conversations with ISA
Nov 24 '08
The following is a email string that is posted with permission. It provides some insites to Burmilla breeding in Australia.

My name is Isabella and I am a young Burmilla breeder from Sydney Australia. I have been reading your genetic pages over and over again now for several years and I would like to thank you for putting up your findings. I am very interested in the genetics of my cats and would love to learn more. Unfortunately many of my fellow breeders are not so interested so I find myself struggling on this subject alone so I hope to find someone more knowledgeable to bounce off ideas.  I hope you can spare me some time??
I noticed that you have had an email from one of our Australian Longhair Burmilla breeders (Colleen Walters) from years ago regarding our Australian Burmilla Program.  Our program has moved on since then and our cats are now much sleeker and have moved away from the heavy chinchilla look.
I am wondering whether you can help me get my head around Burmilla colours. I recently acquired a chocolate queen (b/b brown in your classification).  I mated this girl with a stud that carries dilute and ended up with a Blue cat (cb/cb, d/d, B/b).  In Australia CFA we only have Silver and the following colours in tipped and shaded patterns:
Black (C/-, B/-, D/-)
Brown (sepia for you cb/cb, B/-. D/-)
Blue (this can be C/- or cb/cb base + B/-, d/d) – ie this covers both indigo and blue in your classification
Chocolate (brown for you – b/b. this can also be either C/- or cb/cb) – ie this can cover both brown and champagne
Lilac (b/b, d/d and this also can either be C/- or cb/cb) – ie this covers both lilac and fawn
As you can see things can be very confusing here in Aust as a C/C based Blue, chocolate or lilac cat is very different to a cb/cb based blue, choc or lilac cat as noted on your website and yet C/C and cb/cb based cats have the same classification here in Aust.  ie the differences between Indigo and Blue, brown and champagne, lilac and fawn are not noted.
We have some judges here in Aust that like to refer to cats as “bad blues” or “bad lilacs”. I suspect this is because they do not realize the difference between C/C and cb/cb colour differences. One judge even went as far as outclassing all the blue exhibits and insisted they were all caramels (ie upholding the existence of the Dm gene) because they look slightly brownish. This is way before my time but I suspect these were probably cb/cb d/d cats and this judge probably saw C/C d/d as true “blue” in her mind thus dismissing all the cb/cb d/d and called them caramel instead.
Anyway, I am going to a show this weekend and this judge will be judging my cb/cb d/d exhibit. I am totally expecting her to outclass him and call him a caramel. I have this cat DNA tested and I have my theory so I am just hoping that you can tell me if my theory is correct or at least logical. In my mind a  C/C or C/- based cat is totally different to a cb/cb based cat. I am thinking that a C/C based cat should produce a “cooler” colour eg the indigos, which is a much darker and blacker cat than say the “blue” cat which is “warmer” in appearance as it is cb/cb sepia based. I keep telling myself that if this cat is not d/d it would have been sepia hence it is logical that it has a brown tinge to him.
So the fact that all cb/cb based cats looks “warmer” / “browner” is no accident as these cats are sepia based!!!  So my theory is that that has nothing to do with the dilute modifier Dm gene.   The warm and cool tones are simply from the full expression and Burmese colours themselves.
What do you reckon about this theory? I think it should be consistent with your findings right?
Also do you know much about the Dm gene? I have done a little research on it and so far only one of the labs in California is asking for sample submissions.  This indicates to me that they are still in the testing stage and hence the Dm gene is not really proven.  Is this your understanding also?
Thank God for DNA testing.  All my breeding cats have now been DNA mapped so I know exactly what colours they carry.  I am sure you have tried the Catgene tests? Arent they brilliant?
Thank you for your time and I look forward to hearing from you soon.
Warmest regards
Isabella Wong Leung

Hi Isabella

I think you are on the right track IF  I understand you correctly.
Nice to know you folks have moved away from the Chinchilla look. It is our feeling that the breeding back to the Burmese is most necessary and the Chinchilla is only in the line once - -but that is just our view.
The lack of understanding of the subtle differences between a full expression dilute <C/-, dd> and a sepia dilute <cbcb, dd>, can be very difficult to get across to Judges who are not very familiar with the program. This gets more difficult when the cat is b/b for example:
as in
<bb, C/-, dd> versus <bb, cbcb, dd> this being  ?? Or lilac as in Burmese lilac/platinum -          -the ?? I would understand you to call< bb, C/-, dd> fawn??

To date we in Canada have been able to make some headway by conducting Judges seminars so we do have recognition of <B/-,C/-,dd>  "indigo" vs <B/-,cbcb-,dd> "blue'   and of course the <B/- C/- D/- > the black/bombay/ ebony vs <B/- cbcb, D/->  sable.
All others we need to work on and have no recognition/differentiation  in the standard on the Full expression brown  <bb C/- D/-.> versus <bb cbcb, D/-> (brown vs Champagne)  - as well as others.

However as you have pointed out the real  problem exists in identifying the Full expression brown  <bb C/- D/-> from the Sable <B/- cbcb, D/->.

Of course all this understanding gets much more difficult when the colours are disrupted to the eye  by red genetics, (tortie), and the silver /golden and tipping genes.

With regard to your comments on Caramel and Fawn there seems to be some ambiguity within the various cat fancies as to what exactly that is but I take as my reference the comments on page 114 of Robinson's 4th edition. (errors and all) using Caramel and Taupe and Apricot.
Please note I do not recognise the B1 gene as being in the gene pool and the source of Cinnamon and Fawn  see comments on my "genetics 1" page "genetics of B1".

We do not belief Pat Turner was correct in her assumption; and as noted on our genetics page1  - - and feel we have ample proof.
It is our view that the true genetics at "play" here is the golden vs silver < ii vs I/-> that although considered to be epistatic is in fact NOT,  and this <I> "silver" genetics is applying a very subtle colour variation to the solid/self cats. One has simply to look at an   agouti tipped golden Lilac cat  <A-,bb,cbcb,dd,ii> to realise this. There are numerous other examples I could suggest.

To be clear, if one looks at the genotypes as listed on p 141Robinsons  and substitutes I/- for DM/- in each case this works. What is interesting is that if one then takes that understanding and looks carefully this I/- vs ii can be seen in some non dilute <D/-> cats as well ( Robinson's suggest this can only be seen in dilute cats and that the lighter version of  blue is caramel, lilac becomes taupe and cream becomes apricot) most particularly the Champagne Burmese  ie <aa, bb, cbcb, D/-  I/- or ii > and is in fact mistakenly called the Barrington gene. (Have i spelled this correctly?)

So I would suggest that the colours are the colours,  the variation is due to the temperature sensitivity in the case of the cbcb, and the shape and clustering  of the colour dots as in bb brown and dd dilute/maltesed, and that the "warmth" or "coolness" of colour is due to the underlying I or ii, in the solid colour (a/a) cats.
Clearly you should understand that there is no great agreement with what I have just said from the folks in England or America.   BUT
I have the proof as I see it ;-))  - - see genetics I page   "More on what is a smoke" where I document the breeding of a black boy to a golden tick girl and get silver kittens. We have had previous occurrences  and numerous hints but this one we documented carefully.

End product:  I  agree with you in a qualified sense.

With regard to DNA testing, your comments are most interesting. You are ahead of me on that. I wrote to the CFA lab in Texas and the Berkley lab in California and neither answered. Certainly their tests could prove or disprove the thesis I have proposed above.  I understand there is a good DNA locus marker for ii golden vs I/- silver.
Could you advise of your contact-- and any outcomes you get.

I hope this helps.
best regards

Hey Ivan
Thanks for emailing back. I am very interested in your results. I must confess that here in Australia we do not have tabby or goldens (at least in Australia CFA anyway) so my breeding is less problematic somewhat as I am only really dealing with I/I  most of the time.  However, I have noticed that goldens do exist in the breeding program but that is due to the fact that some chinchilla breeders used Golden stock so the goldens do exist in the pedigree is mainly as very very far away ancestors to our current Burmilla cats. But as you know these recessive genes can be hidden for many years so some of our cat may be I/i you never know.
Attached linked is a DNA report from the lab (a pdf file) that I use who is affiliated with the US CFA I think. Their website is They were very slow in processing my 3 cats and then later told me that it was because these were the first Burmillas they have tested and hence they needed time to study the breed. Of course I provided as much info as possible and also included your website link re DNA study. As you can see the report is quite extensive. It gives you info re all the gene pairings and then test results on the diseases and then colour.  Note that for this one test $39US you can get PKD and a whole heap of tests done at the same time.  I advertise on my site that all my breeding stock is DNA tested PKD negative so this is a great tool for me. Re colours – they only do tests on the A/-, B/- C/- (includes all the cb points) , D/- and interestingly longhair markers but they determine this via 3 different tests.  They do not test I/- which is a shame and they also told me that they do not have tests for Dm which we don’t think exists anyway. I know there is another lab in texas collecting data for Dm but they didn’t write back to me so I suppose that project has gone to the back burner???
ed comment  in red - - -  for genetics  see also and
the catgenes web site is the site for Loraine Shelton , one of the authors of Robinsen's 4th edition
the codes on the report, here is the link to decipher it . 

By the way do you have more pictures of chocolate cats (b/b)? I just acquired a new little girl who is C/C b/b.  Her colour is not as crisp as my cb/cb b/b girl but she is tipped so you can’t see much colour on her anyway.  Just interested to see your b/b cats so I can see the visual difference between cb/cb b/b and C/- b/b.  Many thanks in advance.  I am also attaching a photo of Holly the new chocolate kitten (C/C b/b DNA tested) and Columbine my adult chocolate (cb/cb (I think only not tested) b/b).
Re the other info you gave me, I will need to sit down and boil over it some more.  It is brilliant to speak to you, I feel so happy to be talking to someone else who is interested in this sort of stuff. Most people in Aust just think that I am a bit “too keen”.
PS please feel free to post the emails. I hope they can help someone else.
Isabella Wong Leung

image 1image 2image 3
Holly?? and Holly
isa192 edit 2isa 176edit2

Hi again Isabella
I have posted your reply on the web site along with a couple of editorial inserts (links etc.) typed in red. In attaching the photo's of the cats I hope I done so correctly ??

I am surprised that the AUZ folks have been able to be so exclusively Silver < I/- > in their Burmillas -  given that the genetic understanding that Burmese are all golden  (although I would dispute that they all are). I guess there was not a lot of breeding back to the Burmese -  something we place a very high priority upon.

As you may have noticed our foundation Chinchilla Christian , who was imported from England, had a golden dame. The foundation Breeding using the North American Chinchilla also produced "goldens",  Oprah was one of them. Holding onto the "silver's" has been difficult  ;   the reason one of our breeders had to restart, and why we imported Findus.  We now take great care to hold the silver.

Additionally I am most impressed with how tipped your cats are. If our understanding is correct, that characteristic is also recessive and very easily lost  - again why we have Findus. See our discussions of what we call Swb versus  swb in Genetics of the shaded American Shorthair.   We think a tipped cat is a combination of Wb/- and swb/swb. We have only bred a few such cats,  and early on did not realise the precariousness of the situation.

Re: your question about <C/C b/b> cats they are very hard to distinguish from <cbcb B/-> cats.  Soliloquay was such a cat and was 2 years old and producing kittens before we were absolutely sure she was <bb C/->. ( link may not work ). There are two way to check other that breed verification.   - If the cat is solid colour <a/a> and not smoked,   the lack of change in colour on the ears is good ie is not pointed. The other means of telling is by looking at the paw pad colour.  It helps a lot if you have a Burmese to compare side by side.
Of course if the cat is tipped the only means of determination is by the paws.  In fact we have seen a cat Odysseus so tipped that we thought he was Champagne for about 2 years and only when his adult colour come in where we able to see the real colour along the ridge of the tail.

Your Columbine is one great looking cat. The folks in Ontario are not partial to longhaired cats, difficult for us to sell, but they do very well in Quebec. So far the Judges have not shown much favour towards the tipped cats, shaded ones do a little better. I have no idea how one would determine the colour of Holly. If you ever breed her to a Burmese I sure would like to see the outcome. We favour the Morvanka (from AUZ) Burmese as you may have realised.  What are your plans for her?? I dare not show her photo to  Miss Ann.

Re DNA report  - -would your results sheet have come with an explanation?  difficult to read without one??

best regards

     Hi Ivan
 Lovely to hear back from you again. I think you got it right, the fact that we can retain the silver so well is probably because we don’t go back to the Burmese in F4. In fact in Aust. we don’t look at the Eu program at all.  Any cat that is Chin x burmese will be foundation Burmilla SH gen 1 (with restrictions of course ie no pointed genes allowed, silver only etc, but any colour burmese is ok I think).  But in saying that we in the NSWCFA are no longer allowed to do foundation matings or backcrossing to the chin or burmese anymore  unless we ask for permission. 

So at this stage a lot of us in Sydney anyway are just doing LHB x LHB matings and most of these LHBs have Australian Tiffanies (75% chinchilla – eg burmese x chin then x chin again) in the background. But what we do now is being really selective and only choose cats that are sleek in the coat to further the program, ie we do no  choose the very fluffy ones and these are usually crucified to the nth degree on the show bench anyway.  I was the first to get the gen 3 in Syd but most people have also got there now and we are starting to see the good results from choosing the sleek coat kittens. Recently my good friend Lyn brought back a few natually occurring LHBs (eg naturally occuring LHBs from gen 2 chin x burmese matings no Aust Tiff in backgound) back from Perth.  Her friend unfortunately  died from cancer and so Lyn decided to take these cats on. One of the  cat she brought back is a gen 2 black shaded male and it seems that  he is producing really good type kittens for us. Holly is his  daughter and I have used him for 2 matings and I have several great show quality kittens from him. My Columbine is a naturally occurring  LHB from 2 SH parents. She is from Melb (Melborne) and hold some lines that we  don’t have here in Sydney.  Judges don’t like her much here in Aust as she is regarded as a little too pointy in the face.  Also her coat  is very light and the judges here prefers a slightly more filled out  cat. Usually they look for a nice domed head and nice largish ear  set. They also prefer a good distance between the ears.  We are also  getting extremely good green eye colour at the moment so that is a  very good thing for us too.

By the way, have you looked into eye colour genetics.  Several years  ago I did some studies and found that blue green eye coloured cats  are great to keep as breeders even though their eye colour may not be  100% correct as these cats can produce more green eyed colour  offsprings when mated to another green eyed cat or yellow green eyed  cat. My Columbine has beautiful aqua green eyes so I am expecting he  offsprings to have great eye colour.  Her son Blu Kaleidscope is 6 months old now and is already displaying great eye colour. Attached  is his photo he is a very nice cat  

Re tipping, this is really important to us. Most of the cats that we produce now, gen 2 and above, are very very nicely shaded/tipped.  The colour is so even you wont believe it and this is happening  across a number of catteries. I think this has something to do with the fact that we didn’t go back to burmese and perhaps the Aust Tiff  stock did help… I didn’t personally do any foundation matings but my  friend Tina did and she said that she had so many variants and very  barred cats at the start of the program and they were very hard to sell. I guess that is probably the reason why they went back to the  chinchilla to consolidate the I gene to get less variants.  Re the codes on the report, here is the link to decipher it . 

Re Holly, yes it was almost impossible for us to tell what colour she  was at the beginning. We waited till week 10 and Lyn was still not  sure.  She only really started to display colour at week 10 but I was  quite adamant when I saw her that she could be chocolate by her paw  pads and eyeliner and that dirty pink nose was a dead give away too.  Lucikly Columbine was at Lyn’s for a mating at the time and I could pull out Columbine and had a good look at her paw pads etc with  Holly’s side by side which helped. But because she had so little   colour on her coat at the time I wasnt 100% sure whether she is cb/cb   b/b or C/- b/b but I had a sneaking suspicion that she is C/- as that  chocolate colour was quite deep unlike Columbine’s crisp brown. We  decided to DNA test her in the end and she came back C/C b/b so I was  right J Lyn was happy with that as she knew that I only wanted to buy   a chocolate and not a brown so the DNA test really gave us  confidence.  But personally I really prefer the colour expression of  cb/cb b/b as it is just so bright and crisp.  The C/- b/b tends to be  deeper and duller. Do you find that? I saw the pictures of your cats  but it is hard for me to imagine how this could apply to my cats as  mine are mainly I based. 

Re SWB and WBs I am still trying to get my head around it. I have  been looking at the coat pattern of the kittens I have produced with   great interest. See this litter - in the 27 and 28 feb blog entries you will see pictures of the  little babies.  There are 2 kittens in that litter that displayed  very even colour and then there is another one although lighter in  colour displayed a more tabby pattern.  I am wondering whether the  Swb or wb gene cause that eveness in colour??  That very even colour  kitten (Simba) is now fully grown and this is his coat pattern and still  not a single bar in sight :)  Blu Kaleidoscope (the cb/cb B/b) that I  sent you the DNA results for is also pretty even. Attached (linked below) are his pictures. He is Columbine’s son. I think you will like the look of  him too.
Blu Kaleidscope 3 photos of


Hi again Isa
I do like your Columbine
If you look on our web site
Mercuryis the cat Strathkirk   (his sister Meerani came to Horizons)  imported and for us all he sets the Canadian Standard.
Re eyes I have not spent a lot of time with that so anything you have is most interesting. I suspect that with our views on breeding back to the Burmese we may well lose some of that quality.
Re: Tipping, have you read the article  I have posted on our web site on that.
Genetics of the shaded American Shorthair   genetics 1 page ( not sure of second link)
I am fairly sure of the conclusions but agree it is a struggle.
Re: Kittens posted. It would seem you are getting the kind of early pattern display that is talked about in the Chinchilla and this disappears/is muted as part of the growth of the undercoat. We tend to not see that - -must stress most of out work is with the shorthair. In many cases (for us) the tipped colour does not appear until 8-10 weeks and may still fool us for up to 2 years. - -  but again that may also be due to the fact we are working with a predominance of pointed cats (cbcb).

In your photos you appear to have some spotted cats!!!?? photos between tag Feb 18 and feb 9 0 0 Fuji kittens??
That may contribute to colour variations??

I notice also that in the kitten grouping under 1 Mar 2007 that one of the kittens does not display the "Brick" nose leather (Dark girl??). It is our understanding that the brick nose is a signal that the cat is agouti ,<A/->  and that  a coloured nose is a <a/a> cat.  - - (A  general understanding -  that is a "smoke".) This brick nose sometimes take time to become clear and may not be complete, but we have not encountered otherwise. Thus the kitty I am speaking of,  is different from it's siblings???.
Robinsons speaks to the sometimes uneven colouring in smokes. I can not find the exact ref page at this time but we have observed this often as you can see in our photos.
I can not find any technical ref to the brick nose  - -just our observations  -  -any thoughts on that?? regards

dec 14

Hi Ivan
Thanks for your comments re my website. I am trying very very hard to document things with photos as a picture speaks a thousand words .

Re Mercury I love his coat. That is exactly what we are all striving for here. The true semi longhaired coat with not much undercoat. Columbine and her son Kaleidoscope have very similar coat so I am very happy. I am trying to replicate this coat by keeping Kaleidoscope as a stud. Hopefully his babies will be the same.

Re eye colour here is the xls I prepared from years ago. Basically it goes through the probabilities when you mate cats with different eye colour.  The more “E “s there are the more yellow the eye colour. So eeeeee will be blue eye colour and EEEEEE will be very dark yellow. Have a look and see if you could understand it. I didn’t really prepare it to send it to people so it may be confusing.  My conclusion is basically that a Blue green eye colour cat when mated with a yellow green eyed colour cat produces the most green tones.  So basically if you have bad eye colour in your cattery you can fix the situation by introducing a blue green eye colour cat to fix your eye colour. I started investigating this my when Momo’s eye colour stayed yellow after he turned 18 months. He is not  a breeding cat but I was just wondering what I could do to fix eye colour if I had to in the future.  I don’t have an issue with eye colour at this stage but you never know when this sort of info will come in handy.  Columbine has blue green eyes so I am expecting Kaleidoscope to have brilliant eye colour when he is fully grown J Lucky me.  PS I have locked the data in the worksheet so if you want to post it on the website or something people cant change the content.

Re the kitten with the black nose. I ve had this question in my mind for years and I am so happy that there is at least one other person in the world that is interested in finding out why this happens. I have seen a few black nose cats the last few years but just cant explain what is going there. I have another person suggesting to me that black nose means a/a but that little kitten I have was definitely not smoked and you can see that in the photos when she was born. I think i can see slight barring on the tails can you??? I cant tell which one was the black nose but she was one of the dark ones. My understanding with smoked is that the hair shaft should be around coloured but this kitten was quite “white” looking see middle cat at 12 weeks. So may be there are different degrees of “smoked “. So may be there are a/a cats that are quite sensitive to the I inhibitor and thereby may still appear very white, eg may be the white will go up the hair shaft a lot more thereby blocking the color more to give it a more shaded look rather than the tradition smoked look??  If this is true then it can be very helpful in getting rid of the barring so to speak. I had a really quick look at your ASH page and it seems that you have some similar findings???   But another thing I saw in this litter was that the brother to the black nose kitten also had and still has a really clear coat.  He was born with a very similar coat pattern to the dark nose kitten as you can see in the pictures but he didn’t have a black nose but a normal red nose.  As I have kept him as stud I had him DNA tested and he is A/A no question about that.

Re spotting. I must confess that I have not looked into spotting genetics much but I would say that the kitten you saw that appeared spotted is just a mackerel tabby with broken lines may be? see here What do you think? You can hardly see the broken lines now and I guess with longhairs it is very hard to tell. She is one of my queens named Lotus.  See this picture gallery Lotus is the kitten with the pink collar. You will also see a few pics of the black nose girl, she has the purple collar.

By the way just out of interest, what colour do you think is that pale little kitten in the following pictures? and and and and
PS may be I should post some of this interesting genetics chat on my website too J

Hi Isa


While our web site did not start that way the photographs and text now tend to be the cattery log/diary. It is often useful for review when some new genetic understanding comes about and you can go back and trace it through the lines.

We did not get the xls colour chart for eyes.

Re  Black nose I would bet if you tested her she would be non agouti <a/a>. Thus a  "smoke".

It would be my  (rather recent) understanding that the variation in "smoking" is almost continuous from almost no indication  of silver to what you have  - -and given the  wide banding you have as in Holly
that would seem reasonable to me.  Yes (
there are different degrees of “smoked “) I agree .

I have attached a photo scanned from Gloria Stephen's Legacy of the Cat -  page 59 first edition   that was quite a surprise to me.  Sure is a lot of marking for a non agouti cat wouldn't you say?

There doesn't seem to be a lot of understanding in the worldwide fancy as to what a smoke truly is, - and when I emailed with Gloria, she admitted as much.

Re dinky paws  Ann and I guess Lilac. all others???

You might find
Sekhmet  's  kittens of interest we have put ourself out on the limb here.