Marathon Chances Determined Through DNA Test
April 15, 2013

Genetic Test Could Determine Whether Or Not You Could Be A Marathon Runner

redOrbit Staff & Wire Reports - Your Universe Online

Researchers have developed a new DNA test that can allegedly determine whether or not a person is capable of completing a marathon — or at the very least, finishing in a respectable time.

According to Emily Davies of the Daily Mail, the genetic test, called XRPredict+, was developed by Jamie Timmons, the head of systems biology at Loughborough University. XRPredict+ focuses on a key group of 30 genes which determine how an individual´s body will respond to the stamina training required to complete such a long-distance race.

“If someone´s ambition is to do a marathon in a decent manner, we can tell them if they can based on their baseline fitness and their potential for responding to training,” Timmons told Richard Gray, Science Correspondent at The Telegraph.

“From our work, we know that 20 percent of people do not respond at all to training and in fact can get worse. They push themselves as hard as everyone else, but their muscles do not extract the same amount of oxygen,” he added. “About 15 percent have the genes that mean they will respond highly to training. But of that number, only those with a good inherited baseline fitness and good resistance to injury will ever become elite marathon runners.”

XRPredict+ focuses on the genes that are responsible for reshaping the body´s muscle fibers, making it possible for small blood vessels to grow in between them, the researchers explained. Those blood vessels help carry extra oxygen to the muscles during exercise, and individuals that possess the right combination of genes can more effectively remodel their muscles in response to regular long-distance running or other intense exercise.

One-fifth of all people lack the DNA to efficiently perform this muscular reshaping under the type of constant, high-intensity training used by runners to prepare for marathons. In some, it can reduce their body´s ability to carry oxygen to their muscles, thus actually causing their overall physical performance to decline. Timmons told Gray that anyone who falls into that category should abandon their dreams of becoming a long-distance runner.

“It is plausible that by pushing it though training, they get a maladaptation. What is clear is that there is no one recipe that fits all,” he said. “These low aerobic responders would be better going to the gym to build up their strength and muscle tissue or taking up other competitive sports like martial arts or strength related sports.”

Timmons also said that he plans to turn his attention to finding out how these 30 genes impact a runner´s potential for injury.

“The genes that underpin the development of the oxygen transport system also play an important role in ligaments and tendons as well. There may be a link between people who respond poorly to this sort of training and susceptibility to injury, but that still needs a lot of work,” the professor explained.

“We are still early in the life of this kind of use of genomics, but hopefully we will get better at being able to understand how genes determine people´s performance and be able to offer them advice,” he added. “This is important not just for those involved in sport for fun, but also from a health point of view — we want to be able to tailor the exercise people are doing so it is right for them.”