Category archives: Ask The Vet

In 1953, a prevalent inherited eye condition of collies was first described by W.G. Magrane in a journal article entitled, “Congenital anomaly of the optic nerve in collies”¹. Later termed choroidal hypoplasia by scientists, the disease now known to the general public as collie eye anomaly (CEA) has significantly troubled collie breeders for over 50 years. In 2007, a paper describing a specific genetic mutation of the NHEJ1 gene associated with CEA was published. Identification of this mutation, has made it possible for scientists to develop tests that predictably identify the mutation and subsequently help breeders avoid producing puppies with CEA. Despite its breed specific name, testing has since identified the same CEA associated mutation in several other dog breeds including the Australian shepherd and the Shetland sheepdog.

Though there is significant variability in terms of ocular defects seen in affected dogs, the fundamental characteristics of CEA stem from the malformation of an important structure of the eye known as the choroid. The choroid is a thin layer of tissue containing the blood vessels responsible for supplying blood and nutrients to the retina and other structures of the eye. While mildly affected dogs may maintain normal vision with ...

From their origins in Germany, the miniature schnauzer and its entertaining, high-spirited personality have endeared them to people all over the world. Originally bred to be an effective, small breed vermin hunter, it is believed that the miniature schnauzer was the product of breeding small breeds like the affenpincher and small poodles with the standard schnauzer. First recognized as an independent breed in the late 19^th century, miniature schnauzers have since firmly planted themselves as popular, devoted family members and guard dogs. In 2013, they were ranked 17th in the AKC registration statistics; an indication of their significant popularity in the US. Unfortunately, like other purebred dogs, the miniature schnauzer is reported to inherit some genetic diseases that can prevent them from being the spunky terrier they are otherwise known to be. One such condition is an inherited muscular disease known as myotonia congenita (MC).

MC is a disorder of skeletal muscle caused by a mutation of the CLCN1 gene in which muscles display hyperexcitability and delayed relaxation after contracting. Affected puppies are usually identified when they begin walking due to the presence of a stiff gait resulting in frequent falls. Though the episodes of muscle stiffness do not ...

Throughout human history, people have learned to use a variety of animals to help perform essential tasks in an attempt to make their lives easier. While dogs are often recognized for their skill as hunters or as integral hunting companions in pursuit of a variety of game, one under recognized skill of dogs is as draft animals. While we often associate draft or sled dogs with competitive racing such as the Iditarod or Yukon Quest races, many do not realize that these races were developed from the historical use of dogs as draft animals. One dog breed with significant roots as both a hunting and draft animal is the Alaskan malamute.

Early accounts describe ancestors of the Alaskan malamute being used by the native Alaskan tribe previously known as Mahlemuts. These dogs played a crucial role in helping the tribe succeed in the harsh and unforgiving land of northwestern Alaska by assisting them with hunting and pulling sleds. When gold fever struck the Yukon and Alaska in the 19^th century, demand for malamutes and other capable draft dogs increased substantially to assist hopeful prospectors in their quest for a golden fortune. Often confused with the Siberian husky due to ...

Thanks to our loyal and dedicated clients, Paw Print Genetics continues to increase test offerings in 2015! To start our year off right, we released DNA profiling and parentage testing, seven long-awaited canine coat color tests, and four tests for other specific traits of the hair coat and tail. In addition, Paw Print Genetics continues to expand upon the largest canine inherited disease testing menu in North America by releasing 10 new inherited disease tests. One newly added test that will make many Labrador retriever owners happy is the test for an inherited disease known as retinal dysplasia or the more apt term, oculoskeletal dysplasia (often written as retinal dysplasia/oculoskeletal dysplasia 1 or abbreviated, RD/OSD 1). In March of 2014, RD/OSD 1 became a little more personal for Paw Print Genetics when we had the honor of meeting Frank, an adorable, blind RD/OSD 1 affected Labrador retriever living at the Double J Dog ranch in Hauser Lake, Idaho. We are excited to launch a test that allows breeders of sweet dogs like Frank to produce puppies free of this severe and challenging disorder!

RD/OSD 1 is a genetic disease of collagen caused by a mutation ...

Selective breeding for particular behavioral and physical characteristics has made the domestic dog one of the most fascinating case studies in species domestication. The massive amount of diversity that humans have bred into their canine companions is unmatched by other species, domestic or otherwise. It is fun to imagine how unusual it would seem if humans were routinely as physically diverse as Chihuahuas and mastiffs!

One trait that has been selected for in some dog breeds is a trait known as “furnishings”. For the uninformed, furnishings are a trait marked by a wiry hair texture as well as increased hair growth on the face and legs. This trait is important to some breeders as it is associated with the presence of a canine moustache and long eyebrows which are listed as breed standards for some breeds. Dogs of these breeds that are born without furnishings are often said to have been born with an “improper coat” (a term frequently used by breeders). In 2010, a mutation in the RSPO2 gene was discovered to be responsible for the presence of furnishings in the Portuguese water dog. Since then, tests for this trait have been developed allowing for discovery of the same ...

There are not many dog breed names that give a more apt description of the breed’s physical appearance than that of the coton de Tulear. Taken from the French word “coton”, meaning cotton, the coton de Tulear’s signature soft white hair (not fur) has long been compared to the fluffy fiber of the cotton plant. According to the Malagasy Coton de Tulear Club of America, the coton de Tulear was developed in Madagascar around the 17^th century and is still the official dog of this island nation. Predecessors to the modern coton de Tulear were likely brought to the island by sailors or pirates around this time period. Though they are generally a healthy breed, unfortunately, like other purebred dogs, the coton de Tulear is known to inherit some genetic diseases that can make life challenging for this small, friendly companion and those that love them. One such inherited disease of the coton de Tulear is a severe condition known as primary hyperoxaluria (PH) that occurs due to a mutation in the AGXT gene.

Dogs affected with PH lack the ability to produce an enzyme that plays an essential role in the breakdown of a compound known as glyoxylate ...

After many inquiries by our wonderful clients, Paw Print Genetics is excited to announce that we have begun testing for two genetic mutations reported to cause progressive retinal atrophy in the golden retriever. Known specifically as progressive retinal atrophy, GR1 and GR2 (PRA-GR1 and PRA-GR2), these two diseases were found to be caused by genetic mutations in the SLC4A3 and TTC8 genes, respectively. In addition to the golden retriever, the TTC8 mutation that causes PRA-GR2 has also been identified in a clinically affected Labrador retriever.

Progressive retinal atrophy (PRA) is not a single disease, but rather a group of inherited diseases each caused by different genetic mutations in different genes. The various forms of PRA affect over 100 different dog breeds. Though there are variations in the progression of disease, most varieties of PRA (regardless of genetic cause) result in blindness due to an inherited degeneration of the retina; more specifically, the degeneration of retinal cells known as rods and cones, which play an important role in vision.

In PRA-GR1 and PRA-GR2, signs of night blindness and loss of peripheral vision are seen first with progression to complete blindness occurring over time. In addition, they are both considered late onset ...

One of the hottest questions from our loyal, Paw Print Genetics clients over the past several months has been, “When are you going to offer genetic testing for hereditary cataracts?” After much preparation and anticipation, we are happy to report that Paw Print Genetics has begun testing for two different mutations of the HSF4 gene reported to cause hereditary cataracts (HC) in seven different breeds of dog.

Cataract is the term used to describe a condition in which opacities develop in the normally clear lens of the eye. The lens is responsible for focusing light onto the retina in the back of the eye resulting in acute, focused vision. With cataracts, the lens cannot focus light appropriately. This results in progressive vision deficits as the cataract increases in severity. While many cataracts identified in dogs are caused by non-inherited causes (e.g. UV radiation, infections, diabetes, chronic inflammation of the eye), as the name suggests, HCs are those passed from generation to generation. In addition, inherited genetic mutations are the most common cause of cataracts in dogs. However, by performing genetic testing on dams and sires prior to breeding, selective breeding precautions can be taken to prevent affected puppies ...

With their picturesque appeal, predecessors of the modern day papillon (known as continental toy or Titian spaniels) were popular subjects for European painters between the 16^th and 18^th centuries. The popularity of these small spaniels with European aristocrats and royalty of the Renaissance period, led to their appearance in many paintings from the era. The iconic, longhaired “butterfly-like” ears, for which papillons are named, are obvious in these paintings though many of the portrayed dogs were of the drop-eared variety of the breed that today is known as the phalène. According to an article on the Papillon Club of America website, in the late 19^th century erect ears became a more desirable trait with papillon fanciers and eventually the erect-eared variety obtained their current position as the more popular form of the breed. In addition to their beautiful physical attributes, in their modern form, well-socialized papillons are described as happy, playful and affectionate family members. Papillons are also often described as frequent barkers, making them great guard dogs. Despite their adorable personalities and good temperament, like other purebred dogs, the papillon is known to inherit some genetic diseases that could prevent this regal breed from reaching the ...

From a thorough mixture of spaniels, pointers, and other setter breeds, the Irish setter made its rise to popular gun dog status in the 18^th century in its native homeland, Ireland. Though originally of the red and white color pattern (now called the Irish red and white setter), by the time the Irish setter made its way to North America, the solid red color most commonly associated with the breed had been established through selective breeding practices. Originally bred for their versatility in hunting game birds, by the mid 1900’s the Irish setter’s role in the field had greatly diminished despite their popularity in the show ring. Controversial, yet successful, efforts were taken to outcross the breed to red and white champion English setters in order to preserve and improve field varieties. The resultant field variety, often referred to as the Red setter, is unique in its hunting abilities and appearance when compared to American show varieties of the Irish setter. However, the field variety still falls under the Irish setter name in the US.

Unfortunately, at some point during the breed’s development, a spontaneous mutation in the ITGB2 gene occurred in a single Irish setter. A portion of ...