GENETICS

Cat genetics are fascinating, especially when it comes to coat color, white spotting, dilution, and eye color. Understanding the role of white spotting (SS, Ss, ss) and the dilution gene (D/d) can help predict kittens’ colors and patterns, whether you are breeding vans, bi-colors, or planning for cream and blue dilute offspring. This information is also incredibly helpful if you’re looking for a specific color kitten, since knowing the genetics behind a pairing lets you understand what colors a breeder may realistically produce. Many people also think there is a separate “blue eye carrier” gene, but in truth, blue eyes in Exotic Shorthairs are tied directly to the white spotting gene.

The Dilution Gene

  • Think of this as the intensity switch for coat color.

    • D = Dense (dominant): Keeps colors rich and dark, like black, red, chocolate, or cinnamon.

    • d = dilute (recessive): Softens colors, turning them into lighter shades like blue, cream, lilac, or fawn.

    Combinations:

    • DD → Always dense. Kittens won’t be dilute.

    • Dd → Dense but carries dilute. Can produce dilute kittens if paired with another carrier.

    • dd → Dilute cat. All kittens will get at least one dilute gene.

The White Spotting Gene

  • SS = High white, van, harlequin.

  • Ss = Bi-color.

  • ss = Solid (no white).

👉 Eye color connection: Blue and odd eyes are not a separate gene. They are directly tied to the white spotting gene.

  • When pigment cells are blocked from reaching the iris (same way they’re blocked from coat areas), the eye can stay blue.

  • That’s why you only see odd/blue eyes in high-white Exotics (SS, sometimes Ss with a lot of white).

  • There is no such thing as a true “blue eye carrier” — what you’re really carrying is the white spotting gene.

Note: The genetics we’ve outlined are specific to our cattery and breeding cats. We’re only talking about blue eyes being linked to the white spotting gene in Exotics like Wally. This does not include Himalayans or other breeds, which inherit their blue eyes through completely different genetic pathways.

The Tabby Gene  

This gene decides whether a cat shows tabby stripes or a solid spots.

  • A = Agouti (dominant): turns on tabby, revealing stripes, swirls, spots, or ticking.

  • a = Non-agouti (recessive): turns off tabby, making the coat appear solid.

Combinations:

  • AA or Aa → Tabby cat.

  • aa → Solid color spots. 

 

  • Red + Tabby → Red Tabby

  • Cream + Tabby (dilute red) → Cream Tabby

  • Black + Tabby  → Brown Tabby

  • Black + Tabby + Dilute → Blue Tabby

Our Likely Litter Outcomes

 

Wally (SS, D/d, a/a) × Miss Bojangles (Ss, D/d, A/a)

All Kittens

  • White spotting: ~50% high white, ~50% bi-color.

  • Dilution: ~25% dilute, ~75% dense.

  • Tabby probability: In any color you can except ~50% brown tabby, torbie, or red/cream tabby, ~50% solid color spots no tabby.

  • If a kitten is Van you can expect:

    • ~20–30% may develop odd or blue eyes.

    • ~70–80% will develop gold to copper eyes.

 

Female Kittens will all have a varying degree of white and 1 to 2 colors

  • Red/Black Calicos : ~37.5%

  • Blue/Cream Calico: 12.5%

  • Black/Red Torti: ~18.75%

  • Blue/Cream Torti: ~6.25%

  • Black bi-color: ~6.25%

  • Red bi-color: ~6.25%
  • Blue bi-color: ~6.25%
  • Cream bi-color: ~6.25%

 

Male Kittens will all have a varying degree of white and 1 other color:

  • Black: ~25%

  • Blue: ~25%

  • Red: ~25%

  • Cream: ~25%

Summary: Vans and bi-colors only. About one out of every four kittens could be dilute, the rest dense. For any color 50% will show some type of tabby pattern. Odd/blue eyes possible in Van kittens.

👉 These percentages are just an estimate. In practice, you might see all dilutes in a litter, all vans, or all bi-colors — genetics roll the dice each time.