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► AKC Pomeranian Color guide 
Description: Pomeranian -AKC Color guide Below is a list of the colors and markings available for this breed. Please refer to the breed standard for descriptions and the difference in types.

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Added on: 01-Sep-2008
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► Breeding and showing Pomeranians of different color than orange? 
Description: Breeding and showing Pomeranians of different color than orange? A Little Spitz-Pom and Color History (Where Pomeranian Dogs were Different Color) The earliest written document about importing a pair of 'Pomeranian dogs' to England is dated from 1767. Pomeranian dogs were little Spitz dogs, that were commonly seen in the region of Pomerania (Pommern), that's why they used to be called "Pommern-Spitz" in German, - and Pomeranian in English. Older people still remember the little white Spitz dogs of Pomerania, - yes, white! The English breeders kept on decreasing the size of the Pomeranian dogs (a height limit of 28 cm had been determined at that time), and over the following decades the size and look of the little Pomeranian Spitz dogs changed to what is known as the Pomeranian today.

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Added on: 07-Jul-2009
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Rating: 10.0 (2 Votes)

► Canine - Merle Gene 
Description: Merle Coat Colour Patterning The merle coat colour is characterized by patches of dilute pigment in combination with areas of full pigmentation. Therefore, the merle gene acts to lighten whatever coat colour would otherwise be expressed. However, unlike other dilution genes, the lightening effect is not spread evenly over the coat, but is expressed as patches of diluted colour scattered over the dog’s body. If the basic colour of the dog is black, the effect of the merle gene is a soft gray, often referred to as “blue”. If the basic colour of the dog is red, the effect of the merle gene is a pale red. The merle coat pattern is characteristic of a number of breeds recognized by the American Kennel Club, including the Shetland Sheepdog, Collie, Border Collie, Dachshund, Australian Shepherd, and Cardigan Welsh Corgi. Genetic Inheritance of the Merle Gene It is only recently that investigators at the Texas A&M University (reference: PNAS, 2006, 103(5):1376-81) discovered a mutation in the dog SILV gene and found it to be responsible for the merle coat colour patterning in dogs. The merle gene (M) is inherited in an autosomal fashion. In other words, the trait is not linked to gender and can be passed on from either the mother or the father. The gene is incompletely dominant, or a gene that has intermediate expression. A heterozygous dog, carrying only one copy of the merle gene (Mm), expresses the characteristic diluted coat colour pattern. A non-merle dog (mm) is normal in colour, while a homozygous double-merle (MM) is predominantly white. Punnett squares can be used to determine the expected coat colour of offspring when breeding dogs of known genotype (i.e. coat colour genes have been identified). In the example illustrated, a non-merle dog (mm), indicated in the vertical column, bred to a heterozygous merle (Mm), indicated in the horizontal column, will give rise to offspring with an expected frequency of 50% merle (Mm) and 50% non-merle (mm). Dogs that carry the merle gene but do not show the characteristic merle phenotype, are known as cryptic merles. These dogs may give rise to merle offspring. It is suspected that the DNA sequence of the merle allele in the cryptic is shorter than the allele expressed in the typical merle dog. The harlequin coat colour pattern in Great Danes is produced through the interaction of the merle locus and the harlequin (H) gene. In harlequin Danes, the merle background colour is diluted to nearly white with fully pigmented black patches. Health Problems Associated with the Merle Allele Both heterozygous merle (Mm) and homozygous double merle (MM) dogs may exhibit auditory and ophthalmic abnormalities including mild to severe deafness, increased intraocular pressure, ametropia, microphthalmia and colobomas. The double merle genotype may also be associated with abnormalities of skeletal, cardiac and reproductive systems.

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Added on: 01-Sep-2008
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► Canine Color Genetics 
Description: Canine Color Genetics Dogs have a wide variety of genes that influence color. Further, the same genes may give a very different effect on different types and lengths of coats. While this site is primarily concerned with Shetland Sheepdog colors and a long, working-type (double) coat, I will use comparisons from other breeds and even other species whenever it seems useful. References, including other mammalian color genetics, are on a separate page. One of the biggest problems people have with genetics is the assumption that a defined trait - size, ear type, color, yappiness - is due to a single gene. In fact, genes code for two types of things. One, which is relatively well understood, is the structure of a particular protein. The normal equivalent of the albino gene, for instance, codes for tyrosinase, an enzyme which breaks up the amino acid tyrosine as a first step in producing melanin, the major pigment in mammalian skin and hair. In an albino, this enzyme cannot be produced, and as a result melanin cannot be produced. A second type of gene controls when and where other genes are turned on or off. These genes are the subject of vigorous ongoing study, and probably have a major impact on such things on the number of vertebrae in the spine or the age at which growth is complete. I've included a page which defines some of the terms used in genetics, as well as explaining dominant, recessive and incompletely dominant genes. Right now, let's look at some of the gene series (loci) known to influence canine color, and try to get a feel for what they do. Before starting our list, we need to know that mammals have two forms of melanin in their coats. One, eumelanin, is dark, though it can vary somewhat in color due to variations in the protein that forms the framework of the pigment granule. The base form of melanin is black. Melanin can also appear brown (often called liver in dogs) or blue-gray. The second pigment, which varies from pale cream through shades of yellow, tan and red to mahogany (as in the Irish Setter), is called phaeomelanin. There are at least two and possibly as many as four gene series that determine where, on the dog and along the length of the hair, eumelanin and phaeomelanin appear.

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Added on: 29-Apr-2008
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Rating: 7.0 (1 Vote)

► Canine Colours-THE WHITE SPOTTING SERIES 
Description: THE WHITE SPOTTING SERIES . White spotting on dogs is determined by the genes on the S locus. When we use the term "white spotting" we simply mean white areas, not actually white spots. White spotting can occur on any colour, and will cover up both eumelanin and phaeomelanin. So any dog can have white markings, whether they're black, blue, liver, isabella, brindle, sable, tan-pointed, merle or whatever. White hair occurs when the skin cells are unable to produce any pigment. The white spotting gene impairs the ability of cells on particular parts of the skin to make pigment, so the skin becomes pink and the fur white. Nails and paw pads will also become pink in areas where pigment is not produced. There are generally thought to be four alleles on the S locus, each causing different amounts of white. However, these do not seem to account for the huge variation in markings seen on dogs, so it's possible there are more which haven't yet been identified. The four that geneticists are pretty sure exist are:

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Added on: 01-Sep-2008
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► Dog Coat Colour Genetics 
Description: Dog Coat Colour Genetics

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Added on: 01-Sep-2008
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► Elementary merle genetics for newcomers 
Description: Elementary merle genetics for newcomers- This is and is intended to be a very basic explanation of the workings of the merle gene. If you already know about double merles and sable merles and such, you may not find anything new here, but you're welcome to stick around and comment. If you're not sure why people get upset about sable merles and double merles, stick around and learn. There is no such thing as a sable merle gene or blue merle gene. There is only a merle gene. Merle is a dilution gene, that is, it lightens whatever the coat color would otherwise have been. The lightening is not spread evenly over the coat, but leaves patches of undiluted color scattered over the dog's body. Also, the lightening seems to work primarily on the black pigment in the coat, so any tan on the face stays even. Note that "black" as used here includes liver or chocolate. These colors are rare color faults in Shelties, but everything written here applies also to other breeds with the merle gene, including Australian Shepherds. A red merle in that breed is produced by the merle gene acting on a liver (solid red-brown, not the same as sable) coat. One dose of the merle gene on an otherwise black dog produces a blue merle - a more or less bluish gray dog dappled with black spots. Tan points - the tan spots over the eyes, on the sides of the muzzle, on the legs and under the tail of a tricolor dog - will still be there in the merled tricolor. If the tan spots would not be present in a black dog, giving what is usually called a bi-black in Shelties, tan will not be present in the merled black either, and the dog will blue merle and white without tan: a bi-blue. One dose of the merle gene on an otherwise sable dog produces a sable merle. Sable merles are less predictable in color than blue merles, and may range anywhere from an apparent sable, often with a pinkish or orange cast to its coat, to something that looks like a very rusty blue merle. White markings remain on the merled dog, and may even be slightly more prominant.

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Added on: 29-Apr-2008
Hits: 334
Rating: 10.0 (2 Votes)

► Genetics of Coat Color and Type in Dogs 
Description: Genetics of Coat Color and Type in Dogs- a brief review of the genes controlling dog coat colors and patterns, as well as coat type

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Added on: 29-Apr-2008
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► HEALTH PROBLEMS LINKED TO COLOUR 
Description: HEALTH PROBLEMS LINKED TO COLOUR . There are a few colour genes which can occasionally cause health problems in dogs. The main problematic colour genes are the merle and dilution genes.

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Added on: 01-Sep-2008
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► Merle Pomeranians 
Description: Merle Pomeranians

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Added on: 13-Aug-2009
Hits: 474