The Tabby Cat Club

 

Basic Genetics of the Tabby

The  Ticked  Tabby [T^a]

The gene responsible for the Ticked Tabby pattern is the same as that producing the pattern in the Abyssinian cat, and it is generally from that breed the gene was introduced. It was unknown in the feral population in Europe, though is relatively common in many Asian countries.

The entire body coat consists of ticked or agouti hairs, and the tabby barring appears only on the head, legs, and tail. The body fur itself is true agouti, consisting solely of evenly banded hairs. The ideal cat would have two or three bands of both the ground colour and the pattern colour, but in reality, this seldom happens and in most breeds, the evenness of ticking is deemed more important.

The Ticked Tabby is a peculiar variety in that it has two forms depending on the genotype. Because the Ticked gene [Ta] is incompletely dominant to the other alleles in the series the heterozygous form [Ta_] shows a greater degree of head, leg and tail markings than the homozygous form [Ta Ta] which has a remarkable absence of barring on the limbs, both having an evenly ticked body.  In the homozygous form [Ta Ta] Ticked Tabbies will have a dark tip to the tail, dark fur to the backs of the feet, tabby markings to the face and maybe a darker ‘skullcap’ and possibly a partial necklet, all other parts of the body will be covered by agouti hairs. Both the homozygote and the heterozygote will develop a darker dorsal are along the spine and may run along the tail to the solid tip.

Abyssinian & Somali breeders have, over very many years, selected for the homozygous form and animals showing any barring are severely penalised. The only vestiges of 'tabby pattern' which remain in the Abyssinian & Somali are a solid tail tip, dark fur to the back of the feet, and 'eye liner'. An incomplete or broken necklet is also accepted. 

In the heterozygote [Ta_] the tail markings are not complete rings as in the other Tabby patterns, but tend to be on the upper surface of the tail, though like all tabbies the tail tip is of solid colour. Breed Standards generally recognise the character of the Ticked gene, and accept that a fully ringed tail is not a realistic requirement in the Ticked Tabby, and also accept that the necklaces, of which there must be at least one, may be broken, in other words not completely joined on the chest. The tummy of the Ticked Tabby will show clear and distinct spots. The facial markings should be clear and distinct, in addition there will be a scarab or more likely a skullcap on the top of the head.

At birth a good Ticked Tabby is almost solid in colour with only minimal markings visible on the face to indicate that they are not Selfs but Tabbies! As the kittens develop the ticking begins to show through and by about three months old the kittens are miniature Ticked Tabbies with ticking showing all over the body. As the kittens grow to adulthood the ticking becomes more distinct showing greater contrast to the tail, leg and facial markings. There should be NO ghost tabby markings on the body

Some breeders produce kittens which they believe are Ticked Tabbies, these kitens are born as patterned or spotted kittens, and the markings fade as the kittens grow with agouti hairs predominating. In the majority of cases the body markings do not totally disappear even in adulthood but are visible as ghost markings. These 'pseudo-ticked' are in reality most likely to be 'standard shaded' and are not Ticked Tabbies. No Ticked Tabby should ever show any ghost markings to the body.

 

The Spotted Tabby [T]

The Spotted Tabby in its very best form is a cat of outstanding beauty. The pattern should consist of spots of solid colour on an agouti background. The spots may vary in size and should not be linked or joined or resemble broken bars.  In different breeds, the Breed Standard will describe the desired shape of the spots which may be round, oval, lozenge, arrow-shaped or some other description – these are achieved through selective breeding. 

In the Spotted Tabby the spine line must be broken into spots and a solid spine line in an adult is severely penalised. In many ‘Spotties’ three lines of spots are seen along the spine. The majority of Spotted Tabbies have barred legs, but some may have spotted legs, either of course is acceptable. The leg markings should extend as far down to the feet as possible and it is especially pleasing to see some with spots on the toes! The tail must have a solid coloured tip, and should have solid coloured rings along its entire length.  The face will have distinct tabby markings which run up to a ‘scarab’ on the top of the head.

The pattern of a Spotted Tabby should be in sharp contrast to the ground colour and the spots should be sound to the roots, showing neither lighter roots nor ticked hairs. In many Spotted Tabbies there is an excessive and unacceptable degree of ticking in the pattern area, and this obviously reduces the contrast with the ground colour (which is of course IS ticked). The pattern should be immediately visible. If you have to look for the spots on the body then the pattern is incorrect. All parts of the pattern should match in colour, the spots on the body should be the same colour as the tip of the tail. Unfortunately many breeders and judges are prepared to accept less than the best … 

 

The Mackerel Tabby [T]

In Europe feral and domestic cats of Mackerel pattern certainly exist, but they generally have white feet and bibs as well! There is considerable speculation about whether the Mackerel Tabby and the Spotted Tabby are only different expressions of the same pattern. In other words is the Spotted Tabby a Mackerel with broken bars and/or a Mackerel Tabby a Spotted with narrow linked spots? We have all seen the indeterminate cat jokingly called the "Spackerel"!  Many breeders and judges believe that a cat with broad linked spots is a Mackerel, however this is far from correct; in the Mackerel the bars are narrow unlike linked-spots.

Breed Standards for the Mackerel Tabby generally ask for narrow unbroken lines running vertically down the body from an unbroken spine line; whilst most Standards include the  Mackerel Tabby, examples are seldom seen.

The finest example of the Mackerel Tabby is seen in the Toyger, bred to resemble a small Tiger.

 

The Classic Tabby [t^b]

The Classic Pattern gene [t^b] has existed in the domestic cat since the earliest of times. It was this pattern that cat breeders first accepted as being 'Tabby'. Unfortunately because of this, there are some unenlightened people who regard them as nothing more than ordinary domestic moggies! 

The Classic Tabby is sometimes known as the 'Marbled Tabby' or the 'Blotched Tabby' and is the lowest in order of dominance, it is recessive to all other Tabby patterns; a Classic Tabby is homozygous for the pattern [t^bt^b]. When mated together two Classic Tabbies will only produce Classic pattern, and any Self-coloured kittens will be non-agouti Classics, generally showing very heavy ghost markings as kittens. Almost all the Havanas of my breeding have been of Classic pattern. Any kitten with a Classic pattern parent will carry the Classic pattern, and mated together two such cats will produce 25% kittens with Classic Pattern – though some may be non-agouti.

The Classic Pattern is possibly the most variable of the Tabby patterns, and is also visually the "heaviest" of the patterns. The pattern consists of wide stripes and whorls covering more than 50% of the body and so there is less agouti hair (ground colour) than in any other pattern.

The markings of the Classic Tabby are very distinctive and because of this various parts have been named. On the shoulders 'the butterfly' is a series of markings which should be shaped like a butterfly, though on breeds with slender shoulders this may never be as well defined as in a broader cat such as the British Shorthair or a Persian. The spine line which runs from the butterfly to the tail is broad and must be solid and unbroken; to either side and parallel with the spine line is another solid line which drops down onto the flanks.  Here there must be a large solid 'blotch' or 'oyster' which is surrounded by solid broad unbroken rings or ‘whorls’. The area between these markings is of ticked hairs, the pattern however must show no ticked or agouti hairs. It is very difficult to breed Classics which have totally symmetrical with both sides of equal merit but this must be the aim.

The pattern of the Classic Tabby is extremely variable, and though many Classic kittens may be produced it is only with selective breeding that kittens of consistent pattern form will be produced.

 

CONCERNING ALL PATTERNS

There are many features which are common to all Tabby varieties regardless of the pattern and it is therefore appropriate to deal with these in an extra-varietal manner.  Before looking at these it is important to stress the importance of understanding the difference between the pattern and the ground colour.

Firstly, the pattern (or markings) is/are the solid coloured area of the coat, in other words the spots, bars, stripes & whorls (according to variety). The pattern must be solid in colour and sound to the roots, and must show as little invasion of agouti hairs as possible. In other words the pattern should not show any ticked or banded hairs, and neither should it show light roots.

Secondly, the ground colour is the area of the coat which is made up of agouti hairs, that is the hairs which are ticked or banded.

It is essential that there is a sharp contrast between the pattern and the ground colour, and this can only be achieved when the pattern is solid in colour and free from ticking. The body markings must be as deep and free from ticking as possible and must be the same intensity and depth of colour as the facial and leg markings and the tail tip. If there is ticking in the pattern then there will be visual blurring, the contrast will be diminished and the pattern will have reduced clarity of definition - in short it will become smudged. 

The colour in Tabbies is a major part of their beauty. If the colours are poor then the whole effect, no matter how well defined or well-formed the pattern may be, will be spoiled. The Breed Standards will describe the colouring required.  The Brown Tabby generally is described as having dense BLACK markings on a warm toned coppery brown ground of agouti hairs which gives the overall impression that the cat is ‘brown’.  Without this richness of colour the ground colour will be grey giving the overall impression of a dull colour far removed from “brown”.    The same criteria will apply to all colours and the correctness of rich ground colour cannot be over-stressed.

Throat & Lip colour
One of the quirks of the Tabby patterns is the tendency to show reduced pigmentation on the chin and lips, sometimes being so pale as to appear white. Whilst Tabbies have a predisposition to pale chins it is essential that breeders positively select for colouring, and select against those animals showing white on throat and muzzle. Unfortunately, the effect of the Ticked Tabby gene [Ta] does result in a paler chin and both breeders and judges should show a greater tolerance in this particular variety.

Leg Markings
In all Tabby patterns the leg markings should ideally extend well down the leg and onto the toes. It is worth remembering that these will be better defined in the Classic Tabby than in the Spotted and the Ticked; the Breed Standards generally reflect this.

Tail Markings
Tail markings are also required in all Tabby varieties, and it is interesting to note how the tail rings differ in each variety. One common factor is that in all Patterns there must be a solid coloured tail tip. In the Classic the tail has wide rather irregular tail rings along the full length of the tail. The rings should join on the underside of the tail. The Spotted again has a ringed tail, though the rings are far more even in width and spacing, again they must join on the underside of the tail. The Mackerel (at least in the Feral cat) has very many narrow rings evenly spaced along the tail, and of course they are joined. The Ticked Tabby differs from the other patterns in that tail rings never completely encircle the tail; to find a Ticked Tabby with a fully ringed tail along its entire length AND NO body markings would be something of a miracle!  In Red and Cream tabbies the majority of cats, due to a quirk of the red gene, do not have a solid tip equivalent to that in other colours and the majority have lighter coloured tail tips

THE SILVER TABBY

Silver colouring is caused by the action of a dominant gene, called the Melanin Inhibitor [I], which prevents the full development of pigmentation in the hair. Contrary to the view held by some 'Silver' is dominant and cannot be carried by either stud or queen. To produce Silver, or Smoke, kittens one of the parents must be either Silver or Smoke. Unfortunately, the effect of the Melanin Inhibitor is variable and some Smokes may show so little expression of the gene that they appear to be self, these have been referred to as 'smoke overlaps'.

In the non-agouti cat the gene produces the white undercoat of the Smoke, this is markedly different to the 'unsound' coat. In the agouti cat the gene is more selective and a greater effect is seen on the agouti hairs than in the pattern. The pattern in effect becomes light at the roots as in the Smoke, while in the agouti hairs some of the lower coloured bands may be removed, the colour of the lighter bands is reduced significantly. This produces a very light whitish ground colour, where the agouti banding is noticeably less than in the non-silver cat, and the hairs consist of a smaller number of coloured bands with almost white in between.

The Silver versions of the Tabbies are most attractive cats, these are seen at their finest in the Silver Spotted and Silver Tabby British Shorthairs where many generations of selective breeding have taken place. There are some differences which must be remembered when looking at the coats of Silvers. Whilst the pattern must conform to the description of the Standard colours, it must be remembered that the pattern will not be sound to the roots, there will be a definite whitish section towards the skin. The Silvers also lack the warmth of colour of the standard colours, as the Melanin Inhibitor reduces the amount of pigmentation in both pattern and ground colour.

The ground colour in the Silver shows a very noticeable difference to the standard Tabby of equivalent colour. The ground colour is near-white, or white with limited coloured ticking. The less ticking the lighter the ground colour and the greater the contrast. Those cats which show a greater degree of ticking (or banding) show more colour in the ground and do not have the desired contrast. These latter coats are sometimes described as being 'muddy' or 'cloudy'.

One common failing in Silvers is that they frequently show yellowing especially to the face and legs. This is often referred to as 'tarnishing' or being 'brassy', and clearly detracts from the bright sparkling effect one is looking for in a Silver. This 'tarnishing' is caused by polygenes which enhance the richness of colour in standard varieties and is usually referred to as 'rufism'. In Silvers rufism is selected against, and so again there will be a reduction in the 'warmth' of the pattern colour. An offshoot of this is that standard coloured cats bred from Silvers frequently also lack warmth and richness of colour.

As already mentioned all Tabbies are prone to a lightening of colour on the lips, chin and throat. In Silvers the reduced pigmentation produces very light coloured, or white, chins, throats and muzzles - this is inevitable and should penalised.

 

The Wide-Band Gene - Shaded, Tipped, Golden

Though not visually showing a TABBY pattern these varieties are in fact modified Tabbies bred to show minimal tabby markings - the reverse of what the Tabby breeder wants!

The gene tentatively recognised as 'Wide-band' and designated W^b is the gene which turns the Silver Tabby into the Shaded Silver, Tipped, or Chinchilla and the standard or non-silver Tabby into the Golden or Shaded. Whilst these cats are agouti cats with a modified tabby pattern they are not regarded as being Tabby Cats. 

The basic effect of the ‘wide-band’ gene is that it greatly increases the width of bands of ticking on the hairs and effectively breaks up and distorts the pattern. Needless to say in the Silver Shaded and Tipped this is highly desirable and results in the desired cat. In the Chinchilla this has been taken to its limit and present day Chinchillas appear to be almost totally white coated. In Goldens we see a similar effect with a mantle or haze of dark tipping over a very warm ground colour.

For many years the Chinchilla was regarded almost as an independent variety, and it was some years before it was generally recognised that there was a standard or non-silver version of the Chinchilla - of course today we all recognise the 'Golden' especially in Persians and British Shorthairs. 

The Standard Shaded can look remarkably like a very poor Tabby cat, but one which appears to have more ground colour than the normal form. Though the tabby pattern may well be totally recognizable it will be rather less distinct than desired in a Tabby, and it will not be sound to the roots - it will only extend into the upper portion of the hair. Unfortunately on close examination these cats are rather reminiscent of a Ticked Tabby with very heavy ghost markings! They are however distinguishable from the Tabbies and breeders should look closely at their tabby lines. If the above seems to fit then perhaps they should investigate the possibility that they have the elusive or insidious (depending on ones viewpoint!) 'Wide-band' gene in their cats.

It is of course vitally important that breeders, exhibitors and judges do not romp away with the view that all tabbies with poor pattern definition, agouti invasion of the pattern, and unsound pattern are Shaded. Many tabbies of course do have straightforward, common-or-garden pattern faults! If however certain breeding lines consistently produce hazy pattern, and the pedigree permits, then the possibility of the presence of 'Wide-band' cannot be ignored.

It seems apparent from breeding results to date that the gene is incompletely dominant, and accordingly there is a vast difference between the homozygous cat [W^bW^b] and the heterozygote [W^bw^b]. The perfected Shaded is the homozygote and it will show minimal or preferably NO tabby markings to any part of the body excepting vestigial remains on perhaps the face. Such perfection cannot be achieved overnight and of course the early specimens, the heterozygotes, will show very poor quality tabby patterning which will be of a totally recognizable tabby pattern.

Unfortunately unless breeders and judges are rigorous in their examination of cats then they may well assume that the cats in question are conventional tabbies. Clearly this is happening with great regularity and a fairly high percentage of Silver Tabbies seen on the show bench are in fact Silver Shaded. This is also equally true in the non-silver tabbies, and there are certainly more than one or two Tabbies around which are in reality Standard Shaded of the undeveloped form.

The highly developed or perfected form of Shaded and Tipped non-silver colours, will only result from selectively breeding together cats in possession of 'wide-band'. It is seemingly the case that the true Shaded and Tipped will be of genotype W^bW^b and it is the intermediate stage W^bw^b which is causing confusion. Some lines of cats are most certainly in possession of this fascinating gene.

Of course the gene is not exclusive to agouti cats, and the Selfs may well inherit the gene. It may well be responsible for many unsound coats. In consequence Tabby breeders should pay very close regard to the soundness of coat of self-coloured studs they may consider using  on their Tabby females.

 

 

 

© John S Harrison   
2023