Dam's Additional Influence on Racing Ability

[bobphilo]

This should be of interest to those that bet first time starters as well as those interested in racehorse breeding in general. It\'s the first hard scientific evidence of the added influence of the dam through her contribution of mitochondrial DNA. Sorry for the long post but I couldn\'t find a way to send it as a link to the article. The full text of the study is way too long to post, but anyone interested in reading it can e-mail me and I will send it to you. The point here is that this is why you should pay extra attention to the dam side of the breeding data.

Bob

\"New Take on What Makes a Winning Combination
By Greg Wood
March 22, 2006

A BRITISH scientist claims to have made a \"historic breakthrough\" in the study of thoroughbred genetics, after a six-year research project produced the first proof of a relationship between specific genes and the individual performances of racehorses.

The results of the study by Dr Stephen Harrison, whose company Thoroughbred Genetics is based in Kent, will be published next month in the peer-reviewed journal Mitochondrian.

It could have considerable implications for the bloodstock business, in which the winner of a classic — such as an English Derby — or a race such as the Golden Slipper can command a stud fee of tens, or even hundreds, of thousands of dollars, but in which young, untried horses often are bought for millions of dollars on little more than a hunch and a prayer.

Working with Juan Luiz Turrion-Gomez, Harrison studied eight \"athletically important\" genes in samples of mitochondrial DNA (mDNA) taken from 1000 racehorses, including classic winners. mDNA is significant because it is inherited solely from the dam side of a pedigree, while the mitochondria in which it is located are important cellular structures linked to energy release and respiration in muscles, and thus, according to Harrison, \"have a direct impact on the optimum performance of a racehorse\".

Harrison has discovered that different combinations of the performance-related genes will give horses different racing aptitudes, particularly with regard to optimum race distance, and the age at which they are likely to perform best.

His findings also could provide valuable information to trainers, who often adopt a \"try-it-and-see\" approach to finding a horse\'s best distance.

Thoroughbred Genetics now hopes to exploit its findings by offering a genetic testing service to breeders and owners who want to reduce as much of the risk as possible.

\"Breeding racehorses is a high-risk, multimillion-dollar industry,\" Harrison said this week. \"A high percentage of racehorse breeders fail to recoup their investments. Many foals produced are bred inappropriately and fetch poor prices at sales, a large proportion fail to reach the racecourse, and the vast majority never win a race ... The odds have for too long been stacked against the breeder, and the use of advanced genetic techniques to modernise traditionally based breeding programs can narrow down the quest to produce a truly brilliant horse. Racehorse breeding has effectively been fast-forwarded 200 years.\"

He hopes to lay to rest such beliefs as the idea that a stayer bred to a sprinter will necessarily produce a miler.

\"That\'s really like saying that if you take parts from a formula one car and mix them with bits from a tractor, you\'ll get a touring car in between,\" Harrison said. \"You are much better off co-ordinating all your efforts to try to make sure that you have the best genetic chance to start with.\"

The great Italian breeder Federico Tesio famously commented almost half a century ago that \"the thoroughbred racehorse exists because its selection has depended not on experts, technicians or zoologists, but one piece of wood: the winning post of the Epsom Derby\". Genetic science, it seems, may be about to prove otherwise.\"

[BitPlayer]

Bobphilo -

I looked at the original paper briefly (principally the abstract and some of the figures), but reading it with any care would require more time than I have these days.  Given the role of mitochondria in the cell, the idea that mtDNA inherited through the female line would be important to athletic performance seems unsurprising.  Some of the other claims in the journalist\'s summary strike me as a little more farfetched.

Have you read the original paper?  Do the statistical techniques they used seem appropriate?  Does the journalist\'s summary seem to reflect the paper or claims the authors may have made in interviews that weren\'t subject to peer review.

[bobphilo]

Bit,

I have the original paper as a pdf file but havn\'t read it in detail yet. It seems they\'ve isolated some genes on the mitochondrial DNA which are linked to increased ATP and energy production. The fact that the offspring get all their mitochondria from the dam is the main issue for handicappers in considering the relative role of the dam vs. the sire. Locating the genes and mDNA testing would be of great value for those about to spend big bucks on a yearling or 2YO.
As I said, I think it\'s too long to post but will glady send it to anyone interested. If anyone knows how I can send a long pdf file directly here, I can do that too. I\'ll read it in more detail and see if I can answer your questions.

Bob

[David57]

A related note, but not nearly as scientific. A book came out in the last year or two called Race Horse Breeding Theories that is a collection of articles by various authors. Rommy Faversham, who writes for the Thoroughbred Times, wrote a fascinating (at least to me) chapter about in-breeding to the female line, especially to certain foundation mares. He ran a number of analyses of mare in-breeding that produced a statistically significant increased number of stakes winners. It\'s not handy so I can\'t quote it, but I found the analysis pretty compelling. I used the method for choosing stallions for my mares this year, so in 2010 I\'ll let you know how well it worked.

[bobphilo]

The truest test of any study is that the same results can be replicated by other independent researchers. Even better is when it works in actual application.
I wish you the best of luck in your breeding program. Your strategy definitely incorporates the lastest scientific evidence. Please keep me (us) posted on your progress.

Bob

[miff]

There have been ongoing attempts for years to breed a \"super\" horse or to unlock some genetic secret. To date, it has failed miserably. Royally bred/expensive yearlings continue to go down the tubes,for the most part, year after year considering their cost vs accomplishments.

The most interest today is at the in training sales where they \"send\" the babies, like the Forestry colt (9.80sec. for an eighth) who brought $16 mill.Lets face it, if they can\'t run fast, does it really matter what the breeding is, except say for a mares value in the breeding shed.I have been lucky in beating many of these expensive type, royally bred horses, that can\'t outrun a fat man carrying a refrigerator on his back.

Look at the list of Derby winners and great horses of recent times and I do not believe there are too many that were \"royally\" bred.The new genetic thing pointed out by Bob will be interesting to follow as maybe this new science will unlock the secret to breeding the super horse.

[bobphilo]

What makes breeding and pedigree analysis so difficult is that there is no one\"super gene\" that makes a great horse. There are not just many genes involved but many combinations of these genes. As Mendal showed, they resort themselves every generation. What this study does is open a window into the mDNA of these royally-bred horses to see what they got. It by no means claim to be able to give a precise prediction of a horses ability or point out the next \"super horse\". What is does is show a correlation between a few genes from the dam and performance at different distances. Every little bit helps.

Bob

[bobphilo]

Bitplayer,

I've reviewed the study more closely and will try to answer your questions. It was conducted by geneticists Stephen Paul Harrison and Juan Luis Turrion-Gomez, and published in Mitochondrion- a peer-reviewed journal. They recognized several different haplotypes (gene arrangements) on mDNA, 5 of which correlate strongly with different racing abilities at 5 different distance ranges. The statistical methodology used was regression analysis and is presented in table and graphic form in the paper. Regression is a very effective way to show how different levels of one variable (genetic type) affect the values of another variable (racing performance).
Hope that answers your questions.

Bob

[bobphilo]

One additional note. Some of you will see a similarity between the goals of this study and Dosage theory. I think this study has 2 magor advantages over Dr. Roman\'s dosage. Dosage concentrates on sires and omits the important contribution of dams. Furthermore this study examines the specific mDNA of the induividual horse rather than trying to predict it from the pedigree.

Bob