Tag archives: dog dna test

Paw Print Genetics Adds New Canine Genetic Disease Tests to Ever-Expanding Offerings

Paw Print Genetics Adds New Canine Genetic Disease Tests to Ever-Expanding Offerings

With the current, rapid pace of new genetic discoveries, inherited disease testing is quickly becoming a common part of clinical veterinary diagnostics. Paw Print Genetics is excited to announce the release of six new canine genetic disease tests, including highly anticipated tests for three diseases in retriever breeds; macular corneal dystrophy and congenital myasthenic syndrome in the Labrador retriever and neuronal ceroid lipofuscinosis 5 in the golden retriever.

Macular Corneal Dystrophy

With an estimated mutation carrier rate of 3.3% in a 2015 study of the UK Labrador retrievers, macular corneal dystrophy (MCD) is an inherited eye disease that that is likely to be encountered at some point in a small animal veterinarian’s career1.

Inherited in a recessive manner, Labradors with two copies of the associated CHST6 gene mutation typically present in middle age with MCD-associated vision loss. Affected dogs display decreased activity of an enzyme known as corneal glucosamine N-acetyl-6-sulfotransferase (C-GlcNAc6ST), which results in decreased sulfation of the corneal glycosaminoglycan, keratin sulfate (KS). Decreased sulfation of KS reduces its solubility, thus preventing its full metabolism and allowing for deposition into the extracellular space of the corneal stroma and Desmet’s membrane, and intracellularly in keratinocytes and corneal epithelial cells ...

For The Veterinarian: The Genetics of Shortened Limbs and the Association with Canine Intervertebral Disc Disease (IVDD)

For The Veterinarian: The Genetics of Shortened Limbs and the Association with Canine Intervertebral Disc Disease (IVDD)

Shortened legs are a major defining feature for some of today’s most popular domestic dog breeds. Although dogs with extreme shortening of the limbs likely come to mind when pondering this trait (such as dachshunds or basset hounds), many other breeds also display a more subtle or moderate limb shortening (e.g. West Highland white terrier, Nova Scotia duck tolling retriever, beagle). Unfortunately, in some breeds, dogs with shortened legs have also been found to be at an increased risk for early-onset intervertebral disc disease (IVDD). However, over the past several years, genetic discoveries and development of genetic testing have made it possible to better understand the short-legged appearance of some dog breeds and the genetic underpinnings which make some of these dogs more likely to develop IVDD.

Shortened Legs and Genetic Link to Intervertebral Disc Disease

Two genetic mutations associated with shorter limb length have been reported in domestic dogs2,4,5. Both mutations consist of a duplicated section of the canine FGF4 gene (called an FGF4-retrogene) which has been inserted into two aberrant locations of the genome; one copy has been inserted into a region on chromosome 12 (CFA12 FGF4 insertion) and the other copy has ...

The Genetics of Shortened Limbs and the Association with Canine Intervertebral Disc Disease (IVDD)

The Genetics of Shortened Limbs and the Association with Canine Intervertebral Disc Disease (IVDD)

Shortened legs are a major defining feature for some of today’s most popular domestic dog breeds. Although dogs with extreme shortening of the limbs likely come to mind when pondering this trait (such as dachshunds or basset hounds), many other breeds also display a more subtle or moderate limb shortening (e.g. West Highland white terrier, Nova Scotia duck tolling retriever, beagle). Unfortunately, in some breeds, dogs with shortened legs have also been found to be at an increased risk for early-onset intervertebral disc disease (IVDD). However, over the past several years, genetic discoveries and development of genetic testing have made it possible to better understand the short-legged appearance of some dog breeds and the genetic underpinnings which make some of these dogs more likely to develop IVDD.

Intervertebral Discs and the Spinal Cord

In order to understand IVDD, we must first understand the role, location, and structure of the intervertebral discs (IVDs) and their anatomical relationship to the spinal cord. IVDs play a crucial role as cartilaginous ‘shock absorbers’ for the spine and allow for spinal flexibility. IVDs are often compared to a ‘jelly doughnut’ sitting between the vertebrae as they are composed of an outer ring of tough ...

Genetic Health Screening, the Canine HealthCheck, and Benefits for Veterinary Practice

Genetic Health Screening, the Canine HealthCheck, and Benefits for Veterinary Practice

The impact of canine genetic testing on veterinary medicine continues to grow as dog owners become increasingly interested in the genetic factors underlying their dogs’ health and how knowledge of these factors may improve the lives of their furry companions. Genetic screening tools which test for large numbers of deleterious genetic mutations, such as the Canine HealthCheck (CHC) developed by Paw Print Genetics (PPG), are particularly useful when performed on a young dog to identify specific inherited health concerns; especially in cases where the lineage of the dog is unknown.

Early Screening, Faster Diagnosis

Among the tests performed on the CHC are disease tests which may prove invaluable in decreasing client costs associated with diagnosis, increasing speed of diagnosis, or improving medical outcomes. For example, many tests included on the CHC, such as the test for the neurological disease, degenerative myelopathy (DM) are adult-onset conditions which may not be observed in a dog until it has reached late adulthood. DM is a progressive disease caused by a genetic mutation in the canine SOD1 gene which can only be definitively diagnosed after death through histologic examination of the spinal cord because antemortem diagnostic methods fail to yield pathognomonic results. In addition ...

Merging Science and Art: Using Genetic Testing to Produce the Seven Standard Great Dane Coat Colors and Patterns

Merging Science and Art: Using Genetic Testing to Produce the Seven Standard Great Dane Coat Colors and Patterns

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 ...

The Veterinarian's Corner: Incorrectly Recorded Canine Parentage and the Effect on Genetic Health

The Veterinarian's Corner: Incorrectly Recorded Canine Parentage and the Effect on Genetic Health

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 ...

The Veterinarian’s Corner: Variable Disease Presentation and How Genetic Testing Can Help

The Veterinarian’s Corner: Variable Disease Presentation and How Genetic Testing Can Help

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 Veterinarian’s Corner: Genetic Heterogeneity and Its Importance in Dog Breeding

The Veterinarian’s Corner: Genetic Heterogeneity and Its Importance in Dog Breeding

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 ...

Merle Coat Color- What Veterinarians Should Know

Merle Coat Color- What Veterinarians Should Know

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 ...

Canine Genetic Disease Testing Prior to Other Health Clearances- Why It Makes Sense

Canine Genetic Disease Testing Prior to Other Health Clearances- Why It Makes Sense

Once only a dream for dog lovers, technological advances in the sciences have now made testing for certain inherited diseases a mainstay of modern dog breeding. With knowledge of specific, disease-associated genetic mutations and an understanding of how these diseases are inherited, tests can be developed to identify dams and sires at risk of producing affected puppies. With this knowledge, informed decisions can be made in selecting mates which can safely be bred together.

As the Associate Medical Director at Paw Print Genetics, I have heard many different strategies employed by our clients to get required or recommended health clearances performed on their dogs prior to breeding. Some choose to break up the testing over time to spread out the cost and many choose one type of health clearance to be performed first with other testing to be completed upon the results of the first round of testing. For a variety of reasons, I propose that performing genetic testing on breeding dogs prior to other health clearances is a practical option that may be in the best interest for many breeders.

Test at Any Age

One advantage to performing genetic health testing prior to other clearances is that genetic testing ...