuations in effective population size during the late Pleistocene.

Conclusions: We present the first genome and transcriptome analyses of the cinereous vulture compared to other avian genomes and transcriptomes, revealing genetic signatures of dietary and environmental adaptations accompanied by possible convergent evolution between the Old World and New World vultures.

 

Discussion

In this article, the most important point is that there are no obvious motivations or hypothesis. They just mentioned that they sequenced this whole cinereous vulture transcriptome for the first time, no other meanings. It is just like screening methods. Although the first whole transcriptome sequencing can impacts a lot in biological meaning, it would be better if they suggested further approaches.

There are no specific details in their methods such as RNA and cDNA extraction. And overall contents are proceeding with just machine or software names which has no other meanings.