Persian
Cats and Kittens for Sale UK - Tremarie UK, breeder of Persian cats.
Quality bi, tri, vans, Himalayans, Colourpoints - tabby, chocolate and
self. Chocolate Persians. Chinchillas. Small cattery.
List Of Cat Governing Bodies
Abegweit Cat Club
(member of ACFA)
All Russian Cat Club Association (ARCCA)
American Association of Cat Enthusiasts (AACE)
American Cat Fanciers Association (ACFA)
Associacio Felina de Catalunya (ASFeC)
Australian Cat Federation Inc (ACF)
Austrian Cat Fanciers (KKOE)
Bavarian Cat Fanciers Association (BCFA)
Canadian Cat Association-Association Feline Canadienne (CCA/AFC)
Capital Cats Inc (member of CCCA)
Cat Association of Tasmania (member of ACF)
Cat Association of the Northern Territory (member of ACF)
Cat Authority of Victoria Inc (member of ACF)
Cat breeders Assosiation in Poland (SHKRP)
Cat Control Council of Tasmania Inc (member of CCCA)
Cat Fanciers' Association (CFA)
Cat Fanciers Federation (CFF)
Cat Fanciers of Brazil - (member of CFA)
Cat Owners' Association of Western Australia (member of CCCA)
CATZ Inc, New Zealand (member of WCF)
CFCCQ Inc (member of CCCA)
Clube do Gato do Rio de Janeiro - (member of FIFe)
Co-ordinating Cat Council of Australia Inc (CCCA)
Everycat.UK
Estonian Cat Breeding Club (ECBC - FELIX)
European Cat Fanciers (ECF)
EveryCat (Formally CA)
Fédération Féline Française (member of FIFe)
Fédération Internationale Féline (FIFe)
Federazione Felina Italian (FFI)
Federazione Italiana Associazioni Feline (member of WCF)
Feline Association of New South Wales Inc (member of ACF)
Feline Association of South Australia (member of CCCA)
Feline Control Council of Queensland Inc (member of ACF)
Feline Control Council of Victoria Inc (member of CCCA)
Feline Control Council of Western Australia (member of ACF)
Feline Federation Europe (FFE)
Félin's Club Helvétique (FCH)
Felis Britannica (member of FIFe)
Governing Council of the Cat Fancy (GCCF)
Governing Council of the Cat Fancy of South Australia (member of ACF)
Governing Council of the Cat Fancy Victoria (member of CCCA)
Klub der Katzenfreunde Österreichs (member of FIFE)
Livre Officiel des Origines Félines (LOOF)
Malaysian Cat Club (KKM)
New South Wales Cat Fanciers Association (member of CCCA)
New Zealand Cat Fancy Inc (NZCF)
Norsk Skovkattering - (member of FIFe)
Queensland Feline Association Inc (member of ACF)
Queensland Independent Cat Council Inc (member of ACF)
Royal Cat Club Swiss (RCC)
The Belgicat Club
The International Cat Association (TICA)
The National Society for Pedigree Cat Breeders and Cat Fanciers of
Hungary (FAMKAT. member of ACFA)
Traditional and Classic Cat International (TCCI)
Traditional Cat Association (TCA)
United Feline Organization (UFO)
Vintage Cat Fanciers (member of CFA)
Waratah National Cat Alliance, Australia (member of WCF)
World Cat Federation (WCF)
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Feline Genetics
The following cat
genetics information printed below with the permission of Lorraine
Shelton:
http://www.featherland.net/GENES.HTM
(of the
Featherland Cattery)
Of all the genetics
questions I get asked, no other genetic phenomenon seems to inspire
curiosity quite like our cats that have white on them. Some are totally
white (epistatic white gene), some have patches of white (the piebald
gene), some have cute little white mittens and shoes (gloving),and some
have no more than a few little hairs of white on their chests or tummies
(lockets). Strangely enough, although all of these cats may be very
different genetically, they exhibit the results of the same
physiological phenomenon.
To understand this, we have to not only know some basics of genetics,
but some concepts of embryology as well. Most of us are familiar with
the terms "dominant" and "recessive". The piebald gene, responsible for
our bicolors and vans, is dominant. The form of white spotting seen in
Birmans in also dominant, but doesn't always show up in every cat that
inherits the gene, a characteristic called "incomplete penetrance." If a
cat has white spotting, you know that at least one parent had white on
him. The same is true of the epistatic white gene. When we see a
beautiful shimmering white Persian we know that at least one of his
parents was white. The term "epistasis" refers to the fact that the
cat's "whiteness" covers up whatever color he may be underneath. For all
you know, that white Persian is genetically a shaded tortoiseshell, or a
blue lynx point, or a dilute calico.
Two white cats can produce a non-white cat. This is because in order to
be white, the cat only needs ONE white gene. All of our genes are
inherited in sets of two, one from each parent. Each gene can come in
only one or in many "flavors" that are called "alleles". The epistatic
white gene has two alleles: W (white) and w (non-white). By convention,
recessive alleles are given lower case letters, dominant alleles upper
case. If only one parent was white, then it received a white gene (W)
from one parent and a "non-white" gene (w) from the other. Since W is
dominant over w... the cat is white. Such a cat is called
"heterozygous". "Hetero" means "different", and in this case the cat
would have the genotype Ww. Either a W or a w would be passed to each of
that cat's offspring. If both of the parents were white, the cat COULD
(but not always) get a W allele from each parent. This creates what is
referred to as a "homozygous" white cat. "Homo" means "same". This cat
would have the genotype WW and ALL offspring from this cat would be
white, as every kitten would receive a W even if the other parent only
gave him a w. When a Ww cat is bred to a Ww cat, the odds are that 25%
of the kittens will be WW, 50% will be Ww, and 25% will be ww
(non-white). The WW cat will look just like a Ww cat, therefore two cats
with different genotypes (genetic make-up) share an identical phenotype
(appearance).
This is NOT the case with the piebald white spotting gene, the one that
gives the cat fancy its lovely bicolors and tricolors. In this case, the
dominant gene is extremely variable in its expression. A cat with only
one copy of the dominant allele (genotype Ss) may only have a small
amount of white or could have a large amount of white. Cats with two
copies of the dominant allele (genotype SS) frequently have very large
amounts of white and are referred to as "vans". Carried to the extreme,
a homozygous cat may be completely white! This very rarely happens
though.
The extent to which the amount of white is expressed can be controlled
by selective breeding. By breeding only the cats with a lot of white on
them you can decrease your chances of getting cats with very little
white. This is because for every "major" gene we know about, there are
many little genes ("polygenes") that can influence what our cats look
like. For instance, ear size, coat texture, and temperament are not
controlled by major genes, but can be influenced by selective breeding
and the accumulation of desired polygenes. By the way, older articles on
bicolor breeding in Persians warn against getting "too much white".
Interesting historical observation, as at the CFA Persian Breed Council
Meeting it was agreed by the majority of breeders that you can never
have TOO much white!
The opposite direction is taken by Birman breeders. They have
selectively bred their cats for many generations to influence the way
that the piebald gene is expressed. Through careful selection of
breeding stock they can produce cats with white limited only to the four
paws with a level of consistency that is quite amazing. There has been
theorized a "gloving" gene, but the hybridization of Birmans with other
cats (both intentional and accidental) demonstrates that gloving is
definitely caused by a dominant gene, not a recessive one, and pattern
can be lost very easily, reintroducing a whole spectrum of distribution
of white. This seems to indicate that variability in expression reoccurs
once the Birmans are hybridized with other cats, a result of polygenic
factors being "bred out", whereas a major gene would be conserved in
these populations. However, when Birmans were bred to a flame point
Himalayan to introduce the red factor into some lines, the gloving was
reinstated within a few generations. It can not be ruled out at this
point that "gloving" may be a unique allele of the piebald gene,
although it seems unlikely based on these observations, in my opinion.
Another example in our spectrum of white is the case of "lockets" seen
in some cats. These are genetically solid cats with no bicolored or
white cats in their background that have a small patch of white hair
somewhere on them. This does not appear to be influenced by any major
genes, although a predisposition for lockets can "run in lines".
Removing cats that throw locketed kittens from breeding programs can
lower the incidence. Using bicolored or white cats in a breeding program
will NOT cause lockets! However, keep in mind that historically if a
cattery began having solid colored cats with lockets, a white or
bicolored breeding program would "cover up" the problem.
When these lockets occur, they are almost always seen on the underside
of a cat. Spots at the groin or chest are the most common. Now picture a
bicolored cat. These cats always have white chests and tummies. You
never see a bicolor that is black on the bottom and white on top, do
you? White kittens when they are born frequently have a patch of color
on them. Where is it?? On the topmost region of the cat: between its
ears. Are you getting the picture? White on bottom, color on top.
When an egg is first fertilized, all the cells are the same. This is
followed by a process known as differentiation, where individual cells
start to take on their unique "duties" in the complete animal. In this
process, some cells start to move from the part of the embryo called the
neural crest (at the top of what will be the kitten), down over the
sides of the embryo towards the bottom. These cells will later further
differentiate into cells responsible for many functions, including the
melanocyte cells that give color to a cat's skin and fur. If these cells
contain the genotype ww and no dominant alleles of the piebald gene they
will travel all the way to the bottom of the embryo. If they contain one
or two copies of the piebald gene, they can get "lazy" and stop before
they complete the journey. If they have one or more copies of the
epistatic white gene, this journey will be interfered with as well,
stopping very shortly after it starts.
Many factors can influence this "pigment parade". Some bicolors have
perfectly symmetrical markings, some have their white "askew". Some have
one well defined unfragmented area of white, others have color that
seems to scatter across an area. This could be due to polygenes or even
possibly what is surrounding the embryo as it develops. In a study of
the effects of ultrasound on developing human babies no ill effects were
found. However, they did find that more babies were lefthanded if they
received ultrasound treatment prior to about 12 weeks. Science has a lot
to explore in the field of embryology and environmental affects on
developing cells!
Can there be bad effects from stopping the parade of pigment forming
cells prematurely? Yes, and this is what leads to deafness in some white
cats and (very rarely) in "van" bicolors as well. As I stated earlier,
these marching neural crest cells have more than one function to
perform. Another type of cell can be formed from these neural crest
cells that is essential for sound hearing. That is why deafness is most
common in blue eyed white cats and when it occurs in vans, only in those
with VERY little color.
The pigment cells are responsible for giving our cats colored eyes as
well as colored skin and fur. An eye without these cells is blue. If the
pigment cells have marched down from the neural crest far enough to give
the eyes color, chances are they have progressed far enough to provide
sound hearing as well. But remember how some bicolors are assymetrical?
The same thing can happen in whites, causing odd eyed cats or deafness
in one ear. I have seen bicolored cats with eyes that are blue on the
side towards the middle of the face and copper on the side towards the
outside of the face. Now THAT is an odd-eyed cat! As breeding programs
consistently produce bicolored and van cats with more and more white on
them, blue and odd eyes will increase in frequency in these programs.
Most breeders know that if a white kitten has a "kitten cap" that the
kitten is probably sound of hearing. The kitten cap shows us how far the
melanoblast cells have traveled. Most of these cats are copper eyed.
When I initially started researching this subject, I was under the
misunderstanding that all blue-eyed cats were homozygous and copper eyed
cats were heterozygous. This is not true. A kitten with only one white
parent can still have blue eyes and/or be deaf. The expression of the
white gene is highly variable, however, the tendency towards blue eyes
(and deafness) can run in lines. The more blue eyed cats in the
pedigree, the greater your chances of experiencing blue eyed and/or deaf
kittens. Homozygous whites tend to have blue eyes more frequently than
heterozygous cats, indicating a possible "additive" effect influencing
the migration of pigment cells.
In my opinion, kittens with blue eyes AND sound hearing can not be
selectively bred for with any degree of consistency. If you are
selectively breeding for the pigment parade to stop as early as possible
to get those lovely blue eyes you can not avoid running into deafness at
some point. Breeding two "sound hearing" blue eyed cats to one another
in an attempt to avoid deafness is a misguided approach, in my opinion.
If deafness is to be consistently avoided, copper eyed cats (either
white or, preferably, non-white) should be used.
Do not fall into the trap of believing that there is a "deaf gene" or a
"blue eyed" gene with a simple mode of inheritance. Unfortunately, this
is NOT the case. Remember those Birmans? The pigment parade CAN be
controlled, and in these cats to an amazing degree, but it would require
many, many generations and very careful control of breeding stock,
selecting only for degree of pigment progression. If you want to get an
idea of how difficult this will be to do in a white program, visit a
bicolor breeder! The fun of working with bicolors is the incredible
diversity of expression of this gene. But it also shows how difficult it
is for us to "paint" our cats with pigment just where we want it!
Most articles that discuss the breeding of whites also mention Himalayan
programs using whites. Some breeders have worked towards sound hearing
blue eyed cats by incorporating Himalayans into their white Persian
breeding programs. If a physiologically "copper eyed" white kitten is
produced, having two copies of the recessive "siamese" gene ( a form of
albinism) can magically turn his eyes blue without any regard to how far
the pigment cells have journeyed. This basically creates a "white point"
Himalayan. However, still remember that the white gene is variable in
its expression and a blue eyed deaf kitten can also be produced by the
"traditional" effects of the white gene. My suggestion to avoid deafness
such a program? Use copper eyed white cats for breeding that had large
kitten caps. Some white cats even maintain a "kitten cap" in adulthood.
These cats probably have the least likelihood of producing deaf kittens.
For completeness, I would like to say that in some Himalayan and
Siamese/Oriental lines there is an albinism gene that has travelled
through the generations from their Siamese ancestors. This is the one
case where a cat can be white without one white parent. This is a simple
recessive gene, recessive to the "normal" siamese allele, which is
actually a form of albinism itself. I have only seen one albino
Himalayan, with very pale blue eyes. Most of these have vision problems,
such as nystagmus (eye tremors). In the case of an albino, the pigment
parade is not affected at all -- the pigment cells just don't do their
job once they get to their destination!
So now that we know that there is no "blue eyed" gene and no "deafness"
gene, what about those annoying lockets? This occurs when the pigment
cells get "lazy" and stop just short of the completion of their normal
journey. This does not appear to be due to one or two major recessive or
dominant genes, but like many other traits a tendency to throw lockets
can run in lines. Multiple polygenes are probably involved. Use a cat
for breeding that had a "locketted" littermate and you'll probably run
into the problem again. Keeping good records of ALL kittens born to a
breeding program are valuable aid in controlling the incidence of such
undesireable traits as lockets.
I had stated that using bicolors or whites in a breeding program would
not cause lockets. I would like to backstep a bit on that position. If a
breeding program is selectively breeding for large amounts of white on
their bicolors, they may also be selectively breeding for factors that
can contribute to the "laziness" of the marching melanoblast cells. This
is also true of a program selectively breeding for blue eyed whites.
This is purely speculation, and I would be interested in hearing from
white breeders producing large percentages of blue eyed white kittens.
Have you been getting locketted solids? Especially from lines that throw
BEW's bred to non-white cats? This may be the root of the "old wives
tale" that using whites will improve the amount of white on a bicolor.
Using BEW's to improve the amount of white on a bicolor, however, would
be far less effective than using a bicolor cat selectively bred for a
lot of white! It is my feeling that any influence that a white cat could
have on the markings of a bicolor would be very minor at best.
Taking advantage of the polygenes influencing other programs can also
benefit someone wishing to increase the incidence of odd eyed whites in
their lines. I have heard a theory proposed that adding bicolors to a
program will increase the incidence of odd eyes. I think this is
possible... if ASSYMETRICAL bicolors are used. Bicoloreds with perfectly
even V blazes may even DECREASE the odd of getting odd eyes, in my
opinion, because these cats reinforce the trait of symmetry.
Because the mechanisms of how the white gene and the piebald gene work
are so similar, some have proposed that the piebald gene is an allele of
the white gene. If this were so, then when a white cat with a van
(homozygous bicolor) parent is bred to a solid cat, there would never be
any solid kittens produced. The white cat's genotype would be WS, the
solid parent would be ww, and all the kittens would therefore be Ww
(white) or Sw (bicolor). A ww kitten (non-white, non-bicolor) could not
be produced. It also would mean that a white cat could never be masking
van, only bicolor. Review of persian pedigrees has revealed that whites
masking van HAVE been produced. Litters have also been produced from a
white (carrying bicolor) bred to a solid (non-white) cat that contain
solids, whites AND bicolors, proving that these genes are not at the
same locus
I hope that this gives you some insight as to how our cats get white on
them. Amount and placement of white on bicolors can be selectively bred
for. Copper vs. blue eyes on a white can also be selectively bred for,
although keep in mind that deafness and blue eyes go hand in hand! The
absence of lockets can be bred for. I hope that by understanding the
mechanism behind why our white and "with white" cats look like they do,
you can make better decisions for your own breeding program.
I'd like to thank my usual references, Book of the Cat, Roy Robinson,
and Dr. Pedersen's Feline Husbandry, as well as those embryology texts
in college, long since stacked away somewhere! I'd especially like to
thank Laura Lewellen for answering my initial questions on this
phenomenon.
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