5 Noteworthy Genome Findings Out of 240 Research Candidates as Reviewed by 100 Experts

100 experts carefully inspected 240 research papers and chose the top five genome discoveries.

240 Research Candidates and 100 Experts

Around 100 experts from different countries have examined genetic data from 240 different mammalian species. Using the data, researchers can begin to address queries about human disease, the brain, the evolution of mammals and other topics.

In 11 studies published in the April 28 issue of the journal Science, the team behind the Zoonomia Project describes DNA collection from species throughout the mammalian family tree, which includes an aardvark, a human, a fat-tailed dwarf lemur, and a tapir.

The vast collection of DNA "letters" that make up an animal's genome, or genetic instruction manual, are read out by scientists for each of those mammals. This work was first described in the journal Nature in 2020. The group then arranged the text from each mammal's book in a line and searched for discrepancies.

Elinor Karlsson, a geneticist at the Broad Institute and the University of Massachusetts Chan Medical School, claims that DNA regions that have undergone a great deal of change can provide information about how a species is adjusting to its environment. The 240 studied species only make up 4% of all mammals, so there is still much to learn about the evolution of mammals.

The group of researchers found five noteworthy studies on the mammal genome.

Sled Dogs in the Harsh Conditions of Alaska

Balto, a famous sled dog who helped deliver medicine during a diphtheria outbreak in 1925, was part of a population of sled dogs that had adapted to the harsh conditions of Nome, Alaska. An analysis of Balto's DNA revealed that he had an enhanced ability to digest starch and carried fewer potentially damaging mutations. Furthermore, the study suggested that he was less inbred than modern dogs, indicating a genetically healthy population. The researchers also discovered gene variants linked to bone and skin development that could have given Balto tough foot pads, helping him endure the cold and ice.

Placental Mammals from 10s Million Years Ago

A new analysis suggests that the origin of placental mammals may date back to 102 million years ago, contradicting the traditional view that mammalian evolution began after an asteroid wiped out the dinosaurs 66 million years ago. The study proposes that mammalian evolution started when the continents were breaking apart, and new species continued to evolve over time, even after the Cretaceous Period's end.

Identifying Cancers

In people with cancer, scientists can find mutations speckled through the genome. The Zoonomia Project's data could help identify important cancer mutations. As cancers develop, mutations accumulate, but determining which ones drive the disease is challenging. One study focused on mutations in stable parts of the mammalian genome, which are likely essential for health. A mutation in these areas could be a key change that sets off cancer and identifying them could aid in developing treatments.

Jumping Genes in Mammals

A Zoonomia study estimates the proportion of the genome that is mobile in mammals and suggests that an animal's diet could play a role. The researchers found that aardvark genomes contained the most "jumping genes," comprising nearly 75% of the animal's genome. Additionally, meat-eating mammals tended to accumulate more of a particular type of jumping gene, which suggests that an animal's ecology and diet may shape the evolution of its genome.

Faster Evolution in Humans

A Zoonomia study analyzed regions in human DNA that has undergone a lot of changes, which represent areas evolving faster in humans than in other mammals. These regions were found to be physically close to genes involved in brain development due to the way the human genome folds up. This proximity could increase gene activity, potentially changing the way the human brain works, although the specific effects are not yet known, Science News reports.