Coat Colour Genetics in British Shorthairs

British Shorthair Coat Colour Genetics: Blue, Lilac, Blue-Cream (Tortie) and Bicolour

When choosing a British Shorthair kitten, one of the most common questions is:

“What colours could this pairing produce?”

At La Bella Vita Cattery, we mainly breed:

  • Blue
  • Lilac
  • Blue-Cream (Tortie)
  • Bicolour

This article offers a straightforward explanation of coat colour genetics in British Shorthairs, helping you understand how these beautiful variations arise.

Blue British Shorthair

The Blue coat is the breed’s most iconic.

Genetically, it is dilute black.
This means the cat has a gene known as “dilution”, which turns black into an elegant, even grey.

If both parents are blue, their kittens will be blue.
If a parent carries a “hidden” gene, such as chocolate, other colours may also be possible.

Lilac British Shorthair

The Lilac coat has a pale, delicate shade with pinkish undertones.

It occurs when:

  • The base colour is chocolate
  • The cat carries the gene for dilution

For a kitten to be lilac:

  • both parents must pass on the chocolate allele
  • both must pass on the dilution allele

If both parents are lilac, their kittens will be lilac.
If one parent is blue and the other lilac, the kittens may be blue or lilac, depending on the genes carried by the blue parent.

Blue-Cream (Tortie) British Shorthair

The Blue-Cream, also known as dilute tortie, is a female cat with a coat of mingled blue and cream.

Important:
A tortie has no white.
If white is present, the colour is described as tortie bicolour, which is a different combination.

Blue-cream colouring occurs because cream (dilute red) is sex-linked.
This is why:

  • Torties are almost always females
  • Male torties are extremely rare

If the mother is blue-cream:

Males

  • Blue
  • Cream

Females

  • Blue
  • Blue-Cream

This is one of the most interesting pairings from a genetic perspective.

Bicolour British Shorthair

The Bicolour pattern is not a base colour; it reflects the presence of the white-spotting gene.

It can be:

  • Blue Bicolour
  • Lilac Bicolour
  • Blue-Cream Bicolour

White is “added” to the main coat colour.

If one parent is bicolour, some kittens may have white markings.
If both parents are bicolour, the likelihood increases.

Simple Examples of Breeding Pairs

Here are the most common pairings in our cattery:

Blue × Blue

Kittens:

  • Males → Blue
  • Females → Blue

100% Blue

Blue × Blue-Cream

Kittens:

  • Males → Blue or Cream
  • Females → Blue or Blue-Cream

Lilac × Lilac

Kittens:

  • Males → Lilac
  • Females → Lilac

100% Lilac

Blue × Lilac

Kittens:

  • Blue
  • Lilac (only if the blue parent carries chocolate)

Blue Bicolour × Lilac

Kittens:

  • Blue or Lilac
  • With or without white

Why Can’t Every Outcome Be Predicted with Certainty?

Any cat may be a carrier of genes that are not expressed in its coat.
These genes may be expressed in the kittens even when they are not visible in the parents.

That is why a responsible cattery:

  • Studies bloodlines
  • Analyses pedigrees
  • Plans pairings carefully
  • Puts health before colour

Colour Matters, but Health Comes First

Coat colour genetics in British Shorthairs is fascinating, but it is only one factor to consider.

Above all, a kitten should be:

  • Healthy
  • Well socialised
  • Even-tempered
  • True to the breed standard

If you would like to know which colours are available in our litters or learn more about genetic combinations, La Bella Vita Cattery is always happy to answer your questions openly and enthusiastically.

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