By Christine Lupo
By Christine Lupo
A recessive gene is one that is phenotypically expressed in the homozygous (two copies of the same allele) state, but has its expression masked in the presence of the dominant when heterozygous (one copy of the recessive and a copy of the dominant). Blue (b) eyes are recessive to brown (B). A blue eyed person has an allelic group of bb; whereas, a person with brown eyes can have either BB, homozygous dominant brown, or heterozygous, Bb, brown carrying blue. A recessive trait is one that must be contributed by both parents in order to appear in the offspring. My mother has blue eyes. My father has brown. My eyes are blue because I received one gene from each parent that were recessive for blue. Dad carried the recessive gene but did not express, or show it. Recessive traits can be carried in a person's genes without appearing in that person.
Traits are characteristics that you possess and show. You may have brown eyes and I have blue eyes--those are traits. My genes decide that I have blue eyes and your genes determine that you have brown. These genes are made of alleles. Alleles consist of one, or two, or more alternative forms of a gene that arise by mutation and are found at the same place on a chromosome. The genes for blue eyes are shown as "bb" because they are recessive. Brown eyes that can be shown through genes, or the genotype of BB or Bb. The uppercase B means that it is a dominant trait that will overpower the recessive and will show in the host. The allele is either B or lower case b. The gene combination of the Bb, BB, or bb and the trait that is shown either blue eyes for bb, or brown eyes for Bb or BB. This can be seen in cats, as well, in regard to coat color.
Seal, or Black, (Allelic group of BB [pure seal] or Bb [seal carrying chocolate]) is the dominant color of Ragdolls. Blue(genotype of BBdd [pure blue] or Bbdd [blue carrying chocolate]) is the dilute of Black. Chocolate is the recessive of black (genotype of bbDD [pure chocolate] or bbDd [chocolate carrying dilute]). Lilac is not an inherited gene, but is the dilute of the already recessive chocolate (genotype of bbdd). It is the total dilution of two recessive chocolate genes.
The "traditional" ragdoll that most people recognize is a medium haired, blue-eyed kitty with a pale body, dark face, ears, legs and tail and is described as being "pointed". This coat color pattern is the result of the RECESSIVE Siamese gene (cs) and it requires both parents to carry this gene in order to pass it on to their offspring. This is a recessive gene in the cat and therefore to have a cat with "points" the kitty must have two copies of the cs gene. Pointed traditional Ragdoll cats are produced by parents with the genotype of cscs. So, if both Ragdoll parents are cscs, then 100% of the kittens will be traditional. A traditional cscs cat bred to a cbcs mink Ragdoll will produce 50% traditional kittens. A combination of cbcs, or two mink Ragdoll parents mated, will produce 25% traditional kittens. A solid (Ccs) Ragdoll to a traditional (cscs) will produce 50% traditional kittens. A solid (Ccs) Ragdoll bred to a mink (cbcs) Ragdoll will produce 25% traditional kittens. With only one, or no copies of this gene, the cat will have pigmentation over the whole body and is considered a "solid" colored cat (CC or Ccs).
When Ann Baker bred Josephine to create pointed kittens, along with solid kittens, the female had to possess the colorpoint gene (C cs) and the father did as well. The father of Daddy Warbucks HAD to be either a solid carrying the Siamese gene (C cs), a mink (cscb), or a pointed (cscs) cat.
What Ann clearly states is that Blackie and Daddy Warbucks are both sons of Josephine, but with different sires. In the IRCA booklet it would appear to indicate that Blackie's father was a 'black cat from the East', that appeared 'more Persian than Burmese'. During detailed questioning, Ann confirmed that no-one had ever seen the father of Daddy Warbucks, and he was the only kitten in that particular litter of Josephine's. (Wallace, et. al.).
According to Blanche Herman, a breeder who initially worked with Baker, stated that Ann Baker bred both Persians and Apple Head Balinese cats and would use both in her program, as indicated in letters from Baker to Herman. Persians can be solid, as well as pointed, and can exhibit the bicolor pattern. Balinese cats are for the most part blue-eyed pointed cats, in traditional and mink, that have been known to produce mitts. Perhaps, Baker left the true history of the parents of the kittens a mystery on purpose. The amount of time, rumination, and prediction spent upon her highly publicized claims certainly provided a massive amount of commentary (free advertising) and made her cats both well known and sought after over the course of almost fifty years. The following is from the Ragdoll HIstorical Society:
It is important to note that the light side/dark side designation had nothing to do with coat color. Ann Baker claimed that the light side cats had a little longer noses and longer sharper ears like the Balinese. The dark side cats grew to look more like the Himalayan with a broader face, shorter ears, stockier build etc. Ann claimed that others looked like the sacred Cat of Burma and that the 7th generation Ragdolls would all look like Kyoto who was a seal mitted as was his father, Daddy Warbucks. Ann believed the light side cats were wonderful pets and seemed to have a little more of the desired disposition than the dark side cats. Ann felt that you needed to breed one from each side to get that real Ragdoll look.
Ann Baker claimed that she bred only seal Ragdolls for the first 7 years. However, she contradicted this by writing that the first lilac (which was actually a blue) was Thumper Jr. born 4/27/69. So how did Ann get the lilac/blue? She claimed that she got them by using a reversal process with the original mother, and from this a beautiful true lilac color was developed. This process was so successful, that the same process was tried on the dark side of the original three, and a black point was developed. She claimed that there would never be a blue or chocolate point.
You have to keep in mind that when Ann started working on developing the Ragdoll breed, she was at the time working with her black Persians and apple head lilac Balinese. In two letters sent to Blanche Herman she told Blanche about her experimental lilac program using her apple head Balinese. Later she claimed to Blanche that someone had stolen all her lilac Balinese because they thought that they were getting Ragdolls. She said that 95% of the lilac experimental program that she was breeding were born with kinks in their tails. She asked Blanche not to tell anyone about her outcross program to bring in the lilac color. She felt that the lilac/blue Ragdolls were on the extreme light side. She claimed that in her conflict with the Daytons her lilac program was her ace in the hole. (Pearce 2011).
Based upon both history, and simple genetics, the "Traditional" pointed Ragdoll cats would not be in existence without the foundation of solid cats and/or minks. They were produced from recessive genes, and mutations, or an abnormality, at that! To outright refuse to acknowledge them as the foundation and part of the Ragdoll breed is both preposterous and absolutely unconscionable. To be extremely specific, the pointed coat color pattern is recessive and is an error in the production of the enzyme tyrosinase. Point coloration in cats is a form of partial albinism resulting from a mutation in tyrosinase, an enzyme involved with melanin production. The mutated enzyme is heat-sensitive; it fails to work at normal body temperatures, but becomes active in cooler areas of the skin.The Tyrosinase (TYR) gene, also known as the Color gene, produces an enzyme that is required for melanin production. Mutations in TYR have been associated with temperature-sensitive pigment production that results in colors known as Burmese and Siamese. As a result, dark pigment is limited to the coldest areas of the body, that is, the extremities. Pointed kittens are born white, since the womb is uniformly warm. As the kitten ages, the cooler areas darken while warmer areas remain cream to white in color. Points are not limited to solid colors or dark colors. It is possible to have a red (orange color) or fawn (pale warm gray) point. It is also possible to have a tortoiseshell or tabby point. This coloration is also called pointed.
Again, this Siamese pointed gene is a dilution gene, meaning that an error has occurred in the responsible gene (the dominant albino C gene) that interferes with the ability to produce pigment. This is an interesting mutation in that the chemical reaction that allows for the production of the final pigment product, is dependent upon the temperature of the environment. The extremities of the cat’s body (ears, tail, paws, scrotum in males), typically, have a lower skin temperature than skin that is located over the heat-generating muscle masses. The ability to produce the normal compliment of color pigment is inhibited by the increase in skin temperature over the muscle masses of the body and effectively dilutes coat color.
This dilution gene also interferes with pigment production in the iris of the eye. With a minuscule amount of pigment in the iris, the cat's eyes appear blue. Solid colored cats do have normal amounts of pigment present in the iris and, therefore, DO NOT have the same blue eyes expressed in pointed cats. There is a separate gene that can cause aqua eye color in solid cats, but this is not the same "blue" that is seen in a pointed cat. Because of this restriction of pigment, pointed cat's eyes are always some shade of blue, because the top layer of the iris is not covered in another color, letting the blue show through. The back of the eye also lacks pigment, giving these cats' pupils a red reflection in the dark, unlike a normally pigmented cat's green to copper shine.
Traditional Ragdoll cats, like the nontraditional Ragdoll cats, inherit the genes for producing a specific amount of pigment, or melanin, in their eyes. Traditional Ragdolls carry the Siamese gene mutation, so they do not have enough pigment to achieve green to the rich copper colored eyes of their counterparts. The eyes of all Traditional Ragdoll cats have only tiny amounts of melanin, so their eyes are saturated with light that cause them to appear blue instead of exhibiting coloration or pigment. Their eyes, therefore, appear pale blue to deep cobalt blue.
It has been a great mystery, how certain Traditional Ragdoll breeders produced Traditional Ragdolls with such deep, intense blue eyes, especially since they are breeding recessive genes to recessive genes. Based upon Dr. Cris Bird's research, those breeders are either keeping solids in their basements to breed with their traditionals, or they have cats who have inherited underlying hidden genes for green eyes--the least melanin rich eye color in the cat. Once again, in either situation, those traditionalists should be thanking their bloodlines that trace to solids, at the very least, and acknowledging them at best!
In Dr. Bird's article, "Siamese Eye Colors from Whitish Blue to Navy Blue," he states the following, which also applies to Ragdolls with the Siamese colorpoint gene:
Siamese cats carrying hidden genes for copper eyes will produce melanin in larger trace amounts than Siamese cats carrying hidden genes for green eyes. The Siamese cats with hidden copper genes will therefore scatter more white light in their eyes.Their eyes will look very pale, whitish blue. Siamese with hidden green genes will have very deep, dark blue eyes. Siamese cats with the right mix of hidden genes for eye colors such as chartreuse, yellow, or gold will end up with blue eyes that are intermediate in color between whitish blue and navy blue. Now look at the full spectrum of possible blue eye colors...picture in your mind's eye another spectrum from green to yellow to gold to copper. That green to copper spectrum of the domestic cat underlies the navy blue to whitish blue spectrum of the purebred cat. The same genes are behind both spectra...the Siamese mutation greatly reduces the amount of pigment produced in the eyes, allowing light to fill the eyes instead, and that shifts the eye color spectrum from green/copper to whitish navy blue/whitish blue.
In Robinson's Genetics for Cat Breeders and Veterinarians, this is confirmed. "The deepest blue eyes in pointed cats are a result of the pigment reducing effects of the albinism allele combined with a low inherent amount of pigmentation; thus, full colored cats from lines producing exceptionally deep blue eyes in pointed offspring, are more likely to have green eyes" (Shelton, et. al. 135). It will be interesting to see what my yellow-eyed solid girl will produce with a traditional male, whom has no contractual restrictions and comes with permission to utilize in my nontraditional program!
Sepia and Mink Genetics
A second mutation at this same C location is referred to as the sepia or burmese gene (cb). Phenotypically, it is characterized by the same color dilution as with the cs gene. However, there is not as profound a sensitivity to skin temperature and therefore the body coat color is darker and much closer to that of the points. An "additive" relationship exists between the cs and cb genes. What this means is that when an animal is heterozygous for cs and cb (known as mink), the coat color expression is halfway between that of a point (cscs) and a sepia (cbcb).
The point gene is carried on the C locus, where pure albinism is also carried. It is shown with the sign cs, and needs two alleles of cs for the points to be expressed. Also carried on the C locus, is the gene for the sepia pattern. This is the darkest of all of the pigment restricting patterns, and pigment is only paled at the warmest point in the body--the abdomen. This pattern's gene is represented by cb. When a cat carries the genes cs and cb, the mink pattern is formed, in which the pigment distribution is between a sepia and a point cat.
The wild type phenotype is full color. The Burmese phenotype results from reduced pigment production changing black pigment to sepia and orange to yellow. The Burmese points are darker than the body and the eyes are yellow-gray or yellow-green. The Siamese phenotype reduces pigment production to the points and the eyes are blue. The wild type (C) allele is dominant to Burmese (cb). Burmese is incompletely dominant to Siamese (c); Burmese and Siamese heterozygotes (c/c) are intermediate in color (mink). UC Davis’ Coat Panel tests identify carriers of Burmese (also called sepia) and Siamese pointed coloration. A very rare allele of TYR produces an albino phenotype with white coat and blue eyes. The current tests do not detect this rare form.
Results are reported as:
C/C: Full color, cat does not carry Burmese (sepia) or Siamese alleles
C/cb: Carrier of Burmese (sepia) color
C/cs: Carrier of Siamese colorpoint restriction
cb/cb: Burmese (sepia)
cb/cs: Mink, intermediate color between Burmese (sepia) color and Siamese pointed phenotypes
For additional information on the genetics of coat color/patterns in cats, please consult the references given below and visit Dr. Leslie Lyon’s web page The Lyons' Den.
Non-Traditional Ragdoll Felines
This consists of seal, blue, chocolate, lilac, and the four newly introduced colors of CINNAMON, FAWN (Cinnamon's dilute), RED (Flame) and CREAM (Flame's dilute). Any cat with Cinnamon, Fawn, Flame, Cream, or Tortie in its pedigree has to have an outcross to another breed somewhere along the line, as Red was introduced in the 1980s and Cinnamon in early 2000. Any Ragdoll that has a LYNX pattern has also been outcrossed somewhere along the line to get the Lynx pattern. The pointed areas of the cat will display distinct barring, or Tabby markings, that is separated by lighter background color. The Lynx markings appear with ANY of the three patterns (bicolor, mitted, and colorpoint) and in all colors. If a Ragdoll female has a Tortie coloring, as well as Lynx markings, she will be identified as a Torbie.
Minks, Sepias, and Solids are not registrable in all cat associations. They are not currently accepted for championship in North America. Many Ragdoll clubs do not allow breeders of this variation to join or advertise their non-blue eyed kittens. The Minks, Sepias, and Solids may be registered and shown, however, in TICA, ironically, under “New Traits.” Minks, Sepias, and Solids (that are not blue-eyed white) do not adhere to the breed standard of multiple organizations and clubs, which state that a Ragdoll is a blue-eyed pointed cat. This was, and is, the written standard initially created and commercialized by the Daytons who PURCHASED blue eyed Ragdolls from Ann Baker, a business woman in a "man's world", a cat breeder, of the 1960s. The Daytons, and a group of their followers, dismissed Ann Baker's vision of her Ragdoll and made it their mission to establish a small representation of the Ragdoll breed, the "traditional" blue eyed variety, in the various cat fancier associations and show halls. Ann Baker, the pioneer and ORIGINATOR of the Ragdoll breed, bred Buckwheat, a Burmese cat in appearance, to Daddy Warbucks that produced kittens carrying the Burmese and pointed genes. These Ragdolls, Pointed, Minks, Solids, and Sepias, trace back to the ORIGINAL Ragdolls--Raggedy Ann Daddy Warbucks, Josephine, Blackie, and Beauty.
Yet another group of breeders, followers of Curt Gehm, who PURCHASED cats from Ann Baker chose not to honor contractual agreements with her and decided to outcross to other cats in order to produce these colors and patterns. This group took the remnants of what the Daytons left behind, in regard to Baker's Ragdolls, and promoted them as a "new" breed in the Cat Fanciers Association (CFA) calling them "Ragamuffins." They are not permitted any outcross. The breed standard for Ragamuffins is very different than that of the Ragdoll. The following information is in the Ragamuffin breed standard:
HEAD: the head is a broad modified wedge with a pleasingly rounded appearance, with no obvious flat planes. The forehead and top head should be moderately rounded. Muzzle is short and rounded, tending to broadness. The chin is firmly rounded, reflecting a proper bite. There is puffiness to the whisker pad, which results in the characteristic “sweet look” of the RagaMuffin. Cheeks are full. In profile, there is an obvious nose dip, giving the impression of a scoop rather than a break.
EYES: large, walnut shaped and expressive, moderately wide set, the eyes contribute to the characteristic sweet look. A slight oriental slant to the eye is acceptable. The more intense the eye color, the better. All eye colors are allowed.
COLOR: every color and pattern is allowable with or without white, except pointed colors. Any amount of white is allowed, e.g. white spots on paws, back, chest or belly; a blaze, a locket, etc. The degree of symmetry whether in the pattern or the white spotting is of no importance. Nose leather and paw pads are accepted in all colors and in any color combination, not necessarily related to coat color, listed colors are preferred, not required. Cats with white on feet may have pink paw pads or they may be bi-colored or multi-colored.
Colorpoints, Solids, and Mink Ragdolls have been in existence and registered with both IRCA and TICA, as can be seen in the photos below, and can be traced back to the ORIGINAL Ragdolls--Raggedy Ann Daddy Warbucks, Josephine, Blackie, and Beauty.
(Special thanks to Rovena Parmley [Tuftytoes] for providing these authentic, official documents and for giving permission to utilize these, and much more, to educate the public on this website and at cat shows. Click to enlarge photos).
Like the Cinnamon, Red, Tortie, and Lynx Ragdolls, after breeding to true Ragdolls for three generations removed from the foundation cat, these felines are able to receive SBT (Studbook Tradition) designation and recognition as a Ragdoll in TICA. One needs only to LOOK AT THE LINES IN A PEDIGREE to determine the origin of a Ragdoll—whether the Ragdoll in question is a descendant of the four Original Ragdolls OR outcrossed to produce the Mink, Solid, or Sepia. Breeders have produced Ragdoll cats that are not pointed, and with various eye coloration, just as Ann Baker did from the very beginning of the breed.
Dr. Maxine Stiles, a veterinarian and geneticist, and Sharon Steadman of Lattedolls, introduced the cinnamon gene from an outcross of an Abyssinian into the Ragdoll breed. After many generations, Dr. Stiles was granted her first SBT registration papers from TICA, in 2007, for Dollnouveau Dr. Pepper. A cat's "phenotype" is the way it looks and it's "genotype" describes its actual genetic makeup for particular pairs of genes. Julius Caesar's grandfather, Dollnouveau Cinnamon Sebastian, phenotypically is a Cinnamon Lynx Colorpoint Ragdoll, and genetically is b'b'Dd.
The cinnamon gene is a mutation of the gene responsible for producing black hair in the cat. An "allelic" group includes differing mutations of the same gene. In the cat, this particular allelic group includes black (B), chocolate (b) and cinnamon (b'). Black is the dominant form of this gene. Chocolate behaves as recessive to black, and dominant to cinnamon; therefore, cinnamon is the recessive to chocolate.
If a cat gets the dominant black form of the gene from one parent, then regardless of what came from the other parent, the cat will be black (BB, Bb, or Bb'). With no black gene, but with two copies of the chocolate gene, the cat will be chocolate (bb or bb'). The only way to see the cinnamon color, is for the cat to have two copies of the recessive cinnamon gene (b'b'Dd or b’b’DD).
With only one copy of the recessive cinnamon gene (Bb’ or bb’), a cat is considered a cinnamon carrier, that cat’s phenotype will not exhibit the cinnamon coloration, but it will have the ability to produce visual cinnamons when mated to a pure cinnamon with two copies of the cinnamon gene. A diluted cinnamon cat is a fawn. It takes three pairs of recessives to produce this coat color - cscs, b'b' dd. Several generations ago, Dr. Stiles outcrossed to a cinnamon British Shorthair cat to bring the Cinnamon gene into her recent litters of Ragdolls.
Hartwell, Sarah. "Eye Colors in Cats." 2009. http://messybeast.com/eye-colours.htm
Ishida Y, David VA, Eizirik E, Schäffer AA, Neelam BA, Roelke ME, Hannah SS, O'brien SJ, Menotti-Raymond M. 2006. A homozygous single-base deletion in MLPH causes the dilute coat color phenotype in the domestic cat. Genomics 88:698-705.
Lyons, L.A., Foe I.T., Rah H.C. and Grahn R.A. 2005. Chocolate coated cats: TYRP1 mutations from brown color in domestic cats. Mammalian Genome 16:356-366.
Lyons, L.A., Imes, D.L., Rah, H.C. and Grahn, R.A. 2005. Tyrosinase mutations associated with Siamese and Burmese patterns in the domestic cat (Felis catus). Animal Genetics, 36:119-126. See additional references cited in this paper.
Pearce, Wain. "Ragdoll History--Early Years." http://ragdollhistoricalsociety.org. 2011-2015 Ragdoll Historical Society (RHS). 15 August 2015.
Peter Schmitt, M., Grain, F., Arnaud, B., Deleage, G. & Lambert, V.. Mutation in the melanocortin 1 receptor is associated with amber colour in the Norwegian Forest Cat. Animal Genetics doi:10.1111/j.1365-2052.2009/01864.x
Robinson's Genetics for Cat Breeders and Veterinarians. 1999. Fourth eddition. Eds. Vells, C.M., Shelton, L.M., McGonagle, J.J. and Stanglein, T.W. Butterworth-Heinemann, Oxford.
Wallace, Lorna; Pickering, Robin, and Pollard, David. The Definitive Guide to Ragdolls. Ragdoll World. 1995 at Pontefract, West Yorks. England.