Speed Gene Test Could Offer Clues On Yearling Returns

Speed Gene Test Goes Could Offer Clues On Yearling Returns

This article, entitled Speed Gene Test Goes Beyond Track Performance; Could Offer Clues On Yearling Returns, was originally published in the Paulick Report on 31st July 2019.[vc_single_image image=”11154″ img_size=”full” alignment=”center”]Pedigree is at the core of the Thoroughbred horse industry. For centuries, breeders and trainers have looked to the achievements and traits of previous generations with a view to making successful breeding or racing decisions. One only has to look at yearling returns at sales with a bloodline perceived as attractive to understand the value that is assigned to pedigree.

In recent years, there has been increasing discussion about the use of genetic tools for Thoroughbreds. However, when you think about it, genetics is essentially just a more scientific and higher resolution version of pedigree.

“Pedigree is like seeing the world in black and white, we can now put colour and dimension on that pedigree by using genetics,” said Professor Emmeline Hill, chief scientific officer of Plusvital.

Genetics is Pedigree 2.0.


Genetic Code

Every cell in a Thoroughbred horse’s body contains DNA. This DNA contains a huge volume of information, 2.7 billion base pairs or building blocks separated into 15 thousand separate genes. Each gene is inherited 50% from the sire and 50% from the dam at the point of fertilization and is fixed from that point with the same DNA code in every cell.

These genes contain all the information the horse reads and follows to function in all aspects of life. Understanding these genes, how they are inherited, how they function and how they differ between horses is at the core of equine genetics.

Because this genetic code is set from the moment of conception, genetics can supply information about an individual horse when it is only a foal – before it is even possible to assess traits visually. For example, traits such as full-grown height, precocity and muscle mass size as a 2-year-old can be difficult to predict in a one week old foal. However, genetic testing of the same foal can provide insights into the physical makeup it will achieve as a 2-year-old and older.


The Speed Gene Test

A good example of such a genetic test providing this type of information is the Speed Gene Test. This test examines one gene in the horse called the Myostatin or ‘Speed Gene‘. This gene controls the rate of development of muscle in the horse and the type of muscle that is formed (fast-twitch or slow-twitch). As the Thoroughbred horse has such a high level of muscling, any difference in muscling caused by genetic variations is likely to have a significant effect on performance. Multiple studies have shown that there effectively three types of Speed Gene which are colloquially known as C:C, C:T, and T:T.

C:C horses tend to have more muscle and more fast-twitch muscle meaning they are more precocious and best suited to sprint distances (5-8 furlongs). They tend to perform well at yearling sales.

C:T horses have a good mix of fast-twitch and slow twitch muscles meaning they are suited to middle distances (6-10 furlongs).

T:T horses have a predominance of slow-twitch muscles making them best suited to longer distance races (8 furlongs plus)

It is often suggested that pedigree can provide the same information. However, the way the Speed Gene type is inherited refutes that suggestion. It’s entirely possible that the same mating can create any of the three Speed Gene types. The pedigree page would be the exact same in each instance but the genetic type, and hence the performance of that horse, would be very different. Genetics can provide information beyond that contained within the pedigree.[vc_single_image image=”11156″ img_size=”full” alignment=”center”]

Yearling Returns

Smart breeders have already started to use the Speed Gene Test to improve their yearling returns at sales. As we have seen, C:C horses tend to be more forward types due to their increased muscle gain at an earlier age. This would suggest that horses with this genetic profile are best suited for earlier sales where this clear physical difference will be rewarded. Case-studies back this up with a recent study on over 500 horses at an Australian premier yearling sales showing that C:C horses tended to sell for 27% more than C:T types and 53% more than T:T types. Similarly, a study at a Horses in Training sale in the USA showed that C:C horses had an average price 48% higher than C:T types and 75% higher than T:T types. If you are targeting these types of sales, then ideally you should be bringing C:C horses.

However, if you understand that C:T and T:T types will come into their own as 3-year-olds, then there may be an opportunity to use this information to your advantage. Either send these horses to sales that are less likely to prioritise precocity or to sales when the horse is older and has physically caught up. Perhaps there is an opportunity to purchase C:T or T:T types at a sale knowing that they may be under-valued. Ultimately, if a buyer has ambitions of winning a Triple Crown race then they will need a C:T or T:T horse and for all their precocity a C:C type is unlikely to make those distances.

Clearly, understanding the Speed Gene type of your foal can provide significant financial benefits by informing sales decisions. Once you understand that you can tip the scale towards producing foals with your preferred Speed Gene type too, by knowing the Speed Gene type of the mare, the value of the test becomes even more apparent.

At only $350 per test, can you afford not to know what speed gene type your horse is? Learn more about Plusvital’s cutting-edge genetic tests here.

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