Every cat in Catmaster carries a full genotype: pairs of alleles at real loci, with dominant and recessive genes. Kittens inherit one allele from each parent – so coat colors, patterns and hidden traits follow the same rules as in real cat breeding.
Each cat has gene pairs at loci like brown, dilution, agouti, tabby or colorpoint. A capital letter means a dominant allele, lowercase a recessive one – exactly like in genetics textbooks.
A kitten receives one allele of every gene from its mother and one from its father. Recessive traits can hide for generations behind a dominant allele – and suddenly reappear in a litter.
Before you pair two cats, the game simulates thousands of possible litters with the real birth engine and shows you the probability of each color and pattern.
Ragdoll colors are computed from the genotype, not picked from a list. A few examples of how genes combine:
| Color | Genotype behind it |
|---|---|
| seal | dominant BROWN allele, no dilution |
| blue | seal + two copies of the dilution gene |
| chocolate | two recessive brown alleles |
| lilac | chocolate + dilution |
| cinnamon | two copies of the rare brown1 allele (5% frequency) |
| fawn | cinnamon + dilution |
| orange / cream | X-linked orange gene (cream = diluted orange) |
| tortie („spots") | female carrying one ORANGE and one orange allele |
Point intensity matters too: a cat with two siamese alleles shows stronger points than a heterozygous one.
Body patterns: bicolour, highmitted, mitted and van, plus face and leg markings. Tabby stripes only show with at least one dominant AGOUTI allele.
Four tabby patterns – classic, mackerel, spotted and ticked – plus silver and cameo shaded coats driven by the inhibitor gene, and 22 eye color variants.
True to the breed standard: only blue, from light ash to dark slate, controlled by a dedicated intensity gene.
Not everything is visible on the coat. Some traits stay hidden until you investigate them.
From infertile (5% of cats) through low and average to good and high. Fertility decides the chance of successful conception – from 40% up to 95%.
A separate hidden trait decides how many kittens a queen can have: from 1–2 up to 3–5 per litter.
A fertility test at the vet (150 Cat Coins, 7-day cooldown) reveals both hidden traits at once. Without it, a tomcat cannot be offered for stud.
Cats can silently carry chocolate, cinnamon or dilution. Rare spontaneous genes exist too: vitiligo (0.5%), heterochromia (0.1%), blindness and albinism (0.01% each).
Every cat has a family tree of up to 5 generations. In the Breeder Academy you can certify a full 3-generation pedigree (500 CC) or a 4-generation one (1500 CC). Show wins earn champion points: 10 points make a Champion, and 30 points plus a 4-generation certificate make a Grand Champion.
Yes. The game models real loci with dominant and recessive alleles, X-linked orange, dilution and pattern genes. Kittens inherit one allele of each gene from each parent, so breeding outcomes follow real probability.
Yes. Before breeding, the game runs thousands of simulated litters with the same engine that generates real kittens and shows the probability of each color and pattern.
Take the cat to the vet for a fertility test. It reveals both fertility and litter size. Revealed genes are shown on the cat’s card and can be filtered on the market.
Pair your first cats and watch the genes do their work. Free, in your browser.
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