OMIA:001201-9685 : Coat colour, orange in Felis catus (domestic cat)

In other species: golden hamster

Categories: Pigmentation phene

Links to MONDO diseases: No links.

Mendelian trait/disorder: yes

Mode of inheritance: X-linked

Considered a defect: no

Key variant known: no

Species-specific name: Tortoishell; tortoiseshell

Mapping: Grahn et al. (2005) localised this locus to within 14 cM of the centromere of the X chromosome. Schmidt-Küntzel et al. (2009) refined the location to a 3.5Mb region of the q arm "between markers at positions 106 and 116.8 Mb in the [then] current 1.9x-coverage sequence assembly of the cat genome".

Genetic engineering: Unknown
Have human generated variants been created, e.g. through genetic engineering and gene editing

Cite this entry

Nicholas, F. W., Tammen, I., & Sydney Informatics Hub. (2023). OMIA:001201-9685: Online Mendelian Inheritance in Animals (OMIA) [dataset].


Note: the references are listed in reverse chronological order (from the most recent year to the earliest year), and alphabetically by first author within a year.

2023 Owen, R.E. :
Half-chromatid mutation as a possible cause of mosaic males and females in hymenoptera and rare fertile male tortoiseshell cats. Genome , 2023. Pubmed reference: 37307601. DOI: 10.1139/gen-2023-0006.
2020 Bugno-Poniewierska, M., Kij, B., Witarski, W., Wojtaszek, M., Radko, A., Podbielska, A., Szczerbal, I., Murphy, W.J. :
Fertile male tortoiseshell cat with true chimerism 38,XY/38,XY. Reprod Domest Anim 55:1139-1144, 2020. Pubmed reference: 32574385. DOI: 10.1111/rda.13752.
Jaraud, A., Bossé, P., Dufaure de Citres, C., Tiret, L., Gache, V., Abitbol, M. :
Feline chimerism revealed by DNA profiling. Anim Genet 51:631-633, 2020. Pubmed reference: 32452546. DOI: 10.1111/age.12957.
2018 Szczerbal, I., Krzeminska, P., Dzimira, S., Tamminen, T.M., Saari, S., Nizanski, W., Gogulski, M., Nowacka-Woszuk, J., Switonski, M. :
Disorders of sex development in cats with different complements of sex chromosomes. Reprod Domest Anim 53:1317-1322, 2018. Pubmed reference: 30099782. DOI: 10.1111/rda.13263.
2017 De Lorenzi, L., Banco, B., Previderè, C., Bonacina, S., Romagnoli, S., Grieco, V., Parma, P. :
Testicular XX (SRY-negative) disorder of sex development in cat. Sex Dev 11:210-216, 2017. Pubmed reference: 28848109. DOI: 10.1159/000479175.
2015 Du, X.Y., Yi, S., Huo, X.Y., Wang, C., Liu, D.F., Ren, W.Z., Chen, Z.W. :
Selecting representative microsatellite loci for genetic monitoring and analyzing genetic structure of an outbred population of orange tabby cats in China. Genet Mol Res 14:1788-97, 2015. Pubmed reference: 25867323. DOI: 10.4238/2015.March.13.6.
Szczerbal, I., Stachowiak, M., Dzimira, S., Sliwa, K., Switonski, M. :
The first case of 38,XX (SRY-positive) disorder of sex development in a cat. Mol Cytogenet 8:22, 2015. Pubmed reference: 25838845. DOI: 10.1186/s13039-015-0128-5.
2014 Pedersen, A.S., Berg, L.C., Almstrup, K., Thomsen, P.D. :
A tortoiseshell male cat: chromosome analysis and histologic examination of the testis. Cytogenet Genome Res 142:107-11, 2014. Pubmed reference: 24335095. DOI: 10.1159/000356466.
2009 Schmidt-Küntzel, A., Nelson, G., David, V.A., Schäffer, A.A., Eizirik, E., Roelke, M.E., Kehler, J.S., Hannah, S.S., O'Brien, S.J., Menotti-Raymond, M. :
A domestic cat X chromosome linkage map and the sex-linked orange locus: mapping of orange, multiple origins and epistasis over nonagouti. Genetics 181:1415-25, 2009. Pubmed reference: 19189955. DOI: 10.1534/genetics.108.095240.
2007 Golubeva, N.A., Zhigachev, A.I. :
[New data on coat color gene frequencies in cats: 1. the Armavir population]. Genetika 43:1079-83, 2007. Pubmed reference: 17958308.
2005 Grahn, RA., Lemesch, BM., Millon, LV., Matise, T., Rogers, QR., Morris, JG., Fretwell, N., Bailey, SJ., Batt, RM., Lyons, LA. :
Localizing the X-linked orange colour phenotype using feline resource families. Anim Genet 36:67-70, 2005. Pubmed reference: 15670134. DOI: 10.1111/j.1365-2052.2005.01239.x.
2003 Kuiper, H., Hewicker-Trautwein, M., Distl, O. :
[Cytogenetic and histologic examination of four tortoiseshell cats] Dtsch Tierarztl Wochenschr 110:457-61, 2003. Pubmed reference: 14679839.
2001 Kosowska, B., Januszewski, A., Tokarska, M., Jach, H., Zdrojewicz, Z. :
Cytogenetic and histologic studies of tortoiseshell cats Medycyna Weterynaryjna 57:475-479, 2001.
2000 Christensen, A.C. :
Cats as an aid to teaching genetics. Genetics 155:999-1004, 2000. Pubmed reference: 10880464.
1999 Leaman, T., Rowland, R., Long, S.E. :
Male tortoiseshell cats in the United Kingdom Veterinary Record 144:9-12, 1999. Pubmed reference: 10028567.
Long, S.E. :
38,XX/38,XY chromosome chimaerism in three feline siblings. Vet Rec 145:404-5, 1999. Pubmed reference: 10574275.
1996 Axner, E., Strom, B., Linde Forsberg, C., Gustavsson, I., Lindblad, K., Wallgren, M. :
Reproductive disorders in 10 domestic male cats Journal of Small Animal Practice 37:394-401, 1996. Pubmed reference: 8872943.
1995 Pontier, D., Rioux, N., Heizmann, A. :
Evidence of selection on the orange allele in the domestic cat felis catus - the role of social structure Oikos 73:299-308, 1995.
1992 Quackenbush, R.E. :
Genetics of the Domestic Cat - A Lab Exercise American Biology Teacher 54:29-32, 1992.
1988 Chastain, C.B., Guilford, W.G., Schmidt, D. :
The 38,XX/39,XXY genotype in cats Compendium on Continuing Education for the Practicing Veterinarian 10:18-22, 1988.
1987 Robinson, R. :
Mutant gene frequencies in cats of the greater London area. Theor Appl Genet 74:579-83, 1987. Pubmed reference: 24240212. DOI: 10.1007/BF00288855.
Wagner, A., Wolsan, M. :
Pelage mutant allele frequencies in domestic cat populations of Poland. J Hered 78:197-200, 1987. Pubmed reference: 3611716.
1986 Miller, W.J., Hollander, W.F. :
The sex-linked black cat fallacy: a textbook case Journal of Heredity 77:463-464, 1986. Pubmed reference: 3559170.
1985 Robinson, R. :
Fertile male tortoise-shell cats Journal of Heredity 76:137-138, 1985.
1984 Moran, C., Gillies, C.B., Nicholas, F.W. :
Fertile male tortoiseshell cats: mosaicism due to gene instability? Journal of Heredity 75:397-402, 1984. Pubmed reference: 6481130.
1981 Hageltorn, M., Gustavsson, I. :
XXY-trisomy identified by banding techniques in a male tortoiseshell cat. J Hered 72:132-4, 1981. Pubmed reference: 7196925.
Long, S.E., Gruffydd-Jones, T., David, M. :
Male tortoiseshell cats: an examination of testicular histology and chromosome complement Research in Veterinary Science 30:274-280, 1981. Pubmed reference: 7255921.
1980 Nicholas, F.W., Muir, P., Toll, G.L. :
An XXY male Burmese cat Journal of Heredity 71:52-54, 1980.
1979 Fagan, E.A. :
The gingham dog and the calico cat. Nurs Adm Q 3:57-62, 1979. Pubmed reference: 257210.
Logue, DN. :
Tortoiseshell tom. Vet Rec 105:381-2, 1979. Pubmed reference: 532047.
1975 Centerwall, WR., Benirschke, K. :
An animal model for the XXY Klinefelter's syndrome in man: tortoiseshell and calico male cats. Am J Vet Res 36:1275-80, 1975. Pubmed reference: 1163864.
1973 Centerwall, WR., Benirschke, K. :
Male tortoiseshell and calico (T-C) cats. Animal models of sex chromosome mosaics, aneuploids, polyploids, and chimerics. J Hered 64:272-8, 1973. Pubmed reference: 4798734.
Lamoreux, ML. :
Brown-orange tortoiseshell cat. J Hered 64:240, 1973. Pubmed reference: 4766215.
1972 Robinson, R. :
Mutant gene frequencies in cats of Cyprus. Theor Appl Genet 42:293-6, 1972. Pubmed reference: 24431063. DOI: 10.1007/BF00277721.
1971 Gregson, NM., Ishmael, J. :
Diploid-triploid chimerism in 3 tortoiseshell cats. Res Vet Sci 12:275-9, 1971. Pubmed reference: 5103434.
Pyle, R.L., Patterson, D.F., Hare, W.C., Kelly, D.F., Digiulio, T. :
XXY sex chromosome constitution in a Himalayan cat with tortoise-shell points. J Hered 62:220-2, 1971. Pubmed reference: 5137354.
1970 Loughman, W.D., Frye, F.L., Condon, T.B. :
XY/XXY bone marrow mosaicism in three tricolour cats American Journal of Veterinary Research 31:307-314, 1970. Pubmed reference: 5414872.
1969 Robinson, R., Silson, M. :
Mutant gene frequencies in cats of Southern England. Theor Appl Genet 39:326-9, 1969. Pubmed reference: 24435560. DOI: 10.1007/BF00281914.
1967 Malouf, N.K., Benirschke, K., Hoefnagel, D. :
XX/XY chimerism in a tricoloured male cat Cytogenetics 6:228-241, 1967. Pubmed reference: 6035565.
1964 Chu, EH., Thuline, HC., Norby, DE. :
Triploid-diploid chimerism in a male tortoiseshell cat Cytogenetics 24:1-18, 1964. Pubmed reference: 14154339.
Thuline, H.C. :
Male tortoiseshell, chimerism and true hermaphroditism Journal of Cat Genetics 4:2-3, 1964.
1961 Thuline, H.C., Norby, D.E. :
Spontaneous occurrence of chromosome abnormality in cats Science 134:554-555, 1961. Pubmed reference: 13776765.
1957 Jude, AC., Searle, AG. :
A fertile tortoiseshell tomcat. Nature 179:1087-8, 1957. Pubmed reference: 13430803.
Little, CC :
The yellow Siamese cat Journal of Heredity 48:57-58, 1957.
1956 Ishihara, T. :
Cytological studies on tortoiseshell male cats Cytologia 21:391-398, 1956.
Sprague, L.M., Stormont, C. :
A reanalysis of the problem of the male Tortoiseshell cat Journal of Heredity 47:237-240, 1956.
1927 Bamber, R.C., Herdman, E.C. :
The inheritance of black, yellow and tortoiseshell coat colour in cats Journal of Genetics 18:87-97, 1927.
1919 Little, C.C. :
Colour inheritance in cats, with special reference to colours, black, yellow and tortoiseshell. Journal of Genetics 8:279–290, 1919. DOI: 10.1007/BF02983269.
1918 Wright, S. :
Color inheritance in mammals. X. The cat - Curious association of deafness with blue-eyed white color and femaleness with tortoise-shelled color, long known - variations of tiger pattern present in interesting features Journal of Heredity 9:139-144, 1918. DOI: 10.1093/oxfordjournals.jhered.a111923.
1916 Ibsen, H.L. :
Tricolor Inheritance. III. Tortoiseshell Cats. Genetics 1:377-86, 1916. Pubmed reference: 17245865. DOI: 10.1093/genetics/1.4.377.
1913 Domcaster, L. :
On sex-limited inheritance in cats, and its bearing on the sex-limited transmission of certain human abnormalities. Journal of Genetics 3:11-23, 1913. DOI: 10.1007/BF02981561.
1909 Bateson, W. :
Mendel’s Principles of Heredity. Cambridge University Press, London , 1909. URL:
1904 Doncaster, L. :
On the inheritance of tortoiseshell and related colours in cats Proceedings of the Cambridge Philosophical Society 13:35-38, 1904.

Edit History

  • Created by Frank Nicholas on 17 Sep 2005
  • Changed by Frank Nicholas on 07 Jun 2012
  • Changed by Imke Tammen2 on 15 Jun 2023
  • Changed by Imke Tammen2 on 19 Aug 2023