Calico cat
A calico cat (
A calico cat is not to be confused with a
Derived from a colorful printed
Because the genetic determination of coat colors in calico cats is linked to the X chromosome, calicoes are nearly always female,[5] with one color linked to the maternal X chromosome and a second color linked to the paternal X chromosome.[4][6] In most cases, males are only one color (for instance, black) as they have only one X chromosome. Male calicoes can happen when a male cat has two X chromosomes (Klinefelter syndrome, with XXY sex chromosomes and generally they are sterile); the condition is a chimera, with two different cell types;[7] or, rarely, when some skin cells of the developing kitten spontaneously mutate.
Some calico cats, called "dilute calicoes", may be lighter in color overall. Dilutes are distinguished by having grey (known as blue), cream, and gold colors instead of the typical colors along with the white.
History
The tri-color coat characteristic of calico cats does not define any breed, but occurs incidentally in cats who express a range of color patterns; accordingly, the effect has no definitive historical background. However, the existence of patches in calico cats was traced to a certain degree by Neil Todd in a study determining the migration of domesticated cats along trade routes in Europe and Northern Africa.[8] The proportion of cats having the orange mutant gene found in calicoes was traced to the port cities along the Mediterranean in Greece, France, Spain, and Italy, originating from Egypt.[9]
The calico has been Maryland's state cat since 1 October 2001. Calico cats were chosen as the state cat because their white, black, and orange coloring is in harmony with the coloring of the
Etymology
The fabric called "
Genetics
In genetic terms, calico cats resemble tortoiseshells in most ways, except the tortoiseshell has a black undercoat and the calico has a white undercoat. One anomaly is that, as a rule of thumb the larger the areas of white, the fewer and larger the patches of ginger and dark or tabby coat.[14] In contrast, a non-white-spotted tortoiseshell usually has small patches of color or even something resembling a salt-and-pepper sprinkling. This reflects the genetic effects on relative speeds of migration of melanocytes and X-inactivation in the embryo.[15]
Serious study of calico cats apparently began in 1948 when
Calico cats are almost always female because the locus of the gene for the orange/non-orange coloring is on the X chromosome.[19] In the absence of other influences, such as color inhibition that causes white fur, the alleles present in those orange loci determine whether the fur is orange or not. Female cats, like all female placental mammals, normally have two X chromosomes. In contrast, male placental mammals, including chromosomally stable male cats, have one X and one Y chromosome.[4][16][20] Since the Y chromosome does not have any locus for the orange gene, it is not possible for a normal XY male cat to have both orange and non-orange genes together, which is what typically results in tortoiseshell or calico coloring.[18][21]
One rare genetic exception resulting in a male calico is when faulty cell division leaves an extra X chromosome in one of the gametes that produced the male cat. That extra X then is reproduced in each of his cells, a condition referred to as XXY, or Klinefelter syndrome. Such a combination of chromosomes could produce tortoiseshell or calico markings in the affected male, in the same way as XX chromosomes produce them in the female.[21][22]
All but approximately one in three thousand of the rare calico or tortoiseshell male cats are sterile because of the chromosome abnormality and breeders reject any exceptions for stud purposes because they generally are of poor physical quality and fertility. Even in the rare cases where a male calico is healthy and fertile, most cat registries will not accept them as show animals.[23]
As Sue Hubble stated in her book Shrinking the Cat: Genetic Engineering Before We Knew About Genes,
The mutation that gives male cats a ginger-colored coat and females ginger, tortoiseshell, or calico coats produced a particularly telling map. The orange mutant gene is found only on the X, or female, chromosome. As with humans, female cats have paired sex chromosomes, XX, and male cats have XY sex chromosomes. The female cat, therefore, can have the orange mutant gene on one X chromosome and the gene for a black coat on the other. The piebald gene is on a different chromosome. If expressed, this gene codes for white, or no color, and is dominant over the alleles that code for a certain color (i.e. orange or black), making the white spots on calico cats. If that is the case, those several genes will be expressed in a blotchy coat of the tortoiseshell or calico kind. But the male, with his single X chromosome, has only one of that particular coat-color gene: he can be not-ginger or he can be ginger (although some
modifier genes can add a bit of white here and there), but unless he has a chromosomal abnormality he cannot be a calico cat.[9]
Currently, it has been very difficult to reproduce the fur patterns of calico cats by cloning. Penelope Tsernoglou wrote that this "...is due to an effect called x-linked inactivation which involves the random inactivation of one of the X chromosomes. Since all female mammals have two X chromosomes, one might wonder if this phenomenon could have a more widespread impact on cloning in the future."[24]
The study of Calico cats may have provided significant findings relating to physiological differences between female and male mammals.[16][20][25]
Folklore
Cats with calico coloration are believed to bring good luck in the folklore of many cultures.[26] In Germany, the word for a cat with calico coloring is "Glückskatze" or "lucky cat". In the United States, calicoes sometimes are referred to as money cats.[27] In Japan, Maneki-neko figures depict calico cats, bringing good luck. Japanese sailors often kept a calico as their ship's cat to protect against misfortune at sea.[28]
Literature
In the late nineteenth century, Eugene Field published "The Duel", a poem for children also known as "The Gingham Dog and the Calico Cat".
See also
- Bicolor cat
- Brindle
- Cat coat genetics
- Deaf white cat
- Maltese cat
- Point coloration
- Tabby cat
- Tortoiseshell cat
References
- ISBN 1-85152-923-3
- ^ Bojo, Amy (9 June 2020). "How To Tell Difference Between Calico, Tortie, Torbie, Tabby Cats and Kittens". lovemeow.com.
- ^ Cat Colors FAQ: Common Colors - Torties, Patched Tabbies and Calicos :Archived 5 October 2011 at the Wayback Machine
- ^ a b c Robinson, Richard. "Mosaicism". Genetics. New York: Macmillan Reference USA, 2003. 76-80.
- ^ Trent, Courtney (16 March 2022). "Are All Calico Cats Female". Wind Haven Ocicats. Retrieved 10 April 2022.
- ^ "Calico cat". Encyclopædia Britannica. Retrieved 5 December 2014.
- PMID 6035565. Retrieved 22 June 2020.
- ^ Todd, Neil B. (November 1977) Cats and Commerce. Scientific American.
- ^ a b Hubbell, Sue. Shrinking the Cat: Genetic Engineering Before We Knew About Genes. Boston: Houghton Mifflin, 2001.
- ^ "Calico Cat, Maryland State Cat". msa.maryland.gov.
- ^ Encyclopædia Britannica (2008). "calico".
- ^ "You searched for calico, Muslin, gauze".
- ^ "Calico definition and meaning". Collins English Dictionary. Retrieved 10 February 2023.
- ^ "The Science Behind the Calico Cat's Colors". Lets talk science. 17 March 2020. Retrieved 16 March 2022.
- ISBN 978-0750635400
- ^ a b c d e Travis, John. "Silence of the Xs". Science News. 158 (6): 92–94. 5 August 2000.
- ^ Gilbert, Scott F. "Transcriptional Regulation of an Entire Chromosome: Dosage Compensation." Developmental Biology, Sunderland, Mass.: Sinauer Associates, 2000.
- ^ a b "The Genetics of Calico Cats - QPS Clinical Research". QPS. 16 December 2020. Retrieved 18 March 2022.
- ^ "Calico Cats: Guide & Facts". 22 December 2020.
- ^ a b Gunter, Chris. "She Moves in Mysterious Ways". Nature 17 March 2005.
- ^ a b "Are All Orange Cats are Male, and Calico Cats are Female?". PussMeow. Archived from the original on 30 June 2020. Retrieved 4 May 2020.
- PMID 1163864.
- ^ "What's A Chimera? Thanks To A Genetic Anomaly, An Extremely Rare Fertile Male Calico Is Born". Cat Gazette. 6 April 2018. Retrieved 24 June 2020.
- ^ Tsernoglou, Penelope Ann. "To Clone or Not to Clone: A Look at Why Cloning Fluffy and Fido Might Not Be in the Best Interests of Society and May Inevitably Pave the Way for Human Cloning." 25 April 2004. Web. 24 April 2010. <http://www.law.msu.edu>.
- ^ Pearson-White, Sonia. "Mammalian Genetics: X/imprinting Archived 17 June 2010 at the Wayback Machine". The University of Virginia. 2004. Accessed 23 May 2010.
- ^ Hartwell, Sarah (1995). "Feline Folktails - Cats in Folklore and Superstition". Retrieved 22 January 2009.
- ^ Finegan, Edward; Rickford, John (2004). "Language in the USA: Themes for the Twenty-first Century". Cambridge University Press. Archived from the original on 12 January 2013. Retrieved 22 January 2009.
- ^ Finlay, Katie (25 November 2017). "4 Things You Didn't Know About Calico Cats". iHeartCats.com. Iheartcats.com. HomeLife Media. Retrieved 17 January 2018.
External links
- Media related to Calico cats at Wikimedia Commons