seattlesibe wrote:

There was a guy named Randy from Wyoming on here over a year ago and he was a breed historian of sorts, super smart guy--I miss having him here, and I'm pretty sure it was he who said that in the Husky eye color of each eye is determined genetically independent from one another unlike the case in most animals, rendering bi-eyed genetically normal, or not an abnormality.   So, not the same as heterochromia.

I wish I could find that thread.

Hmm, I will do some reading into this. Would be great the see a different opinion on it!

Hmm, I'm not so sure that's correct,  theoretically.  

If we are discerning what is abnormal then by necessity you have to consider what is normal.  The default sets the table to distinguish variation or deviation.  

So, if two different color eyes is normal in the breed, then two same color eyes is Not normal in the breed....because there can be no normal as far as eye color.   Neither is "normal" because normal contains no default if this is true.   Deviation requires a default,  by definition.  

Heterochromia is the term for a genetic deviation in the determination of eye color.

This can not be true in the Husky IF homochromia is not the default.  

Hence, bi-eyed simply refers to the phenotypic expression,  while not referencing the normality of any genotype.

I'm pretty sure this plays in to why this is not considered disqualification in the show world for the breed standard, whereas a heterochromic doberman would be disqualified,  I'm guessing.

Sorry for typos. I'm on my phone on a bus. All clear now.

I think we are perhaps confusing genotype normality (defaults) from percentage of phenotype expression in the population (statistics).

I think i am focusing on the literal definition of heterochromia, a difference in coloration in two anatomical structures or two parts of the same structure which are normally alike in color.

So in my mind, no matter what the cause of two different coloured eyes, it is referred to as heterochromia, simply for the fact that the eyes are two different colours.

Thoughts?

Right, so just phenotype, the actual expression. Got it.

The real question is whether or not it is true that eye color in the breed is determined independently or not, thus, whether or not homo- or hetero- chromia is normal, or default.

That was my suspicion, you were focusing on effect, and I on cause.

Yeah. I *think* in the lab, we would refer to any type of different coloured eyes as heterochromia, so in tgis context, all bi-eyed are heterochromia, but not all heterochromia is a genetic abnormality.

I definitely am intrigued by this now Especially since Kesler is bi-eyed. Going to do some in depth research now

Awesome,  I was hoping you were a biology study with access to to resources

I conferred with my partner who is a molecular biologist but he hasn't responded yet.

Basically,  we are trying to find the reason *why* bi-eyes, or heterochromia, is so disproportionately expressed in this breed compared to other breeds.    

Sound right to you?

Seems there could be two major explanations:

1) it has indeed become genetically accepted, meaning that heterochromia is just as normal as homochromia.   Or, the genotype of the breed has changed or adapted. Eye color is determined independently,  not together as a pair.

2) the genotype has not changed or adapted, and homochromia is default,  normal. Heterochromia is a genetic abnormality in the breed like in humans, other dogs, etc. But, this particular phenotype has been selected for repeatedly, creating a higher proportion of these genes in the breed gene pool.  It's been normalized by phenotype,  not genotype,  as it is still a genetic abnormality,  or mutation...etc.


How does that read for you?

Thank you by the way.  I'm loving this conversation.  

Oh, if you're on a computer try searching here for "research grant", "hetero or homochromia" other thread should pop up.

I am loving this too! Love topics that get the wheels turning. I'm on my phone at the moment so will do the search tomorrow.

I think you've hit the nail on the head regarding what the ultimate question is.

I think I'll also delve into some veterinary genetics journals and see if I can find some studies that explore this topic.

This is going to be fun!

God speed

Just want to throw this into the eye color discussion (just because) - Blue eyes in the breed is not actually recessive but the gene(s) that cause blue eyes in the breed are as of yet undiscovered and unknown and the "sp" gene (piebald) can affect eye color and parti-eyes may or may not be linked to that gene.

It is not referred to as Heterochromia in the dogs.

/end random comments

So I guess my follow up to that would be:

What is the reason for the term not being applied specifically to huskies?  Based on the definition, any colour differentiation would be refered to as heterochromia.  Is this just a "best practice" based on people, specifically people in the dog breeding world?
I am legitimately curious about it!  Just because I have no experience in dog genetics. And in nonspecific genetics, we would refer to any eye colour differentiation as heterochromia, regardless of the species of the affected.

Thoughts?

I don't know for certain but I don't think the term is used to describe two different colors in eyes in animals not just specific to the breed.

I want to say because science is the reason the term isn't used but I don't actually know. In the talks I've had with my red girls breeder about genetics and what little research I used to do in it in my own - eye color and eye color inheritance is just widely unknown (as far as I know) in the breed. There are very few studies regarding eye color inheritance.

More studies are being done regarding coat color in the breed and that is what I'm slightly more familiar with (but in very generic and basic terms and understanding and what I've learned on my own and via mechtas breeder as she and her dogs have been involved in many of the studies)

So complete heterochromia is the scientific term for two completely different coloured eyes, there was some discussion earlier in the thread regarding whether the term applies specifically to huskies, as bi-eyed huskies are not considered to have genetic abnormalities.

My point about the term was that it describes the actual appearance of the eyes, rather than the reason behind it (genetics/acquired/magic ect).

So now we are trying to find the reason why bi-eyed (or heterochromia) is so much more common in huskies (and other certain breeds) than the vast majority of other dogs.

Basically, Jeff and I have taken this discussion to scientific levels to find out the reason behind bi-eyed huskies.

We seem to have that common interest

Also, just wanted to note, I would never use the term heterochromia in every day conversation When people who are not familiar with huskies ask about Kesler's eyes, I just simply say he is bi-eyed.

I get so many people asking me if he is blind in that eye....i guess it is a common misconception about bi-eyed dogs/animals/people.

Anywho....lunch time

I've not heard the term "bi-eyes" specific to the breed. I know other breeds that have it and use it.

I know genes like merle and (my lesser understanding of piebald) could have something to do with eye color.

Merles have blue/bi eyes (relevance being many breeds with merle also have bi eyes) and I know things like extreme piebald affect pigmentation which brings with it health problems (deaf/blind).

I didn't mean that the term bi eyes is specific to the breed.

Just doing some research as to why bi-coloured eyes are more prominent in huskies

Apologies then. Lol I apparently am incapable of understanding English today.

lol, no worries, we all have those days!

I was just getting confused and was about to go re-read what I had written previously

I swear I should not be allowed to use a phone while sleeping lol.

Ahahah,, you and me both!

Ceara, I'm excited to see you back. Thanks for helping out. I was gonna hit Jen up today to maybe tip you off on this conversation.

Barczewska wrote:

I didn't mean that the term bi eyes is specific to the breed.

Just doing some research as to why bi-coloured eyes are more prominent in huskies

That, plus whether or not it is a genetic f' up (defect, mutation.....?? proper scientific term??) in a Husky like it would be in a human; is it the default for the pair of eyes to be the same color in a Husky?

^^ That




Did you manage to get the input of that molecular biologist yet Jeff?

I haven't had time to do that search yet (been scrubbed in to a cleanroom all day, without a computer), but hopefully my phone will co-operate and let me search it at home.

Ha, no.  He was overwhelmed with work yesterday and was in bed by 8:30, and I got home from work an hour later.  

I'm pretty sure his suspicion would be that it is just a case of the heterochromia phenotype gone wild, through diligent selection by breeders over the years.  

But, to me, that is more of an explanation for the predominance of blue eyes generally, not specifically heterochromia/bi-eyes.   That, to me, seems more of a behind the scenes genotype issue considering how uncommon it is amongst animals generally and how common it is in this one breed of dog.

seattlesibe wrote:

Ceara, I'm excited to see you back.  Thanks for helping out.  I was gonna hit Jen up today to maybe tip you off on this conversation.  

Well thank you sir! I have missed you and your witty banter! Jen text me yesterday about the black puppy thread and I was browsing and found this. if ever you need or want to get a hold of me yourself I can send you my number, email Facebook... Whatever. Let me know.

Somewhere I think there is an eye color article in Debbie color group on Facebook but searching is hard to do on a phone...plus lazy