By Dr. Becker
Most discussions about genetic diseases in pets involve dogs, because more dogs than cats are purebred and acquire specific inherited traits passed from one generation to the next. But what about our feline family members? Do they acquire genetic diseases as well?
Unlike purebred dogs, the majority of domestic kitties reproduce without interference from humans. This helps to dilute disease-causing genes in their lineage, with the result that they acquire inherited disorders less often. However, pedigreed cats tend to follow a more predictable pattern of disease inheritance similar to their canine counterparts.
Pet insurance carriers and animal hospital databases keep records of the most frequently diagnosed diseases in kitties, which are "… complexly inherited and involve combinations of multiple genes and environmental factors," according to Dr. Jerold S. Bell of the Cummings School of Veterinary Medicine at Tufts University.1
"Genetic diseases should be recognized in practice because they must be treated as chronic illnesses — not episodic diseases," says Bell, who lists the top five genetic diseases of cats as feline lower urinary tract disease (FLUTD), diabetes mellitus, lymphocytic or plasmacytic inflammatory disease, polycystic kidney disease and hypertrophic cardiomyopathy.
It's important to keep in mind that just because some veterinarians believe certain disorders are inherited in certain breeds, it doesn't mean your cat of that breed is destined to acquire those conditions. There are steps you can take to help prevent your kitty from acquiring diseases to which she may be predisposed, and there are ways to successfully treat or effectively manage existing genetic conditions.
Feline Lower Urinary Tract Disease
Feline lower urinary tract disease (FLUTD) is actually a group of conditions affecting the bladder or urethra of cats, including cystitis (bladder inflammation), bacterial infection and urethral blockage. According to Bell, FLUTD is the most frequently seen inherited condition in domestic cats.
FLUTD isn't passed from cat to cat, as evidenced by the fact that it often occurs in just one kitty in a multi-cat household. Persians may be at increased risk for lower urinary tract problems, while Siamese may be at decreased risk. In one study, when exposed to stressors, only kitties predisposed to FLUTD developed symptoms,2 and their gene expression profiles were similar to those found in humans with interstitial cystitis (bladder pain syndrome).
If your cat has FLUTD: She needs to drink more water, urinate more and eat an anti-inflammatory, moisture-rich diet of either human-grade canned food or a fresh, nutritionally balanced whole food diet. It's also important to identify potential sources of food allergies.
A urinary tract infection may be an underlying cause of your kitty's FLUTD, but too often, antibiotics are given without a culture and sensitivity test. If your vet suggests antibiotics to kill bacteria present in a sterile urine sample, insist on a bacterial culture to identify the correct treatment.
It's also extremely important to focus on reducing or eliminating potential stressors in your cat's life. Stress typically has three different sources: environmental, immunologic and nutritional. According to one study, cats with feline idiopathic cystitis (FIC) showed 75 to 80 percent improvement in symptoms when they were fed at the same time each day, their litter boxes stayed in the same location and regular playtime was encouraged.3
Any cat can develop diabetes mellitus, but Bell cites studies that show the condition may be more prevalent in certain breeds, including the Burmese, Siamese, Norwegian Forest, Russian Blue and Abyssinian. Obesity is most definitely a predisposing factor for diabetes in kitties, and in my experience, regardless of the cat's genetics, being overweight and eating a carbohydrate-laden dry food diet are by far the biggest risk factors for diabetes.
If your cat has diabetes mellitus: Treatment of diabetes in cats is complex and time consuming. It involves regular monitoring of blood glucose levels, ongoing dietary adjustments, insulin given by injection or oral glucose-regulating drugs, and keeping a constant, careful eye on your sick kitty.
Prevention is obviously the best "cure" for this disease, so I hope you'll give serious consideration to the importance of nutrition, exercise and maintaining your cat at a healthy weight in preventing diabetes and other serious diseases. You can help him stay trim by feeding a portion controlled, moisture-rich, balanced, species-appropriate diet consisting of a variety of unadulterated protein sources and healthy fats, and specific nutritional supplements as necessary.
Kitty also needs to get moving. I recommend a minimum of 20 minutes of daily exercise. You'll need to get creative to keep your cat physically active, but it can be done, usually through lots of feather chasing games.
Lymphocytic or Plasmacytic Inflammatory Disease
Interestingly, this impossible-to-pronounce immune-mediated inflammatory condition in cats typically takes the form of either gingivostomatitis (a very painful, chronic disease of the mouth), or as inflammatory bowel disease (IBD). Fortunately, it's rare that a cat develops both forms.
Siamese and other Asian breeds are predisposed to the IBD form of the disease. Other risk factors include food intolerances, sensitivity to the body's own microbiome and behavioral stress. According to Bell, cats affected by this disease "… show a lifelong propensity to inflammatory cell infiltration that does not occur in other cats in the same household."
If your cat has gingivostomatitis: View my video and article on feline stomatitis for a complete discussion of the disease, treatment options and advice on a proactive approach to managing your kitty's condition.
If your cat has IBD: I recommend my video and article on inflammatory bowel disease in pets, and also "Feline IBD: The Most Common Cause of Vomiting and Diarrhea in Cats."
Polycystic Kidney Disease
Polycystic kidney disease (PKD) is caused by a specific defective gene, and there's a DNA test available to check for it. According to Bell, the gene is present in 6 percent of cats worldwide, and 38 percent of Persian kitties. It is also prevalent in Himalayans and other Persian-type breeds.
The age range for kidney failure in PKD cats is 4 to 10 years, with 7 years as the average. Some kitties with the gene are lucky in that they develop just a few cysts and are able to maintain normal kidney function.
If your cat has polycystic kidney disease: The treatment is the same as for any form of chronic kidney disease, and includes controlling uremia (the buildup of nitrogenous waste products in the blood), delaying the progression of the disease and maintaining the cat's quality of life.
Treatment involves fluid therapy (which many cat parents learn to administer at home), a diet high in excellent-quality protein and lower than normal amounts of sodium and phosphorous and unlimited access to fresh drinking water.
Vitamins and minerals can sometimes be beneficial. I often add a variety of the B-vitamins to a cat's sub-Q (subcutaneous) fluids. B-vitamins can help with anemia, improve a cat's overall feeling of well-being and help with nausea. I also use a probiotic specially formulated for kidney support called Azodyl.
Improving the quality of your cat's diet to include excellent-quality, highly digestible human-grade protein is critical. A few companies specialize in offering fresh kidney-friendly diets.
Standard Process Feline Renal Support can be beneficial as well, along with phosphorous binders and sodium bicarbonate, if appropriate. Your veterinarian will help you decide if these are indicated based on your pet's specific situation. Making kitty's environment as stress-free as possible is also very important.
Hypertrophic cardiomyopathy (HCM) is the most common type of heart disease seen in cats, and it can be inherited or acquired. According to Bell, a gene mutation linked to the condition occurs in 33 percent of Maine Coon cats, and can cause heart failure or sudden death in kitties from 6 months of age to 7 years.
In addition, 20 percent of Ragdoll cats carry a different mutation in the same gene that causes HCM. A genetic test is available to check for both mutations in Maine Coons and Ragdolls. HCM also occurs, typically around midlife, in individual cats of the two breeds who don't carry the gene mutation, as well as in many other kitties.
If your cat has hypertrophic cardiomyopathy: I've successfully treated many cats with this disorder using a combination of high doses of ubiquinol and omega-3 fatty acids, as well as certain amino acids, including taurine, L-arginine and acetyl L-carnitine. I also use heart glandulars and herbs, including hawthorn.
Because amino acid deficiency can fuel HCM, I strongly recommend feeding your cat a human-grade, meat-based diet, and eliminating all fillers such as grains and unnecessary carbs. I believe the carbohydrates found in most processed cat foods offset the amount of protein cats need, making them a significant nutritional contributing factor to feline heart disease.
I also think we've underestimated the role of vitamin D in companion animal medicine, and its role in heart disease, as well. Identifying and treating vitamin D deficiency is an important step in reducing diet-related cardiovascular stress.
The amount of taurine, carnitine and CoQ10 found naturally in unprocessed meat is critically important to feline heart health. These vital nutrients are not found in adequate quantities in most dry foods, and processing further diminishes their bioavailability. This is another reason I recommend starch-free foods (no grains or potatoes) for cats.
If you feed dry or canned food, I recommend you supplement your pet's diet with CoQ10 in the form of ubiquinol, as well as additional marine sources of omega-3 fatty acids (krill oil), especially if you have a cat that may be predisposed to cardiovascular disease. Supplying your pet with extra CoQ10 (the reduced form) can insure she has the quantity her body needs to maintain a healthy heart muscle.
A Final Word About Nutrition and Your Cat's Genetic Destiny
Nutrigenomics is an emerging scientific concept that holds that the nutrition we need as individuals (both humans and animals) depends on our genetic makeup. Our genes and the expression of our genes are controlled by individual nutrients, which means we need personalized, individualized functional nutrition.
It's important to understand how the nutrients we feed our pets will affect their genes, and therefore, their health and longevity. And in fact, if we know which nutrients are essential for individual pets (and people), we can impact longevity, reduce the risk of chronic disease and heal from illness much more rapidly.
Nutrigenomics studies the effect of nutrition on the genome. The genome is everything to do with the body — how it functions metabolically and genetically. The genes are only a small part of the genome, about 2 percent. The other 98 percent has nothing to do with the genes, but with how the body controls what our genes do.
Every individual has a unique molecular dietary signature that determines which nutrients that individual should eat in order to thrive. As veterinarians and pet parents, we can exert some control. For example, if your cat is a breed genetically predisposed to a certain health problem, through nutrition we can suppress certain genes so they don't express themselves, or encourage other genes to do the opposite.