Determination of ACTN3 genotypes: A Muscle Protein Gene Polymorphism Related to Athletic Performance

Indianapolis, IN

The ACTN3 gene encodes for the?-actinin skeletal muscle isoform 3 (F-actin cross-linking protein) which binds to the actin in skeletal muscle. These muscle fibers are divided into two categories: fast twitch and slow twitch. As their names suggest, fast- twitch rapidly generate force for powerful motion while slow-twitch utilize oxygen more efficiently over long periods of time for endurance motion. A common polymorphism within the human population has been correlated to athletic performance, with the non-mutant allele indicating high levels of fast twitch muscle fibers and the mutant allele indicating high levels of slow twitch muscle fibers. We have developed a reliable method for determining the ACTN3 genotype of human subjects using PCR amplification and restriction enzyme digestion. This method is being used to test for a correlation between the genotype and athletic performance measured within a population of college football players using a variety of exercise testing factors.