Tag archives: dna dog test

Canine coat color and traits are determined by the interaction of multiple genes, each responsible for a specific inherited trait or characteristic. The development of genetic testing for these traits has resulted in a significant paradigm shift from historical breeding practices for the dog breeding community. With a few exceptions for colors or patterns that cannot yet be tested for, genetic coat color testing has eliminated the need to perform test breedings or to make assumptions when it comes to determining what coat colors and traits might be produced by a specific breeding pair.

Genetic Coat Color Testing Basics

Despite its power, the use of genetic testing does not eliminate the artistry of dog breeding or the advantages that come from experience. Instead, genetic testing assists in eliminating some of the challenges that biology presents. Regardless of a breeder’s experience level, colors or traits that are inherited in a recessive fashion can present significant challenges when it comes to predicting potential coat color breeding outcomes. Recessive traits are those that require a dog to inherit two copies of the associated genetic variant (one from each parent) in order to display that trait. The challenge with recessive traits is that dogs ...

Over the past two decades, usage of genetic testing technologies has revolutionized the world of dog breeding. Once limited to selective breeding practices based upon the characteristics or disease states that could be physically observed in a dog, genetic testing has allowed dog breeders to uncover the inherited genetic variants (mutations) that are not being expressed in an individual but may be expressed in their offspring. By comparing the disease-associated mutations inherited by a dog to those of a prospective mate, informed breeding decisions can be made to avoid producing puppies with these diseases. However, despite the immense value of genetic disease testing in the production of healthy puppies, incorrect assumptions about the parentage of a litter can have disastrous consequences for the health of a kennel, even when parental genetic disease testing results are 100% accurate.

Clear by Parentage/Hereditary Clear

In ideal situations, potential dams and sires are tested for breed-specific, disease-associated genetic mutations prior to being bred. If both parents are found to be free of these mutations (often referred to as being “clear”), it can be assumed for practical purposes that the offspring are also clear of the same mutations. With this understanding, it is common ...

Every veterinarian leaves veterinary school with a mental laundry list of animal diseases and their textbook presentations. While this knowledge serves the young graduate well in most circumstances, with clinical experience and mentorship comes the ability for veterinarians to expand their mental notes about the various ways some diseases can present in the real world. For some inherited canine diseases, genetic testing has allowed the practitioner to correlate a broader set of clinical signs for dogs affected by identical underlying genetic mutations. This variability in disease phenotype, known as variable expressivity, is a result of the combined effect of all genetic and environmental factors influencing each individual and can add significant challenge to some diagnoses. However, supplementing a disease workup with genetic test results can prove invaluable in diagnosing inherited diseases that have the frustrating attribute of rarely presenting the same way twice.

Collie Eye Anomaly

Now known to occur in well over a dozen breeds, the recessively inherited collie eye anomaly or CEA (also known as choroidal hypoplasia) is a relatively common eye disease of dogs and a good example of a disorder which can have diagnostic challenges due to its phenotypic variability. CEA is caused by a deletion ...

The discovery of various disease-associated genetic mutations has greatly changed the way some inherited canine diseases are categorized and perceived by the veterinary community. Through the use of genetic testing developed to identify these discovered mutations, various diseases which were once assumed to have a single underlying molecular cause (due to similarity between disease states) have been found in some cases to actually be caused by many different mutations, often in different genes. This phenomenon, known as genetic heterogeneity, elucidates the way genes work together in pathways and how a disruption in different genes of a pathway may result in similar or nearly identical disease states despite seemingly disparate underlying molecular etiologies. Understanding that there may be one of many different genetic mutations responsible for a dog’s clinical signs can help plot a better course for veterinarians to obtain an accurate, definitive diagnosis and in some cases, may alter treatment strategies.

Pet Owner vs Breeder

The accuracy and specificity of an inherited disease diagnosis are particularly important in the world of dog breeding where every potential health issue must be considered prior to breeding. Unlike general pet owners who may not need to know the specific underlying molecular mechanisms of ...

As a laboratory that works directly with breeders and dog owners, Paw Print Genetics (PPG) is often asked to reassure the customer that our tests accurately determine whether a dog will get a disease.  The customer is actually asking a couple of different questions; one involving the accuracy of the test itself and one regarding the clinical validity of the test. It is important to understand the questions being asked so that the answers make sense.

The first question being asked is: Does the test perform accurately to determine if a dog is normal/clear, a carrier of one copy of the mutation or at risk, having two copies of the mutation. At PPG, our tests are extensively validated and must show 99.9% specificity and sensitivity before being available for ordering. Sensitivity is defined as the proportion of samples with a known mutation that are correctly classified/identified as carrier or at risk by their genotypes. Specificity is defined as the proportion of samples with no known mutation that are correctly classified/identified with the wildtype (normal) genotype for the disease.  This all refers to whether the test result accurately reflects the true genotype of the individual. At ...

While advancements in science, medicine, and agriculture have played a role in decreasing the relative importance of the dog in human survival, their importance as pets, companions, and surrogate family members may be greater than ever. Once more commonly selected for their athletic prowess and behavioral traits, the rise of dog fancying over the past 250 years has elevated the importance of canine aesthetics to previously unprecedented heights. As a result, dog breeders have historically gone to great lengths to produce dogs with unique phenotypic characteristics desirable to potential pet buyers. While most of these characteristics are simple, mendelian genetic traits without health concerns, some desirable and interesting traits such as the merle coat color pattern are unique to domestic animals and bring with them a complexity and potential health concerns that veterinarians should be aware of in their goal of facilitating canine health and wellbeing. 

An Interesting Mutation for an Interesting Haircoat

In 2006, Dr. Leigh Anne Clark and others identified a semi-dominant genetic mutation responsible for the merle coat color pattern commonly seen in numerous dog breeds including the Australian shepherd, collie, border collie, and dachshund. Merle coat color is marked by areas of normal, eumelanistic pigmentation ...

As one year closes and we begin a new, I like to take this time to reflect on the accomplishments of Paw Print Genetics (PPG).  It still amazes me that in such a short time (PPG was founded in 2012), we have become the most trusted laboratory in the industry.  Even if we didn’t do the testing, breeders come to us for advice and help in figuring out the sometimes complex nature of genetic testing results.  Perhaps this is because we are so accessible. PPG employs PhD geneticists and licensed veterinarians who are on-staff and in our offices, available by phone for consultation about your breeding program, a particular dog that needs testing, or a specific result.  Providing genetic counseling and a helpful ear is so important for assisting breeders in navigating the ever-changing world of canine genetics.

As in previous years, PPG had many accomplishments this year. Only a few are highlighted in the following paragraphs. For me, our biggest accomplishment is how fast we continue to grow and the number of new breeders who tried us for the first time this past year.  These new customers are finding us mostly from you – our current ...

Our Paw Print Genetics (PPG) clients frequently share with us some of the great ideas they utilize to help in their quest to produce happy and healthy litters. Recently, one of our wonderful clients (for this blog, I will call her Carol) gave me an awesome tip regarding her method for drying out umbilical cords, docked tails, or dew claws that she intends to send to PPG as samples for DNA extraction and genetic testing.

Carol’s method involves pulling out her old trusty muffin tin and using the paper liners typically used for baking. Carol prepares one paper liner for each puppy by writing the specific puppy’s name (most commonly corresponding to the puppy’s collar color)  as well as the Paw Print Genetics ID number that is generated on the PPG website when a dog is added to an account.  She then places each liner into one of the metal cups in the muffin tin.

As her veterinarian collects each sample, Carol carefully deposits each sample into the labeled liner corresponding to the correct puppy. To prevent DNA contamination between puppies, she requests that the veterinarian clean the tools and change gloves before collecting the sample on the next pup ...

Discovery of disease-associated, canine genetic mutations has greatly increased over the past two decades. As a result, identification of these mutations through genetic testing has quickly become a useful tool for dog kennels and veterinary practices by allowing for the identification of asymptomatic disease carriers, diagnosis of affected dogs, and prevention of inherited diseases through informed breeding practices. However, because mutation discovery is often funded by specific breed clubs with interest in a breed-related disease concern, study investigators may not perform extensive, species-wide population studies for a newly discovered mutation. Therefore, in many cases, additional breeds inheriting the same mutation (and developing the same disease) may remain unknown for quite some time after the initial discovery.

As any modern veterinarian can attest, for better or worse, animal lovers have more veterinary medical information at their fingertips than ever before. Occasionally, at Paw Print Genetics, we are contacted by breeders or owners whose veterinarian had opted not to pursue a diagnosis that the client suspected because of the veterinarian’s historical understanding of a disease’s breed-specific distribution rather than the current knowledge. For veterinarians building a differential diagnosis list, keeping the mind open to a particular inherited disease manifesting in an unexpected ...

Paw Print Genetics is special and I am not just saying that because I am the CEO. There is no other canine genetics laboratory like PPG. Seriously!  Paw Print Genetics is the only laboratory that has implemented human-based testing standards. What does this mean?  It means that PPG tests each mutation region twice with two different methods to ensure the highest accuracy possible. No laboratory can boast 100% accuracy, but PPG achieves 99.9% accuracy each and every day. This means that you can trust your results and use them confidently in your breeding program. In addition, PPG employs both PhD Geneticists and licensed Veterinarians on staff, in our offices, that oversee the testing and report the results. You can also call and speak to them if you have any questions or concerns. Finally, I am the only board certified geneticist in the canine field; I am board certified by the American Board of Medical Genetics. These three aspects - the 'double check testing', having geneticists and veterinarians on staff, and having a board certified geneticist on staff - are equivalent to the requirements found in human genetic testing laboratories.

In addition to our high testing standards and customer access ...