Igenity Canine Wellness

03 Doctor’s Message 05 Genomics 101 07 Conditions Bleeding Disorders Exercise-induced Collapse Intervertebral Disc Disease Lens Luxation Urate Crystals and Bladder Stones Mammary Tumors Pancreatitis Social Behavior

Doctor’s Message Dogs can tell you everything about their health.

Igenity® Canine Wellness is a DNA test that identifies genetic traits in dogs and gives you information that will help anticipate health issues and offer individualized preventive care. It’s much more than an ounce of prevention — it’s a lifetime of improved health.

The process is simple. A cheek swab is taken during examination and sent to the NEOGEN® Genomics lab. Our team will provide results, along with pet owner education tools to support your relationships with pet parents. We also provide online resources that will help your practice comfortably navigate the world of canine genomics, and how to use this technology to its full potential.

The key areas Igenity will reveal include nutrition insights, cancer risks, predisposition to several hereditary diseases, and genetic influences on dogs’ behavior.

Genomics is an important part of a pet’s medical history and will allow veterinary staff and pet parents to work together to provide the best care possible. Igenity Canine Wellness may reveal genetic risks that can be mitigated by: • • • • •

Taking special precautions prior to surgery for dogs at risk for clotting disorders Recommendations for exercise and lifestyle adjustments Diet and healthy body weight suggestions What conditions to be on the lookout for as the pet ages Special behavior predispositions to keep in mind for training and helping your pet and family live the best life possible

Igenity Canine Wellness Finding a healthy future.

© NEOGEN Corporation, 2021. NEOGEN and Igenity are registered trademarks of NEOGEN Corporation, Lansing, MI 48912 U.S.

Genomics 101 Genetics vs. Genomics

Genetics is the study of inherited genes and traits. Genomics is the study of an organism’s complete set of genetic information and how those genes behave and interact with each other.

DNA

Deoxyribonucleic acid (DNA) contains the genetic code, or sequence of an individual. While the majority of DNA in each dog is the same (that’s what makes a dog a dog), there are variations in the DNA which result in each individual’s unique physical characteristics. These variations in base pairs are called single nucleotide polymorphisms (SNPs). Igenity® Canine Wellness results are based on these variations in the DNA.

Genes

In dogs there are 38 pairs of chromosomes in addition to the X and Y sex chromosomes. Each chromosome is made up of many genes, blocks of DNA sequence that code for a specific protein. Proteins have a wide range of functions in the body including structure, function, and regulation of all of the body’s tissues and organs. Proteins dictate the observable physical or clinical characteristics of a dog, this is the phenotype.

Inheritance

Genes are units of heredity that are passed from a parent to offspring. Different versions of those genes, called alleles, influence the characteristics of the offspring. A genotype refers to which two copies of that allele the offspring inherited from each parent.

The effect of those alleles is dependent on the mode of inheritance. Many genetic traits known in dogs are autosomal recessive, animals that carry the trait will not show clinical signs, but can pass a risk variant to their offspring. The alternative is traits that are autosomal dominant; animals that have just one risk variant may show clinical signs. There could be exceptions to these rules of inheritance, examples include incomplete dominance, age-dependency and epistasis.

Simple vs. Complex Traits

Simple traits are monogenic traits meaning that the outcome is due to a single gene and can be tracked from one generation to the next based on mode of inheritance, dominant or recessive. Clinical outcome can sometimes be affected by additional factors: • Incomplete penetrance — not all affected animals will have the clinical outcome • Epistasis — the trait is affected by additional genetic factors • Age dependency — clinical manifestation of disease may not occur until later in life Complex traits are often due to many genetic factors as well as environmental factors. These traits do not always follow the traditional modes of inheritance from one generation to the next. One example of a complex trait on the Igenity Canine Wellness test is hypersociability, a behavioral predisposition.

Genetics is Only Part of the Story

The results of an Igenity Canine Wellness test can determine the heritable risk of cancer and underlying hereditary conditions.

Ultimately, important health and wellness predictors are revealed to guide the vet and client toward an approach to care that will uniquely benefit the patient.

© NEOGEN Corporation, 2021. NEOGEN and Igenity are registered trademarks of NEOGEN Corporation, Lansing, MI 48912 U.S.

Conditions What Conditions Does Igenity Canine Wellness Detect?

Some clinical conditions are mostly dependent on a single genetic variant (simple) while others are influenced by many different genetic factors (complex). Other factors such as age, breed, and genetic variability can also influence risk.

Level of Risk Associated with Variants Tested

Known Affected Breeds

Factor VII Deficiency

Beagles, English Bulldogs, Alaskan Malamutes, Alaskan Klee Kai, Miniature Schnauzers, Boxers, mixed breed

von Willebrand Disease Type I

Australian Terrier, Bernese Mountain Dog, Coton de Tulear, Doberman Pinscher, German Pinscher, Kerry Blue Terrier, Manchester Terrier, Papillon, Pembroke Welsh Corgi, Miniature Poodle, Standard Poodle, Toy Poodle, Red Setter, White Setter, Stabyhound, West Highland White Terrier

von Willebrand Disease Type II

German Shorthaired Pointer, German Wirehaired Pointer, Collie

Exercise-induced Collapse

Labrador Retrievers, Curly Coated Retrievers, Chesapeake Bay Retrievers, Boykin Spaniels, German Wire-haired Pointers, Old English Sheepdog, Cocker Spaniels, Pembroke Welsh Corgis

Urate Urinary Crystals & Stones

American Pit Bull Terrier, American Staffordshire Terrier, Australian Shepherd, Black Russian Terrier, Boerboel, Bulldog, Catahoula Leopard Dog, Dalmatian, German Shepherd, Giant Schnauzer, Jack Russell Terrier, Labrador Retriever, Lagotto Romagnolo, Large Munsterlander, Parson Russell Terrier, Pitbull, Pomeranian, Russell Terrier, Small Munsterlander, Swedish Vallhund, Vizsla, Weimaraner

Lens Luxation

American Eskimo Dog, American Hairless (Rat) Terrier, Australian Cattle Dog, Border Collie, Chinese Crested, Jack Russell Terrier, Jagd Terrier, Lakeland Terrier, Lancashire Heeler, Lucas Terrier, Miniature Bull Terrier, Norfolk Terrier, Norwich Terrier, Parson Russell Terrier, Patterdale Terrier, Rat Terrier, Russell Terrier, Sealyham Terrier, Teddy Roosevelt Terrier, Tenterfield Terrier, Tibetan Terrier, Toy Fox Terrier, Volpino Italiano, Welsh Terrier, Wire Fox Terrier, Yorkshire Terrier

Mammary Tumors

English Springer Spaniel Miniature Schnauzer

Pancreatitis Intervertebral Disc Disease (IVDD) Social Behavior

Beagle, Cocker Spaniel, Dachshund, French Bulldog, Lhasa Apso, Pekingese, Pembroke Welsh Corgi, Shih Tzu Many

Level of Risk Associated with Variants Tested: Environment and additional unknown genetic factors contribute to risk for these conditions. Genetic risk may not yet be well studied across breeds.

Genetic variant results in a specific alteration to a protein, but the clinical outcome (actual diagnosis/manifestation) is variable.

Clinical condition is highly associated with a single genetic variant. Patients at risk are likely to show clinical symptoms.

Š NEOGEN Corporation, 2021. NEOGEN and Igenity are registered trademarks of NEOGEN Corporation, Lansing, MI 48912 U.S.

01 Conditions

Bleeding Disorders

Factor VII Deficiency Reference

Callan MB, Aljamali MN, Margaritis P, Griot-Wenk ME, Pollak ES, Werner P, Giger U, High KA. A novel missense mutation responsible for factor VII deficiency in research Beagle colonies. J Thromb Haemost. 2006 Dec;4(12):2616-22. doi: 10.1111/j.1538-7836.2006.02203.x. Epub 2006 Sep 8. PMID: 16961583.

Abstract

Background: Canine factor VII (cFVII) deficiency, an autosomal recessive trait originally identified in research Beagles, is associated with a mild to moderate bleeding tendency.

Objective: Our aim was to identify and characterize the mutation causing cFVII deficiency. Methods: In order to sequence the coding regions of the cFVII gene, we cloned the cFVII cDNA. Genomic DNA and plasma from FVII-deficient Beagles and obligate carriers were utilized.

Results: In all FVII-deficient dogs, we identified a single causative G to A missense mutation in exon 5, encoding the second epidermal growth factor-like domain, resulting in substitution of glycine 96 by glutamic acid, with plasma FVII coagulant activity of â&#x2030;¤ 4% in affected Beagles. In vitro expression indicated that the majority (96%) of cFVII-G96E protein was retained intracellularly. In addition, analysis of purified recombinant wild-type and mutant cFVII proteins demonstrated reduced activity of the mutant (< 2%) compared with wild-type. Rotational thromboelastometry revealed a severe impairment of clotting activity in affected Beagles, and heterozygotes also exhibited changes in coagulation-based assays. Using a mutation-specific polymerase chain reaction/restriction digest that allows rapid identification of the G96E mutation, we surveyed a US research Beagle colony and identified a mutant allelic frequency of 31%.

Conclusions: We have identified a single causative mutation for cFVII deficiency that may have implications for pharmacotoxicologic research, because reduced FVII coagulant activity may alter hemostatic and/or cardiovascular endpoints in this commonly used animal species.

von Willebrand Disease Type I Reference

Venta, P.J., Brewer, G. J., Yuzbasiyan-Gurkan, V., Schall, W.D., Duffendeck, J inventors; VETGEN LLC, Michigan State University, University of Michigan, assignee. DNA encoding canine von Willebrand factor and methods of use. United States patent US 6,074,832. 2000 June 13.

Abstract

The complete sequence of the canine von Willebrand Factor cDNA and deduced amino acid sequence is provided. The mutation which causes von Willebrand's Disease in Scottish Terriers, a single base deletion in exon 4, has also been determined. Methods for detecting carriers of the defective vWF gene are also provided.

Von Willebrand Disease Type II Reference

Kramer JW, Venta PJ, Klein SR, Cao Y, Schall WD, Yuzbasiyan-Gurkan V. A von Willebrand's factor genomic nucleotide variant and polymerase chain reaction diagnostic test associated with inheritable type-2 von Willebrand's disease in a line of german shorthaired pointer dogs. Vet Pathol. 2004 May;41(3):221-8. doi: 10.1354/vp.41-3-221.

PMID: 15133170.

Abstract

Heritable, type-2 von Willebrand's disease (vWD) was studied in a line of German Shorthaired Pointers (GSPs) in which some members had a nucleotide variant in exon 28 of the von Willebrand factor (VWF) gene. A polymerase chain reaction (PCR) diagnostic test for the nucleotide variant was developed to establish the disorder's mode of inheritance and to eliminate it from the line. Thirty-six of the 49 GSPs in the line, 14 unrelated GSP controls, and 71 unrelated dogs of various breeds were tested for the presence of the variant nucleotide. All the dogs with a vWF antigen deficiency (<70% of normal) were either homozygous or heterozygous for the nucleotide variant. The variant was not located in any tested dog in the line or outside of the line with a vWF antigen value greater than 68%. Of the GSPs in the line tested, two were homozygous for the variant, 15 were heterozygous, and 19 were variant free. The collective evidence of this and other studies is consistent with the variant nucleotide being the cause of the type-2 vWD in this line of GSPs and German Wirehaired Pointers. The PCR diagnostic test for the variant nucleotide was successfully used to select and produce progeny that were variant free and vWD free. This test should be effective in the subsequent elimination of this same variant from other lines of dogs.

Overview

Factor VII Deficiency and von Willebrand Disease are bleeding disorders that often go undiagnosed in puppies because they are not detectable with routine blood work. These conditions could put a patient at risk for increased bleeding when undergoing a routine surgical procedure, such as spay or neuter. Genetic mutations can result in decreased amounts or malformations of factors necessary for blood clotting.

Relevant Breeds

Factor VII Deficiency Beagle, Alaskan Klee Kai, Airedale Terrier, Giant Schnauzer, Scottish Deerhound, American Foxhound, Finnish Hound, German Wirehaired Pointer, Irish Water Spaniel, Japanese Spitz, Miniature Schnauzer, Papillon/Phalene, Sealyham Terrier, and Welsh Springer Spaniel. von Willebrand Disease — Type I Doberman, Australian Terrier, Bernese Mountain Dog, Coton de Tulear, Doberman Pinscher, German Pinscher, Kerry Blue Terrier, Manchester Terrier, Papillon, Pembroke Welsh Corgi, Miniature Poodle, Standard Poodle, Toy Poodle, Red Setter, White Setter, Stabyhound, West Highland White Terrier, and others. von Willebrand Disease — Type II German Shorthaired Pointer, German Wirehaired Pointer, Barbet, Basenji, Border Collie, Chinese Crested Dog, German Spitz, Norwegian Elkhound, Old English Sheepdog, Portuguese Water Dog, and others.

Risk Associated with Variant Tested

Factor VII Deficiency is associated with a mild to moderate bleeding tendency. Patients at risk may not show obvious signs of illness under normal circumstances but could experience prolonged bleeding, bruising, and hematoma formation after surgery. von Willebrand Disease can range from very mild symptoms to more severe issues such as spontaneous internal bleeding (hematuria, hemarthrosis, hemoabdomen, and hemothorax).

Severity

Concentration of vWF

Structure of vWF

vWD Type I

Mild (can be variable)

Low

Normal

vWD Type II

Moderate / Severe

Low

Abnormal

vWD Type III

Severe

Absent

-

Limitations

There are additional known genetic mutations linked to clotting disorders not included in Igenity Canine Wellness. Those disorders are often or so severe that bleeding complications are evident immediately after birth and can be fatal.

Gene

• Factor VII Deficiency — cVII • von Willebrand Disease type I — von Willebrand factor gene exon 43 • von Willebrand disease type II — von Willebrand factor gene exon 28

Mode of Inheritance

• Factor VII deficiency — autosomal recessive • von Willebrand disease type I — autosomal dominant with incomplete penetrance • von Willebrand disease type II — autosomal recessive

Care Recommendations for Patients at Risk

• Additional diagnostic testing prior to surgery is recommended to assess clotting ability

• Consider pre-surgical treatment as needed • Avoid medications that interfere with clotting

Patients with mild cases of clotting disorders may have bruising or prolonged bleeding following surgery, blood draw, nail trim, or dental cleaning. © NEOGEN Corporation, 2021. NEOGEN and Igenity are registered trademarks of NEOGEN Corporation, Lansing, MI 48912 U.S.

02 Conditions

Exercise-induced Collapse (EIC)

Reference

Patterson, E. E., Minor, K. M., Tchernatynskaia, A. V., Taylor, S. M., Shelton, G. D., Ekenstedt, K. J., & Mickelson, J. R. (2008). A canine DNM1 mutation is highly associated with the syndrome of exercise-induced collapse. Nature Genetics, 40(10), 1235â&#x20AC;&#x201C;1239

Abstract

Labrador retrievers are the most common dog breed in the world, with over 200,000 new kennel club registrations per year. The syndrome of exercise-induced collapse (EIC) in this breed is manifested by muscle weakness, incoordination, and life-threatening collapse after intense exercise. Using a genome-wide microsatellite marker scan for linkage in pedigrees, we mapped the EIC locus to canine chromosome 9. We then used SNP association and haplotype analysis to fine map the locus, and identified a mutation in the dynamin 1 gene (DNM1) that causes an R256L substitution in a highly conserved region of the protein. This first documented mammalian DNM1 mutation is present at a high frequency in the breed and is a compelling candidate causal mutation for EIC, as the dynamin 1 protein has an essential role in neurotransmission and synaptic vesicle endocytosis.

Overview

Exercise-induced collapse (EIC) is a genetic condition that can result in collapse after just a few minutes of strenuous exercise. Many times dogs recover within about 30 minutes, but sometimes these events can be fatal. Affected dogs may not be ideal candidates for hunting or other physically demanding activities, but can still live a healthy life with the right lifestyle adjustments.

Relevant Breeds

Labrador Retrievers, Bouvier Des Flanders, Curly Coated Retrievers, Chesapeake Bay Retrievers, Boykin Spaniels, German Wirehaired Pointers, Old English Sheepdog, Cocker Spaniels, Pembroke Welsh Corgis, and other breeds, including mixed-breed dogs.

Risk Associated with Variant Tested

Only dogs who have two copies of the EIC variant are at risk for an episode of collapse. Carriers of the variant are not at risk for a clinical episode.

How likely are dogs at risk to have an episode of collapse?

Dogs at risk experience their first episode of collapse between five months and five years of age.

80%

of at risk dogs will have an episode of collapse before four years of age.

Limitations

Collapse may occur due to many other conditions including orthopedic disorders, heart failure, anemia, heart rhythm disturbances, respiratory problems, low blood sugar, cauda equina syndrome, myasthenia gravis, hypoadrenocorticism, and muscle disease.

Gene DNM1

Mode of Inheritance Autosomal recessive

Care Recommendations for Patients at Risk

• Recommend the owner monitor their dog very closely. If an episode of EIC should occur: • Make sure breathing is unobstructed • Help to cool the dog with water • Force the dog to rest until fully recovered • Occasionally episodes can be fatal — stop exercise at first sign of EIC

• Refrain from strenuous outdoor activities in hot weather • Phenobarbital can be a treatment option if alternative life style is not an option, but the mechanism and effectiveness are not well proven

Dogs at risk can live normal, healthy lives with proper monitoring and lifestyle adjustments. © NEOGEN Corporation, 2021. NEOGEN and Igenity are registered trademarks of NEOGEN Corporation, Lansing, MI 48912 U.S.

03 Conditions

Intervertebral Disk Disease (IVDD)

Reference

Brown EA, Dickinson PJ, Mansour T, Sturges BK, Aguilar M, Young AE, Korff C, Lind J, Ettinger CL, Varon S, Pollard R, Brown CT, Raudsepp T, Bannasch DL. FGF4 retrogene on CFA12 is responsible for chondrodystrophy and intervertebral disc disease in dogs. Proc Natl Acad Sci U S A. 2017 Oct 24;114(43):11476-11481. doi: 10.1073/pnas.1709082114. Epub 2017 Oct 11. PMID: 29073074; PMCID: PMC5664524.

Abstract

Chondrodystrophy in dogs is defined by dysplastic, shortened long bones and premature degeneration and calcification of intervertebral discs. Independent genome-wide association analyses for skeletal dysplasia (short limbs) within a single breed (PBonferroni = 0.01) and intervertebral disc disease (IVDD) across breeds (PBonferroni = 4.0 Ă&#x2014; 10â&#x2C6;&#x2019;10) both identified a significant association to the same region on CFA12. Whole genome sequencing identified a highly expressed FGF4 retrogene within this shared region. The FGF4 retrogene segregated with limb length and had an odds ratio of 51.23 (95% CI = 46.69, 56.20) for IVDD. Long bone length in dogs is a unique example of multiple disease-causing retrocopies of the same parental gene in a mammalian species. FGF signaling abnormalities have been associated with skeletal dysplasia in humans, and our findings present opportunities for both selective elimination of a medically and financially devastating disease in dogs and further understanding of the ever-growing complexity of retrogene biology.

Overview

Intervertebral disc disease (IVDD) is a premature degeneration of the intervertebral disc, the cushion located between the bones of the spine in the back (vertebrae). This degeneration can lead to disc rupture or herniation, often known as a slipped disc, which is very painful and can have serious implications on quality of life.

Healthy Spinal Cord

Hansen’s Type I IVDD

Relevant Breeds

The genetic mutation associated with IVDD risk is also correlated to chondrodystrophy, a defect in ossification of cartilage which results in short limbs. This genetic variant has been observed in the breeds below and may also be present in additional breeds not listed.

Basset Hound, Beagle, Bichon Frise, Cardigan Welsh Corgi, Cavalier King Charles Spaniel, Chesapeake Bay Retriever, Chihuahua, Chinese Crested, American Cocker Spaniel, Coton de Tulear, Dachshund, Dandie Dinmont Terrier, English Springer Spaniel, French Bulldog, Havanese, Jack Russell Terrier, Nova Scotia Duck Tolling Retriever, Pekingese, Pembroke Welsh Corgi, Poodle (Miniature and Toy), Portuguese Water Dog, Scottish Terrier, and Shih Tzu.

Risk Associated with Variant Tested

There are two genetic variants that researchers have identified to correlate to chondrodystrophy (short legs) in dogs. One variant is located on chromosome 12 (Brown, et al. 2017) and the other on chromosome 18 (Parker, et al. 2009). The genes where these mutations occur are involved in cartilage growth and bone development, however only the variant on CFA 12 has been linked to risk for IVDD. All dogs used as IVDD controls in the initial study (except for one — see limitations) carried at least one genetic variant for IVDD risk. Additional research supports that the presence of the risk variant for IVDD is associated with a lower age of onset and need for surgery across many breeds.

Limitations

In the initial research study, there was one dog with IVDD that did not carry a genetic variant for the disease. This dog was a rottweiler, a breed that is not chondrodystrophic. It is possible there are other causes of IVDD not attributable to this genetic variant, especially in non-chondrodystrophic breeds.

Gene FGF4

Mode of Inheritance Autosomal dominant

Care Recommendations for Patients at Risk • Recommend the owner monitor their dog very closely.

Clinical signs may include back pain and reluctance to move as well as lameness (difficulty walking) in the hind limbs or all four limbs • Maintain a healthy weight

• Use a harness, rather than a collar for walks on leash • Create a comfortable place for your dog to rest at floor level or install a ramp to a bed or couch to help prevent jumping off furniture • Consider low impact or solo exercise for your dog

Seek medical treatment immediately if pet has difficulty walking or neck/back pain. © NEOGEN Corporation, 2021. NEOGEN and Igenity are registered trademarks of NEOGEN Corporation, Lansing, MI 48912 U.S.

04 Conditions

Lens Luxation

References

Farias FH, Johnson GS, Taylor JF, Giuliano E, Katz ML, Sanders DN, Schnabel RD, McKay SD, Khan S, Gharahkhani P, et al. (2010). An ADAMTS17 splice donor site mutation in dogs with primary lens luxation. Invest Ophthalmol Vis Sci. 51(9):4716-21. DOI

Abstract

Purpose: To identify the genetic cause of isolated canine ectopia lentis, a well-characterized veterinary disease commonly referred to as primary lens luxation (PLL) and to compare the canine disease with a newly described human Weill-Marchesani syndrome (WMS)-like disease of similar genetic etiology.

Methods: Genome-wide association analysis and fine mapping by homozygosity were used to identify the chromosomal segment harboring the PLL locus. The resequencing of a regional candidate gene was used to discover a mutation in a splice donor site predicted to cause exon skipping. Exon skipping was confirmed by reverse transcription-polymerase chain reaction amplification of RNA isolated from PLL-affected eyes and from skin fibroblast cultures from PLL-affected dogs. An allelic discrimination assay was used to genotype individual dogs at the splice donor site mutation.

Results: The PLL locus was mapped to a 664-kb region of canine chromosome 3 containing regional candidate gene ADAMTS17. Resequencing ADAMTS17 revealed a GT-->AT splice-donor-site mutation at the 5â&#x20AC;&#x2122; end of intron 10. The predicted exon 10 skipping and resultant frame shift were confirmed with RNA derived from PLL-affected dogs. The ADAMTS17 mutation was significantly associated with clinical PLL in three different dog breeds.

Conclusions: A truncating mutation in canine ADAMTS17 causes PLL, a well-characterized veterinary disease, which can now be compared to a recently described rare WMS-like disease caused by truncating mutations of the human ADAMTS17 ortholog.

Overview

The lens is a structure in the eye that focuses light on the retina, which sends nerve impulses to the brain to form a visual image.

The lens is held in place by ligament-like structures called zonular fibers. When these fibers are weak or break, the lens can dislocate from its normal position and fall backwards (posterior luxation) or forward (anterior luxation).

Relevant Breeds

This genetic variant for lens luxation has been observed in the breeds below and may also be present in additional breeds not listed or mixed breed dogs.

American Eskimo Dog, American Hairless (Rat) Terrier, Australian Cattle Dog, Border Collie, Chinese Crested, Jack Russell Terrier, Jagd Terrier, Lakeland Terrier, Lancashire Heeler, Lucas Terrier, Miniature Bull Terrier, Norfolk Terrier, Norwich Terrier, Parson Russell Terrier, Patterdale Terrier, Rat Terrier, Russell Terrier, Sealyham Terrier, Teddy Roosevelt Terrier, Tenterfield Terrier, Tibetan Terrier, Toy Fox Terrier, Volpino Italiano, Welsh Terrier, Wire Fox Terrier, and Yorkshire Terrier.

Risk Associated with Variant Tested

Lens luxation is a recessive trait; however, carriers of the variant do appear to have a slightly increased risk of lens luxation. Average age of onset for primary lens luxation in dogs is 3–8 years of age. If lens luxation occurs in one eye, it is likely that the other eye will be affected later in life.

Lens displacement can occur into the back of the eye in posterior displacement, or the front of the eye in anterior displacement.

Anterior displacement tends to be more painful because it blocks the drainage of fluid from the eye, resulting in increased ocular pressure and glaucoma if not treated quickly.

Limitations

Not all cases of lens luxation are due to genetics. Lens luxation may also be secondary due to the following conditions: • Injury or trauma • Glaucoma • Intraocular tumors • Anterior uveitis • Collagen disorders • Idiopathic (cause unknown)

The prevalence of carriers is as high as 30% in some popular dog breeds.

Gene

ADAMTS17

Mode of Inheritance

Primary lens luxation has been shown to be a recessive trait, however, heterozygotes (carriers) do appear to have a slightly increased risk.

Care Recommendations for Patients at Risk Routine Eye Exams Prior to full lens luxation, an ophthalmologist may be able to detect lens subluxation or “wobble” of the lens as the zonular fibers begin to breakdown.

In Case of Emergency Pet parents of dogs at risk should be prepared on what signs to look for and what to do in case of an emergency. This plan should be shared with all caregivers of the pet along with veterinary contact information.

Anterior displacement of the lens is an emergency. Have a plan in place to detect and treat symptoms. © NEOGEN Corporation, 2021. NEOGEN and Igenity are registered trademarks of NEOGEN Corporation, Lansing, MI 48912 U.S.

05 Conditions

Urate Crystals and Bladder Stones

References

Bannasch, D., Safra, N., Young, A., Karmi, N., Schaible, R. S., & Ling, G. V. (2008). Mutations in the SLC2A9 gene cause hyperuricosuria and hyperuricemia in the dog.

PLoS Genetics, 4(11). https://doi.org/10.1371/journal.pgen.1000246

Abstract

Allantoin is the end product of purine catabolism in all mammals except humans, great apes, and one breed of dog, Dalmatians. Humans and Dalmatian dogs produce uric acid during purine degradation, which leads to elevated levels of uric acid in blood and urine and can result in significant diseases in both species.

The defect in Dalmatians results from inefficient transport of uric acid in both the liver and renal proximal tubules. Hyperuricosuria and hyperuricemia (huu) is a simple autosomal recessive trait for which all Dalmatian dogs are homozygous. Therefore, in order to map the locus, an interbreed backcross was used. Linkage mapping localized the huu trait to CFA03, which excluded the obvious urate transporter 1 gene, SLC22A12. Positional cloning placed the locus in a minimal interval of 2.5 Mb with a LOD score of 17.45. A critical interval of 333 kb containing only four genes was homozygous in all Dalmatians. Sequence and expression analyses of the SLC2A9 gene indicated three possible mutations, a missense mutation (G616T;C188F) and two promoter mutations that together appear to reduce the expression levels of one of the isoforms. The missense mutation is associated with hyperuricosuria in the Dalmatian, while the promoter SNPs occur in other unaffected breeds of dog. Verification of the causative nature of these changes was obtained when hyperuricosuric dogs from several other breeds were found to possess the same combination of mutations as found in the Dalmatian. The Dalmatian dog model of hyperuricosuria and hyperuricemia underscores the importance of SLC2A9 for uric acid transport in mammals.

Overview

Originally discovered in dalmatians, a genetic mutation has been found to result in the abnormal metabolism of purine, a component of high protein foods. The result is a high level of uric acid in the blood (hyperuricemia) and urine (hyperuricosuria). Given the right conditions and pH in the urinary bladder, this high level of uric acid can result in the formation of urinary crystals or even stones (uroliths) in the urinary bladder.

Relevant Breeds

Dalmatian, American Pit Bull Terrier, American Staffordshire Terrier, Australian Shepherd, Black Russian Terrier, Catahoula Leopard Dog, German Shepherd, Giant Schnauzer, Jack Russell Terrier, Labrador Retriever, Lagotto Romagnolo, Large Munsterlander, Parson Russell Terrier, Pitbull, Pomeranian, Russell Terrier, Small Munsterlander, Swedish Vallhund, Vizsla, Weimaraner, and others.

Risk Associated with Variant Tested

Not all dogs affected with the mutation for abnormal purine metabolism will suffer clinically from urinary crystals or stones. The development of crystals and stones appears to be multifactorial and in addition to genetics, urine composition, and anatomy also play a role. Male dogs are significantly more likely to have complications than females. The average age at which dalmatians typically develop stones is 4.5 years old.

Limitations

• The test does not account for other causes of hyperuricosuria, such as liver dysfunction or portosystemic shunts.

• The test does not indicate risk for other types of crystals or stones such as calcium oxalate, struvite, or cystine.

• There are other genetic mutations that cause urinary crystals and stones, but they are very rare in the general population.

Gene

SLC2A9

Mode of Inheritance Autosomal recessive

Care Recommendations for Patients at Risk • Recommend the owner monitor their dog very closely. Clinical symptoms include: • Dysuria (straining to urinate) • Hematuria (blood in the urine) • Avoiding foods with protein sources that are especially high in purines such as fish and organ meats

Eggs

Rice

• Urate urinary crystals can typically be treated with a prescription diet, but often times stones require surgery for removal • Urinalysis every 3–6 months • Ultrasound every 6–12 months

Whey

Wet Dog Food

Feed protein sources that are lower in purine content and consider canned or wet food to increase water intake.

Watch for signs of urinary discomfort including straining to urinate or blood in the urine. © NEOGEN Corporation, 2021. NEOGEN and Igenity are registered trademarks of NEOGEN Corporation, Lansing, MI 48912 U.S.

06 Conditions

Mammary Tumors

References

Melin, M., Rivera, P., Arendt, M., Elvers, I., Murén, E., Gustafson, U., Starkey, M., Borge, K.S., Lingaas, F., Häggström, J., Saellström, S., Rönnberg, H., Lindblad-Toh, K. (2016). Genome-Wide Analysis Identifies Germ-Line Risk Factors Associated with Canine Mammary Tumours. PLoS Genetics, 12(5).

Abstract

Canine mammary tumors (CMT) are the most common neoplasia in unspayed female dogs. CMTs are suitable naturally occurring models for human breast cancer and share many characteristics, indicating that the genetic causes could also be shared. We have performed a genome-wide association study (GWAS) in English Springer Spaniel dogs and identified a genome-wide significant locus on chromosome 11 (praw = 5.6x10-7, pperm = 0.019). The most associated haplotype spans a 446 kb region overlapping the CDK5RAP2 gene. The CDK5RAP2 protein has a function in cell cycle regulation and could potentially have an impact on response to chemotherapy treatment. Two additional loci, both on chromosome 27, were nominally associated (praw = 1.97x10-5 and praw = 8.30x10-6). The three loci explain 28.1±10.0% of the phenotypic variation seen in the cohort, whereas the top ten associated regions account for 38.2±10.8% of the risk. Furthermore, the ten GWAS loci and regions with reduced genetic variability are significantly enriched for snoRNAs and tumor-associated antigen genes, suggesting a role for these genes in CMT development. We have identified several candidate genes associated with canine mammary tumors, including CDK5RAP2. Our findings enable further comparative studies to investigate the genes and pathways in human breast cancer patients.

Overview

Mammary tumors are the most common type of cancer in female dogs. Like humans, risk for developing this type of cancer is complex and dependent on many genetic factors as well as additional factors such as the hormone estrogen.

Relevant Breeds

The genetic variants associated with this test has only been studied in English Springer Spaniels. Ongoing research will help to reveal the impact of these variants in dogs of other breeds.

Risk Associated with Variant Tested

Although canine mammary tumors are quite common, the level of risk associated with the variant tested across breeds is not known. Several research studies have been conducted to investigate genetic predisposition to mammary tumors in dogs and have identified multiple genes that may impact risk. These findings suggest that mammary tumors have a complex genetic background and are due to a variety of different genetic and environmental factors.

91%

of affected dogs in the initial study carried at least one risk allele.

Limitations

• Other genes and risk loci have been implicated in the development of mammary tumors and are not included in this test.

• This variant has not been well evaluated in breeds other than English Springer Spaniels.

Gene

CDK5RAP2

Mode of Inheritance

Mammary tumors is a complex genetic trait — the underlying inheritance is not yet well understood.

Early spay can dramatically decrease risk of mammary cancer 1 in 4 unspayed females will be diagnosed with mammary cancer in their lifetime

The risk goes down to 8% if spayed prior to the second heat cycle

The risk goes down even further to 0.5% if spayed prior to first heat cycle

Care Recommendations for Patients at Risk

• Spay prior to the first heat cycle: Risk of mammary tumors can be significantly decreased by performing ovariohysterectomy (spay) prior to the first heat cycle • Recommend the owner monitor their dog very closely Clinical signs may include:

• • • • •

Lumps under the skin on the abdomen Ulceration of the skin over the mammary glands Pain Red (blood) or yellow (pus) discharge Generalized weakness, lethargy, or poor appetite

The best prognosis for mammary cancer is when tumors are identified and treated early. Monitoring for masses at home and special evaluation during veterinary clinic exams will facilitate early diagnosis and intervention. © NEOGEN Corporation, 2021. NEOGEN and Igenity are registered trademarks of NEOGEN Corporation, Lansing, MI 48912 U.S.

07 Conditions

Pancreatitis

Reference

Bishop, M. A., Xenoulis, P. G., Levinski, M. D., Suchodolski, J. S., & Steiner, J. M. (2010). Identification of variants of the SPINK1 gene and their association with pancreatitis in Miniature Schnauzers. American Journal of Veterinary Research, 71(5), 527â&#x20AC;&#x201C;533. https://doi.org/10.2460/ajvr.71.5.527

Abstract

Objective: To evaluate the serine protease inhibitor, Kazal type 1 (SPINK1) gene for variants and to determine their possible association with pancreatitis in Miniature Schnauzers.

Animals: 39 Miniature Schnauzers with pancreatitis, 25 healthy Miniature Schnauzers, and 23 healthy dogs of other breeds.

Procedures: The entire canine SPINK1 gene with its intron-exon boundaries was initially sequenced in 22 Miniature Schnauzers. Then, 2 regions of the gene were sequenced in 65 additional canine DNA samples at the locations of variants identified in the initial sequencing of the entire SPINK1 gene.

Results: Analysis of the SPINK1 gene in Miniature Schnauzers revealed 3 closely associated variants in healthy Miniature Schnauzers and Miniature Schnauzers with pancreatitis. These variants consisted of 2 missense mutations in the second exon (N20K and N25T) and a poly T insertion in the third intron that was near the boundary of exon 3 (IVS3+26-27ins(T)33-39,15_61dup11). Pancreatitis was significantly associated with homozygous alleles for these 3 variants in Miniature Schnauzers. In healthy dogs of other breeds, only the 2 exon variants were identified.

Conclusions and clinical relevance: Variants of the SPINK1 gene may be associated with the development of pancreatitis in Miniature Schnauzers.

Overview

Pancreatitis is an inflammation of the pancreas, an organ which produces enzymes to help in digesting food and produces hormones such as insulin, which regulate blood sugar metabolism. The condition can occur suddenly (acute) or develop slowly over time (chronic).

Relevant Breeds

The genetic variants associated with this test has only been well studied in Miniature Schnauzers. Ongoing research will help to reveal the impact of these variants in dogs of other breeds.

Risk Associated with Variant Tested

Researchers at Texas A&M discovered three variants in the SPINK gene that were significantly associated with pancreatitis in a group of Miniature Schnauzers previously diagnosed with pancreatitis. Initial research suggests that Miniature Schnauzers diagnosed with pancreatitis are 21.7 times as likely to carry a risk allele than healthy dogs of the same breed over the age of five years.

Limitations

Not all dogs with the risk variant will eventually become clinically ill. Pancreatitis is likely a complex genetic trait and influenced by other environmental factors such as obesity, trauma, high-fat diets, pharmaceuticals, endocrinopathies, and hypertriglyceridemia.

These risk factors may result in patients suffering from pancreatitis that are not at risk genetically.

Gene

SPINK1

Mode of Inheritance

Pancreatitis is a complex genetic trait — the underlying inheritance is not yet well understood.

Care Recommendations for Patients at Risk • Avoid feeding high-fat diets including table scraps • Consider bringing the pet’s regular diet while boarding or staying away from home • Maintain a healthy weight, obese dogs are at higher risk for pancreatitis

Fever

Diarrhea

Poor Appetite

• Recommend the owner monitor their dog very closely.

Clinical symptoms include: fever, diarrhea, poor appetite, fatigue, vomitting, and stomach pain

Fatigue

Vomitting

Avoid feeding table scraps, especially those high in fat. Keep at-risk patients within a healthy weight range. © NEOGEN Corporation, 2021. NEOGEN and Igenity are registered trademarks of NEOGEN Corporation, Lansing, MI 48912 U.S.

Stomach Pain

08 Conditions

Social Behavior

Reference

vonHoldt BM, Shuldiner E, Koch EJ, Kartzinel RY, Hogan A, Brubaker L, Wanser S, Stahler D, Wynne CDL, Ostrander EA, Sinsheimer JS, Udell MAR. (2017). Structural variants in genes associated with human Williams-Beuren syndrome underlie stereotypical hypersociability in domestic dogs. Science Advances. 3(7).

Abstract

Although considerable progress has been made in understanding the genetic basis of morphologic traits (for example, body size and coat color) in dogs and wolves, the genetic basis of their behavioral divergence is poorly understood. An integrative approach using both behavioral and genetic data is required to understand the molecular underpinnings of the various behavioral characteristics associated with domestication. We analyze a 5-Mb genomic region on chromosome 6 previously found to be under positive selection in domestic dog breeds. Deletion of this region in humans is linked to Williams-Beuren syndrome (WBS), a multisystem congenital disorder characterized by hypersocial behavior. We associate quantitative data on behavioral phenotypes symptomatic of WBS in humans with structural changes in the WBS locus in dogs. We find that hypersociability, a central feature of WBS, is also a core element of domestication that distinguishes dogs from wolves. We provide evidence that structural variants in GTF2I and GTF2IRD1, genes previously implicated in the behavioral phenotype of patients with WBS and contained within the WBS locus, contribute to extreme sociability in dogs. This finding suggests that there are commonalities in the genetic architecture of WBS and canine tameness and that directional selection may have targeted a unique set of linked behavioral genes of large phenotypic effect, allowing for rapid behavioral divergence of dogs and wolves, facilitating coexistence with humans.

Overview

Social behavior is a complex trait shaped by both environment and genetics. Early life experiences and training are crucial to shaping adult behavior, but the personality of each dog is also dependent on their genetics.

Relevant Breeds All

Limitations

The DNA variants identified contribute towards shaping human-directed social behavior, but behavior is complex and influenced by many other experiences including environment, training, and other unknown genetic factors. The test does not predict a future behavioral outcome or guarantee that an animal will or will not be anxious, aggressive, etc.

Gene

GTF2I and WBSCR17

Mode of Inheritance

Social behavior is a complex genetic trait — the underlying inheritance is not yet well understood.

Discuss Behavior in the Exam Room

Understanding the genetic predisposition for behavioral traits such as hypersociability can help veterinary staff and pet parents create an ideal environment and training program for pets to be happy and thrive.

Customize vet visits and exams based on patient’s social preferences.

Dogs that carry a higher number of mutations may prefer an environment where someone is home during the day.

Consider daycare or drop-in visits.

Social behavior predisposition could influence a pet parent’s choice for a boarding facility, in-home care, or other options while away from home.

.

Some dogs may enjoy attending events with lots of people, while others may prefer to stay home or go to play independently.

Awareness of genetic influence on personality can help patients live a happy life. © NEOGEN Corporation, 2021. NEOGEN and Igenity are registered trademarks of NEOGEN Corporation, Lansing, MI 48912 U.S.

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