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                      Torties, Calicos and Tricolor Cats

Author

   Written by: Barbara French, Tarantara Cattery, Rochester, NY
   email: [e-mail]

   There is a lot of confusion about tricolored cats. This FAQ is meant
   to clear up some of the confusion, explain what is and what is not a
   tricolored cat, and how a true tricolor occurs.
     _________________________________________________________________

Table of Contents

     * [1]Are you going to throw a lot of jargon at me?
     * [2]OK, So what do you mean by a true Tricolor?
     * [3]Is it true that only females can be true Tricolors?
     * [4]OK, so there's a reason. Why?
     * [5]Oh, man. I knew this was going to get complicated!
          + [6]Basic sex inheritance
          + [7]The red or orange gene
          + [8]Males and the O gene
          + [9]Females and the O gene
     * [10]So how come there are some male true Tricolors?
     * [11]So male Tricolors are rare. Can I sell one for big bucks?
     * [12]What is the difference between a Calico and a Tortoiseshell?
       And what in heck is a Torbie?
     * [13]What are the possible color combinations?
          + [14]Why not?
     * [15]Can you wrap this up?
     * [16]So why didn't you just say so in the first place?
     _________________________________________________________________

Are you going to throw a lot of jargon at me?

   Well, I'm going to try not to. I believe in Plain English.
     _________________________________________________________________

OK, So what do you mean by a true Tricolor?

   Many cats appear to have three colors, but are not true tricolors.

   A true tricolor must have one of its colors derived from the red gene
   -- either red (orange) or cream (kind of a light, orangy beige, not
   unlike the color many people call "ginger"). If it does not have one
   of these two colors, it is not a true tricolor. The second color must
   be white, and the third color must be black, blue (a blue-gray),
   chocolate, lilac (a pale rose-beige), cinnamon, or fawn (a pale buff
   color). Black and blue are by far the most common.

   Some cats may appear to have three colors, but in fact may only have
   two. There is a designation called "bicolor" where the cat has a
   significant portion of white fur, but the rest of the cat is either a
   solid color such as black, blue, red, or a patterned color such as
   brown tabby, silver tabby (what many people call "tiger"), blue tabby,
   etc.

   A white cat with patches of tiger stripe might appear to have three
   colors -- white, black, and gray -- but because one of the three
   colors is not red or cream, it is not a true tricolor. It's defined
   (colorwise) as a tabby and white. A white cat with red or cream tabby
   patches is not a true tricolor either; only one of the colors may be
   red or cream in a true tricolor.

   In some rare cases, a Siamese-type pointed cat may appear to be a
   tricolor because of white patches on its body. These cats are
   mixed-breed, as significant white spotting is not found in the Siamese
   breed (although some small bits like a little white spot on the toes
   is found; this is considered a disqualification for showing). In this
   case, the cat is not a true tricolor either -- it's a seal point and
   white, or a blue point and white, or a chocolate point and white. The
   only exception to this is found in breeds such as the Himalayan,
   Colorpoint Shorthair and Javanese, which allows the points themselves
   to be tricolored (what are called "tortie points"). But that's a whole
   other story. On a pointed cat, if the points themselves do not include
   three colors -- white, red or cream, and one other color -- it is not
   a true tricolor.
     _________________________________________________________________

Is it true that only females can be true Tricolors?

   Yes, for the most part -- and very rarely, no. About one in 3,000
   tricolored cats are males, although only 1 in 10,000 of these males is
   fertile. There's a reason for this.
     _________________________________________________________________

OK, so there's a reason. Why?

   It's the nature of the genetics.
     _________________________________________________________________

Oh, man. I knew this was going to get complicated!

   No, wait! Don't go yet! It's really not that confusing. Just read.
   I'll keep it simple.

  Basic sex inheritance

   (boy, the word "sex" always gets people's attention!)

   Cats (along with humans, dogs, armadillos, weasels, mice, and other
   creatures) have two sex chromosomes. Chromosomes are the vehicles for
   genes, and genes define traits like coat color, fur length, eye color
   -- everything that makes the cat what it is.

   Sex chromosomes define gender. There are two sex chromosomes (stands
   to reason, what?), designated X and Y. Each parent contributes one sex
   chromosome, and these determine the gender of offspring. Females
   produce only X chromosomes in the form of their egg, but males produce
   both X and Y chromosomes, propelled in sperm. It's the male's
   contribution that determines whether an offspring is male or female
   (if only Henry VIII had known . . .).
        Females produce eggs:             Males produce sperm:

           *****        *****              ***         ***
          *  X  *      *  X  *            * X ******  * Y ******
           *****        *****              ***         ***

   These eggs and sperm also carry one half of the parent's genetic
   material, which explains inheritance. Eggs and sperm do not carry the
   same combination of genes, which explains why all of our offspring
   don't look identical to one another.

   When egg and sperm meet, they combine their traits to form a single
   entity, not unlike pulling two halves of a zipper together. They also
   combine their sex chromosomes.

   If an X sperm meets the X egg, they produce an XX, or a female.

   If a Y sperm meets the X egg, they produce an XY, or a male.

   (Since there is no such thing as a Y egg, no YY is possible.)
     _________________________________________________________________

So what does this have to do with Tricolored cats?

   I'm getting to that.

  The red or orange gene

   Unlike other coat color genes, the gene that determines red coloration
   can be carried only on the X chromosome. If you look at pictures of
   chromosomes (they look a bit like X-shaped breakfast cereal, with long
   arms), you will see that the X chromosome is normal sized in relation
   to other things, but the Y chromosome is smaller. It can't carry the
   gene that determines red color; only the X chromosome can do that.

   The gene that determines red or orange coloration in cats is
   designated as O (for orange).

     O = orange
     o = non-orange

   If the cat inherits an O pattern proper for its gender (I'll explain
   that in the following sections), the cat will be red or orange (I'll
   just continue to call it orange, even though most cat associations
   refer to this as red). This orange will cover up all other colors,
   except pure white. If the cat inherits an o pattern proper for its
   gender, it won't be orange.

  Males and the O gene

   Remember, however, that the Y gene can't carry the O gene at all --
   only X can. Males are genetically XY. The Y fires a blank as far as
   the O gene is concerned, so males only get one O gene -- from Mom. The
   designation for this "blank" is usually just written as Y.

   Male patterns:

     OY = orange cat
     oY = non-orange cat

   These are the only possibilities for an XY cat.

  Females and the O gene

   Females get one X from each parent, so they get two O genes.

   However, here's where things get exciting.

   In most genes, the capital letter designation is for dominant genes,
   and the small letter designation is for recessive genes. In most
   genes, if the cat gets one dominant gene and one recessive gene,
   whatever is the dominant gene will show up and the recessive gene
   won't actually appear on the cat. The cat is said to "carry" the
   recessive gene, which means s/he can pass it on to offspring.

   So by that rule, if the female cat gets one O and one o (Oo), she
   should be orange, right?

   Not with this gene.

   With the O gene, the O and o actually combine their efforts,
   displaying both orange and non-orange, along with white. This is
   called a mosaic. This creates the true tricolor -- the calico or
   tortoiseshell. You must have the combination of the O and the o to
   create this, which means the cat must have two genes. Since only Xs
   can carry the O gene, the cat must have two X genes -- or in most
   cases, be a female.

   Female patterns:

     OO = orange cat
     oo = non-orange cat
     Oo = tricolored cat
     _________________________________________________________________

So how come there are some male true Tricolors?

   The answer: genetic misfire.

   Sometimes, a male cat will get three sex chromosomes instead of two.
   This is a genetic anomaly. Genetics is all about pairs; you should
   only be able to have two of any genes, two of any chromosomes,
   residing in any individual. Although in some cases there are more
   genes than two possible for a given trait (like all the possible eye
   or hair colors on people), only two traits can actually sit there.
   It's sort of like owning a Geo Metro convertible: you might have more
   than two who want a ride, but you can only fit two in it.

   Well, sometimes, weird things happen in genetics, and you get an extra
   gene or chromosome in there.

   Sometimes, these duplications can have negative effects. For example,
   Down syndrome in humans is caused by a duplication of Chromosome 23,
   where there are three chromosomes instead of two. Animals are only
   meant to have a certain number of chromosomes; in this case, having a
   "spare" isn't good.

   In cats (as well as other creatures, including humans), sometimes
   there is an extra sex chromosome. Some can be invisible and never
   detected.

   A male cat who is a tricolor must have two X chromosomes to carry the
   Oo pattern. Thus, the cat must be at least an XXY. In humans, this
   pattern is known as Klinefelter's syndrome. One result of this
   syndrome is that the male has trouble with developing secondary sex
   characteristics and is usually sterile. However, unlike Klinefelter in
   human, an XXY male cat will usually not have any outward signs of its
   genetic makeup, unless it's a rare male tricolor.

   Although a male tricolor almost certainly sterile, you will still want
   to neuter such a cat to reduce such undesirable traits such as
   spraying and aggression.
     _________________________________________________________________

So male Tricolors are rare. Can I sell one for big bucks?

   Only to the gullible. They are not considered desirable in purebred
   breeding programs, as in some associations they cannot be shown or be
   used in breeding programs. They won't breed more male tricolors. There
   is not a significant market for them. Best just to neuter him and keep
   him as a beloved pet, or find him a good home.
     _________________________________________________________________

What is the difference between a Calico and a Tortoiseshell? And what in heck
is a Torbie?

   Goodness, a lot of questions there. :-)

   The difference between a calico and a tortoiseshell is this:

   With a calico, there is a significant amount of white, and the two
   colors are broken up into distinct patches. This has to do with the
   interaction of white spotting.

   With a tortoiseshell, the three colors are blended and don't form
   distinct patches. A tortoiseshell may have significant portions of
   white as well, but the remaining colors are blended (this particular
   pattern is called a tortoiseshell and white).

   A torbie, or patched tabby, is a tortoiseshell where the tabby pattern
   is very distinct all over the cat. A calico or tortoiseshell may have
   distinct tabby pattern on the red or cream patches (has to do with
   another gene we won't get into at this juncture), but no patterning on
   the other color. This isn't a torbie. A torbie is clearly patterned
   all over the cat -- though never on the white.
     _________________________________________________________________

What are the possible color combinations?

   First color is: white, always

   Second color is: red or cream

   Third color is: black, blue, chocolate, lilac, cinnamon, or fawn.
   Black and blue are by far the most common in domestic cat populations;
   chocolate is fairly rare, and cinnamon is almost unheard of. But
   they're worth mentioning. I'm not going to go into a lot of detail on
   the inheritance of black, blue, chocolate, lilac, cinnamon, and fawn.
   It's their relationship to the red gene that we're discussing in this
   FAQ. That's the subject of another FAQ.

   These colors combine in very distinct ways. You can't have a chocolate
   and cream, or a blue and red, or a black and cream.

  Why not?

   The answer: the dilution gene.

   There is a gene called the dilution gene which in appearance "washes
   out" a color and makes it a lighter version. In dominant form (DD or
   Dd), the cat is normal colored. In recessive form (dd) the cat's color
   is diluted.
        Color           Normal (DD or Dd)          Diluted
        black           black                      blue
        chocolate       chocolate                  lilac or lavender
        cinnamon        cinnamon                   fawn
        red             red                        cream

   If the cat is diluted, all its colors are diluted. If the cat is not
   diluted, none of its colors are diluted.

   So you can only have a certain number of possible combinations, based
   on the fact that you must have one color from each of the three, and
   you must have either all dilution or no dilution.

   Just a note: tortiseshells and their dilute counterparts may have
   very, very little white present. It's the combination of the red or
   cream with black, chocolate, or cinnamon that's important here.

  CALICO OR TORTOISESHELL PATTERNS, UNDILUTED*

   *patterns with black are just designated by pattern, not by color

   calico (black, red, and white patches)
   tortoiseshell (black, red and white mixed up)
   chocolate calico/tortoiseshell (chocolate, red and white)
   cinnamon calico/tortoiseshell (cinnamon, red, and white)

  CALICO OR TORTOISESHELL PATTERNS, DILUTED*

   *Dilute tortoiseshells are often referred to as (color)creams.

   dilute calico (blue, cream, and white patches)
   bluecream (blue, cream, and white swirls)
   lilac-cream or lilac calico (lilac, cream, and white)
   fawn-cream or fawn calico (fawn, cream, and white)

  TORBIE OR PATCHED TABBY PATTERNS, UNDILUTED

   brown patched tabby (brown tabby, red, and white*)
   *A brown tabby is genetically a black tabby
   chocolate patched tabby (chocolate tabby, red, and white)
   cinnamon patched tabby (cinnamon tabby, red, and white)

  TORBIE OR PATCHED TABBY PATTERNS, DILUTED

   blue patched tabby (blue tabby, cream, and white)
   lilac patched tabby (lilac tabby, cream, and white)
   fawn patched tabby (fawn tabby, cream, and white)

   And of course, you can have any of these "and white," except for
   calico, which already has significant white spotting from the gene
   that causes the "and white."
     _________________________________________________________________

Can you wrap this up?

   Sure.

   Cats who do not have one of the following combinations are not a true
   tricolor (although tortiseshells and their dilute counterparts may
   have a negligible amount of white):
     * Red, Black, White
     * Red, Chocolate, White
     * Red, Cinnamon, White
     * Cream, Blue, White
     * Cream, Lilac, White
     * Cream, Fawn, White
     _________________________________________________________________

So why didn't you just say so in the first place?

   Because without the explanation, you probably wouldn't have believed
   me.
     _________________________________________________________________


    Torties, Calicos and Tricolor Cats FAQ
    Barbara French, [17][e-mail]

References

   1. file://localhost/home/t/tittle/public-web/cat-faqs/tricolors.html#jargon
   2. file://localhost/home/t/tittle/public-web/cat-faqs/tricolors.html#truetri
   3. file://localhost/home/t/tittle/public-web/cat-faqs/tricolors.html#onlyfemales
   4. file://localhost/home/t/tittle/public-web/cat-faqs/tricolors.html#reasonwhy
   5. file://localhost/home/t/tittle/public-web/cat-faqs/tricolors.html#complicated
   6. file://localhost/home/t/tittle/public-web/cat-faqs/tricolors.html#sex
   7. file://localhost/home/t/tittle/public-web/cat-faqs/tricolors.html#redgene
   8. file://localhost/home/t/tittle/public-web/cat-faqs/tricolors.html#male-o
   9. file://localhost/home/t/tittle/public-web/cat-faqs/tricolors.html#female-o
  10. file://localhost/home/t/tittle/public-web/cat-faqs/tricolors.html#maletris
  11. file://localhost/home/t/tittle/public-web/cat-faqs/tricolors.html#bigbucks
  12. file://localhost/home/t/tittle/public-web/cat-faqs/tricolors.html#diffs
  13. file://localhost/home/t/tittle/public-web/cat-faqs/tricolors.html#colorcombos
  14. file://localhost/home/t/tittle/public-web/cat-faqs/tricolors.html#whynot
  15. file://localhost/home/t/tittle/public-web/cat-faqs/tricolors.html#wrapup
  16. file://localhost/home/t/tittle/public-web/cat-faqs/tricolors.html#sayso
  17. mailto:[e-mail]