ACTN3 R577X (rs1815739) Polymorphism and Athlete Status: An Additional Case–Control Association Study and Meta-Analysis

Abstract Chelly, A, Bouzid, A, Kammoun, I, Koubaa, H, Masmoudi, S, Chtourou, H, and Rebai, A. ACTN3 R577X (rs1815739) polymorphism and athlete status: An additional case–control association study and meta-analysis. J Strength Cond Res 39(10): e1233–e1242, 2025—The ACTN3 rs1815739 CC and TT genotypes have been suggested to be associated with power/mixed and endurance performance, respectively. However, results were in general controversial and inconclusive, and data concerning Tunisian athletes have not been established. First, we aimed to inspect the association between the ACTN3 R577X and athletes status using a meta-analysis, and second, to assess its association in Tunisian athletes. Using PubMed, Web of Science, and Scopus, 90 eligible articles (16,439 athletes, 36,349 controls) were found through May 2023. A total of 49 athletes (32 power, 17 mixed) and 49 sedentary healthy controls were recruited to collect blood samples for PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism). The meta-analysis revealed no significant association between rs1815739 polymorphism and endurance performance (odds ratio [OR] = 0.95; 95% confidence interval [CI] [0.86–1.04]). However, athletes with T allele were significantly associated with low power (OR = 0.71; 95% CI [0.65–0.79]) and mixed performance (OR = 0.95; 95% CI [0.87–1.02]). In addition, Tunisian athletes with CC genotype were more likely to have better power performance (OR = 0.71, 95% CI [0.5353–0.9373]). This study provides additional support to the literature findings about the association of rs1815739 polymorphism with power performance for the first time in Tunisian North-African athletes.