Help me guess what breeds are behind my fairly unusual brother and sister

[Echolane]

They were found abandoned in the street, just the two of them, when they were an estimated two days old, so nothing is known about their parents. They were bottle raised by a family with other cats and a dog. I call him Timo and her Gem, short for Gemini.
They are unusually large cats. He weighs 16 pounds and is not overweight, she weighs the same, though she is somewhat overweight.
They have fairly unusual colors. He is a ticked blue tabby, she is all brown.
They have very tiny soft voices.
They have very soft purrs, it’s hard to tell they are purring.
They both have glitter in their coats.
Otherwise they are just nice, well behaved cats.

 

[Willowy]

Oh wow, those are really cool colors! He looks almost grayscale, except for the ruddy shading on his paws. And chocolate and ticked tabby are fairly rare in the general cat population. Are you in the US?

 

[Echolane]

I’m in the US, California just 45 minutes south of San Francisco.

 

[lutece]

They are indeed interesting cats! It looks like one is blue ticked tabby, possibly blue silver ticked tabby, and the other appears to be chocolate.

Can you explain more about the glitter? They don't appear glittered in the pictures.

Because of their colors, ear set, and wedge shaped faces (at least from what I can see on the blue tabby), I think it's possible that they could have some Siamese or Oriental ancestry... although you describe them as having soft voices, which would not be typical of those breeds The chocolate mutation and ticked tabby pattern are both present in those breeds. Since the chocolate mutation is recessive, however, both father and mother would have to carry it. Your cats don't look like purebred Oriental Shorthairs, but maybe there is a cat with Siamese or Oriental ancestry carrying the chocolate mutation on both sides of their family tree. Inbreeding can easily happen in feral colonies or in neighborhoods with free roaming intact cats.

 

[Echolane]

Thanks for the educated guesses. My thinking has long been that there is purebred breeding of some sort, but what? Oriental Shorthair occurs to me too, but as you say the voices are atypical. I also think size is atypical. My experience with Siamese, Balinese goes back too far to have much contemporary relevance but my long ago experience with those similar breeds is that they produce smaller cats and my two are just huge, at lease so they seem to me. I have a feral cat who stays outside and she is about 6.5 pounds, so Timo and Gem are close to 3x bigger!

As for glitter, I accidentally deleted the best photos, but here’s one of Gemi that was spared. She can turn almost completely “no color” if the light is just right. I’ll see if I can find another.

 

[lutece]

I've seen some very large Orientals (very long and tall), and I expect that such cats could produce even larger offspring if they were combined with unrelated random bred domestics. Anyway, 16 lbs isn't a crazy huge size, we're not talking about 30 lb cats

 

[Willowy]

That's a LOT of recessive genes. If not done on purpose by a breeder, it's likely they have a lot of inbreeding in their background.

I'm not sure how to tell the difference between "glitter" and a normal shiny kitty coat, so I won't comment on that.

 

[lutece]

That's a LOT of recessive genes. If not done on purpose by a breeder, it's likely they have a lot of inbreeding in their background.

Only chocolate is recessive, ticked tabby and silver are dominant. Was there something else recessive involved, that I didn't catch? (Other than solid and dilute, which are common enough that I don't think it counts?)

 

[Echolane]

According to a Google search, two cat breeds that exhibit very soft voices are Abyssinian and Bengal. Speaking of soft, Gemi’s coat in particular is exquisitely soft. I mean really soft. And it’s her coat that glitters so much. I was just reading up on Bengals and they have very soft fur and soft voices and glitter. One breeder site says their fur sparkles in sunlight. If that is the case, Gemi qualifies. Her entire coat sparkles in the sunlight and there is a peculiar absence of color. I want to use the term crystal to describe it. I didn’t check up on Bengal size. Need to do that.

I think Abyssinians are ticked, is that so?

 

[lutece]

According to a Google search, two cat breeds that exhibit very soft voices are Abyssinian and Bengal. I think Abyssinians are ticked, is that so?

Abys are ticked, but your cats really don't look anything like the Abyssinian breed. Bengals are not ticked (and your cats don't resemble Bengals either). Neither of these breeds come in chocolate.

 

[Willowy]

Only chocolate is recessive, ticked tabby and silver are dominant. Was there something else recessive involved, that I didn't catch? (Other than solid and dilute, which are common enough that I don't think it counts?)

Yeah, I was thinking that the combination of chocolate, dilute, and solid all in the same litter seems like an awfully big coincidence. So both parents would have to have a fair amount of recessive genes in common.

 

[lutece]

Yeah, I was thinking that the combination of chocolate, dilute, and solid all in the same litter seems like an awfully big coincidence. So both parents would have to have a fair amount of recessive genes in common.

Dilute and solid are really common though. If one parent was solid blue (for example) and the other a carrier, each kitten gets a 50% chance to be solid or dilute... just like the chance with a dominant gene. These alleles are widespread and this wouldn't be an uncommon pairing... I just don't see it as significant.

Chocolate however would indicate probable inbreeding, due to the rarity of the mutation.

 

[Echolane]

I’ll have to guess a lot about how to interpret the technical details of your conversation on the dominant and recessive genes needed to produce their colors, It does sound like you both would conclude that there is a good chance that inbreeding is involved. But not necessarily on which breeds. If you consider the two cats independently. and knowing that brown is recessive then Gemi has to have brown on both sides of her pedigree. Or Am I being careless with terminology, is chocolate and brown interchangeable? Either way, which breeds produce her color? Burmese is the only one I know and she doesn’t look Burmese. But you’ve said Oriental Shorthair, so that sounds plausible. Still, I don’t imagine brown is that common. I remember our local Humane Society which sponsored their foster care family told me they see a brown cat only every five years or so.

And in the case of Timo, I gather his color can be produced without inbreeding. Which probably means any random breeding might produce his color and pattern?

 

[lutece]

[...] is chocolate and brown interchangeable? Either way, which breeds produce her color? Burmese is the only one I know and she doesn’t look Burmese. But you’ve said Oriental Shorthair, so that sounds plausible. Still, I don’t imagine brown is that common.

Chocolate is a different gene than sepia (Burmese color restriction).

• Chocolate is part of the "brown" series: Brown (Chocolate and Cinnamon) | Veterinary Genetics Laboratory
• Sepia is part of the "colorpoint restriction" series: Colorpoint Restriction | Veterinary Genetics Laboratory

Your cat appears to be chocolate, not sepia. A sepia (Burmese sable) cat would have slightly darker "points" and slightly lighter body color, while your cat's color appears uniform all over.

The chocolate allele was first seen in the Siamese breed. It is a very rare allele in the general domestic cat population, so it's very unlikely for a random bred cat to get two copies of this allele if the parents are not related to one another. Siamese do come in chocolate point, and Orientals come in many different variations on chocolate. It's seen in some other pedigreed breeds, but most of them don't look similar to your cats.

And in the case of Timo, I gather his color can be produced without inbreeding. Which probably means any random breeding might produce his color and pattern?

He appears to be either blue ticked tabby or blue silver ticked tabby, I would lean towards blue silver ticked tabby from his appearance -- does he have a white undercoat?

Ticked tabby is uncommon in random bred cats, although more common than chocolate. Ticked tabby is fairly popular in Orientals, however, and Siamese also may have an underlying ticked tabby pattern (even though Siamese are typically solid pointed and not tabby pointed, it's useful for them to have underlying ticked tabby genetics, because ghost tabby markings are less visible that way).

 

[Echolane]

I finally looked at photos of Oriental Shorthairs. It took me awhile because I had seen them at a cat show decades ago and was left with the impression that they were like solid color Siamese. I am Clearly way out of date as they seem to come in many many colors, including ticked colors and brown And it’s easy to imagine Oriental in their background. I can see there is a certain resemblance in the shape of the face in photos that are older. As for the more modern looking Oriental, I am greatly relieved that my two cats don’t look too modern with huge ears coming out of the sides of their heads and which remind me of something that could fly! Nor do they have super skinny bodies, though they are quite long in the body to my eye, and they weigh more than the standard suggests. Timo is especially outgoing and will greet strangers at the door. Gemi is less bold, but not shy. So it does seem plausible that they have Oriental somewhere in their pedigree, probably on both sides. I am finding this quite interesting!

There must be something else of interest that would explain their tiny voices and soft purrs and unusually silky coats With glitter. It baffles me that these two siblings would wind up abandoned on the sidewalk when so young. Was their mother interrupted in moving them? Did someone dump them? An unsolvable mystery....

 

[Echolane]

I should add that Timo seems to have a gray undercoat. It looks much the same color as his outer gray and is not light and certainly not silver, or as I would imagine silver to be. Here are a couple more photos of Timo that give better views of his underpart.

 

[Willowy]

It does sound like you both would conclude that there is a good chance that inbreeding is involved. But not necessarily on which breeds.

There doesn't necessarily have to be any breeds involved. Most cats have no breed background at all. These recessive genes can show up in the general cat population; although chocolate is rare it's not unheard of. And maybe with San Francisco being somewhat higher-income than usual, there might be a higher chance of purebred background. . .but I can't really see any obvious breed in them. So they may be domestic shorthairs who really hit the genetic lottery.

 

[Echolane]

You are almost certainly right. I’m not trying to make them into something special, but I was inspired to raise the topic here because just this week my family visited and we were all speculating about the ancestry of my two cats. The conclusion was that If it were just one or two characteristics that seemed a little outside the average then it’s easy to assume the randomness of their breeding, but in their cases so many things seem a little outside the mean ( tiny voices, tiny purrs, extra soft coats, glitter, larger size and fairly unusual coat colors) that it just seemed seemed like a large number of oddities for two cats. But of course there is always room for these things in the lottery of genetics.

Thanks for an interesting discussion.