Maine Coon Genetics

The genetics of every cat breed leads to their own distinctive physical characteristics, and Maine Coon genetics are no different.

Genetics impact everything from a cat’s temperament to its size, colors, and other physical characteristics.

In general, Maine Coon genetics lead to large, sturdy cats with tufted ears and broad chests. Their coat is long and silky, and they come in every available coat color, barring patterns and colors that are only specific to particular cat breeds (such as color points).

This article will cover which aspects of a Maine Coon are genetically inherited, as well as ways you can screen your own feline to discover its genetic history.

Maine Coon Genetics

The Maine Coon cat first originated in Maine and is the oldest longhaired cat breed in America.

The breed originated naturally, and as such, there is little information available about its true history.

Maine Coon cats were recognized for their sturdiness and good mousing ability, as well as their gentle disposition.

Over time, people began to prize the Maine Coon for its stupendous size. Nowadays, they can range anywhere from 8 to 25 pounds!

In general, a Maine Coon’s size is affected greatly by the genetics of its parents. However, there is no completely accurate way to tell exactly what size a Maine Coon will grow up to be.

The size of a Maine Coon depends on its inherited dominant traits.

Even if both parents of a kitten are large, there is a chance the kitten may inherit two recessive traits, making it smaller than its parents.

Still, over time, breeders have been able to produce larger and larger litters of kittens, and the average size of a Maine Coon has only increased with time.

Why A Maine Coons Genetics Impact Their Color And Pattern

Some cat breeds only come in a small variety of colors and coat patterns.

Maine Coons, however, come in a stunning variety of colors, as well as multiple different patterns.

Maine Coon Patterns

Here are the patterns that Maine Coons are known to have:

1. Solid

Solid Maine Coons have only one coat color that is completely unbroken and unmarked.

2. Smoke

A Maine Coon whose coat is smoky comes in one solid coat color, but the color on the base of the hair fades slightly so that the undercoat is lighter.

3. Tabby

The most characteristic coat pattern for a Maine Coon is tabby. A tabby cat has darker stripes over its body.

The three different tabby patterns that a Maine Coon can have are:

  • Classic
  • Mackerel
  • Patched

4. Tabby And White

This is a pattern where a Maine Coon is solidly tabby throughout its body except for its chest and paws, which are white.

5. Tortoiseshell

Present only in female Maine Coons who receive both red and black coloration from her parents, a Tortoiseshell has a base color of black with red and cream patches.

6. Shaded

This pattern describes a cat whose coat is one solid color with a darker version of that color present throughout the coat, creating a lovely shaded effect.

7. Shaded And White

Like the tabby and white pattern, this is where a Maine Coon comes with a shaded pattern as well as white on its chest and paws.

Maine Coon Colors

While some cat breeds come in only a select few distinctive colors, Maine Coons can come in virtually every color possible.

In total, there are about 75 different possible coat colors.

However, the three main colors that a Maine Coon’s coat can have are red, black, and white.

1. Black

The fur of a black Maine Coon contains what is called “eumelanin,” which can be diluted through genetics to appear in many different shades and hues.

If a black cat breeds with a diluted cat, (which appears paler in color) they may have kittens with diluted black coats.

This black dilute is also called “blue,” because it appears as a sort of bluish-gray.

Black tabbies also appear brown because, while their stripes are black, the rest of their coat is lighter in color and no longer appears to be black.

2. Red

Red Maine Coons can also be diluted so that their coat appears cream in color.

Red fur can look very different depending on the cat, ranging from bright orange to a ruddy russet.

3. White

White fur is fur that lacks pigment.

While most Maine Coons do not come in solid white, there are many cats in this breed who have white patches.


Overall, a Maine Coon’s coat color depends entirely on genetics.

These three basic colors (black, red, and white) can be diluted or combined to produce a crazy total of 75 different possible coat colors.

Why Maine Coon Genetics Impact Eye Color

Eye color is also determined by a cat’s genetics, but the genes responsible for this cannot be seen at the surface.

Even if both parents have the same eye color, this does not inherently mean that their kittens will also have that same eye color.

Rather, eye color is determined by the amount of melanin present in the cat’s iris. This means that two green-eyed cats could very well have a kitten with golden eyes.

All kittens are born with very little pigmentation, so their eyes are blue for the first few weeks of their lives.

As they grow older, however, they produce more melanin, which can result in green, gold, and copper eye colors, as well as many other hues.

Unfortunately, there is no real way to determine what a litter’s eye colors will be.

Maine Coon Genetic Eye Problems

Certain cat breeds can be prone to specific illnesses or health issues.

When it comes to Maine Coon cats, they are unlikely to develop eye-related issues. Some kittens may be near-sighted or far-sighted, but this is rare.

In general, Maine Coons are no more susceptible to genetic eye problems than any other cat breed.

Polydactyl Maine Coon Cat Genetics

Some cats may be polydactyl, meaning they have more than the usual number of toes on one or multiple feet.

Polydactyly used to be quite common in Maine Coon cats, as they evolved in snowy conditions where it was useful to have large, well-insulated feet.

Polydactyly is caused by a certain gene which, because it is dominant, is highly likely to be inherited by the kittens of a polydactyl parent.

However, most breeders managed to weed out this genetic trait, and most Maine Coons today are not polydactyl.

Maine Coon Genetic Diseases

As with any other breed, Maine Coons can be more susceptible to certain inherited diseases.

The most common Maine Coon cat diseases are:

  • Spinal Muscular Atrophy
  • Hip Dysplasia
  • Hypertrophic Cardiomyopathy

1. Spinal Muscular Atrophy

Spinal muscular atrophy is a disease that atrophies the motor neurons of a cat’s spine, which eventually results in an uneven gait and posture.

Thankfully, it is painless to the afflicted cat and does not result in death.

This disease is caused by a recessive gene. If a cat has one copy of the gene which carries spinal muscular atrophy, it will not have the disease, but it will be a carrier.

If it receives a copy of the gene from both of its parents, then the cat will, unfortunately, be affected by the disease, which usually occurs within a few months after being born.

2. Hip Dysplasia

Hip dysplasia is another common disorder found in Maine Coon cats.

The average Maine Coon has about a 20% chance of contracting the disorder, which results in abnormal hip development.

While there isn’t as much known about this disorder in cats, it is likely a genetically inherited disorder.

Finally, Maine Coons are also susceptible to hypertrophic cardiomyopathy. In most cases, this condition is inherited through a genetic mutation.

According to UC Davis Veterinary Genetics Laboratory, if the cat has one copy of this mutation, it is 1.8 times more likely to develop the condition.

If the cat receives two copies of this mutation, it is 18 times more likely to develop the condition.

Why A Maine Coons Genetics Impact Their Offspring

The genetics of a Maine Coon cat greatly affect the coat colors of their offspring. Certain coat colors are only possible if one or both parents also have that coat color.

Black coloration is the result of the gene called eumelanin, and at least one parent must have that gene present in order to produce kittens who also have the gene.

The red coloration comes from a gene known as pheomelanin. Because this gene is sex-linked, red kittens will only occur if the parents of the same sex as them are also red.

Because white coat colors are the absence of both eumelanin and pheomelanin, a white coat must be the result of at least one parent also having a white coat.

To produce a Maine Coon with white, you must breed it with at least one parent whose coat also contains white.

Tortoiseshell cats, which contain both red and black, can only occur in female kittens whose mother also carries the color red.

Furthermore, at least one of the parents must carry the color black, as well.

This means that a tortoiseshell kitten can occur if the mother is red and the father is black, or if the mother is tortoiseshell and the father is any other color.

Maine Coon Genetic Testing

You may want to get a genetic test for your cat to see what conditions it may be susceptible to inheriting.

Furthermore, genetic tests are useful for breeders if they are looking to produce or avoid specific traits. Genetic tests can show which inherited coat colors and patterns a cat may have.

Breeders also like to screen for diseases such as spinal muscular atrophy, hip dysplasia, and hypertrophic cardiomyopathy.

Some common places to get tests for your own cat is through genomia or MyCatDNA. Test kits cost anywhere from $30 to $100, depending on what you are screening for.

The accuracy of these tests is generally estimated to be over 90%.


Learning about Maine Coon genetics is valuable if you are interested in breeding your own cats, or if you simply know which characteristics to expect when adopting your own kitten.

By learning about how genetics affect your cat’s coat color, coat pattern, eye color, and inherited diseases, you will have a much better idea of why your Maine Coons look the way it does, as well as why each Maine Coon is so different.

Maine Coon Central

Hello! My name is Katrina Stewardson, and I’m a CRAZY CAT LADY! I've been in love with the Maine Coon cat breed ever since we welcomed an adorable male Maine Coon kitten into our home 10 years ago. We called him 'Pippin', but he also goes by the name ‘Pipsteroo’! Our enormous, kind-hearted cat genuinely thinks he's a dog and has convinced me that cats are Man's True Best Friend! UPDATE: We recently adopted two 4-year-old male Maine Coon cats. They are named Mika and Bali.

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