Tag archives: blindness

Don’t Turn a Blind Eye to Inherited Disease - Preventing Blindness Through Genetic Testing

Don’t Turn a Blind Eye to Inherited Disease - Preventing Blindness Through Genetic Testing

Since we started working with the Boykin Spaniel Society (BSS), both Paw Print Genetics (PPG) and the BSS have learned much about the genetic disease concerns of these wonderful, little brown dogs. By using the founder breeds of the Boykin as a guide, PPG developed the first Boykin spaniel inherited disease testing panel in 2014. Based upon the results collected over two years of testing Boykins, in September 2016, the original disease testing panel was split into two panels; the Boykin spaniel essential panel (containing the most clinically important and/or common diseases) and the supplemental panel (containing diseases of less clinical importance and/or lower incidence).

Two of the four diseases on the Boykin spaniel essential panel are inherited diseases of the eye. Diseases resulting in vision loss or blindness are among some of the most life-altering and troublesome non-lethal diseases of dogs. However, with knowledge of a specific genetic mutation resulting in blindness as well as an understanding of how that specific eye disease is inherited, blindness caused by the mutation can be prevented through the use of genetic testing and informed selective breeding practices based upon test results. Two eye diseases known to be inherited in the ...

Prevention Is Smart Breeding- Progressive Retinal Atrophy and the American Eskimo Dog

Prevention Is Smart Breeding- Progressive Retinal Atrophy and the American Eskimo Dog

Despite its name, the roots of the American Eskimo dog can be traced back to Germany where it was known as a white colored, miniature to medium sized variety of the German spitz. This well rounded farm dog came to the United States with German immigrants in the early 20th century and adopted the name American spitz in the World War I era when war related anti-German sentiment and American patriotism were widespread. The breed was first recognized as the American Eskimo dog (AED) by the United Kennel Club in 1919 and was accepted by the American Kennel Club for registration in 1995. Known for its alert demeanor, the AED makes an excellent watchdog that alarms its family of potential danger through warning barks. The AEDs intelligence, fast learning, and desire to please have made it a competitor in the agility ring and obedience trials. Though not universally recognized as three separate varieties, the modern AED is often split into three size groups (toy, miniature, and standard).

Despite its many talents, beautiful physical characteristics, and intelligence, like other pure breeds, the AED has developed some inherited disease concerns over the course of its development that have caused significant issues ...

Prevention Is Smart Breeding- Collie Eye Anomaly and the Australian Shepherd

Prevention Is Smart Breeding- Collie Eye Anomaly and the Australian Shepherd

Despite a name which implies an origin “down under”, the Australian shepherd is widely understood to be a breed of American origin. In fact, descriptions of the breed and their importance in the lives of 19th and 20th century Basque shepherds who had relocated from Australia to the western US are plentiful. Australian shepherds’ exceptional intelligence, versatility, desire to please, and a natural instinct to herd and guard livestock have made them a common inhabitant of ranches and farms where they have been trained to perform a variety of tasks. Aside from their work on the homestead, their unique abilities have also made them great competitors in stock dog trials, agility events, and other dog sports. Despite their many talents and desirable traits, like many other breeds, the Australian shepherd has developed some inherited disease concerns that can prevent them from performing at their best or otherwise decrease their overall quality of life. One such condition recognized in the Australian shepherd is the genetic eye disease known as collie eye anomaly.

What is CEA?

Collie eye anomaly (CEA), also known as choroidal hypoplasia, is an inherited eye disease caused by a mutation in the canine NHEJ1 gene. Dogs ...

Preventing Inherited Progressive Retinal Atrophy in the Irish Setter

Preventing Inherited Progressive Retinal Atrophy in the Irish Setter

Despite its once prominent role as a talented upland gamebird hunting dog, by the mid-1900s the Irish Setter’s popularity in the field was on the decline. Despite developing significant interest and success as a show dog, the breed had nearly disappeared from the hip of gamebird hunters. Around this time, outbreedings to field champion English setters were performed in an effort to resurrect the popularity and improve the talents of the Irish setter as a hunting companion. In many locales, this field bred variety of Irish setter became known as the red setter while the Irish setter name is now most closely associated with the show variety of the breed. In the United States however, red setters still fall under the umbrella of the Irish setter name. Found in multiple colors and coat patterns in its early history, the breed’s modern solid red coat color became entrenched in the breed due to its popularity in the European show ring of the late 1800s.

Like other purebred dogs, the Irish setter has developed some inherited disease concerns along its path to its modern state. However, through the use of modern genetic testing technology and selective breeding practices, some inherited diseases can now be ...

Preventing Inherited Progressive Retinal Atrophy in Poodles

Preventing Inherited Progressive Retinal Atrophy in Poodles

Despite their characterization in popular culture as a gorgeous, yet delicate dog breed with more beauty than brawn, the ancestors of today’s poodles (especially standard poodles) were revered for their ability to work. Still well known for their exceptional intelligence, the standard poodle (the oldest poodle variety), was commonly used as a gun dog and water retriever to assist European hunters. Portrayed in drawings and paintings from as early as the 15th century, the standard poodle was eventually bred to smaller breeds in order to create poodles of smaller size. The resulting smaller dogs, which reportedly disliked water, were used for truffle hunting and formed the ancestry of today’s toy and miniature poodle breeds. Though no longer commonly thought of as gun dogs, interest in using standard poodles as hunting dogs has reemerged with some standard poodles experiencing success in AKC and CKC hunting trials since the mid to late 1990’s. Toy and miniature poodles are most commonly recognized today as family-friendly companion dogs. During their path of development, like other purebred dogs, all three commonly recognized varieties of poodles have developed some inherited diseases that can make life challenging. One particular disease of poodles known as progressive retinal ...

Preventing Inherited Ataxias and Primary Lens Luxation in the Parson Russell Terrier and Related Breeds

Preventing Inherited Ataxias and Primary Lens Luxation in the Parson Russell Terrier and Related Breeds

Previously known as the Jack Russell terrier, the Parson Russell terrier’s nearly 200 year long history began in the 1800’s when Parson John Russell of England obtained a terrier named Scout with the purpose of training him for European red fox hunting. Russell eventually developed a particularly adept line of terriers meant to run alongside hunters on horseback and dispatch foxes.

The name, Jack Russell Terrier was previously used to encompass dogs which are now recognized as three separate breeds in the U.S, the Jack Russell terrier, the Parson Russell terrier, and the Russell terrier. Despite their close genetic relationship and very similar appearance, leg length and body shape can be used to help differentiate the three breeds. Parson Russell terriers possess the longest legs and a square-shaped body while the other two breeds display shorter legs and a rectangular body shape. The Russell terrier is the shortest of the three varieties. Parson Russell terriers and Russell terriers are both recognized by the AKC, however the Jack Russell Terrier remains unrecognized by the organization and is bred primarily for its ability to hunt rather than for its conformational merits. Despite these physical differences, the three breeds share many genetic similarities ...

Preventing Hereditary Cataracts in the French Bulldog

Preventing Hereditary Cataracts in the French Bulldog

Though there are mysteries in regards to the early origins of the French bulldog, it is probable that this spunky breed is a 19th century product of breeding early English bulldogs and miniature bulldogs with other small breeds. As these smaller, English bred bulldogs became popular, many were either exported to France from England or accompanied their English owners to France in search of employment. At some point in the mid to late 1800’s, the small bulldogs were given the name “Bouledogue Français” and were recognized as their own unique breed. Early French bulldogs with either “rose ears” (ears folded at the tip) or pricked “bat ears” were common. However, with the spread of the breed to the United States, American dog fanciers created the first French bulldog breed standard describing the “bat ear” trait seen in modern Frenchies as the “correct” ear type.  In the process of establishing their modern appearance and perfecting the breed, like other purebred dogs, French bulldogs have developed some inherited diseases that concern Frenchie aficionados today. One such disease is a disorder known as hereditary cataracts (HC).

A cataract, in general, is the clouding of the lens of the eye. This cloudiness interferes ...

Cystinuria and Progressive Retinal Atrophy, Progressive Rod-Cone Degeneration in the Labrador Retriever

Cystinuria and Progressive Retinal Atrophy, Progressive Rod-Cone Degeneration in the Labrador Retriever

In this fourth and final blog in a series about preventable inherited diseases in the Labrador retriever (see previous blogs here; part one, part two, and part three), we will examine a potentially life-threating urinary disease and a cause of blindness in dozens of dog breeds including the Labrador.

Cystinuria

Urinary tract obstruction is one of the most urgent and potentially life-threatening conditions in dogs. One common cause of urinary obstructions in dogs is the presence of bladder stones which leave the bladder during urination and become lodged in the urethra. The inability to urinate results in a toxic buildup of certain electrolytes and waste products in the body including potassium, which tends to be the most concerning in regards to health effects. Excess potassium in the body prevents the heart from beating normally, ultimately resulting in death due to cardiac arrest. Though it is not the only cause of bladder stones in Labradors, a genetic mutation in the SLC3A1 gene is reported to cause an early-onset disease known as cystinuria, which can result in bladder stone formation.

While normal kidneys reabsorb a variety of nutrients and electrolytes from the urine, dogs affected with cystinuria lack the ability to produce ...

Skeletal Dysplasia 2 and Retinal Dysplasia/Oculoskeletal Dysplasia 1 in the Labrador retriever

Skeletal Dysplasia 2 and Retinal Dysplasia/Oculoskeletal Dysplasia 1 in the Labrador retriever

In this second part of a four part blog series examining preventable inherited diseases of the Labrador retriever (see part one here) we will be examining two diseases known to cause dwarfism in the breed.

Skeletal Dysplasia 2

Skeletal dysplasia 2 (SD2) is an inherited disease of collagen resulting in disproportionate dwarfism in the Labrador. Disproportionate dwarfism is marked by abnormal size discrepancies between the limb length of affected individuals and the size of their torso. In the case of SD2, the limbs of affected dogs tend to be shorter than normal despite an average sized torso. International breed standards of the Labrador list shoulder heights of 56-57 cm in males and 54-56 cm in females. In the publication describing the COL11A2 gene mutation associated with SD2, the authors found that most of the affected males had shoulder heights of less than 55 cm and most affected females showed heights of less than 50 cm. However, there is some overlap of shoulder heights between those of normal dogs from blood lines of smaller size and affected dogs from larger sized blood lines. Though the front limbs tend to be more severely affected (and sometimes slightly bowed) with SD2, the long ...

Retinal Dysplasia/Oculoskeletal Dysplasia 1 (RD/OSD1): A Preventable Inherited Disease of the Labrador Retriever

Retinal Dysplasia/Oculoskeletal Dysplasia 1 (RD/OSD1): A Preventable Inherited Disease of the Labrador Retriever

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 ...