# Homozygous Grey vs Heterozygous Grey <PIC heavy>



## Chiilaa (Aug 12, 2010)

Statistically, homozygous greys do seem to whiten earlier. HOWEVER - those statistics are collected from hundreds of horses, and there are MANY horses that defy the trend. So while the statistics suggest it, using the time taken to grey out to determine zygousity is never going to be a foolproof method.


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## GhostwindAppaloosa (Jun 3, 2011)

easiest way to figure out is to do a UC davis color test on her for grey. its super quick and all you have to do is send in hair. We have a heterozygous grey mare. She didnt grey out until 11 and was still pretty black at 9. she has had 4 foals. two grey. two not. sire on all four was not grey


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## trailhorserider (Oct 13, 2009)

I think what you said is generally true, but I have no real expertise on the matter. But I DO own two grays at the moment, and I'm sure they have to be heterozygous because each has only one gray parent. They are a mare and her colt and they are both slow to gray out.

The mare I have only had a couple of years, but she is going on 18 and she still has some dapples on her flanks and the underside of her belly. Her colt is 1 1/2 years and most people still don't believe he is a gray but I'm sure he is because he has roaning on his face and white in his tail. But other than that, he looks like a bay at first glance. His sire was chestnut.

So I guess what I'm saying is in my "sample of two," heterozygous grays do tend to gray slow. :lol:


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## SunnyDraco (Dec 8, 2011)

I think that if we did a UC Davis color test, that I would definately also test for agouti. Glory is bred to a solid homozygous black arabian, so the agouti would affect whether she would produce a bay or black foal.

I can conclude that Misty has atleast one agouti gene that could be passed to Glory, because of her first foal. The first foal -pictured with 5yo Misty- was by a solid black (Ee) qh stallion, and when she grew up, the filly was then bred to a solid homozygous black and produced a beautiful bay colt. He didn't inherit his dam's grey gene, and stayed bay 

The end of April can't get here quick enough to find out what is growing in her belly


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## trailhorserider (Oct 13, 2009)

Very exciting! You just HAVE to post pictures the day that baby pops out!


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## SunnyDraco (Dec 8, 2011)

Maybe for some more reference, these are Misty's first two foals. Both are heterozygous grey by the same black quarter horse sire.







Chip is on the left, 4 years old, was a dark chestnut foal.
Saigar is on the right, 5 years old, was the foal pictured at Misty's side

Chip went through a large range of weird colors before he turned nearly white as a teenager. Saigar went light about as quickly Glory did, but retained some darker areas just like Glory did.


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## SunnyDraco (Dec 8, 2011)

trailhorserider said:


> Very exciting! You just HAVE to post pictures the day that baby pops out!


 
That I shall!:happydance: 

Here is what what looked like on Jan. 4th with her growing tummy.







^^finally, Misty is *behind* Glory :lol:







Yes, she is fat and over weight, has been on a diet for two years (she gets fat from looking at food).
Not bad for an 18 year old maiden mare though :lol:

My avatar is the sire of the coming foal


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## SunnyDraco (Dec 8, 2011)

here is Chip when he was 8yo








Then when he was 14yo









Saigar when she was 7yo









Both of them could only have had received a grey gene from their dam, Misty. Saigar went light so much faster than Chip, who did eventually get to a light grey... :lol:

I still think that Glory could be heterozygous grey (I really do hope). But since neither her of her dam's other foals got more than a few flea bitten spots, would that have actually have come from her very flea bitten sire? I have no idea why some grey horses get heavily flea bitten and others do not. Glory's sire was a heterozygous grey that was quite flea bitten, does Glory's flea bitten body then mean that she is a homozygous grey because her sire gave her the grey gene as well as her seemingly homozygous dam?

Where do flea bitten spots come from genetically?!? Is it linked with a particular horse's grey gene, or are some just more prone to becoming flea bitten than others without being linked to a particular horse's grey gene?


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## Country Woman (Dec 14, 2011)

Very nice grey horses


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## Chiilaa (Aug 12, 2010)

Again, the link seems to be that heterozygous grey horses have a tendency to have more flea bites. HOWEVER. The study was very broad, and the results were a trend, not a rule. Add onto that - through my own observations, I feel that Arabs are more inclined to be fleabitten than a lot of other breeds.


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## SunnyDraco (Dec 8, 2011)

^^^ thank you. I wonder if there is a genetic marker that leads horses to be flea bitten? Not that it has been uncovered as of yet LOL
_Posted via Mobile Device_


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## SunnyDraco (Dec 8, 2011)

I just double checked the pedigree of my cousin's very fleabitten grey arabian, and she is also a heterozygous grey. So, maybe the heterozygous grey crossbreeds of arabians are less likely to become fleabitten than the heterozygous purebreds? 
I wonder if that can be tested?
_Posted via Mobile Device_


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## Chiilaa (Aug 12, 2010)

I still think there is something in in Arabs that encourages fleabitten greys  But, unfortunately, it won't be something we find in a hurry. To be able to test it, they would have to isolate the part of the DNA code that controls it, and then test for it in a variety of horses. While I would love to see this, I would love to see plenty of other tests long before this one


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## MHFoundation Quarters (Feb 23, 2011)

Interesting thread. I'm waiting for results of my grey mare's test. The first grey on our farm (other than outside mares) in 30 years. She is 10, still pretty dark and not fleabitten. Got my fingers crossed she's homozygous, take the guess work out of it when registering her foals lol! Her first, my weanling, is bay going grey.
_Posted via Mobile Device_


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## Allison Finch (Oct 21, 2009)

I know very little about color genetics. All I know is that the stallion in my avatar was homozygous. I started working with him at age seven and he was already pretty white. His foals were greys of every color possible of grey.


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## MangoRoX87 (Oct 19, 2009)

I find this quite interesting Rosie is heterozygous, she has had one sorrel filly and one grey colt. She has been fleabitten for...gah...nearly ten years I think. I saw a picture of her as a 4/5 year old, and she was a dappled..

I'm thinking Dream is homozygous. She is fleabitten on top of the dapples. She was bred to a roan, and we got Sassy, who nobody seems to think is a grey


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## emilienrocket (Jan 10, 2012)

Rocket is fleabiten gray, her mom was gray and her dad was black and white paint. shes 8yo and almost all white.

this is a few years ago 










Now


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## GhostwindAppaloosa (Jun 3, 2011)

Baby in 2009 at 10 years old... 









and in 2010


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## NdAppy (Apr 8, 2009)

Betting that leopard foal greyed out as well... Sad to have such a wonderful pattern disappear like that.


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## Gidget (Jan 19, 2010)

I have no clue what she will look like. I only know her the dam is and not the sire but the sire I am guessing is grey! Her mother was a bay.


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## GhostwindAppaloosa (Jun 3, 2011)

baby is a heterozygous grey. 50% of her foals do not grey out. The ones that done always come out bay and are just as lovely. I personally think that greys are beautiful and her babys keep spots until 10 just like she did.


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## GhostwindAppaloosa (Jun 3, 2011)

Gidget.. your girl looks like a roan.. not a grey? Greys tend to have "goggles" do you know if either parent is a grey for sure?


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## Chiilaa (Aug 12, 2010)

GhostwindAppaloosa said:


> Gidget.. your girl looks like a roan.. not a grey? Greys tend to have "goggles" do you know if either parent is a grey for sure?


The horse Gidget posted is an Arabian, so roan isn't possible. Aside from that, she definitely looks like a grey to me.


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## NdAppy (Apr 8, 2009)

Ghostwind - Gidget's horse is a grey.


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## NdAppy (Apr 8, 2009)

*pokes Chiilaa*


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## Gidget (Jan 19, 2010)

yep she is a grey  Her mother is an arab/welsh and her father is an and arab and I am guessing he was the grey since the dam is a bay


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## Piaffe (Jan 11, 2010)

He was a grey for sure...I remember the prev. owners telling me  I wish I could have looked at him,but they said they had to move him for some reason...? 

edit: I just realized how old this thread is...lol. Sorry


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