The Silver trait is a dominant trait. With dominant means that the cat only needs to have ONE copy of the gene for it to appear. So you if you see it, it’s there, if you do not see it, there is also nothing to inherit.


But most rules got exceptions,  I just want to mention it very briefly and it’s not something we should go deeper into, but it has been proven over the years that the silver sometimes hides, especially on blue cats. The cat appears to be non-silver, but it got the silver gene and inherits it to its offspring.  So there are cats with "invisible" silver, although this is relatively uncommon.

Then we have the purely linguistic that can make it hard for new, a cat with this gene is called different depending on whether it is agouti or non-agouti.

 

Agouti = Black silver tabby, red silver mackerel tabby , blue silver ticked tabby etc….

Non-Agouti = Blacksmoke, Redsmoke, Bluesmoke etc ...

In this article, I will talk about the trait itself and will just call it silver.

 

The silver trait is designated I (for the inhibitor gene).

 

 ii

Non-silver

The cat has no silver gene and will not show silver nor inherit any silver.

 Ii 

Heterozygous silver

The cat has one copy of the gene and will be able to give either silver or non-silver to its offspring.

 II

Homozygous silver

No matter what the cat is mated with, all offsprings will be silver if the parent is homozygous since it will always inherit one copy of the gene (I).

 

If we do a test mating, one can easily see that two non-silver will never ever be able to get any kittens that are silver, however, two heterozygous silver will be able to get kittens that are non-silver.

 

As can be seen in the table below, where both mom and dad are non-silver, the kids will also be non-silver. Thus, as seen here, there is no I, only i.

Male

i

Male

i

Female

i

ii

ii

Female

i

ii

ii

 

Om vi då tar ett annat exempel så kommer vi här att se ett annat scenario, både mamma och pappa är här Silver men båda är heterozygota och har alltså endast 1 uppsättning av silver-anlaget.
I detta exemplet kommer 50% att bli silver men “bärare” av icke-silver. 25% kommer att bli homozygota silver och 25% kommer att bli icke-silver.

 

If we take another example then we will see another scenario here, both mother and father are here Silver but both are heterozygous and got 1 set of the silver-trait.

In this example, 50% will be silver but carriers of non-silver. 25% will be homozygous silver and 25% will be non-silver.

Male

I

Male

i

Female

I

II

Ii

Female

i

Ii

ii

 

Om vi tar ytterligare ett sista exempel där vi gör mamma till homozygot silver, så ser vi här nedan att samtliga avkommor blir silver. 50% kommer att vara heterozygota och 50% homozygota.

 

If we take another last example were let the female be homozygous silver, and then we will see below that all offspring become silver. 50% will be heterozygous and 50% homozygous.

Male

I

Male

i

Female

I

II

Ii

Female

I

II

Ii

 

There is not much more to say about silver genetics when it comes to silver itself. However, silver can be tricky and can have a wide range of expressions, everything from very vague silver to cats with razor-sharp contrasts.

 

Now I will get into a very exciting part but also a very tricky one, and remember that here we are no longer talking about certain facts but only about theories of which there are a lot.

I am talking about the patterns Shaded/Shell, (I will not deal with golden in this section other than very very brief, this will be complicated enough anyway).

 

For many, many years, a theory of an incompletely dominant wideband-gene has been put forward, at least in our neighborhoods, as the cause of these colors.

Chinchilla (old designation it’s now called shell for all colors)/Shell = WbWb (ems code: 12)

Shaded = Wbwb (ems code: 11)


However, this theory has begun to be questioned by both researchers and breeders.

 

One of our most persistent researchers, regarding the color-genetics on cats, Leslie Lyons, says that today the wideband-gene is suspected to be recessive, so two copies of it are required for the trait to appear. But then we get to the question, IF now the wideband-gene is recessive, then what makes chinchilla/shell? The theories are that we are talking here about polygenes and selective breeding of the brightest cats.

 

Until we have a genetic explanation, we have to settle with the fact that this is something we are only able to have theories about. We simply don't know anything for sure. Or, well, we have succeeded in finding out by studying pedigrees and cats that we are most likely dealing with a recessive wideband-gene.

 

One could say that the wideband-gene turns on or off the trait itself, then polygenes play a part in how light the cat gets, whether it falls on the border of normal silver or on the border with Shell or even becomes Shell, it is probably the closest we come to the truth today, without knowing anything for sure.

I have studied these colors a lot lately and I have come to the conclusion that we have many more "shaded" than we think, however, we are most likely to have a lot of "bad" shaded just as we can have bad tabby, spigrés (Swedish nickname for a combination between mackerel tabby and spotted, generally bad pattern with other words) in English it would probably be called Spackerel or something.

 

Many who breed shaded today got, seen with "my" eyes, in fact, cats that are shell, I have been active on many different forums where these colors are discussed and I hear over and over and over the repetition of the words "in my opinion" pronounced. Personally, I prefer standards and some written guidelines, based on previously set rules and if we take a look at these, none of them comment on how light or dark a cat may be to be considered shaded or shell, other than that a Shell should be perceived as much lighter than a Shaded.


The gene code for Shaded/Shell according to the above theory, with recessive wideband-gene is.
A- I- wbwb  (The cat must be agouti, silver and have to copies of the wideband-gene).

 

Then how do I know if I have a shaded? What shall I to look for? Some standards are more distinct then others, in the descriptions and express themselves slightly different but you can use below as a first step.


Shaded shall have  ⅓ tipping (color) and the rest of the hair shall be white.
Shell Shall have ⅛ tipping (color) and the rest of the hair shall be white.

If you look at the standard when it comes to Shaded, then it is much more to it.
The cat should not have any visible pattern even if it is agouti, it should be brighter on the legs and sides, nor should it have any unbroken rings on the legs. Broken rings are allowed and it shall be perceived as much darker than a Shell.

The coat on the underside of the feet is colored and on the hindfeet the color may extend all the way to the joint.

 

When it comes to the Shell it is stricter, no visible pattern allowed, face and legs may be slightly tipped with very light color. They should be much lighter than a Shaded and the color of the hindlegs may not extend all the way up to the joint of the hindlegs instead they shall be without any tipping there.

Just to very briefly mention golden, the theory is that a goldenshaded is a shaded cat but without silver.

Hence the gene designation is: A- ii wbwb, if you follow the above theory. These should basically look like a shaded but the bottom shall be apricot instead of white.


Above is a good guideline to follow.  If you like to read the standard it is a good idea to read through all the standards of the different federations to get a clearer picture of what they say.

 

YankeeCatsAngelOfJoy

Yankeecats Angel of Joy
Blacksilvertortie Shaded (fs 11)
Photo: Britta Singethan

20191223 Horagalles 05 Copy

Dagdrivarn Horagalles
Red Shell

Photo: Ylva Bengtsson



By: Malin Sundqvist

Dagdrivarn (www.dagdrivarn.se)

We have long believed that white, also known as dominant white, and white spot have been two completely separate traits, but they are in fact both variants of the KIT gene. White spots can look in a variety of ways, from a small medallion here or there on the body up to an almost entirely white cat, like a harlequin or van.

 

W - trait for all white, dominant trait

Ws - white spot

w - not white spot

wg -  trait for Birman-socks type of white spot, recessive trait

 

Combined, you get:

WW or WWs or Ww or wwg = White cat

WSWS = White spot (bicolor, harlequin and van)

Wsw or Wswg = White spot (everything from medallion to bicolor)

ww or wwg = non white

wgwg = white spot of the type that gives Birman socks

 

The boundary between homozygous and heterozygous Ws white spots is not always clearly visible, which means that both heterozygous and homozygous can be bicolor.

 

Since white (W) is a dominant trait, this requires one of the parents to be white. This trait acts as a mask on top of the cat's other color. That means you can have a black silver tortie spotted or a black or a black torbie or maybe a red classic tabby under this white scrub. The cat thus bears a trait for a different color, but everything that these genes would have expressed is hidden behind the white. This is in contrast to the other two white-spot plants, which then do not mask the cat's color, instead, it pushes it aside. So it does not hide any color like the trait on the white cats does.

 

It is not uncommon for white cats to become deaf. Studies indicate that WW presents a higher risk of deafness than Ww. If the cat is WW it is basically always blue-eyed and deaf or has a hearing impairment.

There is a study suggesting that a white cat carrying the white spot trait Ws (cat genotype = WWs) has a higher risk of deafness than a white cat carrying the trait for W, without white, (genotype = Ww). Therefore, it is not advisable to mate white,  with another white or white with a white spot. If you want white cats you should strive to mate a white cat with a cat that is complete without white.

 

The W-trait and the Ws-trait may also alter the eye color of the cats. For example, both white and white spot cats with a slightly larger amount of white may catch blue eyes. As mentioned above, it is more common in homozygous all-white cats, but you can also get it on heterozygotes. These white or white-spotted cats can also sometimes be “odd-eyed”, which means that one eye is blue while the other has a normal yellow or green color. Blue-eyedness seems to be linked to a higher risk of deafness in white cats. The recessive white spot, wg, is not linked to either deafness or blue-eyedness.



MellyMooMoMoOfIvysChildren12v
MellyMoo MoMo Of-Ivys-Children
Blacksilver Mackerel Tabby-Van (WsWs)

MellyMooMoMoOfIvysChildrenAlmostNewborn

Almost newborn

DagdrivarnExtraEvaliaAdult

Dagdrivarn Extra Evalia
Blacksilver Classic Tabby-Harlekin (WsWs)

DagdrivarnExtraEvaliaNewBorn

Newborn

DagdrivarnHotNSweetAdult

Dagdrivarn Hot’n Sweet
Blacksilver Ticked Tabby-Bicolor (Wsw)

DagdrivarnHotNSweetNewBorn

Newborn

DagdrivarnMadameLaikaMelangeAdult

Dagdrivarn Madame Laïka Melangé
Blacktortiesmoke-white (Wsw)

DagdrivarnMadameLaikaMelangeNewBorn

Newborn



By: 

Malin Sundqvist (www.dagdrivarn.se)

and 

Ulrika Olsson (www.ylletrollets.se, www.pawpeds.com)

If you would describe it simply, there are two traits a cat always, always have and it is:

  • Basic color

  • A Pattern, tabby, mackerel, spotted or ticked, (it can actually be two but this will be brought up later).

Then we have a lot of different traits that will affect how the cat will look like in the end. But in this section we will only talk about the basic colors and agouti which determines whether the cat's patterns should be displayed or hidden.

By starting from scratch and forgetting all other traits that will change the color of the cat, it is easier to learn all different colors, learning the inheritance from scratch and then building it up piece by piece.

Basic Color

The basic color of a cat is always black or red, so a cat always has the trait black, red or both in a tortie.

The genetic denominations are:

Black = o

Red = O

Blacktortie = Oo

The basic color are sex-linked, which means that it is inherited on the X chromosome. As we know (if we did not sleep in school), the eggs are always X and the sperm determines the sex by being X or Y.

XX - female

XY - male

As you can see above, the males always get their color from the mother (they only have one X).

The females, on the other hand, get the color from both their mother and their father, this is why a female can become a tortie, both red and black.

Note that we now ONLY talk about the basic colors, ie red and black. So if we take the example above with Black and Red, we can see the genetic differences between males and females.

 

The genetic denominations are:

For a female:

Black = oo

Red = OO

Blacktortie = Oo

For a male:

Black = oy (y since the male has XY and therefor no color on Y)

Red = Oy

This applies to all cats, whether they are blue, cream, red, black, different types of torties, with or without silver, with or without white, with or without patterns. These two basic colors are always one of the traits in your cat, one of them or maybe both if you have a female.

 

Agouti

Now, lets move on to the next part, as I wrote at the top, all cats have a pattern (sometimes two), but we will not discuss these in this part, I will describe different patterns in the future. In this part we will only talk about the Agouti gene, it is the trait which controls whether the pattern that the cat is wearing should be displayed or hidden. But before we begin with this, I think it's good with a quick very brief basic review of dominant and recessive traits.


Dominant or Recessive

Traits is inherited in genepairs and kittens will then inherit one gene of these trait from their mother and one gene of the trait from it’s dad. Keep this in mind, go back here if it gets messy. I will trait by trait visually paint up the inheritance so it will be easier to see it in front of you in all the articles and for all traits. I will also initially state whether it is a dominant or recessive trait.

Dominant traits:
Must be seen in one of the parents to be carried on and can not be worn hidden.

For the dominant traits, this means that there is enough with ONE set of trait, for it to be seen.

Recessive traits:

Can be worn hidden, for a recessive gene to be seen, it is necessary that the cat has the trait twice. So if the cat only have one set of the trait, it is not enough for you to see be able to see it. A recessive trait can be worn hidden forever and ever before it suddenly reappears.

Nå så ska vi då efter ett sidospår för att reda ut lite grunder gå in på Agouti, detta är det anlag som bestämmer huruvida det mönster katten bär skall visas eller om mönstret skall döljas.
Agouti/Non-agouti i vardagligt tal mönstrad/omönstrad eller mönstrad/solid.

Well then, after a sidetrack, to find out some basics, lets continue with the Agouti trait, this is the trait that determines whether the pattern the cat is wearing should be displayed or if the pattern is to be hidden.

Agouti / Non-agouti in everyday speech patterned / nonpatterned or patterned / solid.
Agouti is a dominant trait.

Agouti = A

Non-agouti = a

A/A Homozygot agouti

All offspring will be patterned (agouti)

A/a Heterozygot agouti

Offspring may become agouti or non-agouti. Depending on whether the other party is A/A or A/a

a/a Homozygot for non-agouti

If this cat is mated with a non-agouti, all offspring will also become non-agouti.

Here you must keep in mind that in some colors this trait is more or less transparent, especially in red or cream. Silver and blue can also have some transparency especially at certain ages.

This allows you to see the pattern on the cat even if it is non-agouti, thus not patterned.

I usually compare red with a glaze and black with a regular paint. If you paint a board with a glaze, you will always see the underlying pattern, but if you paint a board with paint, you will not see the board's patterns through the color. Similarly, red act like a glaze and black act like a paint.

 

Here is a good example of a solid red cat (solid red) with a very clear pattern.
Dagdrivarn Prince Mozez who is aa (non-agouti).

2007 06 01 56

Here you might ask yourself how do i then see if a cat is patterned or not on a red or a cream? There are ways to see this, if we only have red and cream, it's easier, if you mix in for example silver it can be trickier and sometimes even really difficult. Many times, a DNA-test is the only way to be completely sure if the cat is agouti or non-agouti when we deal with these colors.

Below are two red cats, on the left a red classic tabby and on the right a solid red.

 Keilir 8veckor 11 Lilleman 8v 06 
 

Agouti – Here you can clearly see that the cat is light in the ears and the edges of the ears, it has so called glasses (the bright markings around the eyes), and are also light around the mouth. An agouti is also brighter under the stomach, and you can look in the back and will see that the cat is light around the anal o up in a string on the underside of the tail.

 

Non-Agouti – Here you can see instead that the cat is dark in the ears and around the ears, the marks around the eyes are there but are not white, only slightly brighter than the basic color, as well as the mark around the mouth and under the stomach. A non-agouti is evenly colored on the underside of the tail and around the anal.

 

In conclusion, i will take some examples of the inheritance of the trait.

In this example, we have a mother who is homozygous agouti and father who is agouti but carrier of the non-agouti.

Father
A

Father
a

Mother
A

AA

Aa

Mother
A

AA

Aa

As we see above, all kittens will be agouti (you will remember above that agouti is a dominant trait and it is only required that the cat has one gene for it to appear). 50% for homozygous and 50% for heterozygous (agouti, carrier of non-agouti).

In this example we instead have both mother and father who are heterozygous, agouti and carriers of non-agouti.

Father
A

Father
a

Mother
A

AA

Aa

Mother
a

Aa

aa

Here the odds have changed a lot, 25% will be homozyot agouti, these in turn will never be able to get an non-agouti offsprings. 50% will be agouti but will carry the trait for non-agouti. And finally 25% will be non-agouti.

In this example, we have a non-agouti mother and a father agouti and carrier of non-agouti.

Father
A

Father
a

Mother
a

Aa

aa

Mother
a

Aa

aa

As you can see above, we have gained another distribution, 50% will be agouti, carriers of non-agouti and 50% will be non-agouti.


So, we'll take one final example to make it really clear. Both mom and dad are non-agouti.

Father
a

Father
a

Mother
a

aa

aa

Mother
a

aa

aa

In this last example, we can see that all offspring will be non-agouti, there is no agouti-gen to be inherited. So all descendants will be non-agouti, therefore two solids can never ever get an agouti offspring.

 

By: Malin Sundqvist

Dilution 

Ok keep in mind, the basic colors are still black and red. Dilution is a trait that "bleaches" the color so that black turns blue and red becomes cream (just for fun we might call it the chlorine-gene because it is easier to think about bleaching in conjunction with chlorine right).

In order for a cat to be diluted, dilution must be inherited from both sides, the cat must, therefore, have a double set of the dilution gene for it to be visible dilution. 

Dilution is recessive and can be worn for many, many generations without appearing. For simplicity, we use the genetic designation diluted instead of printing the colors blue and cream.

Normal color = DD
Normal color and carrier = Dd
Diluted = dd

D/D

The cat is not diluted nor carries the dilution trait, no offspring after this cat will be diluted but they will become carriers if the other party is diluted or might be if the other part is a carrier of dilution.

D/d 

The cat is not diluted but carries the trait and can give diluted offspring with a diluted cat or another carrier.

d/d

The cat is diluted and, together with another diluted cat, will not give anything but diluted offsprings, although if the other cat is not a carrier, all offspring will become carriers, no offsprings will be diluted themselves. With a normal colored carrier, the offsprings can be diluted or normal color.

 

When trying to find out whether a cat is red or cream, you can not look at how bright the cat is, especially if it's silver involved. The difference between a red and cream is not the brightness but the shade. A red cat goes against orange, a warm color, while a cream goes against the blue side and has a dirty tone, like beige (sand). Most often, it is easier to see when the cat is newborn before, for example, silver began to break up properly.

Below is a litter with three red and a cream, you clearly see the cold sandy color in the fur, while the red ones have a more orange warm color.

20080304 Krafla4Ungar 01



Below is the difference between a Cream tabby and a Red Tabby. Here you can also see how incredibly difficult it can be to really see if a Red / Cream is patterned or not.

Maya (the cream-colored one) Looks non-agouti if you look at the edges of the ears, around the mouth and eyes., But she did get agouti-kittens mated with a non-agouti male. So we do know she is in fact agouti. Photos can also fool the eye a whole lot so trying to determine on color on photos can really be a challenge. Krafla to the right has very clear white agouti markings, but due to the light on this photo, they do not look very clear at all! She just looks vividly lighter around her eyes, in the ears, and around her mouth.

GimletsHimalaya

MittklattensKrafla

Gimlets Himalaya - Cream classic tabby

Mittklättens Krafla - Red classic tabby



IMG 6365

7v Svinto 03 1

Dagdrivarn Kelmaa - Blacktortie classic tabby

Dagdrivarn Trance Gemini - Bluetortie classic tabby

 

Some examples of the inheritance of dilution:

Below are examples of two diluted parents, so both mom and dad are blue or cream.

As we see from the table, all offspring will be diluted as both mother and father have a double set of the dilution trait,  anything else is not possible.

Father
d

Father
d

Mother
d

dd

dd

Mother
d

dd

dd

 

Hereinafter we have instead of the example where mom is not diluted (black/red) nor carrier of dilution, while daddy is diluted himself, ie blue or cream.

Here we can see that all kittens will be carriers of dilution but no one will actually be diluted itself, so if you have a male or female who is not a carrier, you can mate with blue or cream in infinity, but you will never get any offspring who is blue or cream.

Father
d

Father
d

Mother
D

Dd

Dd

Mother
D

Dd

Dd

 

We take one last example, both parents are full color (red/black) but carries dilution (blue/cream)

Father
D

Father
d

Mother
D

DD

Dd

Mother
d

Dd

dd

In the example above, we see that 25% of the kittens will be full-color and will not be dilute carriers (DD). We can see that 50% of the kittens will be full-color but will be carriers of dilution (Dd) and 25% of the kittens will be diluted themselves (dd).

 


Patterns

Ok then, let's talk about all these patterns. We know that the base colors are black or red. We can add on the dilution trait to bleach these to blue or cream and we have the agouti trait that determines whether the cat's pattern should be displayed or hidden. (Remember here all cats have a pattern even if we do not always see it).

The patterns we have on Maine Coon are:

Classic tabby, Mackerel tabby, Spotted tabby or Ticked tabby.

Classic Tabby

mcmc

Recessive (double genes are required for the pattern to be displayed).

Mackerel Tabby

McMc

Dominant

Homozygous Mackerel

Mackerel Tabby

Mcmc

Dominant

HeterozygousMackerel carries Classic Tabby

Spotted Tabby

Sp

Dominant

The gene breaks up the basic pattern to dots.

Spotted Tabby

sp 

Gen that does not break the pattern in dots.

Ticked Tabby

T

Dominate over all the other patterns but are located in a separate locus. This means that a ticked cat can also carry another pattern.

Ticked

t

Non-ticked

 

Here it will be a bit difficult when we begin to think of inheritance. Patterns are inherited as everything else in pairs, which means that a mackerel tabby can have one trait for mackerel tabby and one for classic tabby, which means that two mackerel tabby, if both are carrying classic tabby, actually can get offsprings who are classic tabby if the mc gene is inherited from both parents. Two classic tabby, on the other hand, can never ever get anything but classic tabby.

In the case of spotted tabby, there are two variants, one who believes be the one who gives us the cats that are mackerel tabby on one side and spotted tabby on the other. This is thought to be the ones who have mackerel tabby as a base pattern, while those who are very clearly spotted tabbies are those who have classic tabby as a basic pattern. How good the dots are, have nothing to do with whether the cat is heterozygous spotted or homozygous spotted.

The ticked tabby can be ticked in two different ways, either with several short breaks on the hair or with a few longer "on and off" (the hair will not become multi-banded ticked). Abessinier and Somali are homozygous ticked and have genotype TT while most other breeds with ticked cats have genotype Tt, heterozygous ticked, of course, we can by mate ticked with ticked also get homozygotes ticked on other breeds with ticked such as our Maine coon.

Below is a table where Cat 1 is heterozygous ticked but is also a carrier of both mackerel and classic tabby. Cat 2 is a mackerel but also a carrier of classic tabby.

 

Cat 1→

Cat 2↓

McT

Mct

mcT

mct

Mct

McMc Tt

McMc tt

Mcmc Tt

Mcmc tt

Mct

McMc Tt

McMc tt

Mcmc Tt

Mcmc tt

mct

Mcmc Tt

Mcmc tt

mcmc Tt

mcmc tt

mct

Mcmc Tt

Mcmc tt

mcmc Tt

mcmc tt

 

It's a bit tricky and you have to think a little, but hopefully, you understand the principle in any case, so in the example above it will be. 

If you see above, then we see that 50% of the offspring will be Ticked tabby.

About 37.5% will be Mackerel tabby and 12.5% will be Classic tabby.

Some examples of patterns and genetic combinations:

McMc Spsp tt - The cat is homozygous mackerel with the spotted gene that breaks up the pattern in spots.

Mcmc Spsp tt - The cat is heterozygous mackerel with the spotted gene that breaks up the pattern in spots.

 

McMc spsp tt - The cat is homozygous mackerel without the spotted gene, therefore Mackerel Tabby.

Mcmc spsp tt - The cat is heterozygous mackerel without the spotted gene, therefore Mackerel Tabby.

 

mcmc Spsp tt - The cat is Classic tabby with the spotted gene that breaks up the pattern in spots.

mcmc spsp tt - The cat is Classic tabby without spotted genes, therefore only Classic Tabby.

 

For example, everyone will be visibly ticked but carrying a few different other patterns.

McMc spsp Tt - Ticked cat that also carries homozygous Mackerel Tabby, no spotted

Mcmc spsp Tt - Ticked cat who also carries Mackerel Tabby, as well as carrying Classic tabby, no spotted.

mcmc spsp Tt - Ticked cat who also carries Classic tabby, no spotted.

 

In addition, we can play a little with agouti, too, all cats showing their patterns (apart from red and cream, if you remember what was included in the article about basic colors).

 

 aa mcmc spsp Tt  - Non-agouti, does not show its pattern.

Aa mcmc spsp Tt  - Agouti, shows its pattern, but is a carrier of non-agouti.

AA mcmc spsp Tt - Homozygous Agouti, shows its pattern and all offspring will be agouti.

 

By: Malin Sundqvist
Dagdrivarn (www.dagdrivarn.se)