Cat Genetics for Dummies
Picture genes as the blueprints that determine why Mittens has those striking stripes while Whiskers is a solid color. They're made up of DNA and are passed down from parents to offspring. Here at Wingbeats, we aim to present this complicated concept in a digestible, simple manner that is both accessible and engaging. Don't worry, I have a calculator that can help - you're not in this alone! That being said, our Discord is always happy to support genetic conversations. However, a basic understanding of genes goes a long way. This has been written with the expectation that you have no idea what genes even are, so please don't worry about having legacy knowledge!
Now, let's break it down. Genes come in two flavors: recessive and dominant. The recessive genes are like those bashful wallflowers at a party. They'll only bust a move if there's a matching pair hanging out together. If a dominant gene – the life of the genetic party – crashes in, the recessive one shies away. So, both parents need to rock the recessive gene for it to strut its stuff. Even if a dominant gene is paired with a recessive gene, the dominant trait still shows up. Each parent passes one gene to their kittens.
You're welcome to test each option out with Sparrow Garden's Cat Coat Calculator, as it will be what litters on Wingbeats will use to calculate. However, in this post I will make every gene easy to understand. You do not need any additional gene knowledge besides what is in this post to create Wingbeats characters!
I also highly recommend checking out Sparrow Garden's Cat Color Glossary as it provides a good visual!
Do you need to read this? Well, no! You're welcome to skim or read it all, that's entirely up to you! Here is a TL;DR:
(wip)
Fur Length - Good Introduction to Genetic Beginners
Let's use visual examples to introduce you to the concept! I will be using fur length as my example for today, however I will break down the rest of the genes later in my post. I will be using a capital L to represent the dominant gene (short-furred) and a lowercase l to represent the recessive gene (long-furred). Again, each parent passes one gene to their kittens.
Short fur: LL
Long fur: ll
Short fur, but carries long: Ll
Let's consider an instance where two short-furred warriors (LL) had a litter of kits together! The parents were not carrying the recessive long-furred gene, so their kittens would only carry the dominant short-furred gene (LL) and there would be no possibility for a long-furred kitten to occur in this litter. They do not carry the recessive gene (long-furred).
Let's say a similar instance - where two long-furred warriors had a litter of kittens! The parents are carrying only the recessive gene (ll) and are representing long-furred as the result. Their kittens would only carry the recessive long-furred gene and there would be no possibility for a short-furred kitten to occur in this litter. They only carry the recessive gene (long-furred).
Here's where things get interesting! What if a short-furred (ll) and a long-furred warrior (LL) had a litter of kittens? Because the short-furred parent is only carrying the dominant gene, and the long-furred parent is only carrying the recessive gene, their kittens would appear short-furred but carry the long-furred gene recessively (Ll). This means if their kitten were to grow up and have kits with another carrier of the long-furred gene (l), it would potentially produce long-furred kittens. Remember, each parent passes one gene to their kittens and the short-furred parent only has the dominant gene to give.
In the instance a carrier of both genes but representing short-furred (Ll) and a long-furred (ll) warrior had kittens together, the kittens will always inherit a long-furred gene from their long-furred parent. However, the litter can be a mix of only carrying the gene, or representing it! This is up to the roleplayer when it is a toss up like this. It depends entirely on your preferences.
This is where genetics gets the most exciting! When two short-furred cats who are carrying the recessive gene (Ll) have kittens, the kittens have a wide realm of possibilities as they inherit one gene from each parent. Again, this is up to the individual roleplayer. You're welcome to choose any one of these!
Fur Length Parameters on the Cat Coat Calculator:
Long: long-furred, carries only the recessive trait (ll)
Short, carries long: short-furred, carries both traits (Ll)
Short: short-furred, only carries dominant traits (LL)
Dilution
The dilution gene affects the intensity of the cat's coat color. It lightens the color - causing it to have softer, pastel-like hues compared to its non-dilute counterparts. Dilute colors are commonly seen in breeds you may already recognize - like the Siamese, Burmese, and Ragdoll! It, much like long fur, is a recessive gene. This means a cat must inherit two copies of the dilution gene for their pelt to show the diluted color.
I will be using a capital D to represent the dominant gene (non-dilute) and a lowercase d to represent the recessive gene (dilute). Again, each parent passes one gene to their kittens. It works very similarly (or identically) to long fur! However, I will explain it anyway.
Non-dilute: DD
Dilute: dd
Non-dilute, but carries dilute: Dd
Much like the long fur recessive gene, if two non-dilute (DD) warriors were to have a litter of kits, they would also be non-dilute. The parents were not carrying the recessive dilute gene, so their kittens would only carry the dominant non-dilute gene (DD) and there would be no possibility for a dilute kitten to occur in this litter. They do not carry the recessive gene (dilute).
Let's say a similar instance - where two dilute (dd) warriors had a litter of kittens! The parents are carrying only the recessive gene (dd) and are representing diluted pelt colors as the result. Their kittens would only carry the recessive diluted gene as there are no dominant genes to be given by their parents. There would be no possibility for a non-dilute kitten to occur in this litter. They only carry the recessive gene (dilute).
What if a non-dilute (DD) and a dilute warrior (dd) had a litter of kittens? Because the non-dilute parent is only carrying the dominant gene, and the dilute parent is only carrying the recessive gene, their kittens would appear non-dilute but carry the dilute gene recessively (Dd). This means if their kitten were to grow up and have kits with another carrier of the dilute gene (d), it would potentially produce dilute kittens. Remember, each parent passes one gene to their kittens and the non-dilute parent only has the dominant gene to give.
In the instance a carrier of both genes but representing non-dilute (Dd) and a dilute (dd) warrior had kittens together, the kittens will always inherit a dilute gene from their long-furred parent. However, the litter can be a mix of only carrying the gene, or representing it! This is up to the roleplayer when it is a toss up like this. It depends entirely on your preferences.
This is where genetics gets the most exciting! When two non-dilute cats who are carrying the recessive gene (Dd) have kittens, the kittens have a wide realm of possibilities as they inherit one gene from each parent. Again, this is up to the individual roleplayer. You're welcome to choose any one of these!
List of most non-dilute pelt colors v.s.their dilute equivalents
| Non-dilute Color | Dilute Equivalent |
|---|---|
Black | Blue (grey) |
Red/Orange | Cream |
Chocolate | Lilac |
Cinnamon | Fawn |
Tortoiseshell (black/orange) | Tortoiseshell (blue/cream) |
Tortoiseshell (chocolate/cinnamon) | Tortoiseshell (lavender) |
Dilution Parameters on the Cat Coat Calculator:
Non-dilute: non-diluted, carries only dominant trait (DD)
Non-dilute, carrier: non-diluted, carries both traits (Dd)
Dilute: dilute, only carries recessive trait (dd)
White - markings, pelt color
The white gene plays a significant role in determining the extent of white markings, and yes - that does include white pelts! While 'white' isn't a distinct coat color, it does represent a significant presence of white markings. These markings can vary greatly, from small patches to entirely white coats.
Unlike other genes we've covered like dilution and fur length, this is a dominant gene. It masks other coat colors when present. If you are familiar with piebald or albinism mutations on Lioden™, the white gene in cats works similarly in that the pelt color and markings still exist, yet there is a white "layer" overlaying it. Think of the white gene as a painter's brush, adding splashes of white to the canvas of a cat's coat, influenced by other genetic factors. A cat that appears pure white can have a completely different genetic makeup compared to another white cat. This difference means they can produce entirely different kittens, as every gene is masked "beneath" their white coats.
There are two genes at play here. The dominant white gene (WD) and the dominant white spotting gene (WS). They work together to determine the amount of white. But... What's the difference?
The dominant white gene (WD) leads to a fully white coat, even if they only have one copy of this gene - unlike fur length, which needs two copies to be long.
The dominant white spotting gene (WS) leads to the formation of white spots, patches, or areas. The extent of this white spotting can vary. Again, it is dominant, so the cat only needs one copy of this to lead to white formation!
Because these genes are dominant, they are represented by uppercase letters unlike fur length.
| Sparrow's Garden Calculator Parameter | What Does the Cat Look Like? | Represented By |
|---|---|---|
No white | This cat has a fully colored coat with no white markings. | wsws |
0-50% white | This cat has some white patches. This could be white paws, a white chest, a white tail tip - you get the point! | WSws |
50-100% white | This cat has extensive white patches that take up at least half of their body. Think of tuxedo cats! | WSWS |
Dominant white, carries non-white | This cat is entirely white! It carries non-white genetics. | WDws |
Dominant white, carries white spotting | This cat is entirely white! It carries white spotting genetics. | WDWS |
Dominant white | This cat is entirely white! | WDWD |
Please utilize the Sparrow Garden Calculator to calculate the resulting white from pairings! With two genes working together, it can get complicated. Sparrow Garden offers a simple, straightforward way to calculate possibilities. However, please note if you're attempting it manually - that white dominance or white spotting will present itself in a cat even if there's only one copy of the gene and each parent gives a copy of one of their genes!
Eumelanin
Eumelanin is a pigment that gives dark colors to the base color of a cat's fur. It's responsible for shades like black, dark brown, and light brown. If a cat has a lot of eumelanin, the fur looks darker - like black. If there's less eumelanin, the fur looks lighter.
Black is the dominant form of eumelanin. A cat will only need a single copy of the black gene to appear black. Chocolate is recessive to black, and a cat will need two copies to appear chocolate. Cinnamon is recessive to both and needs two copies to appear cinnamon.
Black > Chocolate > Cinnamon
Black: B
Chocolate: b
Cinnamon: bl
Eumelanin Parameters on the Cat Coat Calculator:
Black: The cat is black and does not carry chocolate or cinnamon. BB
Black, carries chocolate: The cat is black but carries a hidden chocolate gene. Bb
Black, carries cinnamon: The cat is black but carries one hidden cinnamon gene. Bbl
Chocolate: The cat is chocolate. bb
Chocolate, carries cinnamon: The cat is chocolate but carries a hidden cinnamon gene. bbl
Cinnamon: The cat is cinnamon because it inherited two copies of the cinnamon gene. blbl
Sex-linked Red
"Sex-linked" means that the gene in question is located on the sex chromosomes, which are the chromosomes that determine whether the cat is male or female. In cats, females have two X chromosomes (XX) and males have one X and Y chromosome. A sex-linked gene is on the X chromosome. The sex-linked red gene controls the red color of the base color of a cat's fur. The sex-linked red gene is X-linked and dominant when it is present. So, it can show up in both males and females, but the way it’s inherited differs between them because of their sex chromosomes.
You cannot carry it recessively in the same way you can with other genes (like chocolate or cinnamon). This is because the red gene is dominant on the X chromosome.
Males only have one X chromosome. So if they inherit the red gene (XO), they will have red fur. If they don't inherit this gene, they will have non-red fur like black, brown, etc.
Females, on the other hand, are a little tricky! They have two X chromosomes. They need two red genes (XOXO) to show solid red fur. If they only inherit one, they will be tortoiseshell - a mix of red and non-red colors. If they have no red gene at all, they will be non-red. This is why orange female cats are rare. All calicos are just tortoiseshells with white.
This is why males who are tortoiseshell are unable to reproduce, as they have an extra chromosome. Tortoiseshell males typically have a condition called Klinefelter syndrome, where they have two X chromosomes and one Y chromosome (XXY). The XXY chromosomal configuration is not typical for male cats, and it leads to fertility issues. Males with Klinefelter syndrome generally have impaired spermatogenesis (the process of sperm production), which means they are usually infertile. The extra X chromosome disrupts the normal development of reproductive cells (sperm), causing infertility in tortoiseshell males. Wingbeats respects this, and male tortoiseshells will be infertile in our roleplay setting. It is highly recommended to research this syndrome if you decide to play a male tortoiseshell.
Sex-linked Red Parameters on the Cat Coat Calculator:
Red: Carries sex-linked red. (Remember, this cat will be tortoiseshell or orange)
Not Red: Does not carry sex-linked red.
Tabby or Solid
In cats, the tabby pattern is dominant over being a solid color. This means a cat who carries the tabby gene will show the tabby color unless it inherits a gene that suppresses it.
A solid-colored cat has inherited two copies of the recessive "t" allele for a solid coat. These cats do not show any tabby markings, even though they carry the tabby pattern gene in their genetics. A cat described as "solid, carries tabby" has one copy of the dominant tabby gene (T) and one copy of the recessive solid gene (t). These cats appear solid, but because they carry the tabby gene (T), they can pass the tabby gene on to their kittens. A cat described as a "tabby" has at least one copy of the dominant T allele. These cats will display the tabby pattern — either mackerel, classic, spotted, or ticked, depending on the other genetic factors involved.
Solid - solid color (tt)
Solid, carries tabby - solid color, carries tabby that is suppressed (Tt)
Tabby - tabby, shows tabby pattern (TT)
Tabby Pattern
Tabby patterns refer to stripes or spots on a cat's fur. These patterns are caused by a genetic mutation that affects the distribution of pigments in the fur. In Wingbeats, we recognize mackerel, classic, spotted, and ticked patterns. As we covered in the previous section, even if they carry the recessive solid gene, they will still have suppressed tabby patterns. These suppressed patterns can be passed down to their kits.
I highly recommend using the calculator to see how the pattern combinations can show up in your kittens. The actual genetics behind these patterns can get pretty complicated, but our simplified calculator and approach make it much easier to understand and plan for, just to keep things simple and stress-free. 
Classic (#1): The classic tabby pattern has wider, swirled stripes forming patterns like marbling or a butterfly shape on the cat’s shoulders.
Mackerel (#2): Mackerel is usually considered the "classic" tabby pattern, where the cat has thin, parallel stripes that run down its body, like a fishbone.
Spotted (#3): The spotted pattern results in random spots or patches on the cat's body, and it can vary in size.
Ticked (#4): Ticked tabby patterns usually mean the individual hairs are banded with alternating colors. This gives a more "speckled" or "salt-and-pepper" appearance and is often seen in breeds like Abyssinians.
Silver / Smoke
The Silver/Smoke gene is also known as the inhibitor gene (I). It impacts the production of eumelanin (black/brown pigmentation) and sometimes affects pheomelanin (red/orange pigmentation). This gene lightens the base of each individual hair, creating a "silver" or "smoke" effect, depending on the cat's underlying coat pattern.
Dominant gene (I): The inhibitor gene is dominant, so a cat needs only one copy of the I allele to display the silver or smoke effect.
Recessive gene (i): If a cat has two recessive alleles (ii), it will not show the silver/smoke effect.
What does it do? For example, When the cat has a tabby pattern (T), the inhibitor gene creates a silver tabby coat. The tabby stripes, spots, or ticking remain dark, but the background (the lighter parts of the tabby pattern) is silvery white instead of golden or brown. A mackerel tabby with the inhibitor gene will have distinct black stripes on a silvery-white background. When the cat has a solid coat (tt, non-tabby), the inhibitor gene creates a smoke coat. The hair shafts are white at the base and dark at the tips, giving a "smoke-like" effect. A solid black cat with the inhibitor gene will appear dark, but when its fur is parted, you’ll see the white base. Smoke cats often have "ghost markings", which let appear their underlying tabby pattern that we covered in previous sections. The smoke effect - especially when they're shorthair - is sometimes almost invisible if the fur is not parted.
Non-silver (ii) - does not showcase silver or smoke.
Non-silver, carries silver (Ii) - not showing, but could potentially produce silver kittens.
Silver (II) - has sliver/smoke.
Colorpoint
The colorpoint gene (responsible for the pointed pattern in cats, like Siamese and Himalayan cats) is a recessive gene. This means a cat must inherit two copies of the gene (one from each parent) to show the pointed coat pattern. The colorpoint gene is also known as cs (for "colorpoint restriction"). It causes the fur on the cat's body to remain lighter, while the extremities (ears, face, paws, and tail) develop darker pigmentation. This effect happens because the colorpoint gene is temperature-sensitive: warmer areas of the body (like the torso) remain light, and cooler areas (like the extremities) develop darker pigment.
For a cat to display the pointed pattern, it must have two copies of the colorpoint gene (cscs).
If a cat has only one copy of the gene (Ccs), it will not show the pointed pattern but can pass it to its offspring.
The dominant form of the gene (C) produces normal coat coloration (non-pointed).
Now, let's apply it to some kitties!
In this section, we'll apply what we have learnt in this post to real-life cats and stylized designs, and the assumptions we can or should make. Additionally, in this section, we will explore how we can make assumptions about the possibilities of a couple's litter.
To dive further into what "stylization" and "stylized design" mean to our genetics, think of it this way: when you draw or design your Wingbeats cat, you are showing your personal art interpretation. However, in-universe, that same cat would look more like a real, genetically accurate feline. Stylization is completely accepted, as long as the design respects the genetics at play. When drawing your own designs, I ask that everyone include at least one real-life photo reference with their character that presents their coloration, markings, etc.
Let's start with a stylized version of Shimmering Sea, played by uwubers! In the allegiances, Shimmering Sea's description is a cream spotted tabby she-cat with short fur and blue eyes.
From that description and appearance alone, we already can assume the following genes:
dd (Dilute - cream is a dilute orange!)
wsws (No white mentioned)
XOXO (Cream = orange!)
TT (Tabby)
S (Spotted tabby pattern)
However, we're missing a few details. We cannot determine her eumelanin color (black or brown), since sex-linked red effectively "turns off" eumelanin expression. Likewise, we cannot assume any recessive traits - such as long hair, silver/smoke, or colorpoint -unless her parents are known to carry them.
In cases like this, where there's no canonical indication of inherited recessives, we assume the cat does not carry them. This helps preserve the intended rarity of recessive traits within the population. However, this is extremely rare in itself to assume. In most cases, players will know the full genotype, since NPCs are provided with complete genetic information. However, since Shimmering Sea is one of the first cats on Wingbeats - we have to make some assumptions about her parents! We will give her the most dominant traits, making her full genome:
LL dd wsws BB XOXO TT S ii CSCS
She has short hair. She is dilute. She has black eumelanin. She is orange. She has tabby stripes. She has a spotted tabby pattern. She does not showcase silver or smoke. She has no copies of the colorpoint gene. Realistically, we could say she (give or take) looks like the following pretty kitty in the Wingbeats universe!
Hypothetically, let's say that she became mates with a tom and they eventually had kittens. Their players would like to offer these kits up for adoption. This is his genome:
LL Dd WDWS BB xo Tt M Ii CSCS
He has long hair. He is not dilute, but carries a dilute recessive. He is dominant white and carries white spotting. He is black. He is not red. He has tabby stripes but carries solid recessively. He has mackerel stripes. He carries silver/smoke recessively. He does not carry any colorpoint genes.
We can assume from his genome that he is a beautiful long long-haired, white tom. I can guess why she fell in love with him! Underneath his white, he is a long-haired black mackerel tabby. He would likely look something like this:
Okay... Let's plug this into the Sparrow's Garden Calculator!
Kittens will be shorthaired. Toms can be red or cream, or dominant white. Mollies can be tortoiseshell or dilute tortoiseshell, or dominant white. Kittens can be spotted tabby, mackerel tabby, or classic tabby. Those that aren't dominant white will have under 50% white spotting.
We can assume the player's kits from this litter can be:
Shorthair, but could carry long hair recessively. (Ll)
Dilute or nondilute, but carries dilute recessively. (dd or Dd)
All cats can be dominant white, but those who are not dominant white will have under 50% light spotting. (WDws or WSws)
All cats will be black.
Males can be solid orange and females can be tortoiseshell. (XO, xo, or XOxo)
Spotted tabby, mackerel tabby, or classic tabby.
They can carry silver/smoke recessively. (Ii)
I recommend taking their genomes and combining them, and looking to see if you can find a real-life version of that kitty! Doing it personally, I can tell you that my favorite variation is a beautiful dilute tortoiseshell daughter. Anyways... Now you know how to apply genetics to a real-life scenario! Feel free to always reach out if you need help understanding something. No questions are dumb!
I'll catch you next time. 
Citations & Credits
Cat Base by PastelMangoo. This base was not free and was paid for. Examples were made by kieer utilizing them.
Eraser image belongs to pngall.com - under Creative Commons 4.0 BY-NC
All photography of cats (c) to their original owners.