7 Genetic Diseases Common in British Shorthairs — Early Warning Signs of Heart Disease

ImmunityBreed HealthMeongsiljang Veterinary Advisory Board

We’ve compiled a list of heart, kidney, and blood disorders that British Shorthairs and Longhairs are genetically predisposed to, along with early warning signs owners can spot at home and recommended screening schedules.

What Are British Shorthair Genetic Diseases?

A gray British Shorthair cat lying on a cushion

British Shorthair and Longhair cats are medium-to-large breeds that require careful monitoring for genetic heart, kidney, and blood disorders. The key to their care is regular check-ups even when they show no symptoms. Hypertrophic cardiomyopathy and polycystic kidney disease often progress silently for years before suddenly manifesting as respiratory distress or kidney failure. Therefore, it is advisable to have an echocardiogram and renal ultrasound performed every one to two years starting from the age of one.

Top 5 Genetic Diseases to Watch For

Here are five key points British Shorthair owners should keep in mind:

Hypertrophic Cardiomyopathy (HCM): This is the most common heart muscle disease in cats, characterized by thickened heart muscle that impairs blood circulation.

Polycystic Kidney Disease (PKD): A hereditary condition in which fluid-filled cysts gradually enlarge in the kidneys, eventually leading to kidney failure.

Blood Type Incompatibility: Cats can experience adverse reactions during blood transfusions or when giving birth if blood types are incompatible, so it is advisable to determine your cat’s blood type in advance.

Urinary Tract Stones: Be vigilant about the formation of struvite and calcium oxalate stones.

Periodontal Disease: Consistent oral care is essential from an early stage to prevent the buildup of tartar.

Hypertrophic Cardiomyopathy: Why Is It Common in British Shorthairs?

Hypertrophic cardiomyopathy (HCM) is a condition in which the heart muscle thickens, narrowing the internal space of the left ventricle. According to veterinary cardiology textbooks, HCM is the most common myocardial disease in cats. It is inherited in an autosomal dominant pattern, but with incomplete penetrance and variable expression among individuals. Unlike breeds such as the Maine Coon and Ragdoll, in which the causative genetic mutation (MYBPC3) has been clearly identified, no standardized single-gene mutation has been identified in British Shorthairs. However, because this disease can occur in a familial pattern within a family line, it is advisable to have regular cardiac ultrasound examinations starting from a young age if there is a family history of heart disease.

A British Shorthair undergoing an echocardiogram

Seek Veterinary Care Immediately If You See These Signs

If you notice any of the following symptoms, seek veterinary care within 24 hours. In hypertrophic cardiomyopathy, the first signs often indicate an emergency. • Breathing with an open mouth and panting • A resting respiratory rate exceeding 40 breaths per minute • Sudden weakness or coldness in the hind legs (possible blood clot) • Pale or bluish gums • Sudden loss of appetite and hiding

Polycystic Kidney Disease (PKD) Check Points

Polycystic kidney disease is a genetic condition in which small, fluid-filled cysts form in the kidneys and gradually enlarge with age. Although it was first identified in Persian cats, it is also frequently found in British Longhairs due to their breeding history with Persians. A single kidney ultrasound around one year of age can relatively accurately determine the presence or absence of cysts. Once diagnosed, the key management strategies include feeding a diet that minimizes kidney strain, ensuring adequate hydration, and monitoring kidney values every six months.

A British Longhair drinking water from a water dispenser

Recommended Screening Schedules by Genetic Disease

Item	Hypertrophic Cardiomyopathy	Polycystic Kidney Disease	Blood type test
First test timing	1 year of age	1 year of age	Right after adoption
Test method	Echocardiography	Kidney ultrasound	Blood test
Recheck interval	1–2 years	1 year	Once is sufficient
Estimated cost range	Varies by checkup price	Varies by checkup price	Varies by checkup price

Costs vary greatly by hospital and region, so they have been omitted. Please call to confirm before visiting.

Blood Type B: Why You Should Pay Attention

In some breeds, including British Shorthairs, the prevalence of blood type B is relatively high. While this typically poses no issues, it becomes critical in two specific scenarios. First, blood typing is mandatory for both the donor and recipient before any transfusion; administering incompatible blood can trigger an acute hemolytic transfusion reaction. Second, if a mother with blood type B gives birth to kittens with blood type A (or AB), the kittens are at immediate risk of neonatal isoerythrolysis after consuming her colostrum. In such cases, these kittens may need to be separated from their mother for the first two to three days of life. A single blood type test immediately after adoption can significantly reduce these lifelong risks.

Lifelong Care British Shorthair Owners Must Provide

While genetic diseases can’t be completely prevented, you play a crucial role in slowing their progression. • Weight management: Excess weight puts added strain on the heart and joints. • Hydration: Protect your cat’s kidneys by providing fresh water and incorporating wet food. • Annual check-ups: One to two comprehensive exams per year are recommended; after age 8, every six months is advised. • Share family history: Let your veterinarian know about the health information of your cat’s parents, which you received at adoption.

Reviewed by a veterinarian

Dr. Tony — Punnawat Phongkittirak

Veterinarian

A veterinarian who majored in veterinary medicine at Khon Kaen University, Thailand, and completed the IVSA program at North Carolina State University in the United States. Drawing on clinical experience at animal hospitals, he works in the pet healthcare field and is dedicated to building a digital care environment that connects pet parents with veterinarians.

Frequently Asked Questions

Do all British Shorthairs get hypertrophic cardiomyopathy?

Not at all. While the condition is somewhat more common in this breed than in other cats, many individuals live their entire lives without ever showing symptoms. Since it can progress silently, having an echocardiogram performed at one year of age can provide peace of mind.

Is genetic testing really necessary?

Unlike Maine Coons and Ragdolls, there is no widely available standardized single-gene test for British Shorthairs. Instead of genetic testing, heart and kidney ultrasound screenings after the age of one are more practically beneficial.

How long can a pet live with polycystic kidney disease?

It depends on the size of the cyst and the rate of kidney function decline. Even after diagnosis, many pets can enjoy a normal lifespan with proper dietary management and regular check-ups. Don’t lose hope—please monitor your pet’s kidney values every six months.

Should I postpone adoption if my cat is blood type B?

Not at all. There are no issues in daily life. However, to be prepared for emergency blood transfusions or breeding situations, both the pet owner and the veterinarian should know the pet's blood type in advance.

Primary vs. Secondary Veterinary Hospitals: A Comparison

Comparing Dog Vaccine Types (3-way, 5-way, 7-way): Differences and How to Choose

Pet Insurance Enrollment Timing Comparison: When Is the Most Advantageous Time to Enroll?

Chow Chow Entropion Precautions and Age-Specific Lifelong Health Management Guide

Lens Luxation in Jack Russell Terriers — Early Detection to Prevent Blindness and Lifelong Health Care

Boston Terrier Corneal Injury — Symptoms, Causes, and Age-Specific Lifelong Care

Shih Tzu Eye Diseases — A Complete Guide from Symptoms and Causes to Lifelong Age-Specific Care

Great Dane Gastric Dilatation-Volvulus (GDV) — From Warning Signs to Prevention and Lifelong Management

Degenerative Myelopathy (DM) in Welsh Corgis — From Early Symptoms to Lifelong Age-Specific Care

Scottish Fold Kidney Screening: A Lifetime Care Guide Including Cartilage Disorders

References

[1] Textbook of Cardiovascular Medicine in Dogs and Cats — Hypertrophic Cardiomyopathy chapter

[2] Small Animal Critical Care Medicine, 3rd Ed — Feline Cardiomyopathy Classification

[3] 수의내과학 교과서 — 고양이 다낭성 신장병(PKD) 단원