# Homozygous question!



## CLaPorte432 (Jan 3, 2012)

I dont see why not. Although i personally have never seen a homozygous splash or sabino horse.

Sabino, splash and frame are the 3 overo genes.

Frame you know, in its homozygous form is fatal 100% of the time.
_Posted via Mobile Device_


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## NdAppy (Apr 8, 2009)

CCH on here owns a horse that is homozygous for splash CLa. I know there are more out there now that we have some splash tests.


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## CLaPorte432 (Jan 3, 2012)

NDAppy, your right! Do you know if Gunner is homozygous for splash? I believe he is deaf too. Are homozygous splash horses more prone to deafness do you know?

Im sure there are quite a few out there. But i never see anything advertised as "homozygous for the splash/sabino gene" its always for tobiano.. ;-)
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## Reno Bay (Jul 8, 2012)

If being homozygous-dominant isn't fatal (as is the case with frame overo) then I don't see why horses wouldn't be able to be homozygous-dominant for multiple patterns.

If you bred a SbSb Spsp horse with a Sbsb SpSp horse, you could theoretically come out with any Sb- Sp- foal, including homozygous-dominant for both.


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## NdAppy (Apr 8, 2009)

I don't believe that there has been much advertising about it yet as the test is still so "new" so to speak. 

I believe that the Gunner line is SW2 carriers, and it is beleived that SW2 is embryonic lethal.


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## Reno Bay (Jul 8, 2012)

Like I said...IF being homozygous-dominant isn't lethal...


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## NdAppy (Apr 8, 2009)

:wink: when I typed out my response your post wasn't there.

SW1 can and is homozygous. SW2 and SW3 are thought at this time to be embryonic lethal.


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## Reno Bay (Jul 8, 2012)

That's odd cause your post was 6 minutes after mine. I seem to have a few forum issues XD


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## NdAppy (Apr 8, 2009)

I had the screen open for a while as I got side tracked with my kids.


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## MangoRoX87 (Oct 19, 2009)

I always wondered if Gunner was homozygous, since most of his goals seem to have the same markings as him. Or at leat from what I have noticed.
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## TexanFreedom (Apr 2, 2012)

Somebody I know said that max white sabinos are ****, and 'regular' sabinos are always heterozygous? I didn't think it was true, but there is a possibility it could be true. I don't think so. 

I think with overos (broadly speaking), you have to have them tested to know for sure.


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## Chiilaa (Aug 12, 2010)

The problem is that sabino has only had one type isolated for testing, and lots of horses with a sabino phenotype have tested negative for sabino 1, which is the only testable one. The same goes for splash - the test has been out only a few months but already there are lots of horses with splash-eque markings that have tested negative.


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## MangoRoX87 (Oct 19, 2009)

So are there different strains of each of those??


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## Chiilaa (Aug 12, 2010)

MangoRoX87 said:


> So are there different strains of each of those??


Yes. Currently there is only a test for Sabino 1, and for Splash 1, 2 and 3.


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## Chiilaa (Aug 12, 2010)

MangoRoX87 said:


> I always wondered if Gunner was homozygous, since most of his goals seem to have the same markings as him. Or at leat from what I have noticed.
> _Posted via Mobile Device_


I don't think he would be. If I recall correctly, his line is splash white 2 (I think) which is theorised to be embryonic lethal homozygous.


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## TexanFreedom (Apr 2, 2012)

Chiilaa said:


> The problem is that sabino has only had one type isolated for testing, and lots of horses with a sabino phenotype have tested negative for sabino 1, which is the only testable one. The same goes for splash - the test has been out only a few months but already there are lots of horses with splash-eque markings that have tested negative.


I have always wondered about this to myself- are there different types of sabino, because there is so much variation in horses that are sabino; the 'sabino roan' commonly seen in clydes, and the crisper jagged belly and face markings type ect.


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## Chiilaa (Aug 12, 2010)

TexanFreedom said:


> I have always wondered about this to myself- are there different types of sabino, because there is so much variation in horses that are sabino; the 'sabino roan' commonly seen in clydes, and the crisper jagged belly and face markings type ect.


A lot of people who have done a fair bit of research, and others like me who feed on their research, are leaning towards Clydesdales being dominant white rather than sabino. The markings are just too crisp and flaky. That's the only way I can describe it - dominant white markings are crisp and flaky lol. 

There are definitely different types of sabino though. There are plenty of horse that have tested negative for sabino 1 but still display sabino markings. Sabino 1 seems to be only in certain breeds (I can't name them off the top of my head, will come back to this thread later today).


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## TexanFreedom (Apr 2, 2012)

That's really cool.


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## kctop72 (Aug 25, 2011)

ok, can someone please help me out with embryonic lethal homozygous? Tried looking it up but need someone to put it in a language I can understand or at least a good website to reference!!!


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## NdAppy (Apr 8, 2009)

Embryonic lethal means that the fetus dies as an embryo.


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## TexanFreedom (Apr 2, 2012)

I think it' pretty easy to assume that's what it means (what NdAppy said) by just looking at the context. I had never heard that before and I assumed that's what it meant.


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## MangoRoX87 (Oct 19, 2009)

Well I didn't really understand 100% what it meant either.


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## LuvMyPerlinoQH (Jun 21, 2011)

NdAppy said:


> :wink: when I typed out my response your post wasn't there.
> 
> SW1 can and is homozygous. SW2 and SW3 are thought at this time to be embryonic lethal.


 
This is very true my friend who owns Spooks Gotta Whiz, tests him and his foals for this with every genetic panel testing.


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## kctop72 (Aug 25, 2011)

I guess I should have asked my question differently. I assumed the embryonic lethal meant the fetus dies as an embryo, what I'd like to know is why and if there's a good website someone can refer me to in order to read up on it?


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