STOCKYARD
HORSE  DISCUSSION FORUMS

mamma mia

I believe they can now DNA for grey in Britain but it is not yet commercially available. All of us who DON'T want grey but who have a couple of heterozygous grey mares in the broodie band because they are just too good in all respects apart from the colour, will be waiting eagerly for the test to become commercially available so we can test foals and say by a few months of age whether or not the horse will grey out.

I was reading somewhere -maybe here - that linking the grey DNA test to the overall genome of the horse reveals that all grey horses descended from one common ancestor tens of thousands of years ago, or even further back. I believe they can trace to a common ancestor via the mitochondrial DNA. One horse had a mutation in the ordinary colour genes that caused the complete loss of colour in the hair at an early age, and that single horse bred that colour mutation on until it is evident in nearly all breeds of modern horse. Interestingly, this gene must have gone through further mutations (my assumption) as we now have some lines of greys that go completely white by the time they are four or five, some that stay steel grey until they are over ten, some that go flea bitten grey, etc.

Perhaps that single first grey mutation also had a mutation in the T-cells that attack cancer cells (by coincidence or perhaps the location on the DNA is adjacent) so that all grey horses develop cancer cells/tumours/growths easily whereas the other colours have the very active and normal T-cell production to detect any cancer cells early and deal with them. I am sure there will be further exciting research into this which may well carry over into the understanding and treatment of human cancers.

I've been meaning to chat to Tintara about this and pick her brain on the topic (my knowledge comes from picking brains of people like Tintara!)

Leanne O.

samm

Why pay the money??
If the mare has a non-grey parent it wont be homozygous for grey.

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Shooter Photographics Mihrabi Arabians & Welsh

Trojane

Mamma Mia said: Hi MM, I posted on this recently:
Grey horses are all related! Breaking (genetics) News

In the original paper from Nature Genetics, greying is thought to be due to overexpression of one or two genes (NR4A3 and/or STX17), which promote melanocyte proliferation. NR4A3 is linked with cell cycle regulation (and carcinogenesis). They believe STX17 duplication leads to overgrowth of skin melanocytes and thus melanomas. However the excess growth in the hair-follicle melanocytes depletes the stem cells...leading to premature greying. This theory is supported by the fact young grey horses darken before onset of greying.

I hope that makes some sense!!

Tintara

Have PM'd you Kylie.

Remaani

Cool, i knew you meant him. Lovely boy.

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Time after time......

citygirl

Thanks Trojane ...lol this boy is just a grot of a horse..he loves being dirty !
One reason I'm not keen on greys is if born chestnut..they look a yukky colour while they grey out...{ for a few years that is.. } its like an offish pink colour ! lol other than that..I'd just love a chestnut filly from him

His Sire & Dam are greys, his Dams parents are both grey, and his Sires Dam is grey....lol I dont stand a chance getting a chestnut filly by him do I ???

cheers
Lee

mylittlepony

sorry to say there are a few brown verglas offspring running around but the amount of greys hes produced is amazing!

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Sometimes you’ve got to specifically go out of your way to get into trouble. It’s called fun.

Trojane

MyLittlePony said:
Oh dear...strike him off then! It only takes one and he's out!

And CityGirl, I think your chances are slim... but some of those greys in his family could be concealing G/g combinations. Chestnut may yet break through! Mind you, you'll be the first I know actually wishing for one (though I love my chestnut!!!)

Dreamer

Well his name is Billjim, 16.3 h.h., produced chestnuts and greys. Photo. can be found by searching WHOBAA.

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To Each his Own.

torridonequine

Hi We stand Andalusian Atomico he is an outstanding stallion and although not many stock on the ground i would be surprised if he threw anycolour His dams side is totally homozogious and sire is grey .I own his half sister and she has never given us colour only grey to my black/brown stallion and to another black stallion.
We also have a sec A stallion welsh who has only ever produced grey but he,s only 11.2hh Wendamar Selection .
Go to www.torridonlodge.com - Home to view stallions