Genetic terms in cats

Genetic terms in cats
Genome of the cat
Dominance of genes
Cat Breeding techniques
Crossing Table 1
Crossing Table 2
Crossing Table 3
Gene A: Agouti
Gene B: Black
Gene C: Full colour
Gene D: Diluted
Gene Dm: Dilute modifier
Gene Fd: Folded ears
Gene I: Inhibitor
Gene L: Shorthair
Gene Mc: Mackerel
Gene O: Orange
Gene S: Piebald spotting
Gene W: White
Gene XY: Sex
Quality Points for Cats


Terms used in genetics of cats

Don't worry, you will not be overwhelmed with high sophisticated genetics. The lessons are kept as simple as necessary. You will get many examples from the breeding practice, because all science is as good as we can use it.
At least you should become familiar with some few basic terms which will be used in the following lessons.


Genes have their special loci on the chromosomes and are the basic elements on which heriditation is based upon.
There are genes responsible for each feature of your cat to be inherited, for eye colour, bone structure, coat texture, coat colour, temperament, etc.
Genes are always present in pairs.



Alleles are different mutants of the same gene.
For example:
The gene responsible for the coat colour "Black" has 2 mutants, one for chocolate and one for cinnamon.


Your cat is said to be homozygous for one feature when it carries in its responsible gene pair the same gene twice, that means both genes of the gene pair are equal.


Your cat is said to be heterozygous for one feature when the genes of the responsible gene pair are unequal.


How your cat looks like is called phenotype, it is the summary of all the features you can see on the outside of your cat.


How your cat looks like inside, which features it can possibly inherit - you can't see those - is called the genotype, it is the summary of all genetic information which your cat carries and can inherit to its litter.


A gene is said to be dominant when its effect can be seen in the phenotype of your cat.
Only one dominant gene in the gene pair must be present to be seen in the phenotype of your cat.

For easy reading dominant genes are written in capital letters.
F.e. the gene B (for Black coat colour) is dominant over the gene b (for chocolate coat colour).


A gene is called recessive when its effect can not be seen in the phenotyp of your cat, when only one gene is present.
The same gene must be present twice in the gene pair that you can see its expression in the phenotype of your cat.

For easy reading recessive genes are written in small letters. In our example: the gene b must be present twice (bb) that the coat colour becomes chocolate.

That's all what you need to know first.

[A] [B] [C] [cb & cs] [D] [Dm] [Fd] [I] [L] [Mc] [O] [S] [W] [XY]

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