# Strange Question: Need example of yellow plus blue dilution?



## YuukikoOgawa (Jul 26, 2013)

So, bit of an odd question, as it's related to something non-mouse-related...

I got in a..."heated discussion" with someone the other day about the alleged "Maltese tiger." It's typically shown as being bluish-grey with black stripes. From what I've learned about mammalian coat colors in mice, I pointed out that I really don't think such a color would be genetically possible due to how the Maltese dilution works. The _stripes_ would be bluish-gray, sure, but not the orange parts. They pointed to examples of Russian Blue cats, and I tried to explain that the way the Maltese dilution works is not by changing the _color_ of the pigment, but rather changing how the melanin is distributed in each hair. Instead of being in one nice even layer, it's concentrated in random clumps, and the negative space in-between creates a dilution effect. So, to the best of my knowledge, a Russian Blue cat is genetically a black cat with the Maltese dilution making it appear "blue."

So if a Maltese dilution gene worked the same in tigers as it did in mice, it would probably wash out the orange parts but wouldn't magically turn them "blue." My problem came up when I tried to find a mouse example showing what that would look like. Finding pictures of blue mice is no problem at all, but I can't find any good examples of what the d/d mutation over _pheomelanin_ might look like. I know it's possible, as I've produced mice with those genetics back when I was still breeding (most of them were brindles, if I remember correctly). But I don't have any pictures left of them.

Would anyone happen to have such a picture lying around?


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## PPVallhunds (Jul 26, 2010)

For mice blue brindle would probably be your best bet for seeing blue genes effect of the yellow pigment.
These describe it and one has a pic as the red parts as a gold to cream colour on blue brindle.
http://tarotrats1.homestead.com/brindle.html
http://www.afrma.org/brindlemice.htm
Allthough that would only be if it was just the blue gene involved rather than a few genes working together.

Wikipedia have a section on those tigers possible genetics
https://en.m.wikipedia.org/wiki/Maltese_tiger#Genetics

However if they did exist I'd imagin they would be along the lines the the silver/blue tabby cats
http://www.tigatails.co.uk/7.html


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## PPVallhunds (Jul 26, 2010)

If this cat from the breeder above was blue diluted it would look the most like the photoshopped photos of the blue tigers
http://www.tigatails.co.uk/resources/_w ... _ebony.JPG

It seems even looking at pics of blue tabby cats some the base colour is more silver with darker markings and some it's more blue with lighter markings, others a bluish cream. So I'd guess alot comes down to selection maby.
https://tse4.mm.bing.net/th?id=OIP.M9a9 ... =4&pid=1.1


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## YuukikoOgawa (Jul 26, 2013)

Yeah, the genetics are a little tricky when it comes to cats...I'm trying to find info on exactly how the Maltese dilution affects pheomelanin in cats, but not too much luck. Most of the "blue" tabbies in those pictures look more like what I was taught were just "gray" or "silver" tabbies (though quite a bit more intense and darker). Most of the "blue tabbies" I've had pointed out to me by my mother (used to show Himalayans and Persians in TICA shows) and her breeder friends had more similarity to blue-point Himalayan or Siamese cats: the points were clearly blue-gray, but the body had a very distinctive pinkish-gray tinge. Like the "blue tabby" example shown on this tutorial:

http://majnouna.deviantart.com/art/Guid ... s-91579716

Then there's the complication of purebred cats (with much more intense selective breeding for very specific shades) versus the type that would more likely crop up entirely on its own in a feral population (which, from personal observation, doesn't seem to be nearly as intense and tends towards more of that "blue on warm beige" shade).

I did check out the Wikipedia page, and it does point out some of the complications that would make the myth rather difficult to pull off. Particularly the non-agouti vs agouti switch and the pheomelanin issue. Honestly, if it was just a matter of the single Maltese dilution, I kind of imagine it might actually be difficult to tell the difference between that and a "white" tiger, given how pale the orange parts might end up (and a white tiger's stripes are usually a bit diluted already, though to a more chocolate shade rather than dark blue-gray).

Of course, most of this is a moot point in the end, as it's scientifically not real to begin with until actual physical proof can be produced. Even white tigers have been proven to be entirely the result of the black market using inbreeding to produce novelties to make more money off of (which is why zoos participating in conservation breeding get really frustrated and discouraged when one of their tigers throws a surprise white cub; it means they're completely unsuitable for that program). Even if white tigers were occasionally produced in the wild, they wouldn't survive to adulthood because that mutation completely ruins their ability to stay camoflauged. As babies, they'd become easy pickings for local predators, and as adults they wouldn't be able to hunt. I really can't see a Maltese tiger having any better chances of survival, either; either variation (the really dark blue-gray all-over or the one that looks like a gold-blue brindle mouse) would similarly ruin their ability to hide and hunt effectively (which, in turn, would weed them out of the gene pool pretty fast).


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## SamOfChaos (Nov 29, 2015)

I know a gene in snakes (corn snake and many othery) does turn orange and red to grey and black stays black (anerythristic).
But I have never see anything like the maltese tiger in the foto from wikipedia.

Edit:
I have an idea. When there is a gene that dilutes the orange to white, but there are still stripes visible. Then there can be a gene that turn the orange to grey without altering (or at least not to much) the stripes. But maybe the gene is only fount in tigers (till now...)

It would be more like a silver agouti mouse, black ticking, brown turns grey.


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## PPVallhunds (Jul 26, 2010)

id imagin if it was real they would be more like the silver/ blue tabby than a proper blue base with black stripes, as you have said the domestic cats have been selectvly bred to be better colour just like with wild mice and show agouti, same colour very different shades. so the man made images are likely way off if it does exist


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## SilverWings (Jan 27, 2016)

SamOfChaos said:


> I know a gene in snakes (corn snake and many othery) does turn orange and red to grey and black stays black (anerythristic).


No idea about the mammal genes but the anery gene in corns doesn't alter the red colouration, it removes it entirely. A bit like how albino animals lack melanin so they have no black colouration, anerythristic corns have no erythrin which gives the red colours. Sometimes you'll hear anery called black albino.


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