# BSH Colours - what to read?



## flosskins (Jan 27, 2010)

Hi,

I am really trying to research british shorthair colour genetics in depth, for example which colours are dominant to which, what colours can carry which and what to breed with what to produce the required colour. I have the basics, eg dilute cannot carry the base colours but I'm looking to find out things like which of black, blue and red are the most dominant, can blue carry chocolate and if so can chocolate carry blue etc. Please could people recommend good reading material to help me?

Thanks


----------



## we love bsh's (Mar 28, 2011)

this is going to be a very interesting thread.
Gskinner where are you.


----------



## messyhearts (Feb 6, 2009)

Blue & Chocolate are separate. 

Blue is a diluted form of Black.

Lilac would be a diluted form of Chocolate.

The gene you are thinking of is the diluting gene.

I believe Red is dominant but I don't know much about that. Dilute Red would be Cream.


----------



## spid (Nov 4, 2008)

Stupid me!!!! Deleted/

The Basic Self (Solid) Colours of Cats have a look on here


----------



## OrientalSlave (Jan 26, 2012)

Black is dominant over Chocolate which is dominant over Cinamon.

Red is epistatic - it covers up whatever is underneath, as does Dominant White.

So:
A black cat can carry chocolate or cinamon, or be homozygous for black.

A chocolate cat can carry cinamon or be homozygous for chocolate.

A cinamon can't carry anything.

As said above, dilute turns black into blue, chocolate into lilac and cinamon into fawn. It's recessive so a kitten has to inherit it from both parents, and two black cats can have blue kittens.

So, if you mate black carrying cinamon and dilute with chocolate carrying cinamon and dilute all six colours are possible.

Dominant white (DW) is epistatic - it covers up whatever colour the cat is underneath. Depending on what they are under the white, two white cats can produce any other colour cat unless one or both are homozygous for DW.

Red is sex-linked and on the X gene which means normal males are red or not red, females are red, tortie or not red. The dilute of red is cream. To produce a red male you need a tortie or red female, and to produce a red female the male must be red and the female tortie or red. All female kittens from a red male will be tortie or (if mother is tortie or red) red.

There is also the dilute modifier. That turns blue / lilac / fawn into caramel (different shades of caramel) and cream into apricot.

Don't ask me about silver!


----------



## spid (Nov 4, 2008)

Ah, I see - I read that bit wrong before then. 

Now silver I am better at - it acts a bit like tabby as it is dominant (only one gene needed for it to be expressed) - what gets me is the different effects the silver has - for example Bomber is a Black smoke but it heavily smoked almost shaded but not quite. How those genes get decided confuses me.


----------



## lymorelynn (Oct 4, 2008)

Oh please Oriental Slave - I want to ask you about silver  - my blue point Siamese girl has silver oriental in her pedigree (2 generations back) so can't be on the usual Siamese registers  I'd really like to know why (I know the BAC and GCCF policy) and what effect the silver has on Siamese


----------



## gskinner123 (Mar 10, 2010)

I learned, many years ago, from The Book of The Cat, published (I think) by Pan. It's an old'ish book but you can still find copies. It's not specific to colour genetics but has a dedicated section. It's the only reading material on colour genetics that I found I could follow and really absorb properly - though it took some while! I really can't recommend it highly enough.

Once you grasp the basics of colour genetics (especially with a breed like the BSH where the genetics are simple compared to many other breeds) you'll be suprised at how easily it all clicks into place in your mind. I think the worst thing anyone can do, if they want to have a better understanding of colour genetics, is to use on-line colour prediction programmes. I think it's pretty useless to know what you're going to get without knowing why or how!


----------



## becbec31 (Jun 26, 2009)

This is a helpful website. [URL="http://www.britishbluekittens.com/color.html"

Colour genetics is a real interest to me I think the internet is a brilliant tool for research.


----------



## gskinner123 (Mar 10, 2010)

lymorelynn said:


> Oh please Oriental Slave - I want to ask you about silver  - my blue point Siamese girl has silver oriental in her pedigree (2 generations back) so can't be on the usual Siamese registers  I'd really like to know why (I know the BAC and GCCF policy) and what effect the silver has on Siamese


I think some of us in the BSH section would like the answer to that question too. Without going into great and boring detail about the BSH reg policy, basically speaking cats with silver in their pedigree have their reg slip overstamped with (I've gone blank!)... I think it's just worded "silver in pedigree". And the overstamping stays on for good, however many generations you work down. Part of the reason this came about was the result of the powers that be (you know, those few people within a breed who seem to wield a disproprotionate amount of power over everyone else on BAC's and various GCCF committees) thought that some breeders were, unbeknown to them, wrongly registering (for colour) certain cats where there was silver in the pedigree... i.e. what they thought, for example, was a cream self with a bit of an unsound coat, was actually a cream smoke - in effect the silver had been carried down the generations and "missed" by some breeders when visually identifying kittens. So the overstamping is used as a supposed cautionary measure to alert breeders that silver is present, even though it cannot be carried recessively, and that they should be aware of this when identifying kittens for colour.


----------



## Soupie (Sep 2, 2008)

Silver's not hard 

Bomber is absolutely typical black smoke longhair in kitty coat - the tabby markings are ghosting which will go when her adult coat comes through. Smoke is a silver self - 1/3 silver to 2/3 colour on the shaft.

Chinchilla, Pewter,Cameo and shaded are the complicated ones as all expressions of silver and tabby genes and all possible in Selkirks but we can only register as tipped (chinchilla) or shaded ....


----------



## spid (Nov 4, 2008)

But Bombs is more than 1/3 silver 2/3 rds colour - easily 2/3 silver (if not more) 1/3 colour - so what does that make her? I'm guessing at just a light smoke


----------



## flosskins (Jan 27, 2010)

Thank you very much for all your replies so far, I think I'm getting it. I have ordered the book of the cat 

So - black is dominant to chocolate which is dominant to cinnamon
therefore blue is dominant to lilac which is dominant to fawn

Are white and red dominant over everything - eg if a red boy was put to a black girl all kittens would be red? Red seems to be the one that confuses me!

Is 'dilute' carried as a gene to work on any colour or is it carried as a specific colour, eg does a black cat from BlackBlack x LilacLilac parents carry 'dilute' to turn black to blue, chocolate to lilac etc or does it carry lilac specifically?

Can anybody explain tabby/spotted to me? is it dominant, what are the differences and how are some silver and some not?


----------



## Soupie (Sep 2, 2008)

spid said:


> But Bombs is more than 1/3 silver 2/3 rds colour - easily 2/3 silver (if not more) 1/3 colour - so what does that make her? I'm guessing at just a light smoke


Just high expression silver - wait until she gets her adult coat she may well look much darker - all the black smoke Selkirks I have known have had lighter baby coats in part due to the effect of the ghost tabbying. When their adult coats come in they look darker and lose the tabby markins 

Flosskins try THE MESSYBEAST as well


----------



## we love bsh's (Mar 28, 2011)

The book of cats whos it by?


----------



## OrientalSlave (Jan 26, 2012)

I don't know much about the genetics of silvers, something else is involved in some of the colours - the wide banding gene or similar.

However don't assume overstamping and registration policies are necessarily logical! Especially since most of them emerged before gene testing became as available and cheap as it is today. My own feelings - note feelings, not knowledge - is that quite a few of them were influenced a long while ago by prejudice, and by lack of knowledge about the genetics of coat colours. Indeed to my mind it still goes on. Offspring of Oriental bicolours without white are registered as bicolour varients and can't be shown, though they can be used in breeding. To my mind is no logical reason for this - white markings are not going to appear in their offspring as they don't have the white spotting gene.


----------



## flosskins (Jan 27, 2010)

can anyone answer my question about the dilute gene?

Is 'dilute' carried as a gene to work on any colour or is it carried as a specific colour, eg does a black cat from BlackBlack x LilacLilac parents carry 'dilute' to turn black to blue, chocolate to lilac etc or does it carry lilac specifically?


----------



## OrientalSlave (Jan 26, 2012)

flosskins said:


> can anyone answer my question about the dilute gene?
> 
> Is 'dilute' carried as a gene to work on any colour or is it carried as a specific colour, eg does a black cat from BlackBlack x LilacLilac parents carry 'dilute' to turn black to blue, chocolate to lilac etc or does it carry lilac specifically?


Dilute works on any base colour - black, chocolate, cinamon - and also on red - and turns them to blue, lilac, fawn or cream.

It's the same gene in each case and it's inherited independantly of the base colour.


----------



## Treaclesmum (Sep 26, 2011)

Silver also has the unique ability to become 'tarnished' - apparently the silver gene can break down as the cat gets older and can make the coat look brown, either in places or all over. Jumpy has gone a bit brownish in places, but he is mainly silver tabby and was more silver when he was a baby. So sometimes when you see a brownish tabby, they could be genetically silver!!! This is less common in pedigree lines I believe, if both parents are silver, but more common in moggie silvers.


----------



## flosskins (Jan 27, 2010)

OrientalSlave said:


> Dilute works on any base colour - black, chocolate, cinamon - and also on red - and turns them to blue, lilac, fawn or cream.
> 
> It's the same gene in each case and it's inherited independantly of the base colour.


Ok so a black cat carrying dilute and chocolate could produce black, blue, chocolate and lilac? Getting confused now, had it in my head that they carried a certain colour rather than the gene dilute!

Any more help with reds, torties and tabbies anybody? I dont understand how you get torties if red is dominant to everything. I guess tabby is a dominant allele as tabhy kittens have to have a tabby parent. Is spotted the same gene, and is spotted or tabby the most dominant?


----------



## flosskins (Jan 27, 2010)

If you mated a lilac with a cinnamon that didnt carry dilute would you get chocolate?


----------



## we love bsh's (Mar 28, 2011)

Im not sure about your question but i do know that 2 dilutes can only produce dilutes


----------



## OrientalSlave (Jan 26, 2012)

flosskins said:


> If you mated a lilac with a cinnamon that didnt carry dilute would you get chocolate?


Yes, unless the lilac carries cinnamon in which case you could get that as well as chocolate.


----------



## we love bsh's (Mar 28, 2011)

OrientalSlave said:


> Yes, unless the lilac carries cinnamon in which case you could get that as well as chocolate.


does this happen because the cinnamon is a base colour? so does it give the lilacs kittens born a full base colour back if you understand that.


----------



## spid (Nov 4, 2008)

re the red gene - it is a sex linked gene - so when mi=xed with other colours (ina c=girl) it can only dominante if there are two copies of the gene - in boys they only need one copy.

taken from messybeast
_The ginger colour of cats (known as "yellow", "orange" or "red" to cat breeders) is caused by the "O" gene. The O gene changes black pigment into a reddish pigment. The O gene is carried on the X chromosome. A normal male cat has XY genetic makeup; he only needs to inherit one O gene for him to be a ginger cat. A normal female is XX genetic makeup. She must inherit two O genes to be a ginger cat. If she inherits only one O gene, she will be tortoiseshell. The O gene is called a sex-linked gene because it is carried on a sex chromosome. Tortoiseshell cats are therefore heterozygous (not true-breeding) for red colour.

The formation of red and black patches in a female with only one O gene is through a process known as X-chromosome inactivation. Some cells randomly activate the O gene while others activate the gene in the equivalent place on the other X chromosome. This only shows up visibly in skin cells as these produce pigment. This occurs early on in the embryo and as skin cells multiply, they form patches. The skin is a mosaic of cells where some have the O gene active (making ginger pigment) and some do not (making black pigment). This can only happen in cats with two X chromosomes. Male cats only inherit one X chromosome so this is active in all skin cells as there is nothing equivalent on the Y chromosome which could "switch off" the O gene._


----------



## OrientalSlave (Jan 26, 2012)

flosskins said:


> Ok so a black cat carrying dilute and chocolate could produce black, blue, chocolate and lilac? Getting confused now, had it in my head that they carried a certain colour rather than the gene dilute!
> 
> Any more help with reds, torties and tabbies anybody? I dont understand how you get torties if red is dominant to everything. I guess tabby is a dominant allele as tabhy kittens have to have a tabby parent. Is spotted the same gene, and is spotted or tabby the most dominant?


The base colour is inherited completely independantly to dilution so your black cat could indeed produce all those colours, depending on what it is mated with.

Red isn't exactly dominant - the cat is still black / chocolate / cinnamon under the red and they continue to be inherited exactly as if the cat wasn't red. The red gene alters the kind of colouring produced in the hair shaft from eumelanin (black / brown / cinnamon) to Pheomelanin (red).

Tabby cats have an active Agouti gene. I write that A. Mostly I would write them A- as unless they are test mated we have no idea if they carry self (non-agouti, a) or not. A self (plain colour cat) will be aa, and a tabby carrying non-agouti Aa. So, two non-agouti carriers can produce self kittens.

There are other genes that control what the cat's tabby pattern is, all cats have these and you can often see ghost tabby markings especially on black cats that have been in the sun, or kiittens, which show this.

Red is unusual as it's sex-linked - it's on the X chromosone. It's inheritance is completely separate to the base colour, and to dilution, and to agouti. However in red cats you can always see the tabby pattern to some degree even if it's a self cat.

So, normal boys are XY so the are either red or are not red. All their daughters will be tortie (or red) but they can only pass black / chocolate / cinnamon to their sons, as the sons get the Y gene. Hence, all red male cats have a tortie or red mother and that's where their colour has come from.

Since a female is XX, that could be written as oo instead where 'o' means she doesn't have the red gene.

If she is a tortie she could be written Oo, and if she is red then OO. What happens here is that only one 'X' gene will be active in each cell in the kitten, and somewhere along the line one or the other is turned off. The colour of the fur depends which one of the two original X genes that bit of the cat has come from. What is interesting is that this happens earlier in the foetal development of tortie cats with white markings so rather than a mingled pattern they tend to have obvious patches of red, black & white. The tabby pattern will show on the red patches.

So you can write out little tables of what could be produced. Obviously a red male with a red female will only produce reds, and a non-red male with a non-red or tortie female will never produce reds.

Obviously there are several possible interesting combinations - tortie female (Oo) x non-red male (O), red female (OO) x non-red male (o), non-red female (oo) x red male (O) and tortie female (Oo) x red male (O). It would be too much to reproduce here and unfortunately I can't find any online examples.

The big point is that all of these things are inherited separately - non-agouti, base colour, dilution, red and the things not mentioned here. When you see a red cat, remember it's black / chocolate / cinnamon underneath and if the red isn't inherited by it's offspring that's how it will breed.


----------



## Soupie (Sep 2, 2008)

Cinnamon and fawn when expressed in conjunction with Chocolate/lilac will give Chocolate.

Working example:

I bred a smoke colourpoint carrying dilute and chocolate - she was mated to a cream boy who carries cinnamon.

Kitten is a lilac colourpoint - he carries cinnamon as the lilac has been made up of the chocolate and dilute genes from mum and the cinnamon and dilute genes from dad.


----------



## flosskins (Jan 27, 2010)

Thank you! I think I am getting there. 

Last questions, I promise. Is spotted dominant to tabby, and if I bred a chocolate silver spot with a lilac what would I get?


----------



## OrientalSlave (Jan 26, 2012)

Does your choc silver spotted carry dilute?

Is the lilac self or tabby?

Personally I wonder at most self x tabby matings. We all know the pattern is better on some cats than others, and for tabby I would have thought you are breeding for a nice clear pattern whereas for self for the minimum of ghost tabby, and it strikes me the two aims will be working against each other. I realise it might be a way to get a new colour or bloodline in, but I can't see it will produce a better tabby pattern or a clearer self.


----------



## Soupie (Sep 2, 2008)

Spotted is a tabby pattern .....


----------



## OrientalSlave (Jan 26, 2012)

Soupie said:


> Spotted is a tabby pattern .....


Yes, misread it and thought you meant dominant to some other tabby pattern. Do you mean to self? Tabby is dominant to self, but if the lilac is a self it will nevertheless have tabby genes, who knows for what pattern. Remember a self cat is a tabby cat with the pattern made (almost) invisible, not with the pattern genes removed.


----------



## flosskins (Jan 27, 2010)

I just wondered which pattern was dominant if you bred a spotted to a classic tabby? not planning any of these, just trying to get the differences straight in my mind!


----------



## gskinner123 (Mar 10, 2010)

Of the different tabby patterns, ticked is the most dominant, then spotted, then classic. There's always been a question over whether mackerel tabby is a distinct, separate pattern/gene in itself; the thinking seems to be that it is not and is just a polygenic (i.e. minor genes) form of the spotted pattern whereby the spots down the flanks become linked to form stripes instead of spots. Given that you see many cats that are indeterminate between mackerel/spotted, i.e. some spots, some stripes, I think that's probably the case.


----------



## Treaclesmum (Sep 26, 2011)

gskinner123 said:


> Of the different tabby patterns, ticked is the most dominant, then spotted, then classic. There's always been a question over whether mackerel tabby is a distinct, separate pattern/gene in itself; the thinking seems to be that it is not and is just a polygenic (i.e. minor genes) form of the spotted pattern whereby the spots down the flanks become linked to form stripes instead of spots. Given that you see many cats that are indeterminate between mackerel/spotted, i.e. some spots, some stripes, I think that's probably the case.


Maybe, although according to the charts I've seen, broken mackerel stripes are not round, they're more elongated, whereas spots are more round!

Yes, spotted is dominant over classic.


----------

