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Veterinary Genetics Laboratory

The NC State CVM Veterinary Genetics Laboratory offers genetic testing for genetic disorders in specific canine and feline breeds. Learn additional details about our current research programs are below and see if your pet qualifies for participation!

Breed Specific Genetic Disorders

Understanding Cardiomyopathy (HCM) in your Cat

Hypertrophic cardiomyopathy (HCM) is the most common form of heart disease in the cat. Affected cats can develop a heart muscle that is abnormally thick (hypertrophy) and does not function properly. They are at risk of sudden death, developing heart failure (shortness of breath) or developing blood clots which can cause paralysis. In many, many cats this disease is inherited. In two breeds of cats, the Maine Coon and the Ragdoll, a genetic mutation has been identified and a DNA test for HCM can be performed.
In many other breeds we know this is an inherited disease but a genetic mutation has not yet been identified. Our lab is currently working on research projects on many of these breeds including the Sphynx and the Bengal. If you are a breed organization who would like our assistance in this area, please ask!

Since genetic testing is not available for all breeds and is not an absolute, we recommend screening by echocardiography as well for all cats used for breeding that are a breed at risk for inherited HCM. Breeds of concern include Sphynx, Bengal, Maine Coon, Ragdoll, Siberian, Scottish Fold, Norwegian Forest Cat and Persian among others.
Additional information by breed:

  • Maine Coon: Maine Coon cats get a form of HCM that usually does not show up until they are an adult although the genetic mutation is present at birth… read more here.
  • Ragdoll: Ragdoll cats get a form of HCM that usually does not show up until they are an adult although the genetic mutation is present at birth… read more here.

Boxer Cardiomyopathy (Boxer Arrhythmogenic Right Ventricular Cardiomyopathy; ARVC)

Boxer dogs suffer from an inherited heart disease named Boxer Cardiomyopathy (also called Boxer ARVC). Affected dogs often develop the disease at middle age (5-7 years of age) but some can develop it a bit younger. Affected dogs may have fainting episodes and some die suddenly. A very small percentage of dogs develop heart failure and suffer from shortness of breath and coughing. Your veterinarian may observe ventricular premature beats (VPCs) on and ECG or may recommend screening your dog by having them wear a 24 hour Holter monitor at home to see if he/she is having these abnormal heart beats when they are in their home setting.

We have identified a genetic deletion in an important cardiac gene. It would appear that as many as 40% of Boxers have this mutation. The disease is referred to as having “incomplete penetrance”. This means that even if a dog has the genetic mutation, the mutation may not actually penetrate or lead to the development in full disease in that dog. DNA test results will indicate if the dog has the mutation on 1 copy of its 2 gene copies (called heterozygous) or both gene copies (homozygous).

Once you run the DNA test we will send you results that state your dog’s results are either:

  • Negative – This means that your dog does not have the genetic mutation for Boxer cardiomyopathy. However, this does not mean that your dog can never get heart disease or abnormal heart beats like VPCs since there may be other causes for these. However, it means that your dog will not get cardiomyopathy from the Boxer DNA mutation.
  • Positive Heterozygous – This means that your dog has 1 copy of the genetic mutation and 1 copy of a normal gene. Since this is a disease with incomplete penetrance, some dogs with the mutation will not ever show the disease, however about 80% will. Therefore if your dog is positive heterozygous for the mutation we would recommend annual screening for signs of the abnormal heart beats (VPCs) with a 24 hour Holter monitor after the age of 3 years. Dogs with abnormal heart beats may benefit from a medication called an antiarrhythmic. Many affected dogs will live very comfortably on these medications for years. Breeding recommendations: Since it is estimated that about 40% of the Boxer population has the deletion mutation we do not recommend withholding all positive heterozygous dogs out of the breeding program since this would have a significant negative impact on the breed. Although most dogs that are positive heterozygous do not get sick from the disease it may be reasonable to consider breeding these dogs to a Negative dog, screening the puppies and trying to select a Negative puppy to keep as a replacement breeding animal in the next litter or so. Overtime this will gradually reduce the prevalence of the disease in the breed. We would never recommend breeding a positive heterozygous dog to a positive heterozygous dog since this could produce homozygous dogs which are very likely to become sick from this disease.
  • Positive Homozygous– This means that your dog has 2 copies of the genetic mutation. It has the highest risk of developing the more severe form of the disease and has 100% chance of passing the mutation on to all of its puppies. It should be monitored annually by your veterinarian after it is 1 year of age. After 3 years of age it should have an annual Holter monitor and a careful physical examination by your veterinarian. We would not recommend using these dogs for breeding purposes.

Doberman pinscher Dilated Cardiomyopathy

Doberman pinschers suffer from an inherited heart disease that may result in sudden cardiac death or the development of congestive heart failure which may result in shortness of breath or coughing. Affected dogs usually develop the disease between 5 and 7 years of age. Screening for early disease may include annual echocardiography and Holter monitoring to look for abnormal heart beats.

Some affected dogs have a genetic mutation in a PDK4 gene, a gene that is important for the heart’s energy. The disease is referred to as having “incomplete penetrance”. This means that even if a dog has the genetic mutation, the mutation may not actually penetrate or lead to the development in full disease in that dog. About 65 % of dogs that have the mutation will eventually show the disease. DNA test results will indicate if the dog has the mutation on 1 copy of its 2 gene copies (called heterozygous) or both gene copies (homozygous).

Once you run the DNA test we will send you results that state your dog’s results are either:

  • Negative– This means that your dog does not have the genetic mutation for Doberman pinscher cardiomyopathy. However, this does not mean that your dog can never get heart disease since there are likely many other causes for heart disease in the Doberman pinscher. However, it does mean that your dog will not get cardiomyopathy from the known Doberman pinscher DNA mutation.
  • Positive Heterozygous – This means that your dog has 1 copy of the genetic mutation and 1 copy of a normal gene. Since this is a disease with incomplete penetrance, some dogs with the mutation will not ever show the disease, however about 65 % will. Therefore if your dog is positive heterozygous for the mutation we would recommend annual screening for signs of the abnormal heart beats (VPCs) with a 24 hour Holter monitor after the age of 4 years.Breeding recommendations: If the dog has many other positive trails it may be reasonable to consider breeding these dogs to a Negative dog, screening the puppies and trying to select a Negative puppy to keep as a replacement breeding animal in the next litter or so. Over time this will gradually reduce the prevalence of the disease in the breed. We would never recommend breeding a positive heterozygous dog to a positive heterozygous dog since this could produce homozygous dogs which are very likely to become sick from this disease.
  • Positive Homozygous– This means that your dog has 2 copies of the genetic mutation. It has the highest risk of developing the disease and has 100% chance of passing the mutation on to all of its puppies. Your dog should be monitored annually by your veterinarian after it is 3 years of age. We would not recommend using these dogs for breeding purposes if possible.

Newfoundland Subvalvular Aortic Stenosis (SAS)

Newfoundlands have an inherited heart defect referred to as subvalvular aortic stenosis (SAS). This is a defect located below the aortic valve of the heart. Dogs with the severe form of the disease may die suddenly, often before 2 years of age. Your veterinarian may be concerned that your Newfoundland has this trait if they detect a heart murmur when they evaluate your dog. The diagnosis can be confirmed with echocardiography by a veterinary cardiologist. Although it is inherited sometimes the parents can have a very subtle form of the disease that can not be clinically detected.

We identified a genetic mutation for Newfoundland SAS in a gene that encodes for an important cardiac development gene and we recommend screening breeding animals to help remove the prevalence of this mutation in this breed. The disease is referred to as having “incomplete penetrance”. This means that even if a dog has the genetic mutation, the mutation may not actually penetrate or lead to the development in full disease in that dog. DNA test results will indicate if the dog has the mutation on 1 copy of its 2 gene copies (called heterozygous) or both gene copies (homozygous).

Once you run the DNA test we will send you results that state your dog’s results are either:

  • Negative – This means that your dog does not have the genetic mutation for Newfoundland SAS it should not be able to pass SAS on to its puppies.
  • Positive Heterozygous – This means that your dog has 1 copy of the genetic mutation and 1 copy of a normal gene. Since this is a disease with incomplete penetrance, some dogs with the mutation will not ever show the disease.
    Breeding recommendations: If the dog has many other positive trails it may be reasonable to consider breeding these dogs to a Negative dog, screening the puppies and trying to select a Negative puppy to keep as a replacement breeding animal in the next litter or so. Over time this will gradually reduce the prevalence of the disease in the breed. We would never recommend breeding a positive heterozygous dog to a positive heterozygous dog since this could produce homozygous dogs which are very likely to become sick from this disease.
  • Positive Homozygous– This means that your dog has 2 copies of the genetic mutation and has 100% chance of passing the mutation on to all of its puppies. We would not recommend using these dogs for breeding purposes if possible.

Rhodesian Ridgeback Inherited Arrhythmia (RR IVA)

Rhodesian Ridgeback Inherited Arrhythmia (RR IVA) is an inherited disease that results in an abnormality of the cardiac electrical system leading to the development of abnormal heart beats (ventricular premature beats (VPCs). In some cases these abnormal heart beats can result in sudden death.  It appears that the most severe disease may be present between 6 and 30 months of age and many dogs appear to outgrow the problem.

A genetic test can be performed to determine if your dog has the DNA mutation that will put him/her at risk for the disease.

At this time we recommend that dogs that have the DNA mutation have a Holter monitored performed occasionally between 6 and 30 months of age to determine if they are having abnormal heart beats that should be more closely monitored or may indicate a need for treatment.

Our Team

Leadership

Kathryn Meurs, DVM, PhD Diplomate ACVIM (Cardiology)

Professor, Associate Dean for Research and Graduate Studies

Contact:

kate_meurs@ncsu.edu

Department Staff