| Red – The color range for Reds, includes all shades between cream and dark red. They can present minimal slight blue coloration that shows through.
Tri – Tri’s are Blue with Red markings on the points (Red points: over the eyes, on cheeks, under the tail around the anal area, and down the legs.) The Blue and Red markings are subject to the variation of shades of color that apply within those categories. Note: If a Tri looses, or is not born with the head dominantly blue, which gives a saddle back appearance, this needs to be documented, and reviewed before becoming part of the standard.
White Markings
White on the chest region can extend up to the chin and down on the underside of the torso to????. White on the toes can extend to what would be referred to as a white sock, but preferably below the “ankle” joint. Dogs may also exhibit minimal white hairs on the tip on the tail. White on the muzzle above the chin, the head, or the front legs higher than one inch above the “ankle’ joint and/or the top of the neck region is a disqualification for breeding purposes.
Note: There has not been a documented Blue Lacy born with excessive white on the back legs, which would reach above the hocks. However, all of these other white patterns have occurred within the breed, occasionally.
Science behind the “Predominately Solid or Solid with Points Color Appearance” and “White Markings”!
At the embryo stage of a canine’s development, special cells are involved in the formation of the central nervous system (the brain and spinal cord). These special cells, left over at the edge of the nervous system formation, then become know as Neural Crest Cells. Neural crest cells migrate throughout the body to form the melanocytes of the skin and much more. The gene that produces white patches on a dog is believed to interfere with the number of neural crest cells produced, or interfere with the neural crest cell’s ability to migrate. Yes, all this starts at time of embryo formation!
Where melanocytes are present, there is a potential for color to be produced. These melanocytes serve as a shielding function to protect deeper structures such as organs from harmful ultraviolet rays. Melanin is produced by the melanocytes, and is responsible for hair and skin color. White markings are the result of a lack of melanin “pigment” in an area.
In predominately solid color, or solid with points breeds, such as the Blue Lacy, most of their structure possesses an even distribution of pigment. When pigment is absent in an area, white patches appear.
Distribution of color in coat.
In this section I would like to refer to a good web page that already exists on the topic. The link provided directs you to the page that refers to the coat colors more associated with the Blue Lacy Breed.
http://homepage.usask.ca/~schmutz/dilutions.html
Here is the list of recognized color series in dogs:
A (agouti), B (brown), C (albino/chinchilla dilute), D (dilution), E (extension), G (graying), M (merle), R (roaning), S (white spotting) and T (ticking).
Color gene series possibly recognized in the Blue Lacy breed could consist of:
“A” (agouti) – Primary Coat Color – The Agouti series has three alleles that exist in this group. This series has multiple alleles, which influence the amounts of dark and light pigment in the hairs of the whole coat.
“B” (brown) – This color series has two alleles. Possible colors within this series, red dilute, and black which is lightened to chocolate. Nose leather color will be brown to chocolate in this series. Note: This is not prominent in the Blue Lacy, if seen at all.
“C” (chinchilla dilute) – This series has several alleles. Many believe there are more than the defined alleles commonly listed for this gene.
Suggestions of minor variants on the c-ch allele – “C” allows full pigmentation such deep reds, and blues. “c” suppresses black and red pigments to silvery gray and cream (off white).
Note: This series could be the reason for the variations of “shades” seen within the Blue Lacy breed, but that is undocumented at this time. This series does not affect nose leather color.
“D” (dilution) – The Dilution Series has two alleles. This series acts with other loci to cause different expression of the color genes, but does not actually cause color.
Note: This is believed to be the most common gene-effecting coloring seen in the Blue Lacy breed.
“E” (extension) – This series has two alleles.
Note: If there is a contributor to color for certain “Red” colored Blue Lacys, it would be the recessive “e”.                                     Extension gold, yellow and cream.????
“T” (ticking) – This series also has two alleles. – Flecks of color seen in white areas. This series in not always seen at birth, but can appear as a dog ages. The color that starts showing through the white will be the base color. In many breeds ticking can only change the skin color and not effect the color of the white hairs.
Note: This is possible with the Blue Lacy breed as well, but would be more of the skin color effect on aged dogs.
“S” (spotting) – The White Spotted series has four alleles.
Note: This gene is expressed in the Blue Lacy breed and the next section will expand on this.
“S” White Spotted Gene
Understanding the white spotted gene’s presence within the Blue Lacy breed is important. As mentioned above, melanocytes migrate down from the spinal column during the process of embryo formation. In dogs, it is not uncommon for actual “S” solid color dogs, otherwise Blue or Red in color, to have white toes, chest, or tip of the tail.
Some believe this can be a result of just a random event, other than the result of a specific allele. The random event would happen very late in the embryos development and prevent the complete distribution of the melanocyte to these areas. There are also beliefs, and speculation, that the rate of melanocyte distribution and migration itself may be inherited.
Studies indicate small amounts of white on the chest, toes, or tip of the tail; do not seem to be the cause of mutations in the MITF. You ask, what is MITF? MITF stands for Microphthalmia Associated Transcription Factor. It was one of the first genes that were identified, published in 2007, which causes at least some spotting patterns and/or potential mutations causing some forms of white spotting in coat color.
The major series of genes that distributes pigment in dog’s coats is called the “S” or spotting series. This series controls the amount of white markings expressed.
S – Solid color. Modifying factors – white on toes, chest and tip of the tail.
Note: This applies to the Blue Lacy Breed
si – Irish spotting – Definite Pattern – white on muzzle, chest, neck, legs and tail. Modifying factors control the amount of white seen. “Plus” factors extend the white and area, while “minus” factors reduce the white.
Note: This applies to the Blue Lacy Breed.
sp – Piebald – 50 % white covers most of body
Note: Not a factor in the Blue Lacy breed.
sw – Extreme Piebald – Produces an all white dog
Note: Not a factor in the Blue Lacy breed.
Charles Little (1957) implied that most spotting was caused by the four “S”alleles listed above. This does not fit with new DNA studies. Currently, Ojvind Winge (1950) does not assign alleles to the Spotting Series in his book. Mr. Winge states that there is a recessive allele that controls “white-mottling”, and when it is homozygous, the dog will exhibit more white. When the recessive allele isn’t present, he suggests the white markings are minimal, or not expressed. Minimal, is implied to be represented on the feet, tail tip and chest.
How should breeders look at breeding, concerning the excessive white guidelines?
During conception, reproductive cells of the parents unite replication type, which individual breed characteristics are transmitted through. Puppies receive half of their chromosomes from the dam and the other half from their sire.
Each individual Blue Lacy owner may have a certain look or white pattern they desire. Accountable breeders will only breed parents that conform to breed standards, and which exhibit good temperament, health, type, character, working ability and drive. A particular color, or the amount of white exhibited, within breeding standards, should be considered after all of the other traits.
Now, for the white spotted gene: Again, after all the main breeding traits are compared, if a breeder wants to reduce the risk of pups being born with excessive white, they should select a sire and dam which compliment each other. If a breeder feels that a sire or dam has a large amount of white present, but still within breeding standards, they should select an opposite sex Blue Lacy to breed this dog with, which has less white showing. However, this is not fool proof, being that there are many factors that play a role in pigment distribution.
There are documented litters where both parents have minimal white markings, and they still produce pups with excessive white coloration. There is also documentation of litters in which both parents have large white areas, although still within breeding standards, and all the pups exhibited less white than the parents, and in a different distribution on the body.
In talking dog breeds, coat colors, and markings, we can only describe what we see in front of us. We are looking at the dog’s phenotype, or the appearance of the dog. We cannot readily visualize the genetic makeup, which is called the genotype. Knowing there can be a difference in a dog’s phenotype versus his genotype, we can only do the best we can as breeders, figuring percentage and probabilities before a mating takes place.
Just because a litter mate, or mates, ends up having excessive white for the breed, that does not effect other pups in the same litter, which do not exhibit excessive white. Those pups were born with, and possess, the gene that expressed the distribution of pigment to meet the breeding standard. These individual pups have a high enough percentage rate of standardization to produce breeding standard pups, when bred to another dog meeting the standard.
Pups that would be classified as having excessive white are still just a much pure blood Blue Lacy as their littermates. There may be nothing wrong with their drive or abilities to hunt, and/or their ability to be a companion dog. There are several benefits to having these pups in Blue Lacy breeding. Many individuals looking to obtain a Blue Lacy are not interested in breeding. These individuals that plan on spaying and neutering, make great owners for pups that have excessive white markings. These pups with extra white, or pups which may not meet the standard for other reasons, can fill that slot, leaving more breeding standard pups in the breeding program. They can be as well liked, and loved, by their new owners, as a breeding standard pup would be from the same litter.
The white spotted gene will always be in the genetic make up of the Blue Lacy. Trying to breed it out, would not be conducive to maintaining the breed, or the standards by which the breed has always been identified.
The Greyhound also possesses the white spotted gene, but excessive white was not an issue for breed standards within Greyhounds. You can look at a Greyhound, no matter what color it is, and identify what breed it is by their body structure.
The only reason for having excessive white as a disqualification for breeding standard Blue Lacys, is to set it apart from other dog breeds, which share a similar body type, and which allow more white in their standard. Color and markings are maintained for breed identification purposes only.
There is much more information, and studies which have been done on Coat Color and genetics. This article expresses the author’s opinion, based upon observations and a thirteen-year study of coat color and genetics within the Blue Lacy breed.
It was written to help breeders be more aware of some of the color genetics within this particular breed. There are many studies and books related to this fields.
Below is a list of recommended research material.
Animal Genetic:
http://homepage.usask.ca/~schmutz/dogcolors.html
- Dog Coat Color Genetics, J. Chapell’s
http://abnormality.purpleflowers.net/genetics/index.htm
- Canine Coat Color – Inheritance and Appearance (coat colors and coat color inheritance in dogs) with an emphasis on colors in Borzoi, 1995 Bonnie Dalzell, MA, Version 8-21-97
http://www.borzois.com/coat.color/coat.color.html
Studies related to Diluted Coat Color:
Philipp U, Hamann H, Mecklenburg L, Nishino S, Mignot E, Schmutz SM, Leeb T. 2005. Polymorphisms within the canine MLPH gene are associated with dilute coat color in dogs . BMC Genetics 6:34-. (This article is published in a publicly accessible online journal at http://www.biomedcentral.com/1471-2156/6/34)
Studies related to the “White Spotted” gene:
Brenig, B., Pfeiffer, I., Jaggy ,A., Kathmann, I., Balzari, M., Gaillard, C. and Dolf, G. 2003. Analysis of the 5′ region of the canine PAX3 gene and exclusion as candidate for Dalmation deafness. Animal Genetics 34: 47-50
- Krempler, A., Breen, M. and Brenig, B. 2000. Assignment of the canine paired-box 3 (PAX3) gene to chromosome 37q16->q17 by in situ hybridization. Cytogenet. Cell Genet. 90 (1-2), 66-67.
- Metallinos, D and Rine, J. 2000. Exclusion of EDNRB and KIT as the basis for white spotting in Border Collies. Genome Biology (a web based only journal) online article
- Schmutz S.M., Moker J.S, Yuzbasiyan-Gurkan V., Zemke D., Sampson J., Lingaas F., Susana Dunner S., and G Dolf. 2001. DCT and EDNRB map to DogMap Linkage Group L07. Animal Genetics 32:321.
- Schmutz, S. M., T. G. Berryere, and C. A. Sharp. 2003. KITLG mapping to CFA15 and exclusion as a candidate gene for merle. Animal Genetics 34: 75-76.
- Zemke, D. and V. Yuzbasiyan-Gurkan. 1999. A single nucleotide polymorphism and a (GA)n microsatellite in intron 6 of the canine endothelin receptor B (EDNRB) gene. Anim. Genet. 30:390.
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