Recessive Red (the "e" influence)

Ah, the beautiful Irish Setter. Also commonly known as the 'Irish Red' breed of dog, this breed is a particularly good example of recessive red the 'e' series. Firstly, I will point out a few things so we can establish what series the colour is produced from. We already can see this dog is not black, nor blue. We may think it is a dark shade of the brown dilution gene, however - if we remember correctly, brown dilutes are dilutes all over. Notice carefully that these dogs have black noses, dark eyes and eyerims. They are still genetically black, and not a dilute. Now we will look at the "e"/"E" series. If this dog was dominant "E" (red seen, black hairs present - i.e. sable) it would be fairly easy to find black tipped hairs on the body. It is well known that Irish setters come in red and red only. If they were indeed sables, chances are a few tanpointed patterns would appear every now and then. We know for a fact this never occurs in the 'red' breed. This rules out any form of agouti expressions. Therefore, these dogs would be "KK" ("BB" & "DD also.) Now we will look at the "E" series. "E" dominant E is the Red/Black expression only when agouti is present. As we know, these dogs are not any form of agouti. Therefore, they are the recessive expression of E. ("ee") This homozygous pair of recessive 'e' means that the body colour is recessively coloured independantly to the black colouration. Therefore, any "ee" in any phenotype means a red dog. Or, in some cases, whichever shade of red is present. This is how we get 'blonde and white' Border Collies or true 'fawn/cream' Kelpies - when the colour is not as strong as dark red, but still expresses on the recessive red series.
Now to explain how the black works here. Because we established that red is only a coat colour (this is the expression of phaomelanin, not eumelanin) the skin, eyes, nose and eyerims are not changed. Thus, if our dog is "KK" "BB" "DD" - he will have black in all of these areas. (Hence our black-nosed Red Setter.) If our dog is genotypically "bb', for instance, he will have a chocolate coloured nose and skin, and red or cream/lighter body.

Example of the nose leather of an Irish Setter dog. Its body is very deep Red, however the nose is stark black. The eyes are also dark. We have established this is due to two colourations being expressed - "KK" for the black, and "ee" for the red.

Another breed well known for its colouration is the Golden Retriever. This breed comes in one colour only; with the exemption of the actual colour coming in a variety of shades. This breed is an excellent example of a breed of dog that expresses this recessive red principle. Golden Retrievers are cream, gold, or sometimes near-white. As no black or forms of black are present, we know this breed is therefore "KK" "ee". We also notice that most Goldens have dark black noses, etc, with the exception of  a few chocolate/brown based dogs.

The same influence at work - this 'blonde' Border Collie is another example of the recessive red influence. Because there are no black hairs at all, this dog is obviously a recessive red. It also expresses "KK" as can be seen by the black nose. This dog is "KK" "ee".

An example of a true fawn, or 'cream' Australian Kelpie. This dog is recessive red and does not express any forms of tan pointing, dilute fawn, or blue. This dog may be similar in colour genetics to the breed's forebearer, the Dingo. Recessive red "ee", which is most likely the majority of Dingo expressions, is easliy dominated by dogs carrying "E" - hence why when bred to black/pointed dogs the cream colour became reduced in the genepool.
This colouration, a light, sandy coloured red is often called 'Fawn' (the true term for this shade of red) and is determined by the same influence which determines the colour of a dog's tanpoints if they express that pattern. Recessive reds do not express any form of agouti. (No sable, no tanpoints may be expressed. If they are, the dog is not recessive red, but rather, dominant red.)

Red (the "E" influence)

Now is when it gets a little more confusing. We have already discussed one 'red' influence (which is not genetically red, but rather diluted brown), and the black "K" factor. Now we will look at dominant "E" Red and its forms of expression. One thing to make note of here - dominant "E" Red works only with homozygous recessive "k". In other words, any "E"s on this influence will only be expressed if the genotype is "kk". Any "K"s, and the coat colour will revert to being a form of Black or its dilutes.
"E"s on this influence work alongside the agouti factor, which I will discuss in further detail on that post. The point I am attempting to make here, however, is that one cannot be expressed without the other.

Here we have a 'Red with Black Sable' or 'Black Sable Red' Dachshund. This terminology is correct in that, genetically, this dog is black over red. Any form of sable means that the hairs' base colour is red, with tipped black on the end. Sable is not what is known as 'recessive red', and is also part of the black series. It can be hard to understand exactly what this means, but I will try to simplify. Dominant "E" means red expressed with black (sable) if there are two "kk"s expressed. Otherwise the dog will be black, or a dilute form of this colouration. The sable that is expressed is obviously reliant on the agouti series. If the tanpoint pattern is dominant instead, no red can be found. Red sables are only present with 'A^y' - dominant over tanpoints. More on this later, when we reach the agouti influence.
To understand this explanation a little more, read the following post on recessive reds. This explains the difference between these two colours. Put simply, recessive reds express red and only red. No black hair may be found on the coat. Dominant reds are a form of black and red combined, and are genetically different. Recessive red "ee" overrides everything, including black. Dominant red can only be expressed with two homozygous "kk's.

An example as to how this influence works in recessive and dominant form, as explained above. Red sable works with the agouti expression ("A^y"), black recessive "kk" series, and dominant Red/black "EE" series. In some cases, only one "E" ("Ee") is required - sable will still be expressed.

Another example of a Red (in this case 'Fawn) Sable coloured dog.

This Great Dane, although appearing Fawn, is obviously also expressing black, in this case - in the form of the 'mask' as can be seen on the face. This dog is 'Fawn with Black Sable and Mask' - Black being the base colour, which is expressed on the "E" influence. The mask gene is expressed here also.
Any form of masking is a good indicator the dog is Sable - as recessive reds do not express black.

Here we have another Sable coloured dog, a Kooikerhondje. This breed comes in Red/Black Sable only (with White pattern) as can be seen clearly by the black tips on the ears. On Sables, the pattern can be very slight, or very extensive, as in German Shepherds. Sable will be discussed in greater detail in our Agouti series.

'Fawn' (the "b" & "d" influences combined)

 This post looks at the previous series of influences in their dilute forms ("b" and "d"). What we will look at now is the interesting colour that is expressed when these two dilutes are combined (or both recessives are present) on a dog. The only phenotype where this happens is "bb" "dd".

First, we'll revise these colours quickly. Using the Australian Kelpie as an example, we can first see the dilute brown series "bb" and its effect on the colouration of the dog. As previously discussed, we note that all black pigment is diluted to brown.
Here we have a diluite 'brown' dog, also called Red and Tan in Kelpie language. All black pigment is diluted to brown, and we now know this dog's phenotype to be"bb". The dog may also be carrying "d" - in which case, this dog could produce a combined dilute.

The next Kelpie here [pup] as we see, is a dilute black of the next series. He is diluted in a different way - the black is turned to a grey/blue colour. This dog, as we discovered previously, is "dd". It may also be a cariier of the above series, and its phenotype may be "Bb". Now is when our genetics get interesting. We now come across the unusual and hard to come by colour, 'fawn' (or blue fawn). This colour is actually falsely labelled and is not, in any way, a fawn colouration, nor is it affected by the same alleles that produces red Dachschunds or cream Golden Retrievers.

Here we see two examples of these 'fawn' coloured dogs. Both mother and pup here are the same colour. Put simply, this version of 'fawn' or 'blue fawn' is the result of blue and brown dilution genes working together. (It might be easy to imagine the two above dogs, red and blue, bred together. They would produce the dilute fawn colouration.) This colour could be called a double dilute, which it is in various terms, but it is actually a combinational dilute where two recessives work to combine and produce a different product. The phenotype of a dilute 'fawn' is always "bb" dd".

As with the other two dilute black series, this multiple dilution also causes the lack of melanin to be created in the coat. We can see here the eyes and nose of a Doberman of this 'fawn' colouration, and, looking closely, can notice that this dog's skin and colour is particularly lighter than even the light brown dilutes. This is apparently because there are two genes in dilution here, not just the one. This dog also posseses very lightly coloured eyes, and as with blues, these may come in amber, green or even blue. The eyerims are also quite light - a common health problem with this colour is that these animals are affected by bright sunlight - due to the lack of protective pigment around the eye. We make note, again, that despite this dilutedness, the tan points still have not changed! Again, this is the result of a different influence and it is not uncommon to have some fawns a similar colour or even lighter than their points!
In some breeds, this colouration is referred to as 'Blue Fawn', 'Fawn', 'Isabella'; and, in the Border Collie it is known as 'Lilac'.

Here we have an example of a 'Lilac' Border Collie. It is not quite chocolate, not quite fawn either, yet is a beautiful colour. The reason this colour is often referred to as Lilac is because these dogs often appear to have a 'purple' sheen. There are various theories on why this is so, but a common thought is that while the genes combine, they can have a tendency either way, and it appears to be chocolate with a little blue coming through - hence the purple term. 

Here is another Border Collie, only this puppy displays tan points. These points are quite light, making them almost invisible when compared to the coat colour. Note the almost pink nose and blue eyes as can be seen on this dog, typical of the dilutedness. We can establish that because this dog has tan points, it must be "kk" - it is also a dilute of brown and blue, so it is "bb" "dd".

Now, let's look at genetics.

Here I have included a simple example, which is not always the cause of this colour pupping up. Still, here we have a punnet square using a blue dog bred to a chocolate dog. (This is merely an example, obviously there are many more combinations possible.)This type of breeding is often deliberate and with the intention of breeding this colouration.

Here is also an example of one way this colouration is produced. (Note - this punnet square is not nearly big enough to show all possible offspring, but one gets the general idea as to how these offspring do come about.) It is often rarer to have a 'fawn' or 'lilac' dog produced from obviously black parents. The reason this happens is because both parents carry a set of the dilution gene which is only expressed when both sets match up. Apart from these expressions, it is also common for parents carrying these dilute genes to throw blue and chocolate pups. So, just quickly: dogs with genotype "Dd" Bb", "dd" Bb", "Dd" bb" bred to another carrying this dilution will produce isabella puppies.

Blue (the "d" Influence)

While we just looked at "D" in dominant, Black form, now we will look at a recessive form. The recessive expression of the "D" (dilute) series is a colour well known as 'Blue'. This colour is also often described as 'grey' and is, put simply, a diluted form of Black. What differs to our diluted Black-to-Brown colouration is the end resulting colour. The dilute blue series is separate to the dilute brown and while they do work together (later to be discussed) generally we see one expressed over the other.

Here we see a beautiful example of a 'dilute Black' (Blue) Pit Bull Terrier. It is very apparent that the coat colour is simply 'a light shade of black' - perhaps as one might describe the colour grey. Blue dilute dogs range in shades of dilute black and some, darker coloured Blues may often be hard to distinguish from blacks, except when in certain lights. Most Blues, however, are a similar shadeas can be seen in our Pit Bull.

Another thing this photo depicts is the whole body dilution that can be seen - in the same way a "b" diluted dog is chocolate-coloured pigmented. Dilute Black 'Blue' results in all pigment being diluted, which causes the blue colour. (As can be seen.) This means that coat colour, nose, eyerims and eye pigment is also affected (diluted).

Here is an example of how the 'blue' dilution also affects the eyes. Note the lack of dark pigment around the eyerims. As well as this, the eye pigment itself has also been altered. It is not uncommon for a Blue coloured dog to have amber, green, and sometimes, blue eyes. Darker colours are obviously only as dark as the coat's melanin allows. The nose (as can be seen in the first photo) is very similar in colour to the coat. Sometimes it may appear as though the dog has a shade of 'purple' to the coat. This is for a few different reasons, explained later. One important thing to quickly make note of - genetically, blue dogs are not, ever, "bb". They can indeed carry the browning gene, as well as express it alongside the blue dilute gene, however - this actually changes the appearance of the colour and is refferred to as a separate colour.

Here is a dilute Black ('Blue' - as we will now call them) Great Dane. Similar to the Great Dane used in the previous post, this Dane does have one obvious difference - its coat colouration. This Dane is expressing the dilute influence, which means its phenotype will be "dd". As we established Great Danes rarely carry chocolate, we can now establish its phenotype is: "KK" "BB" "dd". This dog is a carrier and expressor of Blue.

Just to illustrate the distinct differences between a dominant Black dog and a dog with the dilution gene, here is a photo of two Doberman Pinschers. It is apparent which is which. The blue dog is very obviously blue, with the distinctly diluted nose, fur, skin and eyes. Notice though, that the tan points are just as red as the other dogs. This is because this form of red is not affected by black. More on that later.

More Dobermanns! These puppies also express the dilution gene. One thing to note, here, is that they are all littermates, and that it is possible to get blue puppies from non-blue (Black) parents. These, of course, must each have one set of the dilution gene ("d") for this to occur. These blue puppies will be "dd", and the other puppies a combination of "Dd" (carrier, not expressor), or "DD" (dominant Black.)

Another Doberman. This dog, as the above Dobies, is also Blue. Now let's look at the possibly phenotype for this dog. Because this dog is expressing tan points, as do all Dobies, we know it is "kk" (tanpoints are expressed on 'k'). The dog may be either "BB" or "Bb" as red is common in this breed. It is also "dd". So, we have established our phenotype is now: "kk" Bb" "dd".
Blue Dobermans, as other blue dogs, are known for having skin and coat conditions. This is caused by the apparent lack of pigment (melanin).
Blue coloured dogs also appear to have coats that do not shine, and, isntead, may seem to have a dull or soft coat.

A pair of Blue Lacey's. We can see that this puppy is clearly blue ("dd") and has no tan points. ("Kk") The dog sniffing it is a red dog, however it is not affected by the "B" influence. This dog is actually Red Sable, which is affected by the "k" (agouti) series - to be discussed further on.

Here I will quickly include some examples of dogs falsely thought of as 'blue'. This dog, a Rough Collie, is what one might describe as 'Blue, Tan and White'. The Tan and White part it correct, however, this dog is actually "DD" and does not express the dilution gene. Despite its coat looking blue, it is genetically Black and White, modified by the merle gene. Despite this, these dogs are still called 'Blue Merle.' Note, however, the dog's nose and eyerims - dark black. This is not a blue dog.

One more example - a Stumpy Tail Cattle Dog. A separate breed to the ACD, this colour is also describes as 'Blue' by many people/ This is actually false, as there is not one blue hair on this dog. The Australian Cattle dog is "DD" and affected by what is known as the roaned/ticking gene, as well as expressing extreme piebald (a large expression of white). What this means is that the ACD is a black and white dog genetically, and appears blue because the hairs mingle together with varying degrees of darkness. It is basically an extremely ticked dog.


And there we have - the blue/black dilution influence. Next we will look at what happens when the recessive Brown ("bb") and recessive black/blue ("dd") genes are combined, and the colouration effects of this process.

Black III (the "D" influence)

Now to another Black influence. This influence follows the previous suit of "B" Blacks and dilute modifiers. In this case, the "D" series is also subject to the forms of Black dilution that can be seen.
Here we have yet another Black coloured dog. The point of me using this dog as an example is not simply because he is black. This dog comes from a breed that we know carries one of the forms of Black dilute. Not red/liver, Great Danes rarely come in chocolate. (I am not even sure that colour is in the purebreed genepool!) So that rules out any form of "b". This dog is actually a potential carrier of "d", our next series of Black dilutes. These dilutes are what are known as 'Blue'. Yes! This is where the unique and beautiful colour blue comes into play - a colour which ranges from dark black to gostly grey. This colouration is often misunderstood and mis-labelled.
So, looking at our dog here, we are focusing on the Black "D" and how it also affects the expression of the black coat colour. As we have discovered that black is dominantly expressed because of the "K" series, we have also learnt that it is expressed through the "B" brown series. It is also expressed through the "D" dilute (blue) series. We have also discovered that the genotype/phenotype for a dominantly black dog, such as our Labrador, is "KK" "BB" "DD". This dog is dominantly black in all three areas. If we have "kk" instead, the black is then affected by the "B" and "D" series. In case of "bb", we will have an expression of brown dilute colouration, but it is the expression of black of a "kk" dog which is most interesting. Now, let's have a look at our Great Dane here. As he has no expression of any form of agouti (tan points, sable, etc) he is "KK". We have also established the Great Dane as a breed does not express "b" Brown colouration, and therefore does not carry it either. This makes the phenotype so far "BB". Lastly, as the Great Dane often comes in dilute Blue of the "d" series, we can estimate that our dog is possibly a carrier of this expression, despite being solid Black. Thus, his phenotype may be "Dd". - Or,  "KK" "BB" Dd".

Red (the "b" influence)

Now we will elaborate on the brown, or red colouration from the "B" series. Red (as we will call these dogs from now on) is influenced by the absence of dominant "B", therefore it is expressed as "b". ("bb") As any dogs containing "B" will be black, these red variations are always "bb". Any form of "b" is also known as 'dilution' - therefore "b" is known as the brown dilution gene. In effect, this means that all forms of black on our dog are diluted to a lighter colour - a shade of brown. The result will be predominantly the same colour.

The dog you see here is a Chesapeake Bay Retriever, and is affected by this brown 'dilute' gene. It is recessively "bb" and cannot express or produce any black colouration whatsoever. This is demonstrated by viewing the dog's nose, eyerims, skin, coat, and eye  colour itself.

Here is an example of a 'red' dog's nose colouration. As the entire base colour is now diluted black, every extension is the result of this dilution. The nose is almost the exact colour of the coat and contains no black. Nose colour such as this is often termed 'liver' and is quite prone to suffer from natural effects such as sunburn.

Here is an example of the same kind of diluted colouration - and its effects on the eyerims. Note the clear black rim is no longer present, making the eye also more prone to sun problems.
Here we make a note of the fact that black is the base colour and that, because of this, any alterations to the black alter the entire colouration aspect. This is true of eye colouring as well. Because this dog is affected by the dilution of black to brown, the dark brown eye has also been changed to a very light, rich amber. The pigment is lessened and as a result a startling change in colouration has occured.

Now I will include some examples of variations of this colour dilution.

Dark Red - as seen in this Australian Kelpie - is often described as 'liver' and is the darker end of the scale of red black dilutes. This particular shade is close in darkness to black itself, however it is very apparent that this dog posseses no black pigment. (Nose and skin colour being indicators.) Our dog is not affected in any way by any other patterning, and is basically genetically a solid black dog - but with dilution.
Thus, its phenotype would be "KK" "bb" - because it is obviously brown and does not have any black colouration at all.
Or, our dog could be "Kk" "bb", because Kelpies often come in tanpoint patterning.

Here we have a beautiful example of a 'liver and rust' Doberman Pinscher. Its colour is slightly lighter than that of the above dog, however is still distinctly dark. The dog possesses the same pale nose and brown skin, as well as lightly-coloured eyes. (Green or amber.) This dog, however, has an added pattern of tan points. These points are a dark colour tan, but are not affected by the black gene.
Because of the expression of these tanpoints, the dog's phenotype would be "kk" "bb".
There are no exceptions here.

Now we have the example of a light brown Border Collie; this colour as seen is often called 'Red and Tan'. The dog possesses the liver nose, brown skin and lightly-coloured eyes of a brown dilute dog, and has no visible black. Its red shade is particularly light and this colouring is combined with the tanpoint pattern. The difference between this dog and the above is merely in the shades of colour. The white is affected by a differemt influence, so I shall not include that here. Thus, this dog's phenotype would be "kk" "bb" - again, no exceptions.
These variations in shade also cause some dogs, like this one, to have points a similar colour to or darker than its overall body colour. 

This Border Collie expresses a beautiful dark red/liver colouration as does the above collie; it, however, does not express tan points. Because of this, we can assume this dog has at least one "K" and is therefore "KK" or "Kk". As tanpoint is common enough in Border Collies, it is likely "Kk."
This dog shows the same diluted colouration of skin, nose, eyes and coat.

 These adorable puppies are seemingly all red. Yes, that may be the visual colour, but they are actually geneticallt vastly different and will throw different offspring. The three dark brown pups are dilute blacks. As we know, this is caused by "bb". The three 'red' pups are actually black nosed. Their redness is affected by a different influence entirely. They are actually "BB" or "Bb". This will be explained in greater detail further on.

Ah, some more puppies to look at. I added these two simply to show the variety in shades of red/brown and how their colouration is similar in contrast to the 'rust' of their tan point pattern.
These puppies may darken with age, but they will likely stay that beautiful earthy colour for life.
Their phenotypes would be "kk" "bb".
No alterations.

One thing I will quickly mention now is genetic inheritance. Because these dogs are "bb", a recessive factor, they are not always common. In some breeds, like Labradors, they pop up as a result of planned breeding, but in some breeds the colour being produced from seemingly black coloured parents can come as a surprise. This is, obviously, due to the recessive factors matching up ("bb") and remaining hidden in parents. It is often difficult to tell if a dog is "Bb" if it is always bred to "BB". If, on the off chance, a dog is bred to another "Bb", the breeding may result in a red/liver coloured offspring. The percentage, in theory, is 25% "bb", 50% "Bb", and 25% "BB". (75% black.) If one of these chocolate dogs was bred to "Bb" - chocolate carrying black - they would have red/liver offspring. If our red/liver dog "bb" is bred to a dominantly black dog "BB", no coloured offspring would result. This is explained in the labrador punnet squares.
Next we will look at Black III ("D") and black in its second dilute form: Blue.

Black II (the "B" influence)

Next in the genotype we have "B". "B", or 'brown', is another altering factor of dogs expressing black. This 'browning' factor is the part that is affected when you see a chocolate Labrador. This alteration I will explain further in detail. Here I will give a brief explanation. As in the example of the punnet square Labradors, we began with a genetically homozygous "BB" dog (that is, solid black), which was then bred to another homozygous dog. This dog, however, was not dominant black, but rather, recessively so. This dog's genotype was "bb". This "bb" is the execption to dominant blacks on this influence. Any "B" ("BB" or "Bb") results in a dominantly black dog. When no "B" is present, the colour is actually expressed as 'brown', 'red', or 'liver'. All are shades of red and range greatly.
But back to our original phenotype. Our dog, case #1 Black Labrador, has been established to have "KK". He is also homogynous for "BB". Because of this, our dog is not chocolate, nor will he ever have chocolate offspring. Any resulting offspring will all be Black. Our dog's phenotype so far is: "KK" "BB".

Here is our 'chocolate' Labrador. This dog expresses the result of the alleles "bb". Distincly different to our dominant black Labrador, this dog is still similar in shade, despite being brown. There are some distinct differences though, which will be further discussed.
We can establish that this dog's phenotype is "KK" "bb" - "KK" because no agouti patterns are present (agouti patterning plays on the 'k' influence) and "bb" because there is no dominant, black producing "K".