Tag archives: neurological disease

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 ...

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 dogs^2,4,5. 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 ...

As part of our commitment to raising the standard in canine genetic disease testing, the team at Paw Print Genetics works hard to assess the validity of genetic mutations published in the medical literature and to develop new disease tests based upon this information. The most recent test to be added to our extensive disease testing menu is for a disease known to be inherited in golden retrievers called   neuronal ceroid lipofuscinosis 5.

What is neuronal ceroid lipofuscinosis 5?

Neuronal ceroid lipofuscinosis (NCL) is an inherited neurological disease belonging to a group of diseases called lysosomal storage diseases. There are multiple types of NCL, each given a number designation based upon the specific gene in which the associated genetic mutation is found. For example, dogs diagnosed with neuronal ceroid lipofuscinosis 5 (NCL5) have inherited a genetic mutation in the canine CLN5 gene. Although there are multiple dog breeds known to inherit NCL5 due to mutations in this gene, the specific mutation responsible for this disease in golden retrievers has only been found in this breed; thus, making testing for NCL5 in golden retrievers breed-specific.

What do the symptoms include?

Dogs affected with NCL5 are born with a deficiency of a ...

With a personality much bigger than their diminutive size, the toy fox terrier (TFT) is a fun and feisty breed well known for their charming and entertaining personalities. Originally created by the breeding of various toy breeds to the smooth fox terrier, like other terriers, TFTs still love the thrill of the hunt and are at their happiest giving chase to any small mammal willing to run. Though toy fox terriers have occasionally been described as headstrong and have been known to take control of a house, a well socialized and well trained toy fox terrier is a wonderful addition to many families. Still retaining tenacity from their terrier roots, their disposition is also tailored by the variety of toy breeds used to make this fine breed. Unfortunately, like other purebred dogs, the TFT has developed some inherited disease concerns along their path to the modern breed. Luckily, some of these diseases can now be prevented by performing genetic testing on dams and sires prior to breeding and by implementing selective breeding strategies based upon these results. One such genetic condition known to occur in TFTs is congenital hypothyroidism with goiter (CHG), a disease caused by a genetic mutation in ...

The adorable Yorkshire terrier has become an important fixture in American households since its introduction to the United States in the late 19^th century. Originally bred in Scotland and going by the name “Scotch terrier”, the Yorkshire terrier was given its modern name after great improvements in the breed were made in the county of Yorkshire in northern England.

Like most dog breeds, the Yorkie has developed some inherited diseases on its path to the modern breed. The genetic mutations responsible for some better known, inherited diseases of Yorkies such as primary lens luxation (PLL) and a form of progressive retinal atrophy known as progressive rod-cone degeneration (PRA-prcd) have been identified. The identification of these mutations has made it possible for Yorkie breeders to test their dams and sires prior to breeding and to use informed selective breeding practices to prevent the birth of puppies with these conditions. While most Yorkie breeders are familiar with PLL and PRA-prcd in the breed, another inherited condition known as degenerative myelopathy (DM) is less well known by Yorkie breeders. However, DM may be a concern worth investigating further in the Yorkie as the associated mutation has been identified in the breed.

What ...

If there is anything that I have learned in Paw Print Genetics’ quest to prevent canine inherited diseases, it is that degenerative myelopathy (DM) is one of the most misunderstood diseases in the dog breeding community. This late-onset, progressive neurological disease is notorious for cutting affected dog’s lives short and preventing them from living out their golden years. Unfortunately, sometimes there are misunderstandings in regard to what causes DM, what DM genetic test results mean, and whether or not DM occurs in certain breeds or bloodlines. I will attempt to address the confusing aspects of DM in order to empower people to eliminate this devastating disease from their blood lines.

How Do DM Affected Dogs Present? How is it Inherited?

Dogs affected with DM typically begin showing signs of painless, hind limb weakness and loss of balance around 7 to 10 years of age. These dogs often have difficulty rising after lying down, will drag their hind feet while walking, and abnormally cross their legs while standing. As the disease progresses, affected dogs’ front limbs also become progressively weaker until the dog becomes unable to walk. Affected dogs also may develop urinary and fecal incontinence as the disease progresses. Most ...

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 ...