# Question about British Shorthair Colour genetics - colourpoint and Lilac



## jenny wong (Mar 8, 2017)

Im currently learning about the color genetics of BSH, the only colour that I still don't quite understand is colourpoint. I hope someone can help me out with this example.
a female BRI n 33 - Sir BRI C lilac (carriers cinnamon) and Dam BRI n black (carries cinnamon) 
a male BRI C lilac - Sir BRI A blue and Dam BRI j lilac tortie
so what color could their offsprings be?


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## OrientalSlave (Jan 26, 2012)

You have so much going on there it's hard to say.
However:
The girl is seal, carries dilute and either chocolate or cinnamon
The boy is lilac, you don't give any information about if he might carry colourpoint or cinnamon. Assuming he doesn't carry either:

You won't get any colourpoint kittens, or any cinnamon or fawn.
The girl carries dilute and chocolate, the boy is lilac, so on average (and you could get all black kits!):
25% black
25% blue
25% chocolate
25% lilac

On average 50% will be boys & 50% girls, my first litter was 5 boys & 1 girl. The averages are over many litters, not just one, but they help.

You could DNA test them - the girl to see if she carries chocolate or cinnamon, and the boy to see if he carries colourpoint or cinnamon.

BTW it's Sire not Sir!


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## OrientalSlave (Jan 26, 2012)

PS colourpoint works just like dilute - a cat has to inherit it from both parents to be pointed, so parents have to be pointed or carriers, plus two pointed cats will only every have pointed kittens.


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## QOTN (Jan 3, 2014)

jenny wong said:


> Im currently learning about the color genetics of BSH, the only colour that I still don't quite understand is colourpoint. I hope someone can help me out with this example.
> a female BRI n 33 - Sir BRI C lilac (carriers cinnamon) and Dam BRI n black (carries cinnamon)
> a male BRI C lilac - Sir BRI A blue and Dam BRI j lilac tortie
> so what color could their offsprings be?


The GCCF British registration policy has quite strict rules concerning colourpoint carriers so you may be able to tell from the lilac boy's registration certificate that there is a chance he carries colourpoint, in which case some of the kittens may be colourpoint but, as Oriental Slave has already said, just because a recessive pattern like colourpoint is possible, it does not mean you will automatically get colourpoint kittens. However all the offspring will carry colourpoint.


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## jenny wong (Mar 8, 2017)

Thanks so much for replying! there's still so much I have to learn! I'm reading about the GCCF British Registration policy too, which makes me a bit concern about the colourpoint. I'll try to find out more details of the lilac boy.


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## OrientalSlave (Jan 26, 2012)

Are you wanting to breed colourpoint or avoid breeding them? That's what determines what is acceptable and what register it goes on. This is where you need a mentor who knows the breed, and usually would be the person your girl came from. But always double-check for yourself - registration policies change, mentors have been known to slip up!

http://www.gccfcats.org/Portals/0/BritishSH.RegPol.pdf


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## QOTN (Jan 3, 2014)

If you don't want to breed colourpoint, a colourpoint girl is not really a sensible option in GCCF since the registration will be a bit o/f a problem for more than one generation.


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## jenny wong (Mar 8, 2017)

the boy doesn't carry colourpoint or cinnamon, so there will be 25% chance of getting black, blue, lilac and chocolate each. I think I may avoid the colourpoint girl, even though she's absolutely gorgeous! lol Thanks OrientalSlave and QOTN!


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## Lula10101 (Aug 11, 2017)

Hello, I have a question about BSH colour genetics and this seemed like the best place to put it, but I'm new on here so apologies in advance if its not!

I am trying to understand the colour gentics of the cream/torties....I've got my head around pretty much everything else, apart from that. What I am wondering is, if a blue carrying cinnamon dam is put to a cream (not carrying any chocoloate or cinnamon) sire, what colour might the kittens be? Would they be all blue tortie girls, and all blue boys, or would the cinnamon gene from the dam come into play at all? I know cinnamon is recessive and needs 2 alleles to manifest, but I'm just curious how it works with torties, since from what I have read, they have a special gene that means that both colours manifest (i.e. the cream and the blue, in the case of a blue tortie)

If anyone can shed any light on it, that would be appreciated! 

Thank you,


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## QOTN (Jan 3, 2014)

I think the question you are asking is not specifically to do with cinnamon.

A few details about the 'special' red/orange gene should provide the explanation. The red gene is located on the female chromosome. A female has two female chromosomes. Torties have a red gene on only one of those chromosomes and the basic colour is expressed when the chromosome without the red gene is inherited. Red girls have two red genes, one from each parent. A male has only one female chromosome so needs only one red gene to be a red cat. 

A red or cream sire will always pass on his red gene to his daughters but not to his sons who get their female chromosome from their dam. This means every girl will be a tortie from the mating you cite and you are correct that they will all be blue. You are also correct that cinnamon is recessive so cannot be expressed unless the gene is inherited from both parents. The basic colour genes, black chocolate and cinnamon are autosomal (located on 'normal' genes so nothing to do with the red gene.)


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## Lula10101 (Aug 11, 2017)

Thank you so much, that is really helpful. So to get a cinnamon or fawn tortie you would need a cinnamon or fawn mother, or both parents to carry that colour? 

I knew that cinnamon was recessive but got a little confused about the expression of 2 colours in torties, but it makes sense now - the kittens would be the dominant colour (or possibly cinnamon/fawn/chocolate etc if both parents are carriers?), but with the expression of cream or red if they are torties. 

Thanks again QOTN, I really appreciate you taking the time to help!


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## QOTN (Jan 3, 2014)

Lula10101 said:


> Thank you so much, that is really helpful. So to get a cinnamon or fawn tortie you would need a cinnamon or fawn mother, or both *parents to carry that colour? *
> 
> I knew that cinnamon was recessive but got a little confused about the expression of 2 colours in torties, but it makes sense now - the kittens would be the dominant colour (or possibly cinnamon/fawn/chocolate etc if both parents are carriers?), but with the expression of cream or red if they are torties.
> 
> Thanks again QOTN, I really appreciate you taking the time to help!


Just to emphasise the point about all recessives. They must be inherited from *both *parents. You cannot have cinnamon unless both parents pass it to their kittens, in the same way as you cannot have dilute unless both parents pass it on. (The only slightly confusing aspect of this rule applies to chocolate, which is recessive to black but dominant to cinnamon. To get a chocolate the offspring must have chocolate from both parents or chocolate from one and cinnamon from the other.)


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## OrientalSlave (Jan 26, 2012)

With a tortie you can see what colour she is, with a red or cream (male or female) you don't. You also don't know if they carry chocolate and/or cinnamon without DNA testing. They all have two genes for black/chocolate/cinnamon as those are not sex-linked genes so inheritance of these works the same way as with any other cat, except in the case of a red or cream it's totally masked.

Since the cream boy doesn't carry chocolate or cinnamon, all girls from the blue girl will be blue-cream and all boys will be cream. However half of them will carry cinnamon (the other half won't carry chocolate or cinnamon) and you will have to DNA test to find out which ones.

Are these BSH? If they are I prefer fawn, as to me a good orange eye colour fades into the coat in a cinnamon / cinnamon tortie. However in a fawn / fawn tortie it stands out nicely as it does in a cream.


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## QOTN (Jan 3, 2014)

OrientalSlave said:


> With a tortie you can see what colour she is, with a red or cream (male or female) you don't. You also don't know if they carry chocolate and/or cinnamon without DNA testing. They all have two genes for black/chocolate/cinnamon as those are not sex-linked genes so inheritance of these works the same way as with any other cat, except in the case of a red or cream it's totally masked.
> 
> Since the cream boy doesn't carry chocolate or cinnamon, all girls from the blue girl will be blue-cream and *all boys will be cream*. However half of them will carry cinnamon (the other half won't carry chocolate or cinnamon) and you will have to DNA test to find out which ones.
> 
> Are these BSH? If they are I prefer fawn, as to me a good orange eye colour fades into the coat in a cinnamon / cinnamon tortie. However in a fawn / fawn tortie it stands out nicely as it does in a cream.


I think you have a typo, @OrientalSlave All boys will be blue! Also some or all may carry cinnamon but they may not.. The 50% chance of inheriting it is at the point the gene is passed on and that is random.


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## OrientalSlave (Jan 26, 2012)

QOTN said:


> I think you have a typo, @OrientalSlave All boys will be blue! Also some or all may carry cinnamon but they may not.. The 50% chance of inheriting it is at the point the gene is passed on and that is random.


You are right, I do.


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## Lula10101 (Aug 11, 2017)

Thank you for helping me get my head around it all! And yes, they are British Shorthairs and I agree with you - the eye colour does stand out much more on a fawn - it is such a beautiful colour. Thanks again to everyone


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## Lisa Wright (12 mo ago)

I cant seem find where make new post but my question similar to this post if had both blue british shorthair but 1 carried the lilac Jean of there mum what colour would my kittens be


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## QOTN (Jan 3, 2014)

Two blues with only one lilac gene between them will produce all blues. Some may carry lilac but would need a DNA test to prove which they were.


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