| The Indian legend of The Three Blind Men and the | | | | exploders (powerlifters, long jumpers, and hurdlers) |
| Elephant is an apt metaphor for any random | | | | and those homozygous for the X allele (no protein |
| collection of three biotechnology entrepreneurs. Each | | | | expression) will become marathoners. |
| is raptly focused on his personal locus, blind to the | | | | This is a good fantasy, maybe, but not good science. |
| deep complexity just beyond his grasp. | | | | I was a terrific jumper when I was a teenager. At 6 |
| Of course, "entrepreneur" in the medical field is for | | | | feet tall, I could put the basketball on the rim. If I |
| many of us a code word for con artist. Recent news | | | | had two more inches, I could have dunked. I could do |
| from a "sports genetics" company (the concept itself | | | | a standing long jump of 8 feet, 6 inches. I was a |
| is an affront to science) follows closely on the heels | | | | sprinter for my junior high track team. |
| of several questionable corporate attempts to wrest | | | | As an adult, I was a runner. I ran 10K races for the |
| dollars from the unsuspecting. Ventures such as | | | | NYC Road Runners Club. Now 10K is not really |
| deCODE, Navigenics, and 23andMe are case study | | | | endurance, but it's almost an hour of running at my |
| exemplars of high-flying hype that has crashed to | | | | slower pace. For sure, that's not a 100-meter dash. |
| earth. Selling ACTN3 genetic tests is merely the | | | | The Times article mentions an Olympic long jumper |
| newest version of snake oil. | | | | who was homozygous for the X allele. By the |
| A New York Times article (1) discusses the rationale | | | | simplistic "sports gene" interpretation, he should have |
| for this type of testing, which is simplistic at best and | | | | been an endurance athlete. |
| crassly greed-inspired at worst. Recent work has | | | | These two counterexamples are not real evidence, |
| demonstrated an association between the ACTN3 | | | | but they make the point. Athletic performance results |
| 577R allele and elite sprint athletic performance. The | | | | from a rich amalgam of genetic, environmental, and |
| suggestion is that alpha-actinin-3 has a beneficial | | | | social factors. From the genetic viewpoint alone, |
| effect on fast-twitch skeletal muscle function. Also, | | | | regulatory feedback mechanisms make any |
| knockout mice who have lost ACTN3 expression | | | | phenotype a highly dynamic outcome. |
| demonstrate "a shift in muscle metabolism toward | | | | The downstream product of ACTN3 may be |
| the more efficient aerobic pathway" [OMIM | | | | alpha-actinin-3, but the one-to-one correspondence |
| description of ACTN3 Molecular Genetics].2 | | | | the company is promoting is just that - promotion. |
| The company wishes us to naively conclude that | | | | 1 Macur J: Born to run? Little ones get test for sports |
| individuals with the R allele will become sprinters and | | | | gene. The New York Times, November 29, 2008. |