Investigation of the effect of ACTN-3 (R577X) gene on sprint performance in american football players

American football is a sports characterized by high-intensity, type II muscle fiber–dominant activities such as rapid changes in direction, sprinting, physical contact, acceleration, deceleration, and vertical jumping. Success in American football is closely associated with multidirectional movement capacity and high-level force production. In this regard, change-of-direction ability, sprint speed, and vertical jump performance are critical determinants of athletic performance. As in other sports disciplines, athletic performance and success in American football are shaped by both environmental factors—such as training and equipment—and genetic components. Sports genetics is a field that investigates the influence of genetic variations on athletic traits. Accurate identification and analysis of such variations can enhance talent identification and enable the development of individualized training programs tailored to athletes' genetic profiles. The present study aimed to investigate the relationship between the ACTN-3 R577X (rs1815739) polymorphism and sprint performance in male athletes competing in the Turkish Professional American Football League. A total of 53 male athletes aged between 18 and 30 years were recruited for the study. Participants underwent standardized performance tests, including the vertical jump, 3-cone drill, and 40-yard sprint. Buccal epithelial cell samples were collected from all participants, and DNA was extracted for genotyping. The ACTN-3 R577X polymorphism was analyzed using the polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) method. Genotype distributions were then evaluated in relation to the athletes' performance test outcomes. An analysis of the participants' polymorphism distributions revealed that 35.8% (n=19) had the CC genotype, 49.1% (n=26) had the CT genotype, and 15.1% (n=8) had the TT genotype. Regarding allele frequencies, the C allele was found to be distributed at a rate of 60.4% (n=64), while the T allele accounted for 39.6% (n=42). In conclusion, the findings of this study are generally consistent with the literature suggesting that the ACTN-3 R577X polymorphism may lead to performance differences in motor tasks requiring sprinting and explosive power.