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