February 23, 2024


A pioneering project has seen hundreds of scientists around the world unravel many of the mysteries of mammalian evolution, work that may help us understand why humans are unique and which specific genetic changes are key to disease.

this animal source projectwhich began in 2015, has grown to include more than 150 researchers from 50 institutions and feature the genomes of 240 diverse and specialized mammal species, representing approximately 80 percent of the mammalian families on Earth.

Of course, this number is just the tip of the iceberg, there are more than 6,000 species of mammals on Earth today. The collection includes an elephant, 43 primates, 53 rodents and more than 100 other species, representing less than 1 percent of all living mammals.

However, the first results of this epic global collaborative project are published in 11 studies in the journal scienceand more are expected.

“These 11 papers are just a sampling of the types of science that can be done with new genetic data,” said researcher Beth Shapiro, professor of ecology and evolutionary biology at UC Santa Cruz. “They demonstrate the true importance of these large coalitions and underlying datasets.”

One of the studies traces the famous evolutionary story Siberian Husky Balto, who was part of a rescue dog sled team delivering antitoxin to a remote town in Alaska, collapsed in 1925 from diphtheria. He was the inspiration for the 1995 animated film of the same name and can now be seen in his statue-form park in downtown New York.

“Balto’s fame and the fact that he was taxidermied gave us this cool opportunity 100 years from now to see what the genetics of the sled dog population looked like and compare him to modern day dogs,” said the first Author Katherine Moon, a postdoctoral fellow at the institute, said. UC Santa Cruz.

Through this study, the scientists were able to see that the Balto, a small, fast and healthy sled dog from Siberia and with more genetic diversity than modern breeds, may have evolved genetic variations to adapt to the harsh Alaskan conditions of the 20s .

“The genetic variation in Balto is associated with things like weight, coordination, joint formation and skin thickness, and you’d expect a dog to run in that environment,” Moon said.

“It’s really interesting to see the evolution of a dog like the Balto, even over the last 100 years,” she added. “The Balto population was distinct from the modern Siberian Husky, which was bred to physical standards, but also from the modern working Alaskan Malamute.”

The genomes of the 240 species of mammals vary wildly, from the common curved-winged bat with nearly 2 billion chemical base pairs that make up its genetic map, to the screeching hairy armadillo with 5.3 billion base pairs. Humans sit somewhere in the middle, just over 3 billion.

Comparing so many species provides the first comprehensive look at the evolutionary timelines of different species, how they specialize for survival and which common genes persist, giving scientists clues about their role in mammalian survival. importance.

exist another studyco-lead authors Megan Supple and Aryn Wilder, Howard Hughes Medical Institute (HHMI) scientists at San Diego Zoo Wildlife Alliance, used the International Union for Conservation of Nature’s Red List of Threatened Species The 240 mammal species in the project are ranked by risk of extinction. They then search for genetic clues to explain their contemporary place on Earth, and quickly and cheaply identify those species most at risk of extinction.

“We know we’ll never have enough conservation money to go around, but even with a single genome, we can classify species,” said co-author Shapiro.

elsewhere, another study See a collaborative team study over 10,000 parts of the genetic code found in all other mammals, but not humans, in an effort to figure out why we are such a special breed.

“We usually think that new biological functions must require new stretches of DNA, but this work shows us that deleting the genetic code can have profound effects on traits that make us a unique species,” said senior author, Assistant Professor of Genetics Steven Reilly said. Yale School of Medicine.

Scientists have identified key deletions near genes associated with uniquely human disorders such as schizophrenia and bipolar disorder. Understanding these changes opens the door to a better understanding of human diseases and, in turn, the development of new, targeted treatments for them.

“[Deletions like this]could fine-tune the meaning of instructions on how to make a human, helping to explain our larger brains and complex cognition,” he said. “These tools allow us to begin to identify many of the things that make us unique as a species.” small molecular building blocks.”

In other papers, the scientists isolated parts of the genome associated with traits such as large brain size, a keen sense of smell and successful hibernation. Elsewhere, scientists found more concrete clues that mammals had begun to evolve and diversify before the asteroid that wiped out the dinosaurs hit Earth about 65 million years ago and continued to change after it, but at a faster rate much.

Researchers hope to add more genomes to zoonotic disease datasets, currently one Vertebrate Genome Project More than 70,000 different organisms are expected to be genetically mapped.

11 research papers published in special issue science.

To learn more about how Project Zoonomia came to be, watch the video below:

(embed) https://www.youtube.com/watch?v=LUF3BfvA_f0 (/embed)

How Zoonomia researchers learned from the genomes of 240 mammals

source: animal source project, Howard Hughes Medical Institute, Yale University, Broad Institute