Gene S, s |
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PIEBALD SPOTTING gene SGene S is responsible that the coat colour gets white patches. |
Solid colour Gen sGene s is recessive to gene S. Your cat must have ss that its coat doesn't show white patches. |
Possible gene combinations
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Nr. 1 is a solid coloured cat (ss ww) and Nr. 10 is a complete white cat
(W-). Between Nr. 2 and Nr. 9 there are all ranges of piebald spotting. |
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If you want to know which Bicolours are possible, then klick here. | ||||||||
Have a look also on the Crossing table for Bicolour. |
The most popular breed known as Van is the Turkish Van, this cat has a white
body, white ears and white legs, on its head it has 2 colour patches on top of the head
near the base of the ears and the tail is fully coloured.
Exactly this pattern is called in some federations a Van-pattern (homozygous SS)
and you may find this pattern also in Persians and Exotic, in the Maine Coon and Norwegian
Forest, in British Shorthair and Europeans, in the Rex cats, etc.
A Harlequin is something inbetween a Van-pattern and a Bicolour. It has some colour
patches on its body or its legs.
To make it confusing, in some federations the Vans are called Harlequins, that means there
are only two patterns recognized the Harlequin and the Bicolour, while in other
federations there are 3 patterns recognized, the Van, Harlequin and Bicolour.
A Bicolour has mostly the back fully covered and may show 1 white patch on the
back, while the chest and stomach is white, which might go up to the flancs. The head
including the ears shows colour and white, ideally the face should show a white flame.
Legs and tail can be coloured with white patches.
In some federations tortie cats with white patches are called Tricolour - f.e.
black tortie with white or bluecream with white, in other federations these cats are
called Calicos.
In some federations cats are called Parti-Colour which are either tortie or tortie
with white.
When you read already about gene W for entirely white cat you read about that theory that
gene W together with blue eyes is the source for inheritance of deafness. That's one
theory. Another one is that gene S, the gene for piebald spotting, together with blue eyes
is the source for inheritance of deafness. According to this theory a lot more cats would
be involved with the problem of deafness.
If you think about the dogs where more than 40 breeds are likely to inherit deafness, this
theory gains plausibility.
If you're interested in that theory visit Orca Starbuck's article
about genetic.
You may also find another interesting article dealing with this subject at Lorraine Shelton's page.
Example 1
You mate the female with a Bicolour male.
Your female is black and doesn't carry chocolate or cinnamon: BB D- oo ss. The male is
blue and white and also doesn't carry chocolate and cinnamon: BB dd oo Ss.
Note, if the male doesn't show a real Van pattern, we must assume that it is heterozygous
for Piebald Spotting (Ss).
Do you think we will get Calicos ? Let's look.
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You see, you don't get a Calico. Why ? Remember, to get torties at least one of the parents must have red or cream. |
Example 2
As we have seen in example 1 we must use a male which has red or cream. So we try it again
with our female and mate her with a cream and white bicoloured male: BB dd Oy Ss.
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Remember that Red
is sex linked (male: OY, female: OO) and therefore the male can only pass once orange
to his offsprings. You see, now you got Calicos. |
Example 3: Which male can we use that all kittens are Bicolours ?
We will use a blue and white Van male to see, if all kittens will be bicoloured: BB dd oo
SS.
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If one of the parents is homozygous for Piebald Spotting (SS) all kittens will be
bicoloured. That means Vans are good for breeding bicolours. |
Example 4: How can we get Vans (homozygous SS) ?
As you have seen in the examples before, if one parent is solid (without white) we only
can get Bicolours (heterozygous Ss). Therefore we will use a black and white bicoloured
female with a blue and white bicoloured male, to see if we can get Van kittens.
Our male brings us the following genetic background: BB dd oo Ss. Our female brings: BB D-
oo Ss.
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If both parents are at least Bicolours (heterozygous for Piebald Spotting: Ss) we can get Van offsprings. |
If you want to know which Bicolours are possible, then klick here.
� European Cat Fancy 1997-1999. Please respect the Copyright. Please contact us at [email protected].
Last modified on 99-01-16