Gene W |
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WHITE Gene WGene W is responsible that all the coat is white. |
Possible gene combinations
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Non-White Gene wGene w is recessive to gene W. A cat must carry gene w twice (ww) not to have a white coat. All non-white cats - solid coloured, silver, tabbies, siamese, burmese, all bicolours - carry ww. |
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White cats are like a juke box, you can't see from outside what's in it. From heterozygous white cats you might get coloured kittens depending which cats are behind. To study the pedigree will prevent you from being surprised. | |||||||
White colours
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genetic code
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You are partly right. There is a theory that white cats might be deaf. White cats with
blue eyes are most likely to inherit deafness. Deafness will be found on that ear where
the blue eye is placed, that means also odd eyed white cats might be deaf, unilateral. The
probability is quite high with white cats with blues eyes, more than 20%.
"After all that it should be forbidden to breed with white cats !" Why ?
Breeding cats is an artificial way of reproducing cats, as it is controlled by humans and
we don't allow our cats to reproduce themselves as often as it would be possible and our
cats would like to do so.
Therefore why should we not control our breeding programs by strict selective breeding
that we don't produce deaf white cats ?
By the way the white colour is not an artificial colour, not a man-made colour, you'll
find a lot of white mammals in nature. Do we all distinguish them because they are white ?
You see, this question is not as simple to be solved as it appears to be. This question
wether to breed with white cats or not has a lot more impacts, this question is from the
same quality as one could ask
"Why is it permitted to have cars ?"
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"But they can have a catalysator." | Right, the catalysator for white cats that they don't produce deaf cats, are the Coloured cats. |
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"But traffic can be regulated by public transport systems." | Right, our regulation to filter out deaf white cats clearly are our Audiometric test programs. |
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"But accidents can be avoided by rules and strict control mechanisms of the traffic ." | Right, our control program for white cats are our Rules for breeding which guide our breeders not to produce deaf white cats. |
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"But there are electro cars or cars driven with water steam." | Right, Selective breeding programs will help breeders to keep the natural ressources of white cats intact, their possibility to hear. |
May be, You've got a small idea that apodictic rules and taboos don't bring anything
for the white cats.
"Don'ts and No's" will not stop people from breeding white cats
and, even worse will increase the amount of deaf white cats.
Information, carefully planned guidelines and selective breeding programs make it possible only to have white cats which all do hear.
If you've read the little aphorism carefully, the solution of this crucial
problem named deafness are the CARS.
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If you use coloured cats with your white cats, you've already started to reduce deafness. |
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If you test all your white cats sorrowfully with an audiometric test you're already on your way. |
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It's up to each club, federation to help their breeders with thoroughly planned breeding rules. |
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If we all only use white cats which can hear on both ears we will solve the problem together. |
You remember, in the beginning I wrote that it is one 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 - you remember, the gene for piebald spotting, called bicolour
- 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 when you think about the hungarian shepherd or the Akita inu,
which both are bicoloured.
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.
Concerning the first theory that gene W is involved in the inheritance of deafness there
are existing a lot of statistical data. But's worthwhile to start investigations on
bicoloured cats and collect statistical data, too.
As we've discussed gene W covers all colours - is called a mimic gene,
we'll make some small examples to see what we can get.
It's irrelevant if the male or the female is white. Therefore we'll assume that the female
is white.
Example 1
Our male might be blue tabby: A- B- dd ii oo ss tbtb ww
Note that I'll not write the pairs ii, oo and ss in the following table as they are not so
relevant and our combinations would get too long and difficult to read.
Our female is the white one: W-
That's all what we know about our female.
You breed this two cats and get the following litter:
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If you look to the first row of our table: All those kittens are white, homozygous or
heterozygous for gene W. Remember, that there is only one gene W necessary to get an
entire white coat. If you look to the second row of our table, there are 2 possibilities: Nr. 1: If all these kittens are white - therefore they carry Ww - your female could be homozygous for gene W or not. Nr. 2: If these kittens are coloured, then you really know for sure that your female is heterozygous for gene W. It depends now what's behind your female. You've to study her pedigree. |
Let's make the following assumption: You've got blue and red kittens out of this
mating.
Then you can make the following conclusions about your female that she must carry at least
the following gene pairs:
This example demonstrates how you can figure out the genetic background of your
breeding cats on behalf of their litters what you get from them. And so, step by step
(litter by litter) you can draw conclusions about the genetic background of your cats you
use for breeding.
This example also demonstrates the mimic character of gene W, gene W covers every colour,
turns every colour to white.
Example 2
Let's stay with the litter of Example 1. You should watch them carefully.
Mostly white kittens have a coloured patch on the top of their head which
disappears when the kittens grow up. If you are lucky to find out of which colour this
patch is you have come a step further. This coloured patch tells you something about the
genetic background of this white kitten:
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Last modified on 99-01-16