Dominance of genes

abbreviation	meaning	dominance	possible combinations	phenotype
A	Agouti	dominant	A A A a	coat colour with agouti pattern with tabby pattern
a	non agouti	recessive	a a	coat colour without agouti pattern without tabby pattern

B	Black	dominant	B B B b B bl	coat colour uniform black On Pointed cats (f.e. Colourpoints), Burmese, Siamese the colour is called seal. On Orientals these cats are called Ebony.
b	chocolate	recessive	b b b bl	coat colour chocolate brown On Orientals these cats are called Havanna.
bl	cinnamon	recessive	bl bl	coat colour cinnamon On Abyssinian, Somali the colour is called sorrel.

C	full Colour	dominant	C C C cs C cb	coat is full coloured without points - no mask
cb	Burmese points	recessive	cb cb	burmese points - coat colour seal brown (called sable) On lighter colours the points could be seen better, the points are of the same colour as the coat colour but slightly darker.
cb	Burmese points	recessive	cb cs	Tonkinese points
cs	Siamese points	recessive	cs cs	coat colour with points: mask on the face legs and tail are coloured with the same colour as the mask light body colour eye colour is intense blue
ca	blue eyed Albino	recessive		white coat with pale blue eye colour Don't mix it up with white, which is caused by gene W.
c	Albino	recessive		white coat eye colour without pigmentation (pink)

Cu	Curled ears	dominant	Cu Cu Cu cu	ears are curled Well known is the American Curle.
cu	straight ears	recessive	cu cu	ears are straight

D	Dense - non diluted	dominant	D D D d	non diluted coat colours: black chocolate cinnamon red
d	diluted	recessive	d d	diluted coat colour: black gets blue chocolate gets lilac cinnamon gets fawn red gets cream

Fd	Folded ears	dominant	Fd Fd Fd fd	ears are folded Well known is the Scottish Fold.
fd	straight ears	recessive	fd fd	straight ears

Hr	normal coat	dominant	Hr Hr Hr hr	the whole cat is coverd with coat of normal density
hr	hairless	recessive	hr hr	almost no hairs Well known is the Sphinx.

I	Inhibitor	dominant	I I I i	supresses pigmentation of the hairs, colour only partly present on the hair shaft, coat with silver white ground
i	non silver	recessive	i i	coat colour without silver

L	shorthair	dominant	L L L l	short coat
l	longhair	recessive	l l	long coat

M	Manx	dominant	M M M m	no tail or shortened tail prenatal lethal when homozygous All Manx cats are therefore heterozygous.
m	normal tail	recessive	m m	normal length of tail

O	Orange	dominant Note: The O gene is linked to the X gene - this is called sex linked. Gene O is also a mimic gene, each colour is turned to red/orange.	O O	those cats are red females
			O Y	those cats are red males
			O o	those cats are females with a tortie shell coat, the coat colour is patched with red/cream patches
o	non orange	recessive	o o	females with non orange coat colour
o	non orange	recessive	o Y	males with non orange coat colour

R	straight hairs	dominant	R R R r	straight hairs, i.e. the hair is not wavy or curled
r	Cornish Rex coat	recessive	r r	the coat is wavy or curled with the coat structure of the Cornish Rex, Cornish don't have guard hairs.

Re	straight hairs	dominant	Re Re Re re	straight hairs, i.e. the hair is not wavy or curled
re	Devon Rex hair	recessive	re re	the coat is wavy or curled with the coat structure of the Devon Rex, guard hairs

Ro	straight hairs	dominant	Ro Ro Ro ro	straight hairs, i.e. the hair is not wavy or curled
ro	Oregon Rex hair	recessive	ro ro	coat is wavy or curled When matings between Oregon Rex and Cornish Rex or Devon Rex had been made there had been some kittens with straight hairs.

S	Piebald spotting	dominant Note: This gene is said to be inherited with incomplete dominance. The normal ratio of 3:1 is turned to 2:1:1	S S	Van The cat has only colour on its tail and some patches on the head, sometimes few smaller colour patches on the body. Note: In some federations these cats are called Harlekins.
S	Piebald spotting		S s	Harlekin, Bicolour White colour can be mostly found on the belly, on the head, on the legs, the rest of the coat is coloured.
s	non bicolour	recessive	s s	coat colour is without white

Ta	Ticked tabby	dominant Note: This gene is said to be inherited with incomplete dominance. The gene is semi-dominant to mackerel and tabby blotched.	Ta Ta	absence of stripes in the coat Well known are the Abyssinian and Somali.
Ta	Ticked tabby		Ta T Ta tb	faint and fine stripes on the legs, in the face and on the tail. Well known are the Orientals ticked tabby.
T	mackerel tabby (Tigre)	dominant over blotched tabby	T T T tb	the coat shows a mackerel pattern This is the normal wild form of the tabby pattern.
tb	tabby blotched	recessive	tb tb	the coat shows a tabby blotched pattern.

W	dominant White	dominant Note: Gene W is called a mimic gene, it covers all colours and patterns.	W W W w	the whole coat is white The eye colour can be orange blue odd eyed (one eye blue, the other one orange). This gene together with blue eyes is to be said to inherit deafness. In Orientals these cats are called Foreign Whites.
w	non white	recessive	w w	the coat is coloured with no white

Wb	Wide band	dominant	Wb Wb Wb wb	This gene is said to change the normal tabby to a golden tabby, it is said to widen the agouti bands of the hair. The gene also tends to blur the tabby pattern - referred as golden shaded or golden shells. Note: The existence of this gene is not fully proved yet.
wb	non wide band	recessive	wb wb	If this combination is present the agouti bands are of normal width - referred as silver tabbies, chinchillas and silver shaded.

Wh	Wire hair	dominant	Wh Wh Wh wh	the coat is extremly crinkled, the coat texture is rough and coarse Well known is the American Wirehair.
wh	straight hairs	recessive	wh wh	the hair is straight, not crinkled with normal texture

� European Cat Fancy 1997-1999. Please respect the Copyright. Please contact us at [email protected].
Last modified on 99-01-16

Basic Genetics: Dominance of genes

A

a

B

b

bl

C

cb

cs

ca

c

Cu

cu

D

d

Fd

fd

Hr

hr

I

i

L

l

M

m

O

o

R

r

Re

re

Ro

ro

S

s

Ta

T

tb

W

w

Wb

wb

Wh

wh