CAMBRIDGE, Mass. — Scientists have revealed a comprehensive map comparing the DNA of 240 mammalian species, a breakthrough that could revolutionize medicine. The genomes, which represent complete sets of genetic information, highlight crucial elements of human DNA that have remained consistent throughout millions of years of evolution.
The Zoonomia Project, one of the most ambitious undertakings in biology to date, features a wide array of animals, from aardvarks and African elephants to yellow-spotted rock hyraxes and zebus. Over 150 individuals from seven different time zones have contributed to this unprecedented resource.
“One of the biggest problems in genomics is that humans have a really big genome and we don’t know what all of it does. This package of papers really shows the range of what you can do with this kind of data, and how much we can learn from studying the genomes of other mammals,” says lead author Professor Elinor Karlsson from the Massachusetts Institute of Technology, in a media release.
Over the past 100 million years, a myriad of mammals have adapted to nearly every environment on Earth. The findings offer insights into how some species perform extraordinary feats. They also aid researchers in better understanding which parts of our genome are functional and how they might influence health and disease.
Researchers identified regions of genomes, sometimes consisting of single DNA letters, that are most conserved and therefore likely to be biologically significant. Some are associated with unique traits such as hibernation ability or keen olfactory senses. Others increase the risk of extinction due to climate change and habitat loss. Certain mutations make humans more susceptible to both rare and common diseases.
An international team analyzed DNA samples collected from over 50 institutions worldwide. Many of these samples were sourced from the San Diego Wildlife Alliance and comprised genomes from species that are threatened or endangered.
The majority of the conserved regions, which have evolved more slowly than random fluctuations, are involved in embryonic development and gene expression regulation. Regions that have undergone more frequent changes typically influence an animal’s interaction with its environment, for instance through immune responses or skin development. The researchers discovered that mammals with fewer genetic changes at conserved genome sites were at higher risk of extinction.
Study authors leveraged the mammalian genomes to study human traits and diseases. They identified variants linked to diseases, including cancer. An examination of over 10,000 genetic deletions specific to humans, using both Zoonomia data and experimental analysis, connected some deletions to the function of neurons.
“We’re very enthusiastic about sequencing mammalian species. And we’re excited to see how we and other researchers can work with this data in new ways to understand both genome evolution and human disease,” adds co-author professor Kerstin Lindblad-Toh, from Uppsala University in Sweden.
The findings of the Zoonomia Project is a series of 11 studies published in the journal Science.
South West News Service writer Mark Waghorn contributed to this report.