General Color Genetic Information

The Blue color in German Shepherds is the result of a dilution gene. This recessive gene dilutes any Black pigment on the dog including coat color, nose leather, foot pads, eye rims, and lips. It also affects their eye color. Most Blue German Shepherds have lighter colored eyes, including but not limited to, yellow, amber, and varying shades of light brown. When puppies first open their eyes they are colored blue. This is due to a protective film nature provides. Blue colored German Shepherd puppies often retain this blue eye color 8-10 weeks after birth which is much longer than a puppy not affected by this dilution gene. Below is a simplified explanation of the genetic activity which results in a puppy being born expressing the blue pigmentation.

*Note: This same explanation and mode of inheritance outlined below can be used for the Liver coat color as well as well as the pure White coat color. The difference between the Liver gene and the Blue gene is that the Liver gene blocks the formation of the black pigment entirely rather that simply diluting it. Further explanation of the differences between these two recessive color genes is explained further down. The White coat color is due to a masking gene and is unrelated to affecting black pigmentation as the blue and liver genes do. Further explanation of the White masking gene will be explained further down as well.

Two genes are at work in producing the coat color of a GSD:  a color gene and a pattern gene.  The pattern gene produces either the familiar saddle markings (which we will use here for ease of explanation) and facial mask markings.  Usually those markings are Black, and the most familiar pattern for a GSD is probably the Black and Tan Saddle pattern.  In a Blue colored dog, the recessive Blue color gene dilutes--acts upon--only the Black pigment on the dog.  As a result, a Blue dog can be, Blue and Tan, Blue and Red, Blue Sable, Solid Blue etc. To simplify the explanation below I am using the term "Blue" as a general statement to describe a Blue GSD of any pattern, and the term "Black and Tan" to describe a GSD of "normal" of coloration. Further down I will discuss the solid black pattern gene which is often mistaken as a color gene.

For a puppy to be born expressing the Blue pigmentation in a litter, both parents must carry this Blue dilution recessive gene. When the pups are developing during the gestation period they have a "choice" of color genes to choose from. Someone had told me to think of it as containers of paint. Let's say both the dam and the sire are Black and Tan in coloration. Each parent carries a gene for this color and shows it since this is a dominant gene. Now let's say that each parent also carries the Blue recessive gene. Since this Blue gene is recessive they will not show the color Blue but do have the ability to pass this it on to their offspring. So each parent has two "containers" (color genes) for the pups to choose from. That is a total of four color genes and each pup will only carry two. One from each parent. So let's say pup #1 chooses a Black and Tan gene from his dam, and a Black and Tan gene from his sire. This pup will be Black and Tan in coloration and will NOT carry the Blue recessive gene. Now let's say pup #2 chooses a Blue gene from his dam, and a Black and Tan gene from his sire. This pup will be Black and Tan in coloration but will carry the Blue recessive gene and have the ability to pass it on to his\her offspring should the dog ever be bred. Now pup #3 chooses a Blue gene from each parent. This pup will be a Blue. He is carrying a double recessive, or two Blue genes. So the pup will not only show the Blue color but pass on the Blue recessive to all of his\her offspring if it is ever bred.

Note that if two Blue adults are bred together they will produce an entire litter of Blues. The reason is there is no choice for the pups. Both parents carry two Blue color genes. Therefor they will grab a Blue gene from each parent causing them to carry the double recessive and be Blues themselves.

If a Blue adult dog is bred to a dog who is normal colored and does NOT carry the Blue recessive, then NO pups will be born Blue but ALL pups will carry the Blue gene. The reason is, each pup grabbed ONE gene for color from each parent. Since one parent was a Blue and carried two Blue genes, the pup has no choice but to pick up the Blue gene from it's Blue parent. Since the other parent was not a Blue, nor carried the Blue gene at all, he had no choice but to grab a normal colored or dominant color gene. So he will show the dominant normal colored gene but will carry the recessive Blue gene.

Interestingly enough many times Blue puppies are killed by the breeders. This was much more common years ago, but still occurs today with unsettling frequency. For each person there are many different reasons why this decision is made. Some breeders view their breeding as a business. Especially in Germany or other European countries, it is not uncommon for them to cull or kill a Blue pup so that it doesn't take away from the milk supply the other normal pups need to thrive. In certain countries there is a requirement by certain governing agency(s) that nursing litters do not exceed 6 puppies. The breeder will choose the six most promising pups and cull the rest. In countries where this is not a requirement blue, liver, or white colored pups are often killed as well. Some do it because they erroneously believe that the Blue dilution gene is a certain trademark of poor health and believe they are doing the pup a favor and sparing it a lifetime of suffering. Many others simply refuse to allow a fault to survive. Their reasoning may be, "Why keep this dog alive? It is a disqualification and will never achieve a conformation title or the papers needed to breed it." It is a waste of time and valuable resources for them to raise a puppy who is a serious or disqualifying fault, according to the breed standard, as far as they are concerned.

*As a side note the word "cull" can mean two different things. One is to outright kill the pup. The other is to simply spay\nueter the pup thereby effectively remove him from the breeding pool. What is ironic about this latter choice is that many breeders are unaware that many of this blue pups traditionally colored littermates ALSO carry this recessive but do not express it. They believed they were ridding the gene pool of this off color gene but in fact if any of the littermates are bred they too may be carrying the gene and passing it on to their offspring. Recessives can be passed on in this manner from generation to generation never coming out of hiding until a blue, liver, or white pup suddenly pops up seemingly out of nowhere when finally a dog who carries this hidden recessive is bred to another dog who also is secretly carrying this gene.

Still yet more reasons come to light as to why a breeder would kill an off color pup. One of which goes on today and is unscrupulous to say the least. In the highly political world of dogs and competition it is not unheard of for a breeder to kill a Blue pup that pops up unexpectedly and not tell anyone about it. Why would someone do this? Well these people may have spent several thousand dollars on a well bred pup and spent an enormous amount of time, money, and resources to achieve a championship title on their dog. Now they anxiously await the time to breed, they've spent large amounts of money on proper nutrition, health tests, etc. Excitedly they watch every health test come back clear. The perfect dog! They hunt down a perfect mate, perhaps shipping their bitch across country for the mating to occur. Now the pups come, and one is a Blue! Many breeders would find this an insult. "YOUR dog carries the Blue recessive?" Many other breeders may not want to breed their top stud or bitch to this dog in the future fearing that some of the pups would surely pick up this gene. (Which they would!) Since some don't understand the genetics of this they may automatically blame the other dog not knowing that it takes two with the Blue gene to create a blue pup! For instance they may say, "Well my stud has been bred to "X amount" of bitches and has NEVER thrown a Blue. It must be your bitch who carries the gene!" Perhaps this is the bitches first breeding. If both parties don't understand the genetics of this, the owner of the young bitch may choose to kill the pup and cover up the fact it was ever born. She fears having to spay her bitch or have it marked as a "carrier". Unbelievable as this sounds, it HAPPENS. Again the ironic part of this reasoning is that they usually don't realize that many of the pups in the litter who are normal colored also carry the recessive. They just don't show it. This recessive can be passed on through several generations unknowingly, until one is bred with another carrier and another "surprise" Blue pup pops up, seemingly out of "nowhere".

Unfortunately many myths surround this color variation. The largest one is about their supposed "poor health". Rumor and speculation always surround what is not understood, and Blue German Shepherds are no exception. This is yet another reason why someone would choose to cull a blue pup. Honestly believing that the dog is a genetic nightmare just waiting to happen, they'll choose to "put it out of it's misery" as soon as it's born. Unfortunately for the pups who are born to uneducated breeders, this is an unfortunate and irreversable occurance. As of this date no known medical problems directly related to the Blue dilution gene have been documented. This is not to be compared with problems plaguing Blues in other breeds. On the same note, stories of people who have seen ONE Blue pup that had health problems should not be used as proof that the Blue gene was responsible for those problems. The German Shepherd breed is plagued by a variety of medical conditions just like every other breed. If you saw one Black and Tan puppy who was plagued with medical problems, would you blame it on the fact that the puppy was Black and Tan in color?

The good news is many breeders are allowing these Blue pups to mature and selling them on a spay\neuter contract with limited registration or no registration at all. At least this is better than an instant death sentence!!!

Even better news is that more and more often now breeders are becoming more open minded about breeding for the "Total dog" without regard for something as minor as a color fault. If an off color dog is otherwise a fantastic representation of the breed and has so many good points that not breeding the dog would be a sin due to coat color alone, then why not? You could breed this off color dog to a dog of traditional coat color if you do not wish off color pups. The pups will be born with the strong genetic makeup of their parents and only be carriers of the recessive. Knowing full well the genetics behind coat color is a strong tool in planning your breeding program to produce the types of pups you would be proud to bear your kennel name.

The Solid Black Pattern Gene

One more often heard myth is that if you breed two solid Blacks they will surely produce Blue pups. This is not accurate as both parents STILL must carry the Blue recessive gene in order for this to happen. If one or both parents do not carry the Blue recessive gene then NO Blue pups will be born as a result of that breeding. The solid black gene is actually not a color gene but a pattern gene. There are solid blues and solid livers in the German Shepherd breed. The solid black or self coloring pattern gene does not affect coat pigmentation like blues and livers. Blue dilutes black pigment and Liver blocks the formation of black pigment. The solid black gene causes the dog to wear a solid black pattern. If a solid black dog is bred to a black and tan saddleback who does not carry the solid black gene the pups will be born whatever other pattern genes are floating around in the parents chromosones, but they will not be solid black. Solid black is another double recessive that follows the same mode of inheritance as outlined above regarding Blue pups. Since solid black is NOT a color gene but instead a pattern gene then it is possible for a dog to be solid blue or solid liver in color.

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Steel and Powder

We have discovered there are two distinct shades of Blue. What we have dubbed "Powder Blues" and "Steel Blues". This difference no doubt occurs due to modifiers present which act in conjunction with the dilution gene. As of this date the specific modifier that causes the Powder Blue coat color has not been identified. Prior to my litter being born we had theorized that Powder blues were the result of a dog expressing the blue gene and carrying the liver gene (but only one copy so it was not expressed in pigmentation) This theory effectively was blown out of the water when my steel blue bitch Gypsy gave birth to a litter sired by my Powder blue male Rebel which consisted of six pups. One powder blue female, two steel blue males and three Izabella (Fawn) colored pups. The Izabella, or Fawn coat color is a result of a pup carrying both the blue and liver genes as well as expressing them in pigmentation.

Steel Blue GSD's usually mature into a dog who is darkly colored enough to pass for a regular Black and tan when by themselves. However stand these dogs next to a "true" Black and Tan, and the difference becomes obvious. This darker Blue color represents a much larger portion of the Blue GSD population. Somebody once told me that Blues looked like a GSD who had been dusted in flea powder. I felt that was a very apt description of the color.

The second variation, Powder Blues, we believe carry modifiers that cause further paling of the coat colors. You can see the difference between Powder Blue and Steel Blues here. I had the opportunity to photgraph Rebel's dams' last litter (which is how I ended up falling in love with, and consequently coming home two weeks later with Rebel.) and was able to capture the difference between
Rebel and his other Blue littermates. As pups they already look different, but as adults they could never be mistaken for a Black and Tan as the adult Steel Blues often are. Powder Blues are much lighter, they are truly Grey and Tan from puppyhood to adulthood. While Steel Blue pups start out Grey (or rather Blue) and darken significantly as adults, Powder Blues retain the lighter color on their coat, nose leather, lips, etc. Renegade was often mistaken for a Wolf hybrid due to this and his startling yellow eye color. It is of course no secret that at the beginning of the development of the German Shepherd breed a Wolf was used to sire a litter and therefore Wolf hybrids became an important factor in setting the type for this breed.

The Liver Gene

The Blue gene is different from the liver gene in that it occurs in different areas in the chromosone (more specifically different areas of the loci) which means that a dog can carry both the blue and liver gene at the same time. By speaking with breeders who do choose to purposefully breed these colors we have learned a lot. Both of my males, Renegade and Rebel come from a dam who is a normal Black and Tan yet carries both the Blue and Liver gene. Obviously she carries the Blue gene as she has thrown Blue pups in previous litters. What makes her suspect for carrying the Liver gene as well is that she also had three Liver colored littermates and I believe she is the one who passed the liver gene onto Rebel as opposed to his sire Tecumsah as there is no record of livers in Tecumsah's pedigree. Those Liver colored littermates of Rebel's dam is a strong argument that she carries both the Blue and the Liver recessive. Both my males, Renegade and Rebel, are full brothers and both Powder Blues from different litters. I discovered Rebel carried the Liver gene when he sired a litter of pups with my Gypsy and three Izabella (Fawn) colored pups were born. You can see photos of this litter located here. Livers are also capable of carrying the Blue gene and if bred with another dog who carries blue and liver as well can produce Izabella (or Fawn) colored pups. We have also discovered a distinct difference in liver coat colors, also we suspect due to modifiers. There are livers who are a distinct reddish or Cinnamon type color and others are a darker Brown Chocolate color. Naturally as with any coat color there are varying degrees of shades involved in individual dogs due to fading modifiers and stronger pigmentation in some lines. I went to visit and photograph two Liver pups out of a litter of ten and the color difference was striking in the two pups. One was a cinnamon color, the other a lighter almost mocha color. Photo's of these pups can be seen on the Photo page in the Liver Gallery under the links "7 Week Old Liver Pups", pg. 1 and pg. 2 I wish I had kept in touch with that particular breeder now as it almost makes me wonder if this lighter pup was indeed an Izabella.

 

The Izabella\Fawn Coat Color

The Izabella, or Fawn coat color is a result of a pup carrying both the blue and liver genes as well as expressing them in pigmentation. Since the liver gene blocks the formation of black pigment all black pigment on the dog is now expressed as brown. Since there is no black pigmentation to dilute, the dilution gene dilutes the brown pigment instead. So genetically speaking a Fawn pup is a Diluted Liver. Since we know that both the Blue and Liver genes are each double recessives we can ascertain with much certainy that both sire and dam carried both recessive genes. Fawn pups are often referred to as double dilutes but since the liver gene technically blocks the formation of black pigment I feel this is an incorrect statement genetically speaking.

 

The White Coat Color

The White coat color is another recessive gene. This gene is a masking gene. This means that it does not dilute or block the formation of black pigment on the dog as the Blue and Liver genes do respectively. This color affects coat coloration alone and is NOT to be confused with Albinism which is a mutation that carries along with it detrimental health effects. A White coated German Shepherd dog is genetically not White, but it is masked by this gene. It is like covering up a burgandy couch with a white sheet. The couch is still burgandy in color but all you see is white. The same mode of inheritance applies to White coated GSD's as outlined above for Blues. You can learn more about White German Shepherds here.

 

See photos of Blue and Liver German Shepherds.

*The views expressed on this page are strictly the opinion of the writer Darlene. If you have information that can confirm or dispute anything you see here, please contact me. Also if you have any other additonal comments that you feel would be useful to this site please don't hesitate to contact me as well.

 

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