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Lethal White Syndrome

Sport Horse Breeding
#21

[QUOTE=JB;6846105]
No, there is absolutely no excuse. None. Ignorance abounds though, well, it’s worse than ignorance because you can fix that by education, but you can’t fix stupid.

There are still Paint breeders who INSIST, despite the very simple concept of the Punnet Square, they have a better chance of a colored Frame foal if the breed nO to nO.

There is ONLY a 50% chance of a live (nO) foal no matter if you breed nn x nO, or nO x nO.

The nO x nO breeding gives you a 25% chance of nn, and 25% chance of OO - lethal, where nn x nO gives you the other 50% as nn.

The stupid Paint breeders still tell you the 25% chance is not right, and that it’s really lower than that :rolleyes: :no:

Anyone breeding anything ought to be required to pass a basic competency test on lethal breeding situations, which goes beyond Lethal White. There are other breeds with other lethal consequences, and there are other breeds besides Paints that have LWO issues, including TBs (though just a very few lines).

that test ought to include knowing or learning that an absolutely 100% solid horse not a single white hair, can be a Frame carrier.

So no, there is no excuse.[/QUOTE]

There was an epic thread on another horse bulletin board a few years ago that demonstrated this exact line of thinking. Woman bred two known carriers and got a lethal white foal. First she spent a lot of time denying that the foal was lethal white and then she did some amazing math gymnastics to prove that the chances of a lethal white were less than 25%. So JB, I might not have believed your post except I watched the whole train wreck and yep, it’s true. That’s exactly what they think.

I’m a biology major and it boggles my mind! :confused::rolleyes::sadsmile:

#22

[QUOTE=Laurierace;6845863]
This person said something along the lines of she didn’t get her papers until after she bred her. People are offering their condolences while I was looking for torches and pitchforks.[/QUOTE]

And I am sure they are also praying fervently… sigh … MS… I only watch two farms… and never get on the main board…

#23

[QUOTE=JB;6846164]
It’s not in the gene pool of other breeds - it didn’t jump ship :slight_smile: It’s on the gene pool of mixed breeds.

If the AQHA had put a stop to registering ?H horses when the test became available in 1992, it would not be NEARLY the issue it is now. But, it would still be around, because it was 17 years between Impressive being born and the disease even identified, which meant at least 12 years of people breeding to him, then to his nH sons, breeding his nH daughters, in/line breed to create the HH horses, and by then it’s just too late :([/QUOTE]

Sorry JB, It is in other breed Registries. Better? :wink:

#24

The really sad part is there are so many of these traits HERDA, GBED, EPSM, and MH besides the ones that have already been mentioned. I understand that every registry has issue, but there is tests for most or all of this conditions. I really don’t get why the registries with these issue keep allowing horse to breed who have clear genetic defects. Especially when these test are so cheap It’s not fair owners or horses.

#25

fwiw, i have read the reason why AQHA still allows breeding of carrier horses is because if you don’t it limits the gene pool too much.

If you have a genetic test, then you can test your horses and breed a carrier to a non carrier and you wont get an affected horse altho it will have a 25% chance of being a carrier.

i know this because right now the Connemara breed is going thru something similar - the Connemara has a genetic disease called Hoof Wall Separation Syndrome - HWSS - and while we dont have a genetic test yet (maybe late summer) Connemara breeders have been told to continue breeding their carriers to non carriers so important genetic material isnt lost.

there are many papers about this subject that will inform folks as to why it is important to continue to breed the carrier but only to non carriers.

For some reason it seems that the genetic diseases tend to accompany really fantastic breed qualities - in the Connemara many of the HWSS ponies are lovely ponies with fantastic type and super athletic ability. I wont name names but some of the most well known athletic ponies are carriers.

#26

[QUOTE=FayeHanoverian;6846217]
The really sad part is there are so many of these traits HERDA, GBED, EPSM, and MH besides the ones that have already been mentioned. I understand that every registry has issue, but there is tests for most or all of this conditions. I really don’t get why the registries with these issue keep allowing horse to breed who have clear genetic defects. Especially when these test are so cheap It’s not fair owners or horses.[/QUOTE]

Consider that many of these traits are recessives - so as long as you test everyone and breed responsibly - the fact that a horse is a carrier is really not a big deal. Carriers can be excellent individuals with many other positive traits, so why remove them from the gene pool?

Now, dominant traits, like HYPP, I think need to be handled differently. Hindsight is 20/20, but they shouldn’t have allowed the N/H and H/H horses to breed on. What made it worse was the folklore? truth? that HYPP resulted in those big muscles that halter folks liked, and once that caught on, the horse was out of the barn so to speak on HYPP. Breeders are apparently willing to take the risk to get what they want. The one horse with HYPP that I observed first hand was a really pretty guy and I guess no one cared too much about having to send some of his offspring to the killers (not that I agreed, but not my business!). Darn shame that he died of an HYPP attack, but again, I guess they were willing to take the risk. As I said above, not a pretty picture.

#27

no excuse.

You know those ppl that you dislike, and everything you learn about them only demonstrates that your dislike is well founded?

Well, I found out that woman that travels in my horsie circles bred a lethal white. And wha wha wha she was so devastated. Amateur hour all around, she had no business breeding horses.

#28

I agree there is no excuse. I have a breeding stock APHA mare (sire was overo) who has 3 socks and a blaze and does not look overo. But just in case she was a minimal I had her tested (as well as for HYPP) and she was negative for both. To me there is no excuse and I feel terrible for the foal that had to suffer from her ignorance :frowning:

#29

[QUOTE=mbm;6846246]
fwiw, i have read the reason why AQHA still allows breeding of carrier horses is because if you don’t it limits the gene pool too much.

If you have a genetic test, then you can test your horses and breed a carrier to a non carrier and you wont get an affected horse altho it will have a 25% chance of being a carrier.

i know this because right now the Connemara breed is going thru something similar - the Connemara has a genetic disease called Hoof Wall Separation Syndrome - HWSS - and while we dont have a genetic test yet (maybe late summer) Connemara breeders have been told to continue breeding their carriers to non carriers so important genetic material isnt lost.

there are many papers about this subject that will inform folks as to why it is important to continue to breed the carrier but only to non carriers.

For some reason it seems that the genetic diseases tend to accompany really fantastic breed qualities - in the Connemara many of the HWSS ponies are lovely ponies with fantastic type and super athletic ability. I wont name names but some of the most well known athletic ponies are carriers.[/QUOTE]

HYPP traces back to a genetic mutation in ONE horse “Impressive” (how ironic is that?) So, breeding affected horses to keep from “limiting the gene pool” really isn’t a legitimate argument. I would like to see those papers and by whom they are written. Surely not by anyone who has a financial stake in the matter?:cool:

mbm , N/H horses are not “carriers”, they have the disease and many of them die from it… So the 25% chance you cite is the chance of producing a horse with HYPP, the disease, not a “carrier”.

HYPP is an autosomal DOMINANT disorder. Certainly you can breed H/N horse to an N/N horse and have a CHANCE of producing an unaffected foal, but WHY would anyone do that? It is irresponsible IMHO. Same with Lethal White, it can be eliminated if people educate themselves and/or give a damn.

Lethal white is a more immediate death, HYPP is sometimes"manageable", sometimes not, resulting in the death of the horse. There is no excuse for either of these conditions to occur in this day and age. Period.

#30

[QUOTE=Laurierace;6845863]
This person said something along the lines of she didn’t get her papers until after she bred her. People are offering their condolences while I was looking for torches and pitchforks.[/QUOTE]
She knew, and has since said as much. She’s bred this mare at least twice before and decided to take the chance this time and lost.
From here

Yes Cindy, i am not going to lie, pocket has thrown a solid the last 2 years I tried something different and paid the price, it is something I will never do again in this lifetime

She’s a POS unethical breeder and has absolutely no business breeding

#31

[QUOTE=skydy;6846192]
Sorry JB, It is in other breed Registries. Better? ;)[/QUOTE]
Yes :smiley:

However, even then, it IS in other breeds, though it didn’t jump there from the Paint. It’s in the TBs, though just a very few lines.

#32

[QUOTE=FayeHanoverian;6846217]
The really sad part is there are so many of these traits HERDA, GBED, EPSM, and MH besides the ones that have already been mentioned. I understand that every registry has issue, but there is tests for most or all of this conditions. I really don’t get why the registries with these issue keep allowing horse to breed who have clear genetic defects. Especially when these test are so cheap It’s not fair owners or horses.[/QUOTE]
One needs to be very, very clear in delineating these diseases between those that cause health problems even in the heterogyzous form, and those that cause problems only in the homozygous form.

There’s no need to eliminate Frame simply because it’s homozygous Lethal. The nO horse is perfectly healthy, and brings the desired color pattern a good bit of the time.

HERDA is just fine in the hetero state as well - just don’t breed to another HERDA horse.

HYPP? Bad news even in the hetero form, and should and CAN be eliminated - can be eliminated in just 1 generation.

#33

P-poor reason, if that is one, because of the vast number of limes that DON’T have HYPP

No, the real reason is $$ and politics :frowning:

If you have a genetic test, then you can test your horses and breed a carrier to a non carrier and you wont get an affected horse altho it will have a 25% chance of being a carrier.

Yep, and still have a decent chance of producing the color which is coveted by Paint breeders, all without any risk of the LWO foal :slight_smile:

i know this because right now the Connemara breed is going thru something similar - the Connemara has a genetic disease called Hoof Wall Separation Syndrome - HWSS - and while we dont have a genetic test yet (maybe late summer) Connemara breeders have been told to continue breeding their carriers to non carriers so important genetic material isnt lost.

I had no idea they had that - will have to read up on that :slight_smile: The Connies are a much MUCH smaller breed than QH’s/Paints.

Is WSS something that is apparent very early on? Is it a problem only when homozygous? I’m assuming so based on the other stuff you’ve said

For some reason it seems that the genetic diseases tend to accompany really fantastic breed qualities - in the Connemara many of the HWSS ponies are lovely ponies with fantastic type and super athletic ability. I wont name names but some of the most well known athletic ponies are carriers.

But aren’t many Connies in general, fantastic? :slight_smile: I get what you’re saying. It will be interesting to see if, down the road, this is linked to another gene that brings “good things” to an individual, which would make the homozygous ones that much better. But usually what happens is a gene like this gets to an animal that also has something else, and it’s the something else that’s bred for, bringing with it, unknowingly, the defect :frowning:

#34

[QUOTE=Laurierace;6845887]
Somebody is keeping the mods busy over there so it must not just be me who is disgusted. I am a cam owner there otherwise I would risk being banned.

Here is part of the post. It sounds as if they did test and therefore knew this was likely.
when I bought pocket I lost her papers , by th time I got her papers and sent off to have her tested I had already bred her[/QUOTE]

No, Laurie you are definitely not the only one who was disgusted by this mess. I would have had some scathing remarks as well, but am in the same boat as you and can’t afford to be banned either.

NO EXCUSE!:mad:

#35

[QUOTE=FalseImpression;6846176]
And I am sure they are also praying fervently… sigh … MS… I only watch two farms… and never get on the main board…[/QUOTE]

The foal is long dead so the prayers are for the mare and her owner.

#36

here is one link to the info i was talking ab out re: genetic diversity.

http://www.papillonclub.org/PapillonHealth/ARTICLES/094-Practical-Genetic-Counseling.html

also, my comments were not about dominant genes but about recessive ones… folks were saying that no carrier should be allowed to breed - i am saying yes, they should - but only to a non carrier animal. I believe right now many people are still breeding PB Connemara ponies to other PB ponies even knowing that HWSS may be the result… so it isnt just in QH’s that this happens. In lieu of a test there are breeders that know which of their ponies are carriers and have eliminated HWSS in their breeding - but a test sure would help! And hopefully the Connemara registries will require test status on all papers esp for breeding animals… but there are still folks that refuse to admit it is a real genetic disease…

as for HWSS - just do a google search. the info is out there…

and as the observation that carrier ponies are usually super ponies - it is true - so there must be some link between the genes that produce those certain traits and the genes that cause HWSS. I know the ponies I know that have it are the nicest ponies I know.

#37

if you are not breeding for color–when should you be alert to this? My head hurts from the terminology and I otherwise dont care about color.

We are breeding to a wb stallion that has occassionally bred some wildly marked with white foals and the mare- bay -appears to have a “skunk” tail white socks on legs and her chestnut mother had white socks and blaze and white through coat. I am so confused as to the terms being used and when you would be alerted to the possibility of the overo gene being present in one or both parents.

#38

[QUOTE=JB;6846580]
Yes :smiley:

It’s in the TBs, though just a very few lines.[/QUOTE]

It’s my understanding that HYPP only occurs in QH and QH crosses, specifically in horses that trace back to Impressive. Impressive had a high percentage of TB blood (line-bred Three Bars IIRC), but apparently the mutation first occurred in him, not his TB predecessors. Are there any research studies that verify that it also occurs in TBs?

#39

Genetic diversity is much more of a problem with pure, closed breeds. The QH is not closed, as they allow TBs, and when you have the combination of hundreds of thousands of each, diversity is not an issue LOL

also, my comments were not about dominant genes but about recessive ones… folks were saying that no carrier should be allowed to breed - i am saying yes, they should - but only to a non carrier animal.

ENTIRELY depends on the effect of the gene. Carriers of HYPP should never be allowed to breed, because nH IS having the disease, not merely a carrier. But HERDA carriers are unaffected in the hetero state, and sure, there can be an argument to allow them to breed to non-carriers, but still - why? In this case, it’s a QH thing, diversity is not an issue, why not disallow registration of all carriers and just get rid of the disease? well, “get rid of” as best we can, as there will always be unregistred crossbred carriers :frowning: There isn’t any benefit, aesthetic or otherwise, to allow carriers to remain around, not like Frame/LWO

I believe right now many people are still breeding PB Connemara ponies to other PB ponies even knowing that HWSS may be the result… so it isnt just in QH’s that this happens. In lieu of a test there are breeders that know which of their ponies are carriers and have eliminated HWSS in their breeding - but a test sure would help! And hopefully the Connemara registries will require test status on all papers esp for breeding animals… but there are still folks that refuse to admit it is a real genetic disease…

as for HWSS - just do a google search. the info is out there…

and as the observation that carrier ponies are usually super ponies - it is true - so there must be some link between the genes that produce those certain traits and the genes that cause HWSS. I know the ponies I know that have it are the nicest ponies I know.

No disagreement here :slight_smile: It will be interesting to know in the future if the link is actually genetic, or if it’s a man-made issue by choosing one trait and inadvertently bring along the WSS. If it’s the latter, it can be bred out while retaining the quality characteristics.

#40

If you’re in a breed where Frame just isn’t there, it’s not a worry :slight_smile:

We are breeding to a wb stallion that has occassionally bred some wildly marked with white foals and the mare- bay -appears to have a “skunk” tail white socks on legs and her chestnut mother had white socks and blaze and white through coat. I am so confused as to the terms being used and when you would be alerted to the possibility of the overo gene being present in one or both parents.

The confusing part is really from folks who insist on using Overo when they really mean Frame. Overo is everything not-Tobiano, and Frame is just one of the Overo patterns. You still have Sabino, Splash, and Dominant White as Overo patterns/gentics, and none of them have this issue. The only health issues there are some Splash horses are deaf (nearly always, maybe only always, in the homozygous state) and Dominant White (of which there are MANY mutations, 12 testable ones, many more new ones) is strongly thought to be embryonic lethal, so it’s a pregnancy that “didn’t take”.

I don’t know of any WB stallion who is Frame. None of the color patterns you list match the look of Frame, but if you want to name the lines, I or someone can help you determine if Frame is remotely in the picture. The odds are greatly that it’s not :slight_smile:

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