Does one dog year really equal seven human years?  This long-held belief is undergoing some high-tech revision.

Scientists say a more accurate way to measure an animal’s age is to use something called an epigenetic clock—the accumulation of chemical modifications in an animal’s DNA over its lifespan.

One particular modification known as methylation is especially useful in tracking biological age.  DNA methylation has been used on humans and other animals, including mice, chimpanzees, and dogs.

Researchers at the University of California, San Diego have specialized in DNA methylation in dogs.  The researchers at UC San Diego studied over 100 Labrador Retrievers and found that their DNA methylation is somewhat similar to humans.

They also came up with an updated dog aging calculator, which shows that a dog’s “human age” can be calculated with a logarithm that multiplies a dog’s real age by 16, and then adds 31 to the total.

You can try the calculator HERE.

What does this new analysis of dog age mean?  Most dogs reach puberty at 10 months and live up to but not beyond 20 years.

The researchers found that a 7 week old puppy is roughly equivalent to a 9 month old human baby.  A 12 year old dog is roughly the same as a 70 year old human.

The researchers found that the canine epigenetic clock runs at a fast rate when a dog is young, then slows down somewhat as the dog grows older.

Scientists are hoping to apply DNA methylation to the study of how different dog breeds age, and also how certain diseases impact the various breeds.