Capuchin monkey genome reveals clues to its long life and large brain

An international team of scientists sequenced the genome of a capuchin monkey for the first time, uncovering new genetic clues to the evolution of their long lifespan and large brain.

Posted in PNAS, the work was led by the University of Calgary in Canada and involved researchers from the University of Liverpool.

“Capuchins have the largest relative brain size of all monkeys and can live beyond 50 years despite their small size, but their genetic basis has remained unexplored until now,” explains Professor Joao Pedro De Magalhaes , who is studying aging at the University of Liverpool.

Researchers developed and annotated a reference assemblage for white-faced capuchin monkeys (Cebus mimic) to explore the evolution of these traits.

Using a comparative genomics approach covering a wide diversity of mammals, they identified genes under evolutionary selection associated with longevity and brain development.

“We have found positive selection signatures on the genes underlying both traits, which helps us better understand how these traits evolve.” Additionally, we found evidence of genetic adaptation to drought and seasonal environments by examining nasturtium and dry forest populations, ”said lead author and chair. Canadian researcher Amanda Melin, who has been studying the behavior and genetics of capuchin monkeys for almost 20 years.

Researchers have identified genes associated with the response to DNA damage, metabolism, cell cycle and insulin signaling. DNA damage is believed to be a major contributor to aging, and previous studies by Professor de Magalhaes and others have shown that genes involved in responses to DNA damage exhibit specific selection patterns. longevity in mammals.

“Of course, since genes related to aging often play multiple roles, it is impossible to know whether selection in these genes is related to aging or to other life cycle traits, such as growth rates and times. development, which in turn correlate with longevity, “says Professor De Magalhaes.

“While we need to be careful about the biological significance of our findings, it is tempting to speculate that, as with other species, changes in specific genes or pathways related to aging could contribute to longevity in capuchins.” , he added.

The team’s knowledge was made possible by the development of a new technique to more efficiently isolate DNA from primate faeces.

FecalFACS uses an existing technique that was developed to separate types of cells in body fluids – for example to separate different types of cells in blood for cancer research – and applies it to fecal samples from primates.

“This is a major breakthrough because the typical way of extracting DNA from feces results in approximately 95-99% of the DNA coming from gut microbes and food products. A lot of money has been spent sequencing the genomes of different organisms that the mammals that we are actually trying to study. Because of this, when wildlife biologists needed entire genomes, they had to rely on purer DNA sources, like blood, saliva, or tissue – but as you can imagine, these are very difficult to find by when studying endangered animals, ”explained lead author of the study, Dr. Joseph Orkin, who completed his work on this project as a postdoctoral researcher at the University of Calgary, and in its current location at the Universitat Pompeu Fabra-CSIC in Barcelona.

“FecalFACS finally provides a way to sequence entire genomes of free-roaming mammals using readily available, non-invasive samples, which could really help future conservation efforts,” he added.