ACTN3 R577X polymorphism is not associated with team sport athletic status in Italians

Polymorphisms of PPARα and ACTN3 Among Adolescent Egyptian Athletes: A Case-Control Study

BACKGROUND

Athletic performance is a complex phenotype affected by individual traits, environmental conditions, training, and genetics. The peroxisome proliferator-activated receptor-alpha (PPARα) and alpha-actinin-3 (ACTN3) are two genes with the potential to influence human performance. The objective of the present study was to assess the genotype frequencies of ACTN3 (R/X) and PPARα (G/C) and to conduct a comparison of these frequencies among Egyptian adolescent athletes.

METHODS

This case-control study involved 228 individuals (118 elite-level athletes and 110 sedentary controls).

RESULTS

This study identified a statistically significant increase in the frequencies of the ACTN3 'R' allele (77.5% compared to 55.9%; p < 0.001) and the PPARα 'C' allele (86.4% compared to 14.1%; p < 0.001) among athletes relative to the control groups. A similar pattern was noted for adolescent athletes in comparison to the control group in terms of both the R/R genotype (61.9% compared to 27.3%; p < 0.001) and the C/C genotype (80.5% compared to 2.7%; p < 0.001). In conclusion, these results imply that polymorphisms in ACTN3 and PPARα could be significant predictors for assessing the performance of adolescent Egyptian athletes.

ACE I/D Genotype and Risk of Non-Contact Injury in Moroccan Elite Athletes: A Pilot Study

Background and Objectives: The insertion/deletion (I/D) polymorphism in ACE, the gene encoding the angiotensin-converting enzyme (ACE), has been suggested as a genetic variation that can influence exercise performance and risk of injury in elite athletes. The I allele has been associated with enhanced endurance performance and with reduced inflammation, while the D allele has been associated with improved performance in strength and power activities. However, the role of this genetic variant in the incidence of non-contact injury is underexplored. This study investigated the possible association of ACE I/D genotypes with the risk of non-contact injury in elite Moroccan athletes. Materials and Methods: Forty-three elite male athletes (19 cyclists and 24 field hockey players) from the Moroccan national team participated voluntarily. Non-contact injuries were recorded for all athletes and classified according to the IOC consensus statement by the medical staff of the teams. ACE I/D polymorphism genotyping was performed by polymerase chain reaction (PCR) using genomic DNA from blood samples. Results: There were four cyclists (21.05%) and eight field hockey players (33.33%) with a non-contact injury during the season. The distribution of the ACE I/D genotypes was similar in the athletes with vs. without non-contact injury for cyclists (DD/ID/II 25.00/50.00/25.00% vs. 46.67/40.00/13.33% non-injured, respectively; X2 = 0.69, p = 0.70), field hockey players (DD/ID/II 50.00/50.00/0.00% vs. 50.00/43.75/6.25%; X2 = 0.54, p = 0.76) and for the whole group of athletes (DD/ID/II 41.67/50.00/8.33% vs. 48.39/41.94/9.68%; X2 = 0.22, p = 0.89). In the whole group of athletes, neither the dominant (DD + ID vs. II = OR: 1.17, 95% CI: 0.15-16.56, p = 0.89) nor the recessive (DD vs. ID + II = OR: 1.31, 95% CI: 1.31-4.89, p = 0.69) models showed an increased risk of non-contact injury. Conclusions: The distribution of the ACE I/D genotypes was similar in elite cycling and field hockey athletes with or without non-contact injury during the season. These results indicate that there is no significant association between the ACE I/D polymorphism and the susceptibility to non-contact injury in these athletes. Further research is warranted to validate these findings and to investigate their broader implications for advancing knowledge in sports injury prevention and optimizing athlete management strategies.

Influence of genetic polymorphism on sports talent performance versus non-athletes: a systematic review and meta-analysis

BACKGROUND

Talented athletes exhibit remarkable skills and performance in their respective sports, setting them apart from their peers. It has been observed that genetic polymorphisms can influence variations in sports performance, leading to numerous studies aimed at validating genetic markers for identifying sports talents. This study aims to evaluate the potential contribution of genetic factors associated with athletic performance predisposition in identifying sports talents.

METHODS

A systematic review was conducted following the PRISMA framework, utilizing the PICO methodology to develop the research question. The search was limited to case-control studies published between 2003 and June 2024, and databases such as Medline, LILACS, WPRIM, IBECS, CUMED, VETINDEX, Web of Science, Science Direct, Scopus and Scielo were utilized. The STREGA tool was employed to assess the quality of the selected studies.

RESULTS

A total of 1,132 articles were initially identified, of which 119 studies were included in the review. Within these studies, 50 genes and 94 polymorphisms were identified, showing associations with sports talent characteristics such as endurance, strength, power, and speed. The most frequently mentioned genes were ACTN3 (27.0%) and ACE (11.3%).

CONCLUSION

The ACE I/D and ACTN3 R577X polymorphisms are frequently discussed in the literature. Although athletic performance may be influenced by different genetic polymorphisms, limitations exist in associating them with athletic performance across certain genotypes and phenotypes. Future research is suggested to investigate the influence of polymorphisms in elite athletes from diverse backgrounds and sports disciplines.

A Systematic Review and Meta-analysis of the Association Between ACTN3 R577X Genotypes and Performance in Endurance Versus Power Athletes and Non-athletes

BACKGROUND

Previous studies reported differences in genotype frequency of the ACTN3 R577X polymorphisms (rs1815739; RR, RX and XX) in athletes and non-athletic populations. This systematic review with meta-analysis assessed ACTN3 R577X genotype frequencies in power versus endurance athletes and non-athletes.

METHODS

Five electronic databases (PubMed, Web of Science, Scopus, Science Direct, SPORTDiscus) were searched for research articles published until December 31st, 2022. Studies were included if they reported the frequency of the ACTN3 R577X genotypes in power athletes (e.g., weightlifters) and if they included a comparison with endurance athletes (e.g., long-distance runners) or non-athletic controls. A meta-analysis was then performed using either fixed or random-effects models. Pooled odds ratios (OR) were determined. Heterogeneity was detected using I2 and Cochran's Q tests. Publication bias and sensitivity analysis tests were computed.

RESULTS

After screening 476 initial registrations, 25 studies were included in the final analysis (13 different countries; 14,541 participants). In power athletes, the RX genotype was predominant over the two other genotypes: RR versus RX (OR 0.70; 95% CI 0.57-0.85, p = 0.0005), RR versus XX (OR 4.26; 95% CI 3.19-5.69, p < 0.00001), RX versus XX (OR 6.58; 95% CI 5.66-7.67, p < 0.00001). The R allele was higher than the X allele (OR 2.87; 95% CI 2.35-3.50, p < 0.00001) in power athletes. Additionally, the frequency of the RR genotype was higher in power athletes than in non-athletes (OR 1.48; 95% CI 1.25-1.75, p < 0.00001). The RX genotype was similar in both groups (OR 0.84; 95% CI 0.71-1.00, p = 0.06). The XX genotype was lower in power athletes than in controls (OR 0.73; 95% CI 0.64-0.84, p < 0.00001). Furthermore, the R allele frequency was higher in power athletes than in controls (OR 1.28; 95% CI 1.19-1.38, p < 0.00001). Conversely, a higher frequency of X allele was observed in the control group compared to power athletes (OR 0.78; 95% CI 0.73-0.84, p < 0.00001). On the other hand, the frequency of the RR genotype was higher in power athletes than in endurance athletes (OR 1.27; 95% CI 1.09-1.49, p = 0.003). The frequency of the RX genotype was similar in both groups (OR 1.07; 95% CI 0.93-1.24, p = 0.36). In contrast, the frequency of the XX genotype was lower in power athletes than in endurance athletes (OR 0.63; 95% CI 0.52-0.76, p < 0.00001). In addition, the R allele was higher in power athletes than in endurance athletes (OR 1.32; 95% CI 1.11-1.57, p = 0.002). However, the X allele was higher in endurance athletes compared to power athletes (OR 0.76; 95% CI 0.64-0.90, p = 0.002). Finally, the genotypic and allelic frequency of ACTN3 genes were similar in male and female power athletes.

CONCLUSIONS

The pattern of the frequencies of the ACTN3 R577X genotypes in power athletes was RX > RR > XX. However, the RR genotype and R allele were overrepresented in power athletes compared to non-athletes and endurance athletes. These data suggest that the RR genotype and R allele, which is associated with a normal expression of α-actinin-3 in fast-twitch muscle fibers, may offer some benefit in improving performance development in muscle strength and power.

Association between ACTN3 R577x and the physical performance of Chinese 13 to 15-year-old elite and sub-elite football players at different positions

The purpose of this study was to investigate the prevalence of ACTN3 polymorphisms in Chinese elite and sub-elite football players aged 13–15 years at different positions. Specifically we explored whether ACTN3 genotypes were linked with athletic performance of elite and sub-elite players at different positions. The RR genotype frequency of elite defenders (p = 0.018) and midfielders (p = 0.008) was significantly higher than that of sub-elite XX genotype in elite players. Furthermore, the R allele frequency of elite defenders (p = 0.003) and midfielders (p = 0.008) was significantly higher than that of sub-elite players. In all subjects, RR players performed faster and exhibited more explosive power than RX or XX players. RR, RX and XX elite players’ 20 m/30 m sprint, 5 × 25-m repeated sprint ability (5 × 25 m RSA), and standing long jump were stronger than sub-elite players, but there was no significant different in aerobic endurance between elite and sub-elite players at different positions. In conclusion, there were significant differences in ACTN3 genotypes and alleles between elite and sub-elite players at different positions, and the RR genotype was significantly associated with power-related athletic performance in Chinese youth football players.

Association between ACE and ACTN3 genes polymorphisms and athletic performance in elite and sub-elite Chinese youth male football players

Background

Previous studies have shown controversial relationships between ACE I/D and ACTN3 R577x polymorphisms and athletic performance. Therefore, the aim of this study was to assess athletic performance indicators of Chinese youth male football players with different ACE and ACTN3 gene profiles.

Methods and Materials

This study recruited 73 elite (26 13-year-olds, 28 14-year-olds, and 19 15-year-olds) and 69 sub-elite (37 13-year-olds, 19 14-year-olds, and 13 15-year-olds) and 107 controls (63 13-year-olds, and 44 14-year olds aged 13-15 years, all participants were of Chinese Han origin. We measured height, body mass, thigh circumference, speed, explosive power, repeat sprints ability, and aerobic endurance in elite and sub-elite players. We used single nucleotide polymorphism technology to detect controls elite and sub-elite players' ACE and ACTN3 genotypes, Chi-squared (χ ²) tests were employed to test for Hardy-Weinberg equilibrium. χ ² tests were also used to observe the association between the genotype distribution and allele frequencies between controls and elite and sub-elite players. The differences in parameters between the groups were analyzed using one-way analysis of variance and a Bonferroni's post-hoc test, with statistical significance set at p ≤ 0.05.

Results

(1) The genotype distribution of the ACE I/D and ACTN3 R577x polymorphisms in controls, elite and sub-elite football players were consistent with Hardy-Weinberg equilibrium, except for the ACE genotype distribution of sub-elite players. (2) The RR and DD genotypes were significantly different between elite and sub-elite players (p = 0.024 and p = 0.02, respectively). (3) Elite players were more likely to have the RR genotype and less likely to have the DD genotype compared with sub-elite players. (4) Both elite and sub-elite RR players' Yo-yo intermittent recovery level 1 (YYIR1) running distance was significantly longer than that of RX players (p = 0.05 and p = 0.025, respectively). However, there was no significantly different in YYIR1 running distance between elite and sub-elite RR players. (5) Elite XX players' VO₂ max was significantly higher than that of RX and sub-elite players.

Conclusion

These results indicate that ACE I/D and ACTN3 R577x polymorphisms are not associated with muscle power in Chinese elite and sub-elite players. The XX genotype of ACTN3 is associated with the aerobic endurance of elite players.

What Decides Your Athletic Career?-Reflection from Our Study of GP.Mur-Associated Sports Talents during the COVID-19 Pandemic Era

This opinion article discusses the factors that attract children and teens to athletic careers. The most important attribute for the making of athletes is polished sports talent, followed by psychological, environmental, and incentive factors. Our laboratory studies a red blood cell (RBC) type called GP.Mur, which is rare in most parts of the world besides Southeast Asia. Intriguingly, the prevalence of the GP.Mur blood type is relatively high among Taiwanese elite athletes. The highest frequency of the GP.Mur blood type worldwide is found among Taiwan's Ami people (88-95% from hospital blood bank surveys in the 1980s). Though the Ami constitute only 0.6-0.8% of the Taiwanese population, from records of national track-and-field games in the past century, 10-60% of the medalists were Ami. Biologically, GP.Mur expression supports blood CO₂ metabolism, which may have implications for athleticism. As many of our study subjects are elite college athletes with the GP.Mur blood type, we contemplated their upbringings and career dilemmas, especially during the difficult COVID-19 pandemic. Beyond individual sports talent, the pandemic particularly tests personal characteristics and socioeconomic support for becoming an athlete.

Association of Genetic Variances in ADRB1 and PPARGC1a with Two-Kilometre Running Time-Trial Performance in Australian Football League Players: A Preliminary Study

Genetic variants in the angiotensin-converting enzyme (ACE) (rs4343), alpha-actinin-3 (ACTN3) (rs1815739), adrenoceptor-beta-1 (ADRB1) (rs1801253), and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PPARGC1A) (rs8192678) genes have previously been associated with elite athletic performance. This study assessed the influence of polymorphisms in these candidate genes towards endurance test performance in 46 players from a single Australian Football League (AFL) team. Each player provided saliva buccal swab samples for DNA analysis and genotyping and were required to perform two independent two-kilometre running time-trials, six weeks apart. Linear mixed models were created to account for repeated measures over time and to determine whether player genotypes are associated with overall performance in the two-kilometre time-trial. The results showed that the ADRB1 Arg389Gly CC (p = 0.034) and PPARGC1A Gly482Ser GG (p = 0.031) genotypes were significantly associated with a faster two-kilometre time-trial. This is the first study to link genetic polymorphism to an assessment of endurance performance in Australian Football and provides justification for further exploratory or confirmatory studies.

Genetic association research in football: A systematic review

Genetic variation is responsible for a large amount of the inter-individual performance disparities seen in sport. As such, in the last ten years genetic association studies have become more common; with one of the most frequently researched sports being football. However, the progress and methodological rigour of genetic association research in football is yet to be evaluated. Therefore, the aim of this paper was to identify and evaluate all genetic association studies involving football players and outline where and how future research should be directed. Firstly, a systematic search was conducted in the Pubmed and SPORTDiscus databases, which identified 80 eligible studies. Progression analysis revealed that 103 distinct genes have been investigated across multiple disciplines; however, research has predominately focused on the association of the ACTN3 or ACE gene. Furthermore, 55% of the total studies have been published within the last four years; showcasing that genetic association research in football is increasing at a substantial rate. However, there are several methodological inconsistencies which hinder research implications, such as; inadequate description or omission of ethnicity and on-field positions. Furthermore, there is a limited amount of research on several key areas crucial to footballing performance, in particular; psychological related traits. Moving forward, improved research designs, larger sample sizes, and the utilisation of genome-wide and polygenic profiling approaches are recommended. Finally, we introduce the Football Gene Project, which aims to address several of these limitations and ultimately facilitate greater individualised athlete development within football.

Is mitochondrial DNA profiling predictive for athletic performance?

Mitochondrial DNA encodes some proteins of the oxidative phosphorylation enzymatic complex, playing an important role in aerobic ATP production; therefore, it can contribute to the ability to respond to endurance exercise training. The accumulation of mitochondrial mutations and the migratory processes of populations have given a great contribution to the development of haplogroups with a different distribution in the world. Several studies have shown the important role of gene polymorphisms in aerobic performance. In this review, some mitochondrial haplogroups and multiple rare alleles were taken into consideration and could be linked to the athlete's physical performance of different ethnic groups.

Association of the ACTN3 R577X (rs1815739) polymorphism with elite power sports: A meta-analysis

Objective

The special status accorded to elite athletes stems from their uncommon genetic potential to excel in world-class power sports (PS). Genetic polymorphisms have been reported to influence elite PS status. Reports of associations between the α-actinin-3 gene (ACTN3) R577X polymorphism and PS have been inconsistent. In light of new published studies, we perform a meta-analysis to further explore the roles of this polymorphism in PS performance among elite athletes.

Methods

Multi-database literature search yielded 44 studies from 38 articles. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were used in estimating associations (significance threshold was set at P^a ≤ 0.05) using the allele-genotype model (R and X alleles, RX genotype). Outlier analysis was used to examine its impact on association and heterogeneity outcomes. Subgroup analysis was race (Western and Asian) and gender (male/female)-based. Interaction tests were applied to differential outcomes between the subgroups, P-values of which were Bonferroni corrected (P_{interaction BC}). Tests for sensitivity and publication bias were performed.

Results

Significant overall R allele effects (OR 1.21, 95% CI 1.07–1.37, P^a = 0.002) were confirmed in the Western subgroup (OR 1.11, 95% CI 1.01–1.22, P^a = 0.02) and with outlier treatment (ORs 1.12–1.20, 95% CIs 1.02–1.30, P^a < 10⁻⁵–0.01). This treatment resulted in acquired significance of the RX effect in Asian athletes (OR 1.91, 95% CI 1.25–2.92, P^a = 0.003). Gender analysis dichotomized the RX genotype and R allele effects as significantly higher in male (OR 1.14, 95% CI 1.02–1.28, P^a = 0.02) and female (OR 1.58, 95% CI 1.21–2.06, P^a = 0.0009) athletes, respectively, when compared with controls. Significant R female association was improved with a test of interaction (P_{interaction BC} = 0.03). The overall, Asian and female outcomes were robust. The R allele results were more robust than the RX genotype outcomes. No evidence of publication bias was found.

Conclusions

In this meta-analysis, we present clear associations between the R allele/RX genotype in the ACTN3 polymorphism and elite power athlete status. Significant effects of the R allele (overall analysis, Western and female subgroups) and RX genotype (Asians and males) were for the most part, results of outlier treatment. Interaction analysis improved the female outcome. These robust findings were free of publication bias.

Polygenic Study of Endurance-Associated Genetic Markers NOS3 (Glu298Asp), BDKRB2 (-9/+9), UCP2 (Ala55Val), AMPD1 (Gln45Ter) and ACE (I/D) in Polish Male Half Marathoners

The purpose of this study was to investigate individually and in combination the association between the ACE (I/D), NOS3 (Glu298Asp), BDKRB2 (-9/+9), UCP2 (Ala55Val) and AMPD1 (Gln45Ter) variants with endurance performance in a large, performance-homogenous cohort of elite Polish half marathoners. The study group consisted of 180 elite half marathoners: 76 with time < 100 minutes and 104 with time > 100 minutes. DNA of the subjects was extracted from buccal cells donated by the runners and genotyping was carried out using an allelic discrimination assay with a C1000 Touch Thermal Cycler (Bio-Rad, Germany) instrument with TaqMan® probes (NOS3, UCP2, and AMPD1) and a T100™ Thermal Cycler (Bio-Rad, Germany) instrument (ACE and BDKRB2). We found that the UCP2 Ala55Val polymorphism was associated with running performance, with the subjects carrying the Val allele being overrepresented in the group of most successful runners (<100 min) compared to the >100 min group (84.2 vs. 55.8%; OR = 4.23, p < 0.0001). Next, to assess the combined impact of 4 gene polymorphisms, all athletes were classified according to the number of 'endurance' alleles (ACE I, NOS3 Glu, BDKRB2 -9, UCP2 Val) they possessed. The proportion of subjects with a high (4-7) number of 'endurance' alleles was greater in the better half marathoners group compared with the >100 min group (73.7 vs. 51.9%; OR = 2.6, p = 0.0034). These data suggest that the likelihood of becoming an elite half marathoner partly depends on the carriage of a high number of endurance-related alleles.

Concurrent exercise training: do opposites distract?

Specificity is a core principle of exercise training to promote the desired adaptations for maximising athletic performance. The principle of specificity of adaptation is underpinned by the volume, intensity, frequency and mode of contractile activity and is most evident when contrasting the divergent phenotypes that result after undertaking either prolonged endurance or resistance training. The molecular profiles that generate the adaptive response to different exercise modes have undergone intense scientific scrutiny. Given divergent exercise induces similar signalling and gene expression profiles in skeletal muscle of untrained or recreationally active individuals, what is currently unclear is how the specificity of the molecular response is modified by prior training history. The time course of adaptation and when 'phenotype specificity' occurs has important implications for exercise prescription. This context is essential when attempting to concomitantly develop resistance to fatigue (through endurance-based exercise) and increased muscle mass (through resistance-based exercise), typically termed 'concurrent training'. Chronic training studies provide robust evidence that endurance exercise can attenuate muscle hypertrophy and strength but the mechanistic underpinning of this 'interference' effect with concurrent training is unknown. Moreover, despite the potential for several key regulators of muscle metabolism to explain an incompatibility in adaptation between endurance and resistance exercise, it now seems likely that multiple integrated, rather than isolated, effectors or processes generate the interference effect. Here we review studies of the molecular responses in skeletal muscle and evidence for the interference effect with concurrent training within the context of the specificity of training adaptation.