It’s almost common knowledge for all dog owners to know their beloved pooches’ ages in human years.
After all, it’s supposed to be your dog’s age multiplied by the number seven. So one human year is equal to seven dog years, right?
Well according to the U.S. National Institute of Health (NIH), the real formula changes over time.
So we could have been wrong all along.
In a research studying the biological changes to dog’s genomes over the course of their lives, scientists used epigenetics (a process in which modification occurs in the genome) as a biological marker to study the aging process.
The study identified a similar trait among dogs and humans, the developmental timeline that begins with birth, infancy, youth, puberty, adulthood, and finally, death.
And as we reach these different stages along with our doggos, the chemical marks on our DNA changes accordingly.
As we grow into the next stages of our lives, molecules called ‘methyl groups’ attach themselves to certain regions of our DNA and switch them into the “off” position.
According to the NIH, these patterns are what allows us to accurately gauge a person’s age. They’re also known as “epigenetic clocks.”
Trey Ideker, who is the senior author of the study published in Cell Systems, compared the patterns to wrinkles.
“I tend to think of it very much like when you look at someone’s face and guess their age based on their wrinkles, gray hair, and other features,” he said, according to Malay Mail.
But so far, these epigenetic clocks are only truly successful in predicting human age.
To understand the epigenetic clocks in other species, scientists decided to research the lifetime of a domestic dog due to the fact that their environment, diet, physiological, and developmental patterns are similar of that of humans.
“Dogs experience the same biological hallmarks of aging as humans, but do so in a compressed period, around 10 to 15 years on average, versus over 70 years in humans,” Dr. Elaine Ostrander, NIH Distinguished Investigator and co-author of the paper, said.