A simple way to work out what kittens your cat might have, is to build a simple chart, and work out the combinations of genes.
I’ll continue to use the short and long hair genes, as they are the simplest example to start with.
Start by drawing a chart that is 3 boxes wide and 3 boxes deep. Ignore the top left hand box. Now fill in the the top row with the stud’s genes, and in the left hand column the queen’s genes.
In the example below, both the stud (at the top) and the queen (at the side) have one short hair gene and one long hair gene. The symbol for the short haired gene is ‘L’ and the symbol for the long haired gene is ‘l’.
Notice that the dominant and recessive genes use the same letter, but the dominant gene is in upper case (L) and the recessive gene is in lower case (l).
| Male | |||
| Short Hair (L) | Long Hair (l) | ||
| Female | Short Hair (L) | ||
| Long Hair (l) | |||
Now take the symbol from the left hand male box (L), and combine it with the top one from the female (L).
| Male | |||
| Short Hair (L) | Long Hair (l) | ||
| Female | Short Hair (L) | L L | |
| Long Hair (l) | |||
Now add the symbol from the left band male box with the bottom one from the female.
| Male | |||
| Short Hair (L) | Long Hair (l) | ||
| Female | Short Hair (L) | L L | |
| Long Hair (l) | L l | ||
Now do the same for the right hand two boxes:
| Male | |||
| Short Hair (L) | Long Hair (l) | ||
| Female | Short Hair (L) | L L | I L |
| Long Hair (l) | L l | ||
| Male | |||
| Short Hair (L) | Long Hair (l) | ||
| Female | Short Hair (L) | L L | I L |
| Long Hair (l) | L l | l l | |
You should end up with:
| Male | |||
| Short Hair (L) | Long Hair (l) | ||
| Female | Short Hair (L) | L L | I L |
| Long Hair (l) | L l | l l | |
Top left, you have L L - two short haired genes (L) - this kitten will be short haired (homozygous)
Top right, and bottom left - you have one L and one l - one short haired gene and one long haired gene - these two kittens are short haired but carry long hair (the short hair gene is dominant, so the long hair gene is ‘invisible’)
Bottom right is l l - two long haired genes - so this kitten is long haired.
So the average that you would get from this mating are half the kittens being short haired, but carrying long hair (heterozygous), 25% being Long Haired (homozygous) and 25% Short Haired (homozygous).
Remember though, that these are only averages. Some eggs may die before they are fertilised, some sperm may never get that far, and then fertilised eggs may not survive. And you never know which ones will actually go full term.
So don’t expect to always get one long haired kitten in every litter of four. You have to repeat several matings before the ‘averages’ start to show up.
You can use this chart to work out the coat type, pattern or colour of any of the genes below - though the chart gets rather big and complicated if you try to chart more than one gene at a time - as you have to allow for every combination that might occur.
To work out the combinations of one gene, there are four possible combinations (the male carries a pair, and the female carries a pair). But to work out the combinations of two genes together (e.g. marbled or spotted, and snow or brown), there are sixteen possible combinations. As you might guess, the boxes get a bit big and complicated, and it is easy to lose track if you try to do too many combinations at a time.
Just as an example, here is a box where both the male and the female are brown spotted, but where they both carry marble and snow. Marble is recessive to spotting, and snow is recessive to brown.
Top right, and bottom left - you have one L and one l - one short haired gene and one long haired gene - these two kittens are short haired but carry long hair (the short hair gene is dominant, so the long hair gene is ‘invisible’)
Bottom right is l l - two long haired genes - so this kitten is long haired.
So the average that you would get from this mating are half the kittens being short haired, but carrying long hair (heterozygous), 25% being Long Haired (homozygous) and 25% Short Haired (homozygous).
Remember though, that these are only averages. Some eggs may die before they are fertilised, some sperm may never get that far, and then fertilised eggs may not survive. And you never know which ones will actually go full term.
So don’t expect to always get one long haired kitten in every litter of four. You have to repeat several matings before the ‘averages’ start to show up.
You can use this chart to work out the coat type, pattern or colour of any of the genes below - though the chart gets rather big and complicated if you try to chart more than one gene at a time - as you have to allow for every combination that might occur.
To work out the combinations of one gene, there are four possible combinations (the male carries a pair, and the female carries a pair). But to work out the combinations of two genes together (e.g. marbled or spotted, and snow or brown), there are sixteen possible combinations. As you might guess, the boxes get a bit big and complicated, and it is easy to lose track if you try to do too many combinations at a time.
Just as an example, here is a box where both the male and the female are brown spotted, but where they both carry marble and snow. Marble is recessive to spotting, and snow is recessive to brown.
| Male | |||||
| Spotted & Snow | Marble & Snow | Spotted & Brown | Marble & Brown | ||
| Female | Spotted & Snow | 2xspotted genes 2x snow genes = snow spotted |
1 spot + 1 marble 2x snow genes = snow spotted |
2xspotted genes 1 brown+1 snow = brown spotted |
1 spot + 1 marble 1 brown+1 snow = brown spotted |
| Marble & Snow | 1 spot + 1 marble 2x snow genes = snow spotted |
2x marble genes 2x snow genes = snow marble |
1 spot + 1 marble 1 brown+1 snow = brown spotted |
2x marble genes 1 brown+1 snow = brown marble |
|
| Spotted & Brown | 2xspotted genes 1 brown+1 snow = brown spotted |
1 spot + 1 marble 1 brown+1 snow = brown spotted |
2xspotted genes 2x brown genes = brown spotted |
1 spot + 1 marble 2x brown genes = brown spotted |
|
| Marble & Brown | 1 spot + 1 marble 1 brown+1 snow = brown spotted |
2x marble genes 1 brown+1 snow = brown marble |
1 spot + 1 marble 2x brown genes = brown spotted |
2x marble genes 2x brown genes = brown marbled |
|
So out of the mating of two brown spotteds who both carry marble and snow you would get (on average for 16 cats):
3 snow spotted, 2 of which carry marble
9 brown spotted - 2 carrying snow, 4 carrying snow and marble, 1 carrying marble and one homozygous
1 snow marble
3 brown marbles, 2 of which carry snow
3 snow spotted, 2 of which carry marble
9 brown spotted - 2 carrying snow, 4 carrying snow and marble, 1 carrying marble and one homozygous
1 snow marble
3 brown marbles, 2 of which carry snow
Bengal Genes
These are the main genes that affect the Bengal, with an explanation
of each of them. As said previously, research is still taking place and
new genes are being discovered all the time, so if you know more,
please let me know (contact details at the bottom of the page).
I have included some genes that do not relate directly to the Bengal, as they help clarify how other cats differ.
I have included some genes that do not relate directly to the Bengal, as they help clarify how other cats differ.
| Dominant | Recessive | Notes |
| A Agouti | a non-agouti |
Agouti is the tabby/patterned cat Non-agouti is the self coloured (solid colour) cat A is dominant to a, though not always completely - you can sometimes see the shadow of the tabby pattern on a solid coloured black cat that is heterozygous (i.e. on one that is Aa) a in combination with the Inhibitor gene (I) can cause smoke (see more at the bottom of this page) |
| B Black | b chocolate |
b is the chocolate gene - all of the black is replaced by a rich chocolate brown B is incompletely dominant to b Bb can result in a black cat with rusty coloured shading b is incompletely dominant to b1 |
| b1 cinnamon |
b1 is the cinnamon gene - where the black is replaced by a rich cinnamon brown A cat that is b1 b1 will be cinnamon, but where the cat is b b1, they are often a pale shade of chocolate, as b is not completely dominant to b1 |
|
| C Full Colour | c albino | The albino cat with no colour and pink eyes (not relevant to the Bengal) |
| ca blue-eyed white | The blue-eyed white cat (does not relate to the Bengal - this cat is white all over) | |
| cs siamese |
Ivory background, coloured points and blue eyes -the blue-eyed snow (seal lynx point) Note that reddish blue eyes may be a sign that this cat also carries chocolate |
|
| cb burmese | Ivory background, darker (sepia) coloured points, with brown, yellow or green eyes (seal sepia) | |
| If you have a Bengal that has one cs gene and one cb gene, then the two genes ‘mix’ - neither is dominant or recessive to one another. The result is the Seal Mink - with turquoise eyes. This combination of genes is referred to as the ‘Tonkinese’ colour | ||
| D Dense Colour | d dilute colour |
Dense colour is fully dominant to dilute colour. A combination of BBDD gives a black cat, but BBdd is a blue cat A brown cat (bb) with dilute (dd) is a lilac A cinnamon cat (b1b1) with dilute (dd) is a fawn A sex linked Orange cat (OO) with dilute (dd) is a cream The combination of Agouti (A) and dilute (d) causes a cream base coat rather than the usual Agouti yellow base coat. |
| Dm Dilute Modifier | dm normal dilution (maltese dilution) |
The Dm gene only takes affect where dd is also present. On blue, lilac and fawn cats with Dm = caramel Red cats with Dm = apricot |
| I Colour Inhibitor | i normal colour |
The standard description of the Inhibitor gene is that it is a
completely dominant gene which inhibits all colour in the coat - i.e.
causes silver. However, it appears to be either incompletely dominant, or is affected by rufousness - as we have all seen the ‘tarnished’ silver who has some hint of brown in the coat. A combination of Agouti (AA) with the inhibitor (I) causes smoke in some cases. Some believe that both the Inhibitor gene and the Agouti gene come in varying ‘strengths’, and that an excess of Inhibitor with insufficient Agouti causes the smoke. However, it is possible that other, as yet unidentified genes are coming into play. See below for more details on silvers |
| L Short Hair | l long hair | The short haired gene is completely dominant to the long hair gene. The sources I have read say that ‘the length of hair is determined by selective breeding’ - however this comment in itself indicates that another gene (or genes) may be present which affect hair length - and the ‘selective breeding’ is selecting cats with this other ‘hair length modifier’ gene(s). |
| Mc Vertical flow | mc circular flow | The Mc gene gives a vertical stripe or pattern, but the mc gene causes a swirling/circular pattern |
| mz horizontal flow | Currently a theory only - believed to cause the horizontal alignment of the pattern found only in Bengals and believed to be inherited directly from the ALC | |
| Mi Not glittered | mi glittered | Another ‘theoretical’ gene - causing the glitter on the Bengal coat. The designation of Mi is only ‘temporary’ - I have also seen this gene referred to as Gi or Gl. The glitter is caused by the tip of each hair shaft being hollow, so that the light passes through the hair tip. |
| Rf Normal colour | rf rufous |
Originally thought to be a series of polygenes (blending genes),
the rufous gene is now thought to be a separate gene that causes red in
the coat. There is still some work to be done here, as another theory believes that the rufous colouring is caused by the ‘extension’ gene. However, the amount of red in a Bengal coat varies considerably from cat to cat, and not in direct relationship to the width of the colour bands. My personal opinion is that this gene may come in varying ‘strengths’, or is affected by another gene that changes the amount of red in the coat. |
| S White spotting | s no white spotting |
Incomplete dominance in that Ss will have some white spotting SS = Harlequin or Van >2/3rds white Ss = Bicolour 2/3rds white So what causes the locket? Is the locket caused by another variation on this gene, that hasn’t yet been identified? Or is it just an Ss with very little white. |
| Sa Normal hair | sa satin/silk fur |
Another ‘theoretical’ gene - No or minimal undercoat, with a satin finish to the coat I has been suggested that this gene is another or different cause for glitter (see Mi), however I think most Bengal breeders will agree that this is unlikely as Bengals that have silky fur with no undercoat are not always glittered. |
| Sp Pattern Interrupt | sp normal tabby (Classic or Mackerel) |
Now identified as a separate gene affecting the tabby pattern by breaking up the pattern to cause spots rather than lines. It is still not known what causes the variance in spot shapes and colours (i.e. rosetting) |
| E Extension Gene |
Determines the width of the colour banding on a patterned (agouti) coat |
|
| O Sex linked orange | o not orange |
I have only included this one because some of the early Bengals did carry sex-linked orange (notably Millwood Pennybank). The male is an xy, and the femal is an xx, and the o gene can only ‘attach’ to the x gene, so a male can only ever carry one o gene, but a female can carry a pair. xxoo = female not red or cream xyo = male not red or cream xxOo = female tortie/tortoishell xxOO = female red (or cream with dd) xyO = male red |
Birth Defects
| Flat Chest | There are very mixed feelings as to whether this caused by a recessive gene or by environmental affects, or a mixture of both. |
| Kinked Tail |
Possibly caused by a recessive gene There is a possibility that there is a link between tail faults and spina bifida. |
| Cleft Palate | Opinion varies as to whether this is caused by a gene, by immaturity at birth, or a congenital birth defect caused by some outside influence during pregnancy. |
Smoke, Charcoal and Melanistic Bengals
I have read and heard so many things about the smoke, charcoal and
melanistic bengals, and I think there is quite a bit of confusion over
these colours.
What I would like to do here is clarify what we do know, and what we don't know, as at May 2013.
Smoke, melanism and charcoal are different colours. A melanistic cat is not a charcoal, or a smoke, any more than a blue lynx point is a seal lynx point.
What I would like to do here is clarify what we do know, and what we don't know, as at May 2013.
Smoke, melanism and charcoal are different colours. A melanistic cat is not a charcoal, or a smoke, any more than a blue lynx point is a seal lynx point.
Smoke
I think it is fairly clear in most people's minds that the Smoke bengal is a (non-agouti) Black Silver Bengal.
a/a - homozygous for non-agouti
I/i or I/I - heterozygous or homozygous for inhibitor
Most Bengals have two agouti genes (the gene that causes the pattern in the coat), but there are some that have one agouti gene and one non-agouti - so they are A/a.
If you mate two cats together that carry non-agouti (a), there is a 25% chance of getting a solid coloured cat (no pattern). And if one or both of the parents is silver, there is a chance that solid coloured cat will be a smoke (a combination of Silver and non-agouti).
They are easy to identify, as at least one parent must be silver, and if you part the hair, although it is black down most of it's length, the base of every hair is silver.
a/a - homozygous for non-agouti
I/i or I/I - heterozygous or homozygous for inhibitor
Most Bengals have two agouti genes (the gene that causes the pattern in the coat), but there are some that have one agouti gene and one non-agouti - so they are A/a.
If you mate two cats together that carry non-agouti (a), there is a 25% chance of getting a solid coloured cat (no pattern). And if one or both of the parents is silver, there is a chance that solid coloured cat will be a smoke (a combination of Silver and non-agouti).
They are easy to identify, as at least one parent must be silver, and if you part the hair, although it is black down most of it's length, the base of every hair is silver.
Charcoal
So, what causes 'charcoal'?
At this point in time (May 2013) nobody knows what causes charcoal, as they have only recently started to search for the cause of this colouration. So any statements about the 'charcoal gene' are pure speculation at this point in time.
It may be a single gene, or it may be a combination of genes, or it may just be a variation in an existing gene (such as the variation in the long hair gene that causes various lengths of long hair).
A charcoal is not a silver cat, and does not have to have a silver parent. It may or may not carry one non-agouti gene.
The cat is genetically a brown (black) bengal, but it is very dark in appearance and there is little or no rufous colouration.
So my own personal opinion is........ that the charcoal bengal is simply the other end of the 'brown scale' to a sorrel bengal. We don't hunt for a sorrel gene, we just accept that this is a brown (black) bengal, where the markings are brown, rather than black, and the coat has heavy rufous colouration.
So perhaps a charcoal bengal is a brown (black) bengal where the markings are all black, with no brown, and there is no rufous colouration.
Just my opinion, and only based on me looking at the pedigrees of the various 'charcoal' cats that I have seen. Only time (and lots of research) will give us the answer.
At this point in time (May 2013) nobody knows what causes charcoal, as they have only recently started to search for the cause of this colouration. So any statements about the 'charcoal gene' are pure speculation at this point in time.
It may be a single gene, or it may be a combination of genes, or it may just be a variation in an existing gene (such as the variation in the long hair gene that causes various lengths of long hair).
A charcoal is not a silver cat, and does not have to have a silver parent. It may or may not carry one non-agouti gene.
The cat is genetically a brown (black) bengal, but it is very dark in appearance and there is little or no rufous colouration.
So my own personal opinion is........ that the charcoal bengal is simply the other end of the 'brown scale' to a sorrel bengal. We don't hunt for a sorrel gene, we just accept that this is a brown (black) bengal, where the markings are brown, rather than black, and the coat has heavy rufous colouration.
So perhaps a charcoal bengal is a brown (black) bengal where the markings are all black, with no brown, and there is no rufous colouration.
Just my opinion, and only based on me looking at the pedigrees of the various 'charcoal' cats that I have seen. Only time (and lots of research) will give us the answer.
Melanistic
The melanistic bengal is simply a solid black cat (a non-agouti cat).
It is not silver, is not snow, and is not homozygous for any of the dilute genes.
Sometimes you can see a shadow of the pattern in the coat (often called 'black on black'), and sometimes you cannot see any pattern.
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