A wolf dog is any canine with both domestic dog and wolf in its recent genetic ancestry and can result from any of the following parent combinations: a pure wolf and a pure domestic dog, a pure wolf and a wolf dog, two wolf dogs, or a wolf dog and a pure dog. Any breed of dog or subspecies of wolf are capable of producing viable offspring, though the chances of a toy poodle-wolf mix is extremely unlikely without human intervention in the breeding process due to the size difference between the parents.

 

Though it comes as a surprise to many, wolf dogs are almost exclusively a consequence of human manipulation. In the wild, wolves are generally, though not always, monogamous and extremely territorial by nature, viewing most other canines (wolves outside their pack, coyotes, and dogs) as competition for the resources necessary to survive. As a result, most wild wolves would likely react aggressively to a dog entering their territory, chasing them away or attempting to kill them rather than accepting them into a pack or viewing them as a potential mate. In addition, both male and female wolves are only capable of breeding once a year, so the likelihood of a free-ranging dog encountering a wild wolf of the opposite sex alone during breeding season (sometime between January and March) is very low.

 

So, if this is not a naturally occurring phenomenon, why do people intentionally create wolf dogs? There are numerous reasons, ranging from wanting to control a piece of the wild to mistakenly believing that they are creating a better “guard dog” to simply liking the “wolf look.” There is a misconception that breeding wolves and domestic dogs together will create the ideal blend of wild and domestic traits in the pups. However, these attempts to “reinvent the dog” hardly ever result in the ideal creature that most people are looking for.

WOLF DOG VS. WOLF HYBRID

It is quite common to hear the terms “wolf dog” and “wolf hybrid” used interchangeably to describe an animal with both wolf and dog genes. While both are technically correct, the term “hybrid” is considered to be the less desirable label for these animals. This is because many hybrids, such as the mule, are sterile as a result of the two parent species having differing numbers of chromosomes. However, since wolves and dogs are closely related genetically (sharing over 99% of their DNA) and have the same number of chromosomes, wolf dogs are an example of an intraspecific hybrid (a hybrid at the sub-species level), which are capable of producing viable offspring. Since they are inherently fertile, “wolf dog” is more commonly used.

WHAT IS WOLF CONTENT?

When you hear people talking about wolf dogs, you will almost always hear the term “content” being utilized, such as an someone claiming that, “My wolf dog is high-content,” or, “That wolf dog is low-content.” But what exactly is “content?” Essentially, the term “content” refers to the ratio of wolf genes to dog genes in a particular animal’s DNA. A high-content individual will have predominantly wolf genes with minimal dog genes. A low-content individual is just the opposite, with the majority of the genes being those of dogs with a lower amount from wolves. Mid-content refers to animals that contain a relatively equal amount of both wolf and dog genes. While the specific ranges of what is considered to be high-content, mid-content, and low-content vary dependent on the source, low-content animals are typically considered to be those individuals whose genome contains less than 50% wolf DNA. The definition of mid-content varies, ranging from 50% to 75% or 50% to 85% wolf DNA, reserving the high-content label for animals that fall above the mid-content range that are not pure wolves.

 

However, when most people talk about wolf content, there is oftentimes no scientific or biological basis for their assessment. Instead, it is simply a guess or a reflection of what they want to believe to be true. The reasons for these beliefs vary greatly, including secondhand information provided about an animal, the presence of wolves in the geographic location from which that animal came, physical resemblance to a wolf, and destructive or inappropriate behaviors. However, true wolf content is determined by the DNA inherited from an individual’s parents and ancestors, regardless of these other conditions.

While studying the way genes are inherited and expressed is a complicated science with millions of variables, in its most basic form for mammals, one half of an individual’s genome is inherited from each parent. This, of course, holds true for wolf dogs. However, the chances that two gametes (egg or sperm) are 100% identical is exceptionally low, and as a result, it is rare for two individuals to be 100% identical. This is because of the random crossing over of genes between paired chromosomes during the production of gametes. Therefore, it is impossible to accurately predict the wolf content of any one wolf dog pup, let alone an entire litter, based on the known content of the parents, except in one particular circumstance. The only way to know the exact content of a wolf dog is to breed a pure wolf and a pure domestic dog. In this situation, all of the pups will be 50% wolf and 50% dog.

Many people mistakenly believe that using simple math is a good predictor of wolf content for other parent combinations. For example, if one parent is 50% wolf and the other is 100% wolf, most people assume the pups will all be 75% wolf. However, genetics is far from that simple. Between the backcrossing with other wolves, dogs, or wolf dogs and the unique, random genetic crossover that occurs with the production of each individual gamete, there are millions of potential genetic outcomes for wolf dogs. For example, it is theoretically possible that if two fifty-fifty wolf dog crosses were bred, there could be pure wolf, pure dog, and wolf dog siblings in the same litter of pups. While this is a highly improbable situation, the fact that it could technically occur illustrates the complexity of determining exact content of wolf dogs. There will be a range of wolf content in any single litter of wolf dog pups unless the parents are a pure wolf and a pure dog.

While selective breeding can increase the chance of some observable traits being expressed more frequently, the overall underlying genetic makeup of an individual is independent of conscious, external control. Therefore, it is important to realize that selecting for certain traits can have unseen or unintended outcomes.

HOW IS WOLF CONTENT DETERMINED?

Assigning wolf content to an individual can be be very challenging. There are three methods with which wolf content can be judged: physical, behavioral, and genetic characteristics. The genetic component will be discussed in a latter section. It is important to note that determining an animal’s content based solely on one of these components is unlikely to yield accurate results.

 

Using physical characteristics to identify wolf dogs is known as phenotyping. There are dozens of physical features that can be used to distinguish between wolves and dogs including the shape and color of the eyes, the width of the chest, the shape of the muzzle, the length of the legs, the size of the paws, and numerous others. Phenotyping can be a difficult tool to use in identifying wolf dogs if not extremely familiar with how pure wolves look, as many dog breeds can have some features that are similar or even identical to those found in wolves. For example, a golden eye color is not unique to wolves. Thus, a golden eye color does not necessarily indicate that an animal has wolf content. Additionally, there are numerous domestic dogs that have been intentionally bred to resemble wolves, which can cause further complications in distinguishing between the two.

 

There can be similar issues using behavior to identify wolf dogs. One must have a keen understanding of how wolf and dog behaviors differ from one another to be able to use this strategy, and even this can be inaccurate. It is important to note that both an individual’s genetics and previous experiences contribute to its behavior. For example, a feral or poorly socialized dog may demonstrate cautious or flighty behaviors often observed in wolves, or a well-socialized wolf may be friendly and outgoing like a dog. Just because an animal acts “wolf-like,” does not necessarily indicate that the animal has wolf content.

 

In general, most sanctuaries and wolf dog experts use both physical and behavioral cues when assessing the content of a suspected wolf dog. As a result, they will not assign percentages to a wolf dog. Instead, they will assign the wolf dog into one of four basic categories: no-content, low-content, mid-content, and high-content.

This is a no-content wolf dog, meaning it is a domestic dog and has no recent wolf DNA.

This is a low-content wolf dog, meaning it has a low percentage of wolf DNA compared to dog DNA.

This is a mid content wolf dog, meaning it has a similar precentage of wolf DNA and dog DNA.

This is a high content wolf dog, meaning it has a high percentage of wolf DNA compared to dog DNA.

WHAT ABOUT DNA TESTING?

DNA testing is the third way of identifying a wolf dog and will often, though not always, give a percentage wolf content with the results. While DNA testing is considered by many to be the most accurate assessment, it is very important to understand that not all DNA tests or laboratories are equally accurate, nor do they all use the same methods and techniques to assess wolf content. Some look at the whole genome while others pick only a few genes to evaluate. Some labs use very recent techniques, while others may use older or rapid but less accurate methods. Some use a cheek swab to get DNA, others use blood samples, and some use hair or feces. Many labs also only use their own wolf reference data rather than a universal set to which to compare results. These variations can lead to large discrepancies in the reported results, and, just like with physical and behavioral assessments, all DNA results should be looked at with a critical eye and the acknowledgement of the potential for error.

When selecting a laboratory to run a DNA test on a suspected wolf dog, it is very important to research the outfit offering the test before submitting one. Do not simply default to the cheapest or most convenient test available. Firstly, ensure that the test looks for wolf DNA, as many consumer dog DNA tests do not. Additionally, research the lab’s test methods and how accurate they are. What type of sample needs to be submitted? How much of the genome is sequenced to determine the content percentage? How are their results are reported? Some DNA labs are not detailed enough to give percentages and will simply respond with the labels “wolf,” “wolf dog,” or “dog” as their results. Finally, look at comparison reviews between the tests available to help determine which is the most accurate.

COMPARING PUBLICLY AVAILABLE DOG DNA TESTS

As an experiment, DNA samples from two of W.O.L.F.’s resident wolf dogs, Kira (a low-content, pictured left) and Yuki (a mid-content, pictured right), were sent to different laboratories that provide dog DNA sequencing services. Four labs used a cheek swab DNA sample, each with slightly different collection tools and instructions, while the fifth required a blood sample. Each lab also used their own DNA extraction and amplifying techniques as well as analysis algorithms. None of the DNA results matched, each reporting different breed mixes and percentages.

DNA Test Result For Kira

Laboratory 1

71.7 % Domestic Dog

28.3%  Wolf

Laboratory 2

38.6%  German Shepherd

22.4%  Alaskan Malamute

14.6%  Siberian Husky

12.7%  Samoyed

11.7%  Gray Wolf

Laboratory 3

23%  Alaskan Malamute

20%  German Shepherd

16%  Wolf

15%  Siberian Husky

11%  Kai Ken

8%  White Swiss Shepherd

5%  Canaan Dog

1%  Swedish Vallhund

1%  Lhasa apso

Laboratory 4

61% to 99%  German Shepherd

10% to 25% Samoyed

10% to 25%  Wolf Hybrid

Laboratory 5

25% Alaskan Malamute

25% Breed Unknown

12.5% Siberian Husky

12.5 % White Swiss Shepherd

12.5%  Wolf

12.5% German Shepherd

DNA Test Results For Yuki

Laboratory 1

Not Tested

Laboratory 2

57.4%  Gray Wolf

19.8% German Shepherd

14.0% Alaskan Malamute

8.8% Siberian Husky

Laboratory 3

48%  Wolf

18% White Swiss Shepherd

15% Alaskan Malamute

9% Siberian Husky

6% German Shepherd

4% Coyote

Laboratory 4

26% to 39%  Alaskan Malamute

26% to 39%% Samoyed

26% to 39% Akita

10% to 25%  Wolf Hybrid

Laboratory 5

50%  Wolf

25% White Swiss Shepherd

12.5% Alaskan Malamute

12.5% Siberian Husky

SOURCES

“WOLF-DOG HYBRIDS.” International Wolf Center, https://wolf.org/wolf-info/basic-wolf-info/wolves-and-humans/wolf-dog-hybrids/.

 

“What is Phenotyping.” Texas Wolfdog Project, https://texaswolfdogproject.org/resources/phenotyping/what-is-phenotyping/.

 

“Effective Wolfdog Phenotyping.” Dark Forest Group, 27 October 2003, http://thedarkforestgroup.com/files/Effective_Wolfdog_Phenotyping_w97watermarked.pdf.