The Colors of Life

You are here

Splash To Splash??

103 posts / 0 new
Last post
Sara
Sara's picture
Offline
Last seen: 9 years 4 months ago
Joined: 02/13/09
Re: Splash To Splash??

Count me as one who is convinced splash is incomplete dominant. I don't think it's *always* easy to tell the homozygous animals visually though since white expression may be boosted or suppressed by something else that is going on.

I believe it was Maigray who said Cory is between what is considered typically homozygous and typically heterozygous as far as his markings go. We'll know more through more breeding but so far three of three foals have evidence of splash.

[url=http://www.myrewyn.com/]Myrewyn Equestrian[/url]

[url=http://myrewyn.com/sales/]New! Updated sales list.[/url]

tjuri
tjuri's picture
Offline
Last seen: 5 years 10 months ago
Joined: 07/12/09
Re: Splash To Splash??

Has there been any article published or any theories where the Splash gene might be located? Can you rule out KIT as a possibility? :roll:

So far I get the impression that every white pattern which might cause any roaning is located on KIT, so maybe Rabicano as well? :bounce

horsegen
horsegen's picture
Offline
Last seen: 8 years 1 week ago
Joined: 03/10/09
Re: Splash To Splash??

No articles published, but a couple of mapping studies have been done. Splash does NOT appear to be caused by KIT...everyone looked at that region extensively. There have been one or two candidate genes tentatively identified, but the mapping is often inconclusive due to the difficulties in correctly phenotyping these animals, and no mutations have been found.

tjuri
tjuri's picture
Offline
Last seen: 5 years 10 months ago
Joined: 07/12/09
Re: Splash To Splash??

Thanks for the fast reply concerning Splash! :flower

I will ask the roan question on a roan thread... :D

NZ Appaloosas
NZ Appaloosas's picture
Offline
Last seen: 6 years 7 months ago
Joined: 02/14/09
Re: Splash To Splash??

So does LPlp. Leopards can apparently be near leopards to full leopards. Blankets can have huge blankets or a small blanket. Other patterns can also make horses look like false few spots and false snow caps. Does that mean its not incomplete dominant because if it was, there shouldn't be a way for a horse to look like its h

LPlp White expression has nothing to do with LP. PATN controls how much white a leopard has. LP only turns on the spots.

Yes, but what I am trying to say is that a horse who is genetically supposed to look like a leopard or a blanket CAN look like a false snow cap or a false few spot.

I've a head cold and lost the attributes so have left the one I know is there.

The thing is, RMT, the false snowcap/fewspot is the result of another white gene(s) interacting with Lp, shrinking and/or erasing spots, thus creating the illusion of a "solid white", which has nothing to do with any sort of dominance, other than "dominance" over Lp, not over white expression. I hope that makes sense...it's 73 and I'm shivering so I think I'm running a higher than wanted temp

Diane

NZ Appaloosas
NZ Appaloosas's picture
Offline
Last seen: 6 years 7 months ago
Joined: 02/14/09
Re: Splash To Splash??

Count me as one who is convinced splash is incomplete dominant. I don't think it's *always* easy to tell the homozygous animals visually though since white expression may be boosted or suppressed by something else that is going on.

I believe it was Maigray who said Cory is between what is considered typically homozygous and typically heterozygous as far as his markings go. We'll know more through more breeding but so far three of three foals have evidence of splash.

I'm not saying it isn't, I am saying that there is too much variable in the expression to state categorically that XYZ is HZ and ABC is hz. As one of our goals with the website and forum is to be as scientifically correct as possible, I think we need to avoid pitfalls like that.

Diane

Sara
Sara's picture
Offline
Last seen: 9 years 4 months ago
Joined: 02/13/09
Re: Splash To Splash??

As one of our goals with the website and forum is to be as scientifically correct as possible, I think we need to avoid pitfalls like that.

Oh, so have LP and PATN been scientifically proven now?

[url=http://www.myrewyn.com/]Myrewyn Equestrian[/url]

[url=http://myrewyn.com/sales/]New! Updated sales list.[/url]

RiddleMeThis
RiddleMeThis's picture
Offline
Last seen: 4 years 9 months ago
Joined: 03/08/09
Re: Splash To Splash??

I'm not saying it isn't, I am saying that there is too much variable in the expression to state categorically that XYZ is HZ and ABC is hz.

Every single white patterning genes (including the incomplete dominants) have HUGE variations of expression. It's not the expression that is cluing us in on Splash being incomplete dominant but the breeding patterns. What the loud splash produce. What the minimals produce, and what they produce together. THAT is the evidence. NOT the expression.

IMAGE(http://alterna-tickers.com/tickers/generated_tickers/i/ikmc9z103.png)

accphotography
accphotography's picture
Offline
Last seen: 4 years 10 months ago
Joined: 02/15/09
Re: Splash To Splash??

Well being scientifically correct and avoiding pitfalls is one thing, but there is nothing wrong with creating and backing theories. Scientific research can't be done if theories aren't put out there. I'd like to think we can be part of the research by coming up with the theories that will have a huge impact on the future.

IMAGE(http://i173.photobucket.com/albums/w65/accphotography/Misc/Sig.png) IMAGE(http://phrf.pitapata.com/uno2m5.png)

rabbitsfizz
rabbitsfizz's picture
Offline
Last seen: 4 years 9 months ago
Joined: 02/16/09
Re: Splash To Splash??
As one of our goals with the website and forum is to be as scientifically correct as possible, I think we need to avoid pitfalls like that.

Oh, so have LP and PATN been scientifically proven now?

No.
Absolutely NOTHING about the Appy pattern has been proven.
It is all, even after all these years, still conjecture pure and simple.
And I become more and more concerned, as people bandy these terms around as if they were fact (on other forums, it really does not matter here too much) that the "facts" will be bent to fit the conjecture.
I am even beginning to suspect a conspiracy theory, because the fact don't fit!!! :sign
It just seems very strange to me, that people can hold forth about LP and PATN and still have NO proof whatsoever......

website: please come and visit... http://www.shadowplayminihorses.co.uk/

nerd
nerd's picture
Offline
Last seen: 7 years 7 months ago
Joined: 03/10/09
Re: Splash To Splash??

Every single white patterning genes (including the incomplete dominants) have HUGE variations of expression.

I kinda disagree with this statement. Yes, there are variations in expression. However, I would argue that among the genes we understand that DO show incomplete dominance, it is fairly straightforward to tell based on expression which individuals are homozygous and which are heterozygous. In terms of white patterning genes that we know about and can test for, there are basically frame, where the difference is a clear matter of life/death as well as coat pattern; SB-1, where it's a matter of all-white vs. loud white; and tobiano, where there are often the paw prints/ink spots that associate with homozygous individuals.
Splash, in contrast, is not fully understood--there is no test, and we can't systematically identify homozygous vs. heterozygous individuals, so I think it's a bit absurd to talk about characteristics of incomplete dominance/expression. In addition, there is probably a whole lot of overlap between what we think heterozygous splash looks like and what all the not-understood "sabino"-clusterf*ck gene(s) cause. I believe that the reason our community sees such an apparently huge variation in the expression of splash is primarily because we don't fully understand what it is and what should and should not be called splash.

It's not the expression that is cluing us in on Splash being incomplete dominant but the breeding patterns. What the loud splash produce. What the minimals produce, and what they produce together. THAT is the evidence. NOT the expression.

Now this, I completely agree with--this SHOULD be our approach to understanding splash. From what I understand, certain families certainly show trends of expression associated with being homozygous vs. heterozygous based on pedigree, and I wish that someone would go ahead and put some material up on the interwebs studying this, analyzing it, and getting the numbers and pictures out there for the sake of comparison. Takers?

AppyLady
AppyLady's picture
Offline
Last seen: 7 years 4 months ago
Joined: 06/16/09
Re: Splash To Splash??

Absolutely NOTHING about the Appy pattern has been proven.
It is all, even after all these years, still conjecture pure and simple.
And I become more and more concerned, as people bandy these terms around as if they were fact (on other forums, it really does not matter here too much) that the "facts" will be bent to fit the conjecture.
I am even beginning to suspect a conspiracy theory, because the fact don't fit!!! :sign
It just seems very strange to me, that people can hold forth about LP and PATN and still have NO proof whatsoever......

Actually, that's not true. The Lp gene has been located, and PATN1 has been narrowed to a certain location. PATN1 is NOT in the same area as LP, which means they are inherited separately, and one can be inherited without the other.

Daylene Alford
Offline
Last seen: 1 month 1 week ago
Joined: 02/12/09
Re: Splash To Splash??

When was the LP gene located? I was under the impression that they had narrowed it down but hadn't been able to pinpoint it yet? Did something new happen recently?

Jenks
Jenks's picture
Offline
Last seen: 7 years 7 months ago
Joined: 02/21/09
Re: Splash To Splash??

When was the LP gene located? I was under the impression that they had narrowed it down but hadn't been able to pinpoint it yet? Did something new happen recently?

A few articles reference it's location on ECA1 - I don't know if that's exactly what you mean or not (with the "between" not being precisely clear on it being the only thing between or in the mass of stuff between the two)

From 2004: To refine the map position of LP, eight microsatellite markers on ECA1 (UM041, LEX77, 1CA41, TKY374, COR046, 1CA32, 1CA43, and TKY002) were analysed in the two half sib families. Results from this linkage analysis showed LP was located in the interval between ASB08 and 1CA43.

Several articles also state studies of Lp heterozygosity vs homozygosity with how they relate to the eye issues. But this is the most updated one, and I think they still have not narrowed it down - http://www.genetics.org/cgi/content/abst..." onclick="window.open(this.href);return false;

rabbitsfizz
rabbitsfizz's picture
Offline
Last seen: 4 years 9 months ago
Joined: 02/16/09
Re: Splash To Splash??

I rest my case.......

website: please come and visit... http://www.shadowplayminihorses.co.uk/

horsegen
horsegen's picture
Offline
Last seen: 8 years 1 week ago
Joined: 03/10/09
Re: Splash To Splash??

LP has been mapped to ECA1, and the gene causing LP is known. It is a gene called TRPM1, and researchers are convinced that it is causative of both LP and CSNB because they have done expression analysis of this gene. They looked at mRNA expression in both skin and eye samples of non-Appaloosa horses, heterozygous Appaloosas, and homozygous Appaloosas. Compared with non-Appaloosas, heterozygous Appys had very reduced expression of the TRPM1 gene, and the homozygous Appaloosas had virtually no expression of TRPM1. The researchers working on this gene have still not been able to find the exact mutation in/affecting TRPM1, but they have a couple of candidate mutations. A paper was just published on this:

Brief Funct Genomic Proteomic. 2010 Mar 29. [Epub ahead of print]

Fine-mapping and mutation analysis of TRPM1: a candidate gene for leopard complex (LP) spotting and congenital stationary night blindness in horses.

Bellone RR, Forsyth G, Leeb T, Archer S, Sigurdsson S, Imsland F, Mauceli E, Engensteiner M, Bailey E, Sandmeyer L, Grahn B, Lindblad-Toh K, Wade CM.

and PATN1 has been narrowed to a certain location. PATN1 is NOT in the same area as LP, which means they are inherited separately, and one can be inherited without the other.

Now, I have heard NOTHING about PATN1 being located. There have been no publications on this, so I can't substantiate it at all. Perhaps it's something that's been discussed on Appy boards, but I haven't heard a thing about it through the research grapevine.

RiddleMeThis
RiddleMeThis's picture
Offline
Last seen: 4 years 9 months ago
Joined: 03/08/09
Re: Splash To Splash??

SB-1, where it's a matter of all-white vs. loud white;

SB1 can be VERY minimal.
This is SB1sb1 and the white in the picture is the only white she has. IMAGE(http://www.mikarmafarm.com/memehead033003.jpg)

Now this, I completely agree with--this SHOULD be our approach to understanding splash. From what I understand, certain families certainly show trends of expression associated with being homozygous vs. heterozygous based on pedigree, and I wish that someone would go ahead and put some material up on the interwebs studying this, analyzing it, and getting the numbers and pictures out there for the sake of comparison. Takers?

I'll take. It will take me a while to get it all organized because there is so much there with different families, but I will attempt it for you.

IMAGE(http://alterna-tickers.com/tickers/generated_tickers/i/ikmc9z103.png)

Sara
Sara's picture
Offline
Last seen: 9 years 4 months ago
Joined: 02/13/09
Re: Splash To Splash??

RMT, if you do this, please use Vimpenny Sweet Sultan and his offspring as one of your families. There is so much splash in that group that I am fairly certain even some of the minimal ones are homozygous (or, what we think of as homozygous, sorry nerd!) In contrast, you can look at The Promise Welsh where they fairly frequently get loud splashes.

[url=http://www.myrewyn.com/]Myrewyn Equestrian[/url]

[url=http://myrewyn.com/sales/]New! Updated sales list.[/url]

RiddleMeThis
RiddleMeThis's picture
Offline
Last seen: 4 years 9 months ago
Joined: 03/08/09
Re: Splash To Splash??

The Promise Welsh is definitely on my list, and Ill add the family you have mentioned as well. There will also most likely be minis, some of the Gunner line, and then some random QH families who have cropped out splashes etc. Have to figure out how I'm going to get it all set up, if I am going to attempt a basic website (and possibly fail miserably with it) or just start organizing it and typing it out on Word and just posting it here.

IMAGE(http://alterna-tickers.com/tickers/generated_tickers/i/ikmc9z103.png)

nerd
nerd's picture
Offline
Last seen: 7 years 7 months ago
Joined: 03/10/09
Re: Splash To Splash??

Yay :D :D :D

Danni
Danni's picture
Offline
Last seen: 6 years 7 months ago
Joined: 02/13/09
Re: Splash To Splash??

This is SB1sb1 and the white in the picture is the only white she has. IMAGE(http://www.mikarmafarm.com/memehead033003.jpg)

Gosh that's a Sb1?! I always though it it as more of a roany pattern? Now I'd go out on a limb and say those face markings aren't Sb1, but the that the horse just happens to have those face markings from other sabino/splash and that the sb1 is so minimal that no roaning is present? Or maybe the horse has the odd white hair through the coat?

As far as PATN goes, I always had it in my head that all patterns needed some sort of white exressions genes to allow their patterns to show. Not just appy?

RiddleMeThis
RiddleMeThis's picture
Offline
Last seen: 4 years 9 months ago
Joined: 03/08/09
Re: Splash To Splash??

Yep, shes most definitely SB. Heres a full body photo of her
IMAGE(http://www.mikarmafarm.com/meme09-17-02goodweb.jpg)

These horses are also SB1sb1
IMAGE(http://www.mikarmafarm.com/rmstand2101604web.jpg)
IMAGE(http://www.mikarmafarm.com/lilylft070508web.jpg)
IMAGE(http://www.mikarmafarm.com/images/WFTraining123109FoxtrotWeb.jpg)
IMAGE(http://www.mikarmafarm.com/images/OutawLftLook051009web.jpg)

Possible SB1 positives
IMAGE(http://www.deervalleyfarmnewhampshire.com/images/rhythmsStar01.jpg)
IMAGE(http://www.deervalleyfarmnewhampshire.com/images/rhythmsShadow01.jpg)
IMAGE(http://www.deervalleyfarmnewhampshire.com/images/rhythmsRosebud01.jpg)
IMAGE(http://www.deervalleyfarmnewhampshire.com/images/rhythmsMelody01.jpg)

IMAGE(http://alterna-tickers.com/tickers/generated_tickers/i/ikmc9z103.png)

Hey What The
Offline
Last seen: 7 years 9 months ago
Joined: 03/21/10
Re: Splash To Splash??

I think I created a monster with this thread lol. Very informative but also very confusing :)

AppyLady
AppyLady's picture
Offline
Last seen: 7 years 4 months ago
Joined: 06/16/09
Re: Splash To Splash??

Right, Horsegen. I was in a hurry this morning and speaking in shorthand. Work is currently underway to sequence TRPM1 in order to isolate the LP mutation. I can't seem to find the email that indicated the general area of the PATN1 mutation. I'll keep looking. All I can find right now is a comment to the effect that you will not find any of their data or results anywhere, as they must both avoid pre-publishing themselves and protect their work.

It's interesting that some people on this forum dismiss all the research that's been done on Appaloosa genetics, and insist that it's nothing more than theory. And yet splash is accepted as if it were scientifically proven.

I remember when some people were absolutely certain that dominant white didn't exist. "There's no such thing as a white horse!" It's usually a good idea to keep an open mind.

accphotography
accphotography's picture
Offline
Last seen: 4 years 10 months ago
Joined: 02/15/09
Re: Splash To Splash??

RMT: I can help you put it into a website form if you want. Put the info in Word and I can put it into a simple website.

Danni: I truly believe there is a HUGE, HUGE, HUGE misconception with SB1. The majority of SB1sb1s I've seen look just like the ones RMT posted. Virtually every SB1SB1 I've seen is 100% white. I've not seen the roaning or the jagged phenotypes it supposedly produces. Except in TWH. I have a theory that the "SB1"s in TWH are ACTUALLY DWs. They fit the phenotype DEAD ON and they really don't fit the SB1 phenotype that any other breed shows. SB1 and DW would be very closely linked (possibly so close as to be virtually inseparable) and thus it could have been missed in the research IMO.

AppyLady: There still is no such thing as a white horse. :rofl

IMAGE(http://i173.photobucket.com/albums/w65/accphotography/Misc/Sig.png) IMAGE(http://phrf.pitapata.com/uno2m5.png)

AppyLady
AppyLady's picture
Offline
Last seen: 7 years 4 months ago
Joined: 06/16/09
Re: Splash To Splash??

ACC, if a horse is white, I'm going to call it white! :booty

accphotography
accphotography's picture
Offline
Last seen: 4 years 10 months ago
Joined: 02/15/09
Re: Splash To Splash??

I'm with ya completely. But I still have the argument on a near daily basis that if it's not another alelle on extension, it's not white, it's just a pattern.

IMAGE(http://i173.photobucket.com/albums/w65/accphotography/Misc/Sig.png) IMAGE(http://phrf.pitapata.com/uno2m5.png)

Fledgesflight
Offline
Last seen: 7 years 9 months ago
Joined: 02/12/09
Re: Splash To Splash??

Wow- all those SB1sb1 horses look so splashy. Does that first mare have blue eyes?

Fledgesflight
Offline
Last seen: 7 years 9 months ago
Joined: 02/12/09
Re: Splash To Splash??

I agree with ACC...the pattern is only white but the horse underneath is coloured.

RiddleMeThis
RiddleMeThis's picture
Offline
Last seen: 4 years 9 months ago
Joined: 03/08/09
Re: Splash To Splash??

Wow- all those SB1sb1 horses look so splashy. Does that first mare have blue eyes?

No, I am fairly certain the mares eyes are brown. I emailed them at one point and asked, and believe I was told that they are brown. I will have to look through my emails and see if I can find it.

ETA:Oh and this is SB1sb1 as well.
IMAGE(http://mofoxtrot.com/watson/images/snake.jpg)

IMAGE(http://alterna-tickers.com/tickers/generated_tickers/i/ikmc9z103.png)

Pages

pandemonium