New scientific articles on color and genetics

[aethervox]

These articles were recently published and are (I believe) free to view/download.

The first one is about a new Dominant White mutation:

De novo mutation of KIT discovered as a result of a non-hereditary white coat colour pattern - http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2052.2010.02135.x/full

The second one is about the effect mutations in pigmentation genes have on other parts of the horse.

Pleiotropic effects of pigmentation genes in horses - http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2052.2010.02116.x/full

The final one is, to me, the most interesting, because the researchers were able to find DNA in the bones/teeth of historic thoroughbred horses, test it and get their color genotypes

Accurate Determination of Phenotypic Information from Historic Thoroughbred Horses by Single Base Extension - http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0015172

I did have to e-mail the first author on the last paper, though, because he states that the cream gene doesn't exist in the Thoroughbred. I await his response!

[going4stamina]

Last night, I was watching the Legends interview with Jerry Bailey on HRTV and started wondering if Cigar's infertility might be related to his tail/eye color. When you have something like that, you just never know what other genetic changes are part of the package.

[Jorge]

Thank you so much for the valuable references.

[accphotography]

Cigar's eye color isn't at all unusual IME. Also I've seen his tail color on many, many horses with no apparent fertility issues.

Yet another DW mutation eh? No surprise there. maybe people will eventually start seeing and believing that these mutations DO happen and are actually becoming quite common.

[aethervox]

One additional piece of information. I know that Bend Or has been considered a suspect for hiding the cream gene.

According to the third article Bend Or's genotype was A/A e/e cr/cr

[Sailor Kenshin]

Last night, I was watching the Legends interview with Jerry Bailey on HRTV and started wondering if Cigar's infertility might be related to his tail/eye color. When you have something like that, you just never know what other genetic changes are part of the package.

I'm playing catch-up here and can't tell from photos and videos what was unusual about Cigar's tail/eye color. From what I can see he's just an ordinary bay.

[accphotography]

As I mentioned, I never saw anything unusual about his eye color except maybe this, which is totally normal and common:




His tail just has a bit of a silvery tone at the bottom:

[Sailor Kenshin]

A big red 'x'?

[accphotography]

Webshots.

[Sailor Kenshin]

Oh, yeah---grizzled tail.

[going4stamina]

ACCT, I think it unlikely that the color has an impact on the fertility, but...there is always a "chance", when there is something slightly different, that it can also be an indication of other genetic differences. That being said, a lot of other possibilities on why Cigar is infertile.

[color]

One additional piece of information. I know that Bend Or has been considered a suspect for hiding the cream gene.

According to the third article Bend Or's genotype was A/A e/e cr/cr

Hiding the cream gene? What makes you think so? I do not see where he could hide a cream gene.

[aethervox]

One additional piece of information. I know that Bend Or has been considered a suspect for hiding the cream gene.

According to the third article Bend Or's genotype was A/A e/e cr/cr

Hiding the cream gene? What makes you think so? I do not see where he could hide a cream gene.

I've read several threads on different forums regarding the origin of the cream gene and how it could hide for generations. Several people mentioned that Bend Or might have been 'hiding' the cream gene, and that's why I posted that he didn't have the cream gene.

I did e-mail the first author of the article regarding his statement that cream doesn't exist in Thoroughbreds, but have not yet received a response.

Maybe they could start a study trying to trace the cream gene?

[Pan Zareta]

Accurate Determination of Phenotypic Information from Historic Thoroughbred Horses by Single Base Extension - http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0015172

I did have to e-mail the first author on the last paper, though, because he states that the cream gene doesn't exist in the Thoroughbred. I await his response!

Please let us know what he has to say. I checked the 2003 report by Mariat et al. re. mapping the cream gene. It makes no such statement.

Fwiw - I suspect this project was born from the need to discriminate between samples, all alleged to be from the remains of Eclipse, but which proved to have come from two or more different horses. Using coat color for this purpose carries a high risk of false positive identification, but it may have been the only viable option.

Did you notice that their source for the coat color of the 13 subj. horses was the pq db? This is an open-edit db and when I checked those names not all of them were locked. I hope they were showing the color as per the stud book record when checked for this study. (How hard can it be to pick up the 'phone and call Weatherby's?)

[aethervox]

Accurate Determination of Phenotypic Information from Historic Thoroughbred Horses by Single Base Extension - http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0015172

I did have to e-mail the first author on the last paper, though, because he states that the cream gene doesn't exist in the Thoroughbred. I await his response!

Please let us know what he has to say. I checked the 2003 report by Mariat et al. re. mapping the cream gene. It makes no such statement.

Fwiw - I suspect this project was born from the need to discriminate between samples, all alleged to be from the remains of Eclipse, but which proved to have come from two or more different horses. Using coat color for this purpose carries a high risk of false positive identification, but it may have been the only viable option.

Did you notice that their source for the coat color of the 13 subj. horses was the pq db? This is an open-edit db and when I checked those names not all of them were locked. I hope they were showing the color as per the stud book record when checked for this study. (How hard can it be to pick up the 'phone and call Weatherby's?)

Yes I noticed that they used PQ as a source, and I wondered about that as well.

I think the project was a by-product of the study they did on mtDNA. The reference they give for the rationale of choosing those horses --because they already knew they could get viable mtDNA from them -- is Bower MA, Campana MG, Nisbet RER, Weller R, Whitten M, Edwards CJ, Stock F, Barrett E, O'Connell TC, Hill EW, Wilson AM, Howe CJ, Barker G, Binns M (Submitted) Truth in the bones: science resolves the identity of Thoroughbred racehorse sires.

I remember there being controversy about Bend Or's dam; was there also controversy about Eclipse as well?