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you have the C:T genotype. If you get two T’s, then you have a T:T genotype.
They found that two year olds that carried the (C:C) genotype had a muscle mass that was 7% greater than the T:T genotype. Thus, the C gene accounted for this increase in muscle mass.
Then, it was determined that there was a correlation to the optimum racing distance for each genotype. The C:C’s performed better at short distances, the C:T’s performed better at middle distances, and the T:T’s were better performers at longer distances that required more stamina.
The research by Dr. Hill and her colleagues lead to the genetic company Equinome and the testing for the speed gene as a selection tool for finding your racing prospects and their potential racing distance.
THE SOURCE
The continued research by Hill and fellow researchers, such as Dr. Mim Bower and colleagues at the University of Cambridge, UK, led to the announcement in early 2012 that they had traced the origin of the modern “C” speed gene to a single mare. They have reported that the source of the speed gene originated with what they call a “British-native mare.” This mare entered the picture about 300 years ago during the period that led to the foundation of the modern Thoroughbred.
A Science Daily website release in January 2012 summarized how the study unfolded to give them the information. The scientists took a look at a variety of Irish
and British breeds tracing to the “C” gene. They determined their findings through the study of almost 600 horses that represented 22 Eurasian and North American breeds using museum bone and tooth samples.
The samples came from 12 legendary Thoroughbred stallions, 330 elite modern Thoroughbreds, 40 donkeys, and two zebras. It was determined that a higher percentage of the “C” gene was found in the Shetland Pony
The Speed Gene is based on the role of the myostatin gene that directs the development of muscle mass in the foal, regulating factors that either allow or stop muscle development depending on the code that is passed on.
Hobby Mare that we get the family line of Domino going to Piping Peg’s Dam.
Some of the horses that trace to Pipping Peg’s Dam in the tail female line would include Triple Crown winner Affirmed, Kentucky Derby winner Ponder, Kentucky Derby winner Tim Tam, and Kentucky Derby winner Zev.
THE SPEED GENE
Our ability to study the genetics of the horse opened up when the sequencing of
the horse’s genome, or his genetic road map, was completed in 2007. A genome is defined as the full set of chromosomes that make
up an individual or the genetic makeup of an individual. This has allowed geneticists
to read and identify various genes, allowing them to follow the genetic road map that enables them to see how things work. The idea of determining an animal’s genome
was for the fight against genetic disease. But the racing industry has found other uses for identifying the genes, and that is to see how the genes affect athletic performance.
One of the breakthroughs came when Dr. Emmeline Hill and her colleagues at the School of Agriculture, Food Science, and Veterinary Medicine at the University College of Dublin, announced in 2011 that they had identified a genetic factor that enhances the ability of the racehorse to run fast. They discovered what geneticists have come to call the “Speed Gene.”
The Speed Gene is based on the role of the myostatin gene in the development of the foal.
The myostatin gene is the gene that directs the development of muscle mass in the foal. The myostatin gene is a regulatory
gene that controls other factors that either allow or stop muscle development, depending on the code passed on.
Some of the early references to the
working of myostatin came in dog breeding and with mice. Dr. Se-Jen Lee and Alexandra McPherron were geneticists who discovered the myostatin gene in 1997. They did it through their research with mice in which they developed a mutant gene that allowed a mouse to develop into a “super mouse” with twice as much muscle as their counterparts that didn’t carry the mutant gene. They were termed “Mighty Mice.” The super mouse gene didn’t stop muscle development and, thus, we had a true “Mighty Mouse” developed.
The other example came with the Whippet breed of dog and their racing ability. Whippets that have not inherited the myostatin gene are heavily muscled. Those that have one copy
of the myostatin gene had a middle of the road kind of muscle structure. The “mighty muscles” were useless for racing, and those with the middle of the road muscle structure were very good and even better than the whippets with no myostatin gene.
The Hill research team found two genetic codes for this gene. One of the gene types is identified as the C gene that allows muscle development, and the other is identified as a T gent that inhibits muscle development.
Let’s look at how it works. Each parent contributes either a C or T to the offspring, depending on their genetic makeup. Thus, you can have three genotypes based on
what each parent contributes. If each parent contributes a C, you have a C:C genotype. If one parent contributes a C and one a T, then
. . . the racing industry has found other uses for identifying the genes, and that is to see how the genes affect athletic performance.
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SPEEDHORSE, July 2016
SPEEDLINES