Cornell researchers have successfully produced a litter of healthy puppies via in vitro fertilization. In a study published in the journal Public Library of Science ONE, the team explains how this breakthrough could allow for the better conservation of endangered canine species.

Dogs are just as susceptible to heritable diseases as humans. Indeed, the two species actually share more than 350 genetic disorders – more than any other species pair. Using gene-editing techniques, scientists were able to alter the genetic makeup of the puppy embryos.

“Since the mid-1970s, people have been trying to do this in a dog and have been unsuccessful,” said Dr. Alex Travis, associate professor of reproductive biology in the Baker Institute for Animal Health in Cornell’s College of Veterinary Medicine.

The genes of beagles and cocker spaniels were combined in a lab and transferred to a host female dog, who gave birth to seven healthy puppies on July 10. The pups are now five months old.

“We each took a puppy and rubbed it with a little towel and when it started to squiggle and cry, we knew we had success,” said Dr. Travis. “Their eyes were closed. They were just adorable, cute, with smooshed-in faces. We checked them to make sure they looked normal and were all breathing.”

The experiment’s success has greater implications than the creation of adorable puppies. The Cornell team hopes their breakthrough method can be used for other endangered wildlife species in order to help bolster populations.

“We can freeze and bank sperm, and use it for artificial insemination,” said Travis. “We can also freeze oocytes, but in the absence of in vitro fertilization, we couldn’t use them. Now we can use this technique to conserve the genetics of endangered species.”

Moreover, the myriad similarities between canine and human inheritable diseases means that this strategy of gene editing could potentially be a “powerful tool for understanding the genetic basis of diseases.”

“With a combination of gene editing techniques and IVF, we can potentially prevent genetic disease before it starts,” said Travis.

The Cornell study was funded by the National Institutes of Health, Cornell’s Atkinson Center for a Sustainable Future, the Smithsonian Institution, and the Baker Institute for Animal Health.