Discoveries

May 12, 2023

Special Traits

Listen to Today's Edition

Balto was a heroic dog, immortalized in a 1995 film with his name for delivering a lifesaving anti-toxin to a remote Alaskan town that was struck by diphtheria in 1925.

Now, this iconic Siberian husky’s DNA is offering new insight into how genetic diversity affects the health of dogs, both past and present, Scientific American reported.

In a new study, biologists found that Balto’s genome was more diverse and healthy than most modern breeds, suggesting that a population bred for work rather than aesthetics produces more genetically diverse and healthier dogs.

Balto was part of an imported population of Siberian huskies bred for speed, fitness, and relatively small size. Researchers sequenced DNA samples from Balto’s taxidermied specimen at the Cleveland Museum of Natural History and compared his sequences with those of current living dog breeds.

The canine’s genome showed that he had a phenotype that was optimal for Arctic survival, with adaptations that help digest starch, a trait that is not found in wolves but is relatively common in modern dog breeds.

But compared with modern dog breeds, the dog’s genome was less inbred, had more genetic diversity, and fewer potentially damaging genetic variations. The researchers suggest that selective breeding may be a factor in reducing genetic diversity and introducing harmful mutations among current dog breeds.

Overall, the study showed that genetic diversity confers more ability to adapt to environmental changes and stressors, which researchers use to measure genetic health.

Balto’s genome analysis is a part of the Zoonomia research project, which aims to understand the genetic diversity and evolution of mammals, and to apply findings to conservation efforts.

This story originally appeared in the May 12, 2023 newsletter, Strongman Down.