Maine Coon Cat Hypertrophic Cardiomyopathy (HCM)

Hypertrophic cardiomyopathy (HCM) is a common heart disease characterized by thickened and enlarged heart tissue. This disease decreases cardiac output, which can result in thrombus formation and congestive heart failure. In Maine Coons, the age of presentation of disease is variable. Many cats develop this disease after three years of age, though some will not develop until much older, 6-8 years of age.

A genetic mutation (MYBPC3) has been identified in Maine Coons cats in association with HCM. HCM is a disease of incomplete penetrance. Some Maine Coons with the genetic mutation may not show the disease until they get older, and some individuals with the mutation may never show the disease. In addition, a Maine Coon that is negative for this mutation may still develop HCM. However, results from our genetic tests can be beneficial in guiding breeding practices and potential therapeutic measures.

Testing Prices:

Maine Coon HCM = $35.00 per cat

Maine Coon Litter Discount = $25.00 per kitten

Sample Type for Submission:

Acceptable samples include a cheek swab or 1-2 mL whole blood collected in an EDTA tube. If these sample types are unavailable, please reach out to us at cvm-cardiacgenetics@ncsu.edu for more information. Alternative sample types may result in an additional charge.

Explanation of Results:

Two copies of each gene are inherited, one from each parent. Possible results include:

Negative

Cats have two copies of the normal gene, which is not associated with the development of HCM. They cannot transmit this mutation to their offspring.

Positive Heterozygous

Cats have one copy of the normal gene and one copy of the mutated gene. Heterozygous cats are more likely to develop a mild form of disease than positive homozygous cats.

Positive Homozygous

Cats have two copies of the mutated gene, which is associated with HCM. They will transmit one copy of the mutation to their offspring. Homozygous cats are more likely to develop a more severe form of disease than positive heterozygous cats.

Positive cats are recommended to have annual evaluation by an echocardiogram and discussion with a veterinarian for treatment options if hypertrophy develops. 

Other factors likely contribute to this condition in cats, and a negative result does not rule out the presence of a different mutation that could cause a similar genetic disorder or trait.

Breeding Recommendations:

Breeding decisions should be made carefully and in discussion with your veterinarian. We cannot give specific breeding recommendations regarding your cat, but we advise to consider these genetic results as well as the overall health of the line. The goal is to reduce the prevalence of these disease-associated mutations while maintaining high quality diversity within the population.