When one dog owner shared photos of their 12‑pound puppy online, most viewers thought they were looking at a classic small-breed mix—something like a Jack Russell terrier, with tidy proportions and button-adjacent ears. The owner thought so too, and was in for a surprise when the canine’s DNA results arrived.
“I’m floored! I am shocked!” the owner wrote in a now-viral Reddit post. “I thought for sure I had a little Jack Russell/rat terrier mix but these DNA results are crazy.”
The post, shared to Reddit under u/No-Marionberry5759 on March 29, has since been upvoted more than 1,000 times, drawing amused and affectionate reactions from viewers who were equally surprised by what the genetic test revealed. Alongside a carousel of photos showing the puppy’s compact frame and expressive face was a screengrab from an Embark DNA results page—evidence that upended expectations.
At just 4 months old, the puppy weighs just 12 pounds and looks, at first glance, like a small terrier mix. The dog has black, white and ginger coloring, with pointed ears that flop softly at the tips, reinforcing the impression of a breed known for its compact size and boundless energy. But the DNA results told a very different story.
According to the Embark test, the puppy is made up of 41.9 percent Labrador retriever, 25.3 percent treeing walker coonhound, 15.7 percent German shepherd dog, 11.1 percent “supermutt” and 6 percent Newfoundland. In other words: there are all large breeds, many known for growing into dogs that far exceed the size of a typical Jack Russell terrier.
“All big dogs with no button ears,” the owner added in the post. “My little guy is 12 pounds at 4 months of age, and I just don’t see him getting up to 40-60 pounds! Wild!”
The contrast between appearance and genetics struck a chord with viewers on Reddit, many of whom chimed in with their own stories of dogs who defied breed expectations—either staying much smaller than predicted or suddenly hitting late growth spurts that transformed similarly “little guys” into large, lanky adults.
“He reminds me of my dog when he was that age,” one viewer said. “I was convinced he was part JRT at one point. But he just kept growing over the next year. He’s now 3 1/2 and about 32 lbs. His mix is Chi, pit, chow, poodle and a few other things. I think your pup hasn’t hit his growth spurt yet. Larger dog breeds continue to grow for up to 2 years.”
“My dog was 15 pounds at 4 months old,” another added. “She is about 55 pounds now at 8 months old. She is 64 percent APBT [American pit bull terrier], 19 percent Bloodhound and 17 percent Great Pyrenees. Growth spurt hit about 5 or 6 months old.”
“You’ve got a copy of my girl. My beautiful girl that I also did DNA testing on and got no JRT,” a third viewer shared. “They estimated ~40 — ~60 at the vet too and she is 20 pounds.”
Part of the fascination lies in how canine genetics express themselves. A puppy can inherit physical traits that mask its eventual size, especially at a young age, while still carrying the genetic blueprint of much larger breeds. In this case, the presence of Labrador retriever, German shepherd and Newfoundland DNA suggests the potential for significant growth ahead—even if the puppy’s current proportions suggest otherwise.
For now, the owner’s disbelief remains part of the charm. Whether the pup stays small or grows into the larger lineage hinted at in the results, the Reddit community seems united on one point: no matter the size, the dog is already a winner.
Newsweek reached out to u/No-Marionberry5759 for more information via Reddit.
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