EXP, F1, F2,

 

EXP, F1, F2, and so on are terms used to describe different generations in breeding. For example, the trait of being hairless in Sphynx cats is recessive, meaning it’s less dominant than having fur. When a furred female cat (queen) is bred with a hairless male (stud), all the kittens will have fur. The mother can only pass on a fur allele, while the father can only pass on a bald allele. 

 

This group of kittens is known as the experimental (EXP) generation. Each kitten will have fur but will carry one gene for hairlessness.

 

If a furred kitten from the EXE generation is then mated with a Sphynx male, the furred kitten will pass on the fur gene to about half of the kittens and the bald gene to the other half. The kittens that receive the fur gene will have fur but will still carry the hairless gene from their father. The other kittens that inherit the bald gene from both parents will be hairless. This group is called the F1 generation, which includes both furred and hairless kittens.

 

If a hairless kitten from the F1 generation is bred with another hairless cat, all the kittens will be hairless too, as they can only pass on the bald gene. This is referred to as the F2 generation.

 

Through selective breeding, hairless kittens tend to become progressively bald with each generation. 

 

If the original furred mother is bred with a pure hairless Sphynx, all the kittens will carry the bald gene.

 

Dilution

 

Cats primarily exhibit two dominant colours: black and red. However, these colours can be modified by dilution, leading to variations such as blue, caramel, chocolate, lilac, cinnamon, or fawn from black, and cream from red.

 

To determine if a black or red cat carries the dilution gene, DNA testing must be performed. Additionally, examining the cat's pedigree can provide insights into potential inherited traits. Observing the kittens produced by the parents can also reveal which traits they carry.

 

If both parents are homozygous for either black or red, they cannot produce kittens with diluted colours. This can only happen if both parents carry the recessive dilution gene and pass it to their offspring. Conversely, if both parents have diluted colours, they will not produce kittens with dominant colours, as the dominant trait will manifest if at least one gene for it is present in the genotype.

 

 

Tabby 

 

Tabby cats are known for their distinctive stripes, and there are several recognised patterns:

 

1. **Mackerel Tabby**: Characterised by thin, parallel stripes that resemble a tiger’s markings.

2. Classic Tabby**: Features bold, swirling patterns on the sides, similar to a marbled cake. In the UK, this is often referred to as “blotched."

3. **Spotted Tabby**: This pattern displays spots on the sides, which can vary in size and may resemble the interrupted lines of a mackerel tabby.

4. **Ticked Tabby**: Also known as Abyssinian or Agouti, these cats have stripes only on their faces, with no stripes on their bodies.

 

Tabby patterns can appear in any colour combination. To identify the specific colour of your tabby cat, look at the colour of the stripes and the tip of the tail; these areas will typically be darker than the background colour. In cream or red kittens, it can sometimes be difficult to determine if they are tabby, and young kittens may display "ghost markings" that fade as they grow.

 

Understanding a bit of genetics can be very helpful. The tabby pattern is dominant, meaning a cat only needs one allele for tabby to exhibit the pattern. Therefore, any kitten with at least one tabby parent can be a tabby. However, a kitten from two non-tabby parents cannot be tabby at all.

 

It's important to note that having two tabby parents does not guarantee tabby kittens, as both parents might carry the non-tabby (solid or self) gene. Since non-agouti cats (self or solid) only express their colour when melanine is involved, there is often no visible difference between cream/red kittens and cream tabby/red tabby kittens.

 

 

White

 

White is a dominant colour in cats, meaning it can cover up other colours beneath it. This dominance is referred to as episthatic, as it suppresses all other colours. A white cat with red eyes is known as albino, which means it has no pigment at all. There is also a Siamese variant called the Foreign White, which has blue eyes.

 

Many white cats, regardless of eye colour, are often deaf. The BAER test can be used to determine if a cat is deaf. It's advisable to exclude deaf cats from breeding programs, and two white cats should not be bred together due to the increased risk of producing deaf kittens. Sometimes, a cat may only be deaf in one ear.

 

Similar to tabby patterns and dominant colours like red or black, a white cat must have at least one white parent. Pure white cats with two alleles for the white gene are rare because breeding two white cats is generally avoided. Most white cats carry a gene for another colour inherited from one of their parents, which means it is possible for a white cat to have a black kitten. Statistically, about half of the kittens from a white cat will also be white.

 

The eye colour of a white cat can be blue, orange, or even "odd," where each eye is a different colour. Sometimes, white kittens are born with black or grey spots or stripes on their heads, which typically fade as they mature.

 

Breeders often make mistakes with white kittens, as all pointed kittens are born white and develop darker markings over time. Therefore, it's essential to remember that two non-white parents cannot produce a white kitten.

 

In Sphynx cats, it can be challenging to distinguish between white, cream, or cream and white kittens. Understanding genetics and referring to pedigrees can be very helpful in these cases.

 

Cats with white markings are often described with terms that reflect their specific patterns:

- **Mitted**: White paws.

- **Locket**: A small white spot on the chest.

- **Buttons**: White spots on the belly.

- **Bi-color**: Half of the cat's coat is white.

- **Harlequin**: Mostly white with several large coloured patches.

- **Van**: Almost entirely white, with coloured markings only on the head and tail.

• Cats with white paws, chest, and belly may also be called "tuxedo," which can include some white on the face.

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Tortie.

This is what we call a cat with the colours black and red (or in the diluted version blue and cream, e.g.). These colours run into each other. The gene responsible for red (the O-gene) is located on the X-chromosome, so only females can be tortie. Tortie is also called tortoise.
When the different colours are easily discerned, and appear in larger patches, with white, the cat’s colour is called “Tri-colour” or “Calico”. These three-coloured cats are also always females. If and when a male tortie or tri-colour is born, it is usually sterile.

Also interesting: if a red or cream stud is mated to a queen with a different colour from red or cream, all female kittens will always be torties.

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Colour Points

 

Siamese, Tonkinese, and Burmese cats are often referred to in terms of color, but they are actually patterns influenced by a series of alleles that affect albinism to varying degrees. 

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- Siamese cats (cs/cs) are primarily white with darker markings on their extremities: the nose, ears, tail, and paws. 

- Tonkinese cats(cs/cb) are a shade darker than Siamese, while

 

-Burmese cats (cb/cb) are the darkest among the three, all featuring darker points on their bodies. The temperature plays a significant role in their colouration;

 

Siamese cats allowed outdoors will develop a darker body than those kept indoors. This is because Siamese kittens are born white; in utero, their extremities are warm like the rest of their bodies, but upon birth, the extremities cool slightly, leading to the characteristic coloration.

 

Siamese cats are sometimes called Colour Points, Tonkinese cats are referred to as Minks, and Burmese cats are known as Sepia. These patterns can occur in various colours. For example, a Red Point is a red cat with Siamese characteristics, while a Chocolate Mink is a brown Tonkinese, and a Blue Sepia is a grey Burmese.

 

Identifying whether a kitten is Siamese, Tonkinese, or Burmese can be done through a couple of key traits. Siamese kittens are born milky white and develop their colour later, making this more apparent in dominant colours compared to diluted ones. In contrast, Minks and Sepias are born with colour that will darken as they grow.

 

Eye colour is another distinguishing factor. All kittens start with blue eyes, similar to human babies, but by around 10 weeks, their eye colour begins to change.

Siamese cats have blue eyes, not DBE Eyed Colour

Tonkinese cats have blue-green (aqua) eyes, and

Burmese cats have yellow eyes.

 

The distinction between blue and aqua can be subtle and may take several months to become clear, which poses a challenge for breeders creating pedigrees.

 

In terms of genetics, a Siamese cat requires two genes for the Siamese pattern, and the same applies to Burmese cats. If a Siamese cat is bred with a Burmese cat, the offspring will be Tonkinese. Two Siamese parents can only produce Siamese kittens, as can two Burmese parents. However, kittens from two Tonkinese parents can be Siamese, Burmese, or Tonkinese, depending on the genes inherited.

 

A cat cannot be a “carrier” of the Tonkinese gene without exhibiting either Siamese or Burmese traits, as both genes must be present. A kitten from a Tonkinese parent can carry the gene for either Siamese or Burmese. Cats with no pointed gene cannot produce pointed or Mink kittens but can produce Siamese or Sepia kittens if paired with the right partner. A kitten carrying only one of the genes (Siamese or Sepia) will not visibly display this trait but can potentially produce Siamese, Mink, or Sepia offspring when paired correctly.

 

Examining a cat’s pedigree can provide insights into the genes that may or may not be passed on. It becomes more complex when a cat is a carrier for Siamese or Burmese traits without visibly showing those characteristics, especially if this trait has been passed down through generations without appearing. Importantly, two non-pointed parents can produce pointed kittens if they both carry and pass on the gene, as this is a recessive trait.

 

As kittens mature, the coloration of their nose leather and paw pads can also hint at their future coat colour.