What a Labrador DNA panel actually tests for

"Both parents are DNA tested" is a sentence that has stopped meaning very much. It appears on nearly every puppy advertisement, and it can describe anything from a full panel run by a laboratory to a cheek swab that came back with an ancestry pie chart.

Here is what the panel is supposed to cover for a Labrador, what each condition actually does, and the one distinction that decides whether a result matters.

Clear, carrier, affected

Everything below is recessive, which means a dog needs two broken copies of the gene — one from each parent — to be ill. One copy makes it a carrier: the dog is completely healthy, lives a normal life, and passes the copy to about half its puppies.

So a carrier is not a damaged dog, and a breeder who tells you they only ever breed clear-to-clear is either simplifying or quietly shrinking their gene pool for no benefit. What matters is the pairing. A carrier bred to a clear dog cannot produce an affected puppy. Two carriers bred together can, and there is no excuse for it, because the test costs less than a bag of food.

The question to ask is not "are they clear?" but "what were both parents' results, and what can this pairing produce?"

EIC — exercise-induced collapse

An affected dog is normal at rest and normal on a gentle walk. Under hard, excited exercise — the kind that happens in the fifteenth minute of a game of fetch — the back legs weaken and the dog goes down. Most recover within half an hour. Some do not recover at all.

It is common enough in the breed to be worth testing for in every single pairing, and it is invisible until the day it happens. This is the one that catches families out, because the dog that collapses is usually young, fit and having a wonderful time.

PRA-prcd — progressive retinal atrophy

The retina degenerates. Night vision goes first, usually in middle age, and the dog goes blind over months to years. It is not painful and dogs adapt remarkably well, but it is permanent and there is no treatment.

Worth knowing: the DNA test and the eye examination are not the same thing and do not replace each other. The DNA test says what the dog will develop. The annual eye examination finds what has already happened, including problems that have nothing to do with this gene.

CNM — centronuclear myopathy

A muscle disease that shows up in puppyhood. Affected dogs are weak, tire within minutes, lose muscle and tolerate cold badly. It does not kill them but it rules out anything resembling a normal life for a working breed.

DM — degenerative myelopathy

A progressive disease of the spinal cord in older dogs. It starts with the back feet knuckling over and scuffing, and advances to paralysis of the hindquarters over roughly six months to three years. It is not painful, which is the cruellest part of it — the dog is entirely itself and cannot walk.

The genetics here are less clean than the others: a dog with two copies will not certainly develop it, so the result is a risk rather than a sentence. It is still worth knowing before you pair two dogs.

HNPK — hereditary nasal parakeratosis

The least serious of the five and the most visible. The nose dries, crusts and cracks. It is manageable for life with ointment, and it is not going to shorten anything. We test for it because it is on the same panel and there is no reason not to.

What to do with this

Ask for both parents' results — all five, by name, with the laboratory that ran them. Then ask the breeder to tell you what the pairing can produce. If they can answer that without checking, they understand their own dogs.

The DNA panel is one of four things we clear a dog on before breeding it, and on its own it is the easiest of the four. Hips, elbows and eyes take longer and cost more, and we go through all of them on the health testing page. If you want to see what a pass looks like before you commit to anything, ask and we will send the certificates — that is answered along with nineteen other things on the FAQs page.