Scientists have discovered a mutation behind pugs’ weird little flat faces

Image: Pixabay

So, I have what might be an unpopular opinion: there are cute dogs, and then there are pugs. With their squished little faces, buggy eyes, and snuffling breaths — there’s not much about pugs to recommend them (and I like dogs). But now, at least, scientists have a better idea about the genetics that make these little canines look like they ran face-first into a wall.

The category of squish-faced dogs, more correctly called brachycephalic dogs, also includes bulldogs, Boston Terriers, Shih Tzus, Pomeranians, and other breeds. Centuries of breeding have shortened their heads from front to back, and widened the roof of their mouths. The shape of their faces can make it hard for these dogs to breathe, and their bugged-out eyes are easily injured. A group of scientists and veterinarians wanted to find the genes responsible for these dogs’ flat faces. They published their investigation this week in the journal Current Biology.

Okay so maybe this one’s kind of cute.
Image: Pixabay

With the owners’ permission, the researchers took CT scans of 374 pet dogs that had been referred to their veterinary clinic. Using these scans, the researchers created 3D reconstructions of their faces so they could map and measure the dogs’ features. They found, unsurprisingly, that the extent of facial squishedness — when they controlled for dog size — tended to group with dog breed. On one end of the spectrum were the extremely snouty dogs, like smooth collies. On the other end of the spectrum: pugs.

The researchers also discovered genetic variations that tracked with the dogs’ face length. Several were especially common among the squish-faced dogs — including one mutation that suppresses a gene called SMOC2. The gene encodes a protein that helps cells stick to things, multiply, and rebuild tissue — in fish, it’s known to be important for normal facial development. The same appears to be true in dogs, the study reports. The more this mutation was able to suppress SMOC2, the flatter the dogs’ faces.

There are probably other genes involved, as well — the SMOC2 mutation accounted for only a little more than a third of the differences in face length that the researchers observed. The real proof would be to cut SMOC2 out of the DNA that normal-faced dogs pass onto their offspring, and see what percentage of their pups grow up to look like pugs. But, why would you want to make a perfectly cute doggo look like that?


Alternatively, could we not CRISPR the "long nosed" version of the gene in to fix pugs?

There’s no fixing pugs, they should just be left to die out. Stupid,stupid,stupid animals who have serious problems just breathing. Did I mention that they’re incredibly stupid

Of course pugs can be fixed.
I have one and she’s doing just fine. Her nose is longer than most pugs, she’s not overweight, she’s in the stables 5 days a week, she doesn’t snore any more than a regular dog (snores less so than my parents labrador and rottweilers).

Most pugs I meet do have problems, that is true, but there are breeders that work actively to purge the race of its genetic malfunctions. Granted, you’ll pay a hefty premium for a healthy pug, ours was $2500 and we had to wait for a year for her to arrive.
Lovely animals with a lot of character.

Like I’ve said above, I have one. I’d agree they have a decent personality, great with the kids but it’d stand by my statement 100%
Pugs are a breed bred through deformity which invariably causes a shittonne of problems later in life, and yes, stupid to the point of ridiculousness.
Far more humane to make the artificial breeding of such species illegal

Wouldn’t the same sentiment apply to a lot of other popular races? German Shepherds maybe?
Abolishing certain races seems drastic, the pragmatic solution would be to meticulously scrutinize dog breeders and only allow dogs with desirable health benefits to breed.

Our breeder has been active since the 70s breeding pugs and great danes, she’s incredibly thorough and only lets the dogs with desired traits (e.g. longer noses, healthy legs/spine) mate. Generations with healthier genetics pass on their genes, naturally allowing evolution to take its course.

No matter where a person stands there is also globalization to account for. Whatever legislation is enforced in one country won’t automatically apply in another. I doubt that we’ll ever be in a spot where the nations of the world band together to improve the health of dogs.

I think that anyone looking at a dog or cat (irrelevant of breed) should research the breeder and the dogs lineage. Inbreeding and the selfishness that exists today is a sad part of reality, the best course of action (IMO) is for potential dog owners is to always scrutinize their potential purchase. Over time, hopefully, healthier animals will be the norm.

The point is Pugs struggle to simply breathe. Breeding a species you know will suffer their entire life isn’t humane. On top of that they are surprisingly unintelligent. They do have a loyal personality however.

German Shepard do not struggle to breathe their entire life so the comparison isn’t a good one.

My avatar is my elder stateswoman pug Wednesday resting while young pup Fester watches intently. I call it "The Lazy Staredown."

Pugs are great for their personalities, not necessarily for their face folds or reverse sneezes or the like.

Go to the pound and pick out the ugliest mutt possible.

poor dog

There isn’t a breed of dog on Earth that isn’t cute, and pugs might just be the cutest among them.

I always thought they were ugly as shit until recently. They grew on me I guess. I’m a Labrador Retriever kinda guy.

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