When we think of sports medicine, we usually think of doctors treating pulled muscles, torn ligaments, or other injuries related to the sport you play. But what if you could take a medical test that would tell you what sports you might be best suited for? It sounds like science fiction, but some people have already done exactly that.
This kind of genetic test uses your DNA to determine what type of sports you would excel at. Your DNA is the instruction book that tells your cells how to make you, and it makes you physically unique from everyone else on the planet (unless you have an identical twin!). DNA is made up of pieces of information called genes. If DNA is your instruction book, then each of your 20,000 or so genes would be a sentence in that book, each contributing a little bit of information. The words and letters in those sentences are made up of strings of coupled nucleic acid bases: Adenine, Thymine, Cytosine and Guanine.
A genetic test "reads" your gene sentences by identifying the order in which those bases occur. If just one of the bases is missing, out of order, or if there is an addition, the meaning of the entire sentence can be changed. Genetic tests can give your doctor important medical information: for example, there are tests that can determine whether or not you have a gene that will increase the chance of you developing diseases like cancer.
There are companies that will sequence your DNA for you. But knowing your genetic profile comes at a price: anywhere from $300 to $5000.
A company called Atlas Sports Genetics offers a genetic test to determine what sports an individual might excel at. Their test is based on a study that found that one gene, called ACTN3, influences whether you are better at endurance sports like long-distance running or power sports like sprinting.
The ACTN3 gene codes for the production of a protein by the same name, ACTN3 or alpha-actinin-3. When the protein is in abundance, it helps your muscle fibers fire rapidly and with a lot of force. These "fast twitch" muscles are associated with short, powerful bursts of energy, but they also use up oxygen rapidly, meaning you’ll tire more quickly. If you have the normal ACTN3 gene, you will have fast twitch muscles. However, there is a very common mutant form of the gene that leaves people with less alpha-actinin-3 protein. Their muscles don't move as fast or powerfully, but they are highly efficient at using oxygen. These "slow twitch" muscles give them greater endurance.
Did you know? The mutant, slow twitch version of ACTN3 is most common in people of Asian descent and least common in people of African descent.
Atlas is marketing its ACTN3 test to parents, to determine what type of sports their children should be enrolled in. But are these tests ethical or even accurate? Many of the athletes in the ACTN3 study had the “wrong” gene for the sport they played—including one Olympic long jumper from Spain. If his parents had him tested, would they have taken him out of long jumping and put him in a sport more “suited” to his genes? Studies have found that in national and international levels of sport competition, there are more people than usual with the "right" version of ACTN3 for their type of sport, but there are always people competing with the "wrong" gene version as well. The gene also seems to make more of a difference in power sports than in endurance sports. So while the right genes can help, they aren't the be all and end all of your sporting career. Training has just as much, if not more, influence on your success in a sport. So if you like a sport, invest in some good training rather than a genetic test.
Peak Performance. Heredity, genes and sports performance
Genetic testing of children for sports
Atlas Sports Genetics
Human Genome Project
I. I. Ahmetov et al, 2008. The ACTN3 R577X Polymorphism in Russian Endurance Athletes. British Journal of Sports Medicine 2010;44. 649-652.
L.-L. Chiu et al, 2011. ACTN3 Genotype and Swimming Performance in Taiwan. International Journal of Sports Medicine. 32 (6). 476-480.
N. Eynon et al, 2009. ACTN3 R577X Polymorphism and Israeli Top-level Athletes. International Journal of Sports Medicine. 30 (9). 695-698.
Article first published March 21, 2012