Buckpasser in the X

[stancaris]

Pan Zareta wrote: "That's not what I "believe". Thats what the available genome- based evidence indicates". Thats just your opinion not fact. The fact that genomic research has found only a few variants on the X that relate to elite performance does not prove that the X is of minor value in this regard. Just because they found many more variants on other chromosomes also just stands to reason because there is only one X but there are 31 autosomes.

Then you go on to say you have no beliefs, opinions, or biases. Let me first say that you are highly opinionated and have consistently had the strong opinion that the X chromosome is of minor importance at best to broodmare sire success and you are deluded into thinking that genomic evidence proves this. That's nonsense.

There are variants on the X that relate to elite performance and one of them reached statistical significance. That statement alone by Byron Rogers indicates that the X is more than a minor role player in broodmare sire success. Why can't we find out what that variant is? Is it a a secret known only to Rogers company?


I have presented many sources of statistical data that support the idea of the importance of the X chromosome in broodmare sire success. You continually toss them out as meaningless because they do not fit into your basic tenent that the X at best is only of minor importance in this regard.

Just because the evidence I presented is circumstantial does not make it unreliable. Many theories thru time have been based on circumstantial evidence (Evolution is one example).

Isn't it overwhelming that 42% of the top 10 broodmare sires over the last five years carry either Secretariat or Buckpasser as their broodmare sire or second damsire. Secretariat and Buckpasser have enormous influences on the American thoroughbred today and they are found consistently close up in the X passing position of 42% of the top ten broodmare sires. Both Secretariat and Buckpasser are reknown broodmare sires and they transmit 100% of their X chromosome to all their daughters.

Its not just by chance that two of the greatest broodmare sires in recent times, Buckpasser and Secretariat are found in the X passing position of 42% of the top 10 leading broodmare sires over the last 5 years. These two broodmare sire greats are purposely being selected in that position by owners and breeders of thoroughbreds. Their X chromosomes are important in that success.

[DDT]

Stan

Darwin just flipped over in his grave.

DDT

[Pan Zareta]

Pan Zareta wrote: "That's not what I "believe". Thats what the available genome- based evidence indicates". Thats just your opinion not fact.

How could you possibly differentiate between fact and opinion in regard to genome-based evidence for TB performance? It's obvious that you're completely unfamiliar with any of it beyond what was provided to you in 'The Mares in Great Sires' thread. You claim that information is untrustworthy due to commercial bias. That's pretty hypocritical given the facts that not only do you have no way of objectively judging whether it is or not but you also have a strong commercial stake of your own in circumstance-based claims that the X is far more influential to broodmare sire success than that information indicates (ref. pps. 49-50 of your Analyzing the Triple Crown, available in hard copy for $39.95).

No one is denying that there are variants on the X that are of some minor relevance to broodmare sire success. There's little room for reasonable dispute if you want to speculate that those variants were of some help to Buckpasser, Secretariat, et al. becoming excellent broodmare sires. However, that doesn't justify attributing their excellence in any large part to the X and you really need to accept the obvious, that they would probably never have been able to become excellent broodmare sires had the more important non-X genetic variants and most environmental factors not first been strongly in their favor.

[DDT]

Stan

Environmental influence plays a large part in broodmare sire success. Since 1935 all leaders of the North American broodmare sire list stood at stud in Kentucky except for Northern Dancer in 1991, Sadlers Wells in 2008, 2009 and 2010, and Danehill in 2011 and 43 of them stood at Claiborne Farm including Buckpasser, Secretariat and Mr. Prospector. All of these stallions not only had access to quality mares, a large number of foals from their daughters received the best of care and opportunity to grow at Claiborne.

DDT

[stancaris]

There are many genes on the X chromosome whose function is known. On the internet under the title Genetics Home Reference X Chromosome one finds genes that function as follows:

DMD- a gene on the X chromosome that strengthens muscle fibers in the skeleton and heart.

FGD1- a gene on the X chromosome that forms the skeleton.

HCCS- a gene on the X chromosome that produces holocytochrome C which is related to the production of ATP an important energy source in horses.

MTM1- a gene on the X chromosome that develops and maintains muscle cells.

PGK1- another gene on the X that is important in the formation of ATP

PHEX another gene on the X that causes growth of bones and is important in strengthening bones.

GATA1- a gene on the X chromosome that regulates the activity of many other genes.

IKBKG- another gene on the X chromosome that controls the activity of other genes.

MED12- a gene on the X chromosome called the mediator complex subunit 12 links transcription factors which are proteins that influence whether genes are turned on or turned off.

The last group of genes seems very significant as to the function of the X chromosome. Their presence is important as a turn on-turn off mechanism for other genes and therefore may play a vital role in imprinting etc.

The above are just some of the genes listed on that site that support the idea that the X chromosome plays more than just a minor role in broodmare sire success.

[Pan Zareta]

The above are just some of the genes listed on that site that support the idea that the X chromosome plays more than just a minor role in broodmare sire success.

The reference basis at that site is the human genome. The gene order on the human X and the equine X are highly though not completely conserved but what matters in the current context is not which genes are on the X but the variability, if any, that exists within them or in the code around and between them and whether or not any of those variables are relevant to TB performance. Long stretches of code in every species are exactly alike. Where there is no variability, there is no performance advantage/disadvantage. Listing the genes that are on the human X and may be in roughly the same location on the equine X doesn't prove there are any relevant variables within or around/between them. That's what SNP chips were designed to do, and have done.

[stancaris]

Pan Zareta: You said where there is no variability there is no performance advantage and that the SNP research's main objective was to find variants and that research has done just that. So are the variants discovered by genomic researchers the be all- end all of all that a horse becomes.

Are you therefore of the opinion that Buckpasser's X chromosome and Secretariat's X chromosome which they transmitted to all their daughters carried no variability and therefore had no performance advantage when inherited by their daughters. Are you of the opinion that Busanda's X and Somethingroyal's X carried just ordinary genes and when they gave those Xs to Buckpasser and Secretariat those Xs just played a minor role at best in regarding their broodmare sire success?

I guess your view is that genomic research proves that Busanda's X and Somethingroyal's X were just run of the mill Xs and had little or no influence as to why Buckpasser and Secretariat became great broodmare sires.

Would you also be of the opinion that Buckpasser's X chromosome would be no more advantage to his daughters than an X from any other run of the mill horse?

So basically are you relegating the X of Busanda and Somethingroyal to minor influence at best in regards to Buckpasser and Secretariat's great influence today in modern horses?

[Pan Zareta]

Pan Zareta: You said where there is no variability....

Don't try to "guess" what my "view" is (on any subject) or expect reply to your tedious interrogatory loaded with false presuppositions about same, many of which are in direct contradition of statements para 2, my first post this page.

[DDT]

Stan

Are you suggesting that any other run of the mill horse would compile the same great broodmare sire records as Buckpasser if that run of the mill horse received the same X chromosome from Busanda?

DDT

[Jeff]

http://www.pedigreequery.com/san+telmo3

[stancaris]

What I am suggesting and have always stood by is the following:

Buckpasser received his X chromosome from the superior mare, Busanda and transmitted that X to all his daughters. I believe that X chromosome from Busanda was instrumental in making Buckpasser a great broodmare sire. I do not believe as Pan Zareta has repeatedly stated that Buckpasser's X only played a minor role at best toward Buckpasser's success as a broodmare sire. Furthermore, I believe Busanda's X was not just an ordinary X chromosome. It probably carried superlative genes that had an influence on Buckpasser's great record as a broodmare sire and an AEI of 3.23 cumulative as of 2002.

Side note: Another interesting tidbit along these lines is the fact that since 1989 there have been 7 Kentucky Broodmare's of the Year that carried Buckpasser in their X passing position. They are:

1989 Broodmare of the Year-Relaxing whose sire was Buckpasser
1991 Broodmare of the Year-Toll Booth whose sire was Buckpasser
1992 Broodmare of the Year-Weekend Surprise whose Broodmare sire was Buckpasser

1996 Broodmare of the Year-Personal Ensign (Buckpasser is the Broodmare sire of Personal Ensign's sire, Private Account

2002 Broodmare of the Year- Tousasaud (Buckpasser is the Broodmare sire of her sire, El Gran Senor

2010 Broodmare of the Year- Liable ( Buckpasser is the Broodmare sire of her sire, Seeking the Gold

2011 Broodmare of the Year-Oatsee (Her sire, Unbridled, is among the leading broodmare sires today and Unbridled carries Buckpasser in the X passing position by way of his dam Gana Facil, her dam Charedi and her dam Magic, a daughter of Buckpasser

Those powerful conduits of Buckpasser's X chromosome have a widespread influence and for the most part close up in the pedigrees of the above broodmares of the year with the exception of Unbridled who has Buckpasser in his fifth generation

[DDT]

Stan

You have ignored answering my question.

Of note, all of the superior performers that provided the reason those Kentucky Broodmares of the Year status to be considered for the award were sired by highly ranked stallions, I guess their input to the offspring does not matter or did not provide important and significant genes to these runners.

And, while you are on today here is another question for you Stan, do you actually believe that evolution is a theory and not a scientific fact?

DDT

[Pan Zareta]

Stan, how many mares were bred to Buckpasser that themselves had been or would become Broodmares of the Year?

There were at least 5 and none were dependent on the record of their progeny by Buckpasser to achieve that distinction. Is your X factor tunnel vision so severe that you can't even begin to comprehend the import of that in regard to his broodmare sire success? What percentage of Kentucky stallions of Buckpasser's era covered that many Broodmares of the Year?

[stancaris]

Pan Zareta: Do you only see Busanda's X chromosome in Buckpasser playing a minor role in Buckpasser's success as a broodmare sire? Is your tunnel vision so severe toward relegating the X chromosome to being of only slight importance that you cannot even begin to comprehend the importance of the X chromosome of that superior mare, Busanda, as a conduit of genes on Buckpasser's X chromosome that were important in placing him among the great broodmare sires?

[Pan Zareta]

Pan Zareta: Do you only see Busanda's X chromosome in Buckpasser playing a minor role in Buckpasser's success as a broodmare sire?

Yes. It's what the direct and most credible evidence indicates and I have no conflicting interests making me reluctant to acknowledge that some of Busanda's other chromosomes had more influence than the X on Buckpasser's success on the turf and in the stud.