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Inherited Traits - Athletic Performance - ACTN3 - Considerations

Considerations based on your test result.  but_buythisproduct.gif 

Muscle fiber composition:  Fast twitch, Slow twitch

When you undergo genetic testing with Genomic Express, we will determine and report your ACTN3 genotype.  This gene encodes a protein that is expressed in fast skeletal muscle fibers.  There are three possible genotypes at your ACTN3 locus:  R/R, R/X, or X/X.   Your comprehensive report will include an explanation of how your genotype affects your muscle fibers, and the implications for athletic ability and performance.  Specifically, you will learn whether you are more likely to excel in power (e.g. short bursts of strength such as sprinting, weightlifting) or endurance events.  This may be useful information for choosing a sport, or field position within a sport, where you are more likely to excel.  Using track and swimming as an example, individuals with the "power" genotype might focus more on shorter distance sprints while individuals with the "endurance" genotype might focus on longer distance events. Your genetic information will also be useful for designing optimal training programs for whichever sport, position or event you choose..


Let Genomic Express help you learn more about your own genetics in order to choose an optimal approach to sports and athletic training.

Additional Information: 


Yang, N., et al. (2003)  ACTN3 Genotype is Associated with Human Elite Athletic Performance.  American Journal of Human Genetics 73, 627-631. 

MacArthur , D.G. and North, K.N. (2007)  ACTN3: A Genetic Influence on Muscle Function and Athletic Performance.  Exercise Sport Science Reviews 35 (1), 30-34.

Yang, N., et al. (2009)  alpha-Actinin 3 and Performance. Med. Sport Sci.54, 88-101.

            This genetic test is provided by Genomic Express, Inc. for educational and informational purposes only. It is not intended for the diagnosis or treatment of any diseases or disorders. Clients should consult with their own physician or other qualified health care provider for any medical or health needs. Genomic Express, Inc. shall not be held liable for any damages incurred as a result of the use of this information or caused by products described herein. 

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  • Genomic Express,Inc.
  • 725-H Lakefield Rd.
  • Westlake Village, CA 91361
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