Crash Course in Genetics
Within each one of your cells' nuclei, are chromatin. Whenever cells multiply, these spools of loose DNA are wound up and packed into chromosomes. Humans have twenty-three pairs of chromosomes, but some organisms have more or less. Cats have nineteen pairs of chromosomes, eighteen for genetic information, and one for sex determination.
Alleles are places on chromosomes that can have variation. They make humans, and cats, unique. Alleles can be dominant, recessive, codominant, or incomplete dominant. Dominant alleles will always show in an organism's physical form (phenotype) and are represented with a capital letter. Recessive genes are the opposite; they only show up when two copies of the same allele are passed on to the child by the parents (homozygous alleles). Codominance is a mix of the two: when one copy of one allele is different from the other (heterozygous), but they both get expressed, like tortoiseshell cats. Finally, incomplete dominance is just like codominance, except the two phenotypes blend. Your fingerprints are an example of incomplete dominance in action (look for loops!). 4DC requires all cats submitted to have a genotype, or a record of its genetic code. Why? It helps ensure realism and makes making kits much easier.
Writing down a genotype for 4DC is simple: you use this (simple) or this (complex) website, and plug in what your cat looks like. I explain each of the alleles in more depth below.
If the genes you know your cat has do not appear in this list, contact staff. We'd be happy to help you out!
Alleles are places on chromosomes that can have variation. They make humans, and cats, unique. Alleles can be dominant, recessive, codominant, or incomplete dominant. Dominant alleles will always show in an organism's physical form (phenotype) and are represented with a capital letter. Recessive genes are the opposite; they only show up when two copies of the same allele are passed on to the child by the parents (homozygous alleles). Codominance is a mix of the two: when one copy of one allele is different from the other (heterozygous), but they both get expressed, like tortoiseshell cats. Finally, incomplete dominance is just like codominance, except the two phenotypes blend. Your fingerprints are an example of incomplete dominance in action (look for loops!). 4DC requires all cats submitted to have a genotype, or a record of its genetic code. Why? It helps ensure realism and makes making kits much easier.
Writing down a genotype for 4DC is simple: you use this (simple) or this (complex) website, and plug in what your cat looks like. I explain each of the alleles in more depth below.
If the genes you know your cat has do not appear in this list, contact staff. We'd be happy to help you out!
Fur
The most simplistic of the alleles to explain, fur length is a simple dominant/recessive. Short fur (L) is dominant over long fur (l).
Black, Brown, Cinnamon
Black is the main coat colour of all cats. Every cat has black alleles, even if they don't show it. Black (B) is dominant over chocolate (b), which is dominant over cinnamon (bl). Brown cats that aren't tabby are quite rare!
Dilution
Dilution lightens the coat colour. Black cats become blue/grey, orange cats become yellow, brown cats become lilac, and cinnamon cats become fawn. Dilution is recessive (d).
Orange
Orange, also known as red, is a completely separate allele from black, and is sex-linked. Toms can only have one copy of the gene, while female cats have two. This is why only tortoiseshell cats are female, unless the male has an extra X. Orange (O) is dominant over a lack of orange (o). An Oo genotype on a female cat makes a tortoiseshell.
White-Spotting
White-spotting, also called piebald, is the presence of white fur on a cat. It is dominant (Ws) over lack of white-spotting (w). Dominant white (Wd) is, of course, dominant over both, and causes the entire cat to be white.
Tabby Stripes
Every cat is a tabby, but some don't show it! Every cat has the genes for tabby patterns, but another gene controls whether they show up. Tabbyness is controlled by the agouti gene, which is dominant (A). In order, the tabby patterns possible are mackerel (Mc) and classic (mc). Ticked tabbies, which you would think would be on the same location, is not. Ticked tabbies are dominant (Ta), and masks all other tabby stripes. Spotted tabbies are described below.
All orange cats are tabbies. Some may be fainter than others, but ever single one displays tabby stripes.
All orange cats are tabbies. Some may be fainter than others, but ever single one displays tabby stripes.
Spotting
Spotting oversees the connectedness of tabby stripes. If a cat has homozygous spotting genes, they will be a broken spotted tabby. If they are homozygous dominant, they will be a spotted tabby. Spotting is dominant. (Sp).
Melanin Inhibitor and Wide Bands
The melanin inhibitor gene shows up on all cats, but is most visible on cats with agouti. On tabbies, the stripe colour is left the same, but the main body color becomes silver, making a silver tabby. On solid cats, it turns the base of the hair silver, making them silver smoke. Silver tabbies can have many phenotypes, from only the tip being silver (chinchilla) to the base of the hair being silver (silver shaded). Melanin inhibitor is a dominant gene (I).
Furthermore, the presence of the wide band gene without melanin inhibition but with agouti makes a golden tabby. Wide band has no effect on silver cats, from what I can tell. Wide bandedness is dominant (Wb).
Furthermore, the presence of the wide band gene without melanin inhibition but with agouti makes a golden tabby. Wide band has no effect on silver cats, from what I can tell. Wide bandedness is dominant (Wb).
Colourpointing and Albinism
Colorpoints are a type of albinism. Warmer areas of the cat stay white, while cooler areas fade into their other colours. Albinism is also located on the same place. No colourpointing (C) is dominant over all, and colourpointing (cs) is dominant over albinism (c).