The Paw Print Genetics Blog

Breed of the Week: Siberian Husky

Breed of the Week: Siberian Husky

An iconic breed, the Siberian husky is often associated with Alaska, sled dogging and arctic temperature. Indeed, the husky dog is well suited to the arctic with an extremely thick double coat (said to be able to withstand temperatures as cold as -76 degrees Fahrenheit) and thick, fluffy sickle tail that aids in keeping it warm when at rest. It originated in northeastern Siberia (and was subsequently imported to Alaska), and was bred by the Chukchi people of northeast Asia. With their medium to large, well-muscled frame, the dogs have been used by indigenous people, explorers, miners and homesteaders to settle the coldest regions on the planet.

A member of the spitz group, the husky is just one of many sled-type dogs, which includes the Samoyed, Alaskan malamute, Alaskan husky and the Japanese Sakhalin husky, to name just a few. Members of the family all share the weather-resistant coat, as well as powerful and athletic bodies and high-energy levels. They were first used by the Inuit to pull sleds full of supplies and people, therefore aiding in the settling and inland exploration of Alaska, Canada and other places. European explorers then began using dog teams to pull sleds in their ...

Are Dalmatians the only breed to develop urate bladder stones?

Are Dalmatians the only breed to develop urate bladder stones?

It is no secret among many Dalmatian owners and their breeders that their beautiful breed is prone to developing bladder stones (uroliths) made of urates as they have historically been the poster puppies for the inherited condition, known as hyperuricosuria. However, many don’t realize that the same genetic mutation responsible for these stones has been reported in over a dozen breeds of dog, although at a much lower frequency.

Urates are formed from uric acid, a product of the breakdown of natural compounds of the body and from our food, known as purines. Affected dogs are predisposed to the formation of these bladder stones due to a mutation in the SLC2A9 gene1; a gene that serves as the blueprint for a protein responsible for transporting uric acid in the body. In dogs free of this mutation, this transporter plays an important role in transporting uric acid from the blood into the liver for degradation and from urine produced in the kidney, back into the blood. Affected dogs cannot perform these tasks adequately, thus resulting in a high level of uric acid in both the blood (hyperuricemia) and urine (hyperuricosuria). The disorder is inherited in an autosomal recessive fashion meaning ...

Breed of the Week: Pomeranian

Breed of the Week: Pomeranian

Descended from larger herding dogs, the Pomeranian is a spitz-type dog that is now a companion and show dog in the toy group. Its small size makes it a great choice for apartments or houses with small yards as it doesn’t need much exercise, but the small dog is very energetic and requires attention from its owners. The Pomeranian’s popularity began in the late 1800s with British royalty and continues to this day.

The modern breed is believed to have developed in a region of northern Germany and Poland that is known as Pomerania, and that it was used as a herding dog. In this working form, the breed was approximately 30 pounds (and perhaps weighed as much as 50). The early iteration of the breed, which came from the German spitz, worked in harsh northern climates (even earlier versions were used in the arctic) and gives the current breed its thick double coat, which protects it from the cold, wet, windy elements.

Pomeranian popularity soared in 1891 when Queen Victoria showed a small, 12-pound dog named Windor’s Marco. The smaller size immediately became all the rage and breeders began selectively choosing mates based upon their miniature dimensions. It is ...

Mitochondrial Inheritance is Responsible for Canine Disease

Mitochondrial Inheritance is Responsible for Canine Disease

My last two articles on dominant and recessive inheritance and X-linked inheritance have built upon each other and discussed different types of inheritance: dominant, recessive and X-linked.  These three modes of genetic transmission are fairly straightforward compared with the topic of today’s post, which is mitochondrial inheritance.  Maybe you’ve never heard of the word “mitochondria” before.  Or perhaps just reading the word brings you back to high school cell biology.  While this may be a rare form of inheritance, diagnosing a dog with a mitochondrial disorder may impact how breeders choose to breed their animals.

Before we discuss the mitochondrial inheritance, let’s talk about mitochondria. Just like our bodies need organs to function (kidneys, heart, liver, etc.), cells have organelles too.  One of the organelles is called a mitochondrion or mitochondria (plural).  Mitochondria are the energy powerhouses of the cell.  They create energy through a series of biochemical reactions.  The number of mitochondria can change depending on the type of cell (muscle, nerve, skin, etc.). 

The neat thing about mitochondria is that they have their own set of DNA, called mtDNA, separate from the DNA found in the nucleus; mtDNA is ...

Paw Print Genetics: A new approach to canine inherited disease testing

Paw Print Genetics: A new approach to canine inherited disease testing

The pointing Labrador is just one of many exceptional dog breeds. Versatile in their ability to point, flush and retrieve, pointing Labradors may be the perfect hunting companion.  How a specific dog breed has so many desirable characteristics is not a mystery. All domesticated dogs were bred for specific behavioral or physical traits that were required for certain jobs – whether it was for chasing and catching varmints, retrieving the evening’s dinner, or bringing in the herd, dogs are the perfect species for a variety of tasks.  

All of these traits, behavioral and physical, have a genetic component and are determined by an accumulation of genes with modifications, or mutations, that result in some outcome. Whether the traits are pointing, coat color or skull structure, humans chose founding stock to create the various breeds and bred these dogs for the traits they desired.  However, undesirable, even harmful genetic mutations were carried along in these breeds. The most ancient mutations can be found in many breeds of dogs, whereas those mutations that arose more recently maybe found in only one or two breeds.

With the advent of molecular genetic technologies and the sequencing of the domestic dog (Canis ...

Breed of the Week: Deutscher Wachtelhund

Breed of the Week: Deutscher Wachtelhund

The Deutscher wachtelhund, or German spaniel, is a medium-sized, thick-boned, muscular gun dog with a thick wavy coat that protects it from briars and cold water. While they’ve been around since the 1700s, they’re a little-known versatile gun dog in both the United States and its home country of Germany.

In the U.S., the wachtelhund was recognized by the UKC in 1996, and the breed standard was published in 2004. The AKC is currently accepting applications for its Foundation Stock Service, which requires acceptance from a domestic or foreign registry. In the case of the wachtelhund, that registration comes from the German Wachtelhund Club, which oversees the Deutscher Wachtelhund of North America, and has very strict criteria for acceptance. In Germany, the wachtelhund has only been allowed to be owned by hunters, gamekeepers and foresters – few citizens even know of the breed.  

While the wachtelhund has a spaniel look (in both size and appearance), and they do flush feathered game, they are a versatile breed that is expected to hunt not just birds but also furred game such as rabbits and foxes – and even bigger game like stag and wild boar. They tend to air scent ...

Dirty Dozen: Best Dog Breeds for Winter

Dirty Dozen: Best Dog Breeds for Winter

Almost all dogs are better suited for the cold than humans – it’s just the way they’ve evolved. However, some breeds are better suited for the cold, rain, snow and ice than others. These breeds historically served a purpose that had to do with cold, nasty weather, climates or conditions.

Three breed groups feature several dogs that tend to fall into the winter-loving category and have some unique features that help them adapt to cold climates – namely double coats (those featuring an insulating under layer and weather-resistant outer layer) that were developed to repel the elements.

It’s something to keep in mind if you’re considering a new dog. These dogs tend to be happy and at home in colder temperatures, and if you live a hot area (like the desert southwest) they might not fare as well as in more northern climes or higher elevations where cooler weather is more prevalent.

Retrievers

Breeds such as the Labrador, Chesapeake and golden retriever were developed to fetch fishermen’s nets and hunters’ waterfowl from rough, icy seas.

As such, retrievers tend to have an outer coat that is slightly oily, which helps repel water while trapping air and body heat while submersed ...

Breed of the Week: Brittany

Breed of the Week: Brittany

The Brittany is a medium-sized bird dog that originated in France in the 17th Century. They were an all-purpose game dog in Europe, and were expected to hunt, point and then retrieve game – everything from feathered prey to furred game such as rabbits.

Once known as the only pointing spaniel, the term ‘spaniel’ was dropped from its name in 1982 because of such conspicuous differences in hunting styles; Brittanys point, while spaniels such as the cocker and English springer flush game.

Topping out at 20-1/2 inches and 50 pounds, the Brittany comes in several coat colors – orange and white or liver and white in either clear or roan patterns. The coat is a single coat, as opposed to a double coat like spaniels or retrievers (dense, insulating undercoat and weather-resistant outer coat), which makes it easy to maintain, and it’s usually dense and either flat or wavy. The tail of the Britt is short; if puppies are born with a long tail, it’s usually docked to the appropriate length – especially if it’s meant to work in the field.

Brittanys are an energetic, athletic dog that are rockets in the field – they’ll work tirelessly in ...

Beyond Dominant and Recessive: X-Linked Canine Inheritance

Beyond Dominant and Recessive:  X-Linked Canine Inheritance

My last blog talked about the basics of two types of inheritance for genetic conditions found in dogs: dominant and recessive.  To review, dominant conditions need one copy of the mutated gene in order for the dog to show symptoms.  Recessive conditions need both copies of the mutated gene inherited from each parent to have the disease.  Knowing the difference can change the way breeders choose which dogs to breed.  However, the wonderful world of genetics is not that simple.  Another pattern of inheritance is called X-linked, or sex-linked.  Although it is not as common as dominant and recessive; it is important to know which diseases follow this inheritance pattern, because it may impact breeding.

Dogs have 39 pairs of chromosomes (humans have 23).  Something dogs and humans have in common is the X and Y chromosomes determine gender.  XX is a female while XY is a male.  Females always give away an X chromosome to their offspring.  So, it is the male that determines gender for the next generation.  If he passes on the X chromosome, the offspring is female.  If he passes on the Y chromosome ...

Training: Anticipating Problems and Positive/Negative Reinforcement

Training: Anticipating Problems and Positive/Negative Reinforcement

Great trainers don't just run drills or take their dogs into a field and let them chase birds. Great trainers start each session with a goal and specific task to accomplish. They set up drills and scenarios that help teach the dog bits and pieces of a larger concept. By micro-focusing on areas that might prove problematic to the dog, they can anticipate trouble and administer well-timed corrections, praise or avoid the issue altogether.

If you're not anticipating how your dog is going to behave to a situation, you're not really training; you're just reacting. If your dog makes a mistake because you didn't anticipate the problem, you're effectively teaching him to do it wrong. To train after reaching that point requires that you correct the dog to teach him that's not what you wanted.

Sometimes negative reinforcement is the way to go and what is required, but to wholly rely on it is not only lazy, it's unfair to your dog.

With a balance of positive and negative reinforcement properly administered, you can teach your dog how to react to very complex scenarios. And, as George Hickox and Dan Irhke both pointed out at a ...