R577X Genotype Research Articles

ACTN3 XX Genotype Negatively Affects Running Performance and Increases Muscle Injury Incidence in LaLiga Football Players.

The aim of this study was to investigate the association of the ACTN3 rs1815739 polymorphism with match running performance and injury incidence in top-level professional football players. A total of 315 top-level professional football players from the first division of Spanish football (i.e., LaLiga) participated in this prospective and descriptive study. The ACTN3 rs1815739 genotype was identified for each player using genomic DNA samples. During LaLiga 2021-2022, players' performance was obtained through a validated camera system in all official matches. Additionally, the incidence of non-contact injuries was obtained by each team's medical staff according to the International Olympic Committee (IOC) statement. From the study sample, 116 (36.8%) players had the RR genotype, 156 (49.5%) had the RX genotype, and 43 (13.7%) had the XX genotype. The anthropometric characteristics of the players were similar across genotypes. However, the total running distance (p = 0.046), the distance at 21.0-23.9 km/h (p = 0.042), and the number of sprints (p = 0.042) were associated with the ACTN3 genotype. In all these variables, XX players had lower match performance values than RR players. Additionally, total and match injury incidences were higher in XX players than in RR players (p = 0.026 and 0.009, respectively). The rate of muscle injuries was also higher in XX players (p = 0.016). LaLiga football players with the ACTN3 XX genotype had lower match running performance and a higher incidence of non-contact injuries over the season.

Association of ACTN3 R577X Genotype with Physical Fitness in Japanese Male College Students

Association of ACTN3 R577X Genotype with Physical Fitness in Japanese Male College Students

The Association between ACTN3 R577X Polymorphism and Range of Motion: A Systematic Review and Meta-analysis.

The R577X polymorphism in the α-actinin-3 gene (ACTN3) is associated with muscle strength and power; there is an association between ACTN3 R577X polymorphism and range of motion (ROM). We examined the effect of the ACTN3 R577X polymorphism on ROM through meta-analysis and systematic review. Relevant studies published before April 14, 2022 were identified from the PubMed database using the following keywords and Boolean operators: ("flexibility" or "Joint Range of Motion" or "Joint Flexibility" or "Range of motion") and ("ACTN3" or "alpha-actinin 3"). Studies that met the following criteria were included: (1) published in English, (2) included human subjects, (3) provided ROM measurements, and (4) analyzed the ACTN3 R577X genotype. A total of 2908 participants from seven studies were included in the meta-analysis. The additive genetic model was assessed using a meta-regression model, and dominant and recessive models were analyzed using a random effects model. The ROM in the XX+RX genotype was significantly higher than that in the RR genotype (recessive model: p<0.001), and it increased additively in the order XX>RX>RR (additive model: p=0.029). However, no significant association was observed in the dominant model. These findings further elucidate the association between flexibility and the ACTN3 R577X genotype.

Genotype Distribution of the ACTN3 p.R577X Polymorphism in Elite Badminton Players: A Preliminary Study.

α-Actinin-3 is a protein with a structural role at the sarcomeric Z-line in skeletal muscle. As it is only present in fast-type muscle fibers, α-actinin-3 is considered a key mechanical component to produce high-intensity muscle contractions and to withstand external tension applied to the skeletal muscle. α-Actinin-3 is encoded by the gene ACTN3, which has a single-nucleotide polymorphism (p.R577X; rs1815739) that affects the expression of α-actinin-3 due to the presence of a stop codon. Individuals homozygous for the 577R allele (i.e., RR genotype) and RX heterozygotes express functional α-actinin-3, while those homozygous for the 577X (i.e., XX genotype) express a non-functional protein. There is ample evidence to support the associations between the ACTN3 genotype and athletic performance, with higher frequencies of the 577R allele in elite and professional sprint and power athletes than in control populations. This suggests a beneficial influence of possessing functional α-actinin-3 to become an elite athlete in power-based disciplines. However, no previous investigation has determined the frequency of the ACTN3 genotypes in elite badminton players, despite this sport being characterized by high-intensity actions of intermittent nature such as changes of direction, accelerations, jumps and smashes. The purpose of this study was to analyze ACTN3 R577X genotype frequencies in professional badminton players to establish whether this polymorphism is associated with elite athlete status. A total of 53 European Caucasian professional badminton players competing in the 2018 European Badminton Championships volunteered to participate in the study. Thirty-one were men (26.2 ± 4.4 years) and twenty-two were women (23.4 ± 4.5 years). Chi-squared tests were used to analyze the differences in the distribution of ACTN3 genotypes (RR, RX and XX) between categories and sexes. The ACTN3 RR genotype was the most frequent in the sample of professional badminton players (RR = 49.1%, RX = 22.6% and XX = 28.3%). None of the badminton players ranked in the world's top ten possessed the XX genotype (RX = 60%, RR = 40%). The distribution of the ACTN3 genotypes was similar between male and female professional badminton players (men: RR = 45.2%, RX = 25.8% and XX = 29.0%; women: RR = 54.5%, RX = 18.2% and XX = 27.3%; χ2 = 0.58; p = 0.750). The distribution of the ACTN3 genotypes in badminton players was different from the 1000 genome database for the European population (χ2 = 15.5; p &lt; 0.001), with an overrepresentation of the RR genotype (p &lt; 0.05) and an underrepresentation of the RX genotype (p &lt; 0.01). In conclusion, the expression of functional α-actinin-3, associated with RR and RX genotypes in the ACTN3 gene may confer an advantage for reaching the status of elite athlete in badminton, and especially the world's top-ten ranking. Large-scale studies with different ethnic backgrounds are needed to confirm the association of the R allele of ACTN3 with badminton performance.

A Pilot Study on the Prediction of Non-Contact Muscle Injuries Based on ACTN3 R577X and ACE I/D Polymorphisms in Professional Soccer Athletes.

Muscle injuries are among the main reasons for medical leavings of soccer athletes, being a major concern within professional teams and their prevention associated with sport success. Several factors are associated with a greater predisposition to injury, and genetic background is increasingly being investigated. The aim of this study was to analyze whether ACTN3 R577X and ACE I/D polymorphisms are predictors of the incidence and severity of muscle injury in professional soccer athletes from Brazil, individually and in association. Eighty-three professional athletes from the first and second divisions of the Brazilian Championship were evaluated regarding the polymorphisms through blood samples. Nighty-nine muscle injuries were identified during the seasons of 2018, 2019 and 2020 and categorized according to severity. ACTN3 XX individuals had a higher frequency of severe injuries compared to the RX and RR genotypes (p = 0.001), and in the dominant model (compared to RX+RR), with p < 0.001. The trend p-value test showed an increased number of injuries/season following the order XX > RX > RR (p = 0.045). Those with the ACE II genotype had almost 2 fold the number of injuries per season compared to those with the ID+DD genotypes (p = 0.03). Logistic regression showed that the polymorphisms are predictors of the development of severe injury (ACTN3 R577X model with p = 0.004, R2: 0.259; ACE I/D model with p = 0.045, R2: 0.163), where ACTN3 XX individuals were more likely to suffer from severe injury (OR: 5.141, 95% CI: 1.472-17.961, p = 0.010). The combination of the ACTN3 577X allele and the ACE II genotype showed an increased number of injuries per season, enhanced by 100% (1.682 injuries/season versus 0.868 injuries/season, p = 0.016). Our findings suggest that both polymorphisms ACTN3 R577X and ACE I/D (and their interaction) are associated with the susceptibility and severity of non-contact muscle injury in soccer players.

Association of the ACTN3 rs1815739 Polymorphism with Physical Performance and Injury Incidence in Professional Women Football Players.

The p.R577X polymorphism (rs1815739) in the ACTN3 gene causes individuals with the XX genotype to be deficient in functional α-actinin-3. Previous investigations have found that XX athletes are more prone to suffer non-contact muscle injuries, in comparison with RR and RX athletes who produce a functional α-actinin-3 in their fast-twitch fibers. This investigation aimed to determine the influence of the ACTN3 R577X polymorphism on physical performance and injury incidence of players competing in the women’s Spanish first division of football (soccer). Using a cross-sectional experiment, football-specific performance and epidemiology of non-contact football-related injuries were recorded in a group of 191 professional football players. ACTN3 R577X genotype was obtained for each player using genomic DNA samples obtained through buccal swabs. A battery of physical tests, including a countermovement jump, a 20 m sprint test, the sit-and-reach test and ankle dorsiflexion, were performed during the preseason. Injury incidence and characteristics of non-contact injuries were obtained according to the International Olympic Committee (IOC) statement for one season. From the study sample, 28.3% of players had the RR genotype, 52.9% had the RX genotype, and 18.8% had the XX genotype. Differences among genotypes were identified with one-way analysis of variance (numerical variables) or chi-square tests (categorical variables). Jump height (p = 0.087), sprint time (p = 0.210), sit-and-reach distance (p = 0.361), and dorsiflexion in the right (p = 0.550) and left ankle (p = 0.992) were similar in RR, RX, and XX football players. A total of 356 non-contact injuries were recorded in 144 football players while the remaining 47 did not sustain any non-contact injuries during the season. Injury incidence was 10.4 ± 8.6, 8.2 ± 5.7, and 8.9 ± 5.3 injuries per/1000 h of football exposure, without differences among genotypes (p = 0.222). Injury rates during training (from 3.6 ± 3.7 to 4.8 ± 2.1 injuries per/1000 h of training exposure, p = 0.100) and match (from 47.8 ± 9.5 to 54.1 ± 6.3 injuries per/1000 h of match exposure, p = 0.209) were also similar in RR, RX, and XX football players. The ACTN3 genotype did not affect the mode of onset, the time needed to return to play, the type of injury, or the distribution of body locations of the injuries. In summary, women football players with different genotypes of the p.R577X ACTN3 polymorphism had similar values of football-specific performance and injury incidence. From a practical perspective, the ACTN3 genotyping may not be useful to predict performance or injury incidence in professional women football players.

The Association of ACTN3 Rs1815739 Polymorphism with Various Malocclusion Phenotype

A functional polymorphism on the 16th exon of the alpha-actinin-3 gene has an effect on the protein structure and cellular signaling and therefore on muscle contraction. In this study, we aimed to analyze the alpha-actinin-3 rs1815739 polymorphism in 3-dimensional malocclusions and different craniofacial skeletal patterns. Forty-nine volunteering subjects enrolled for the study. Genotyping of alpha-actinin-3 rs1815739 polymorphism was per- formed using real-time polymerase chain reaction. Pre-orthodontic cephalometric radiographs were traced using NemoTech ceph- alometric tracing software. IBM SPSS Statistics for Windows was utilized to carry out statistical analysis. P < .05 was considered to be statistically significant. The respective numbers and the percentages of alpha-actinin-3 rs1815739 polymorphisms for RR, RX, and XX genotypes were 39 (79.6%), 4 (8.2%), and 6 (12.2%), respectively. Twenty-one patients had low angle vertical patterns and 17 patients had Class I and the same number of the patients had Class III facial patterns. But none of these had statistically significant difference in terms of alpha-actinin-3 rs1815739 polymorphism and in vertical or sagittal facial patterns, and mandibular incisor inclination. When we examined the maxillary anteroposterior position, we found a significant difference between rs1815739 polymorphisms (P < .05). Also, we detected a significant difference between rs1815739 polymorphism and maxillary incisor inclination (P < .05). Maxillary incisor inclination and maxillary anteroposterior position are associated with alpha-actinin-3 rs1815739 poly- morphism in a Turkish cohort.

Comparison of potential biomarker, ACTN3 rs1815739 polymorphism, for athletic performance of Turkish athletes.

α-Actinin-3 is one of the key components of the Z-line structure of sarcomeres and also have importance in muscle cell signaling processes. Therefore, α-Actinin-3 gene rs1815739 polymorphism is one of the most analysed potential genetic biomarkers in sports genetic studies. We aimed to evaluate the genotypic and allelic distribution of α-Actinin-3 gene rs1815739 polymorphism in Turkish athletes. For this purpose, a total of 131 athletes (39 cyclists, 34 sprinters and distance athletes, 33 volleyball players, 15 bodybuilders and 10 ironmen) and 89 sedentary individuals were enrolled in the study. Genomic DNA from venous blood were isolated by using the PureLink DNA isolation kit by following the manufacturers' instructions. The α-Actinin-3 rs1815739 genotyping was carried out by Real-time PCR using the commercially provided Taqman Genotyping Assay. The statistical evaluations were assessed by the chi-square testing using the GraphPad InStat statistical package. Results showed that cyclists, ironmen and volleyball players showed statistically significant differences in terms of the genotype when compared to the controls. The OR of having the dominant trait (RR genotype vs. RX+XX combined) was 0.5 (95%CI: 0.28-0.91; P= 0.02) which was statistically significant, while the OR of having the recessive trait (XX genotype vs. RR+RX combined) was 3.76 (95%CI: 1.82-7.39; P=0.0002). Our findings indicated that the α-Actinin-3 gene rs1815739 RR genotype was more prevalent in the sprinters and distance athletes. In the bodybuilders, cyclists, and ironmen it was found that they were harboring the RR and RX genotype equally. According to the results, we suggest the α-Actinin-3 rs1815739 as a potential biomarker for personal training programs.

ACTN3 R577X variant: could it be a determinant of sports performance in elite athletes in a Turkish population?

ACTN3 gene, which encodes a-actinin-3 and actin-binding protein, has been found to be associated with strong athletic performance, especially among track and field athletes. Therefore, in this study, our aim was to compare the allelic and genotype frequencies of the ACTN3 R577X variant among elite athletes specialized in different branches, and nonathletic controls in Turkey. In the present study, 316 subjects, including 168 athletes and 148 sedentary controls were genotyped for the ACTN3 R577X variant. Genotyping was conducted by polymerase chain reaction (PCR) method. Additionally, we evaluated the groups by dividing them as females and males. There were 48 females and 120 males in the athletes group, and 43 females and 105 males in the control group. Genetic associations were evaluated by chi-squire test or Fisher's exact test. There was a significant difference between the athletes and controls in terms of the ACTN3 R577X variant. ACTN3 RR and XX genotypes increased in the controls compared to the athletes, while RX genotype was higher in the athletes than the controls (P = 0.030). Then we evaluated the groups by separating them as females and males. Genotype distribution of the ACTN3 R577X differed between the male athletes and the male controls (P = 0.046). ACTN3 R577X RX genotype increased in the male athletes compared to the male control (P = 0.046). But ACTN3 R577X genotype and allele distribution was not significant between female athletes and female control group (P>0.05). As far as we know, this study is the largest series examining the ACTN3 R577X variant in Turkish athletes. Our results support that the ACTN3 R577X variant has a heterozygous advantage in athletic performance in the Turkish population. However, epigenetic, gene-gene and gene-environment interactions affects athlete performance should not be forgotten.

Genetic profile of sports climbing athletes from three different ethnicities.

This study aimed to investigate the ACTN3 R577X, ACE I/D, CKM rs8111989, and TRHR rs7832552 genotypes in climbers and controls in three ethnicities. The study consisted of 258 climbers (Japanese, n = 100; Polish, n = 128; Russian, n = 30) and 1151 controls (Japanese: n = 332, Polish: n = 635, Russian: n = 184). Genotyping results were analyzed using the TaqMan approach in Japanese and Polish subjects and HumanOmni1-Quad Bead Chips in Russian subjects. There were no significant differences in ACTN3 R577X and ACE I/D polymorphism distribution between climbers and controls in any ethnic cohort or model. The frequencies of the C allele in the CKM polymorphism and the T allele in the TRHR polymorphism were higher in climbers than in controls only in the Russian cohort (p = 0.045 and p = 0.039, respectively). The results of the meta-analysis on three cohorts showed that the frequency of XX + RX genotypes in the ACTN3 R577X polymorphism was significantly higher in climbers than that in the controls (p = 0.01). The X allele of the ACTN3 R577X polymorphism was associated with sport climbing status, as assessed using a meta-analysis of climbers across three different ethnicities.

Speed and power-related gene polymorphisms associated with playing position in elite soccer players.

Heritability studies on sport-related traits accepted that endurance, speed, power, and strength abilities include an active genetic predisposition to elite soccer participation. This study evaluates the influence of selected genetic variants on performance in speed, power, and strength laboratory tests on a group of elite soccer players, including their playing position. A ninety-nine male elite soccer players were compared to controls (n = 107) and tested for quadriceps and hamstrings isokinetic strength at speed 60°/s, 180°/s, and 300°/s, jump performance, and genotypes of ACTN3 (R577X, rs1815739), ACE (I/D, rs1799752), NOS3 (Glu298Asp, rs1799983), AMPD1 (34C/T, rs17602729), UCP2 (Ala55Val, rs660339), BDKRB2 (+9/-9, rs5810761) and IL1RN (VNTR 86-bp). The ACTN3 XX homozygotes in defenders had lower quadriceps and hamstring isokinetic strength in all tested speeds than ACTN3 RX and RR genotypes (p < 0.05). The ACTN3 RR homozygotes in defenders had higher quadriceps strength in all tested velocities than the RX heterozygotes (p < 0.05). We also found other associations between playing-position in soccer and increased strength of lower limbs for AMPD1 CC and NOS3 Glu/Glu genotypes, and IL1RN*2 allele carriers. Total genetic score regression explained 26% of the variance in jump performance and isokinetic strength. The ACTN3 R allele, NOS3 Glu/Glu genotypes, and IL1RN*2 allele pre-disposed the attackers and defenders playing position in elite soccer, where those positions have higher strength and power measures than midfielders. Midfielders have lower strength and power conditions than other playing positions without relation to strength and power genes.

Can a genetic profile be related to performance in young talent track and field athletes? A pilot study

Aim: This study analyzed the influences of ACE and ACTN3 gene variants in sprinters, jumpers, and endurance young athletes of track and field. Methods: 36 school-level competitors of both sex (15 girls and 21 boys; aged 16.4 ± 1.2 years; training experience 4 ± 1.2 years) practitioners of different sport disciplines (i.e., sprint, jump, and endurance athletes) participated in the study. The deoxyribonucleic acid (DNA) was extracted from peripheral blood using a standard protocol. Anthropometric measurements, 30 m sprint, squat jump (SJ), and maximal oxygen uptake (VO2max) tests were measured. Results: Genotype distribution of the ACE and ACTN3 genes did not differ between groups. In ACE DD and ACTN3 RX genotypes, the SJ test was bigger in sprinters and jumpers than in the endurance runners. In contrast, when analyzing the ACE ID genotype, sprinters had higher SJ than endurance athletes. Moreover, in the ACE DD genotype, the sprinters and jumpers’ athletes had lower time in 30 m tests compared to endurance runners. However, the ACE ID and ACTN3 RX genotypes was greater aerobic fitness in endurance runners than in jumpers’ athletes. Conclusion: Although the genetic profile is not a unique factor for determining athletic performance, the ACE DD and ACTN3 RX genotypes seem to favor athletic performance in power and sprint versus endurance sports. Thus, this study evidenced that assessing genetic variants could be used as an auxiliary way to predict a favorable profile for the identification of young talents of track and field.

Genetic correlates of creativity in military personnel under extreme conditions of the Arctic Zone of the Russian Federation: a pilot study

BACKGROUND: The ability of a person in the process of active activity to adapt to changing environmental conditions is largely related to his creative potential. Creativity, like other physical and mental personality traits, has its own genetic base, which has not been sufficiently studied to date. Certain genes involved in this process are regularly described. The search for an association with new candidate genes for the creative potential of practically healthy, young respondents selected for work in the extreme conditions of the North is extremely important in the selection of people for work and service in difficult conditions. AIM: Search for the correlation of candidate gene polymorphism and the psychological state of the examined. MATERIALS AND METHODS: The psychological block of the pilot study included determining the degree of creativity, as well as the degree of tension of key psychological defense mechanisms. All the techniques used within its framework are part of the standard psychodiagnostic tools that have been tested in domestic conditions. Genotyping was performed by real-time PCR, determining the corresponding alleles of candidate genes, and then the data were compared by the method of analysis of variance. RESULTS: As candidate genes, we selected the angiotensin-converting enzyme gene, the serotonin 2A receptor gene, the neurotrophic factor BDNF, and alpha-actinin-3. According to the literature, all these genes are associated with the ability to adapt and / or psychotic states, which suggests their possible connection with creativity. The most interesting results are associated with the polymorphism of the BDNF gene: respondents with the BDNF Val/Val genotype are characterized by the maximum level of creativity and the minimum level of intensity of basic psychological defenses and coping strategies by types of distancing, as well as seeking social support. On the contrary, their maximum level is associated with the Met/Met genotype. Thus, it has been reliably shown that optimal adaptation to extreme external conditions is most likely to be ensured genetically by the presence of the Val / Val genotype, and psychologically by enhanced use of creative ability. The respondents with the ACTN3 RX genotype (with increased cold resistance) are characterized by a minimum level of creativity, and those with the RR genotype its maximum level. It is also shown that respondents with the ACE DD genotype are characterized by a minimum level of creativity. There were no associations with creativity with the serotonin 2A receptor gene polymorphism. CONCLUSIONS: The totality of the results obtained as a result of this pilot study allows us to consider a systematic study of creative ability and its molecular biological correlates to be correct and constructive for the development of a fundamental problem of the interaction of molecular biological and psychological mechanisms that provide active adaptation, as well as very expedient for solving the complex. scientific and applied tasks for the selection and correction of the state of persons directed to work in special and / or extreme conditions.

Associations of alpha-actinin-3 genotype with thigh muscle volume and physical performance in older adults with sarcopenia or pre-sarcopenia.

This cross-sectional study aimed to investigate the relationship of the ACTN3 genotype with thigh muscle volume and physical performance in older adults with sarcopenia or pre-sarcopenia. Data from 64 older Japanese adults (mean age 74.4±6.9years, women 71.9%) with sarcopenia or pre-sarcopenia were analyzed. Sarcopenia and pre-sarcopenia were defined using the Asian Working Group for Sarcopenia. We collected oral mucosa samples to determine the ACTN3 genotype. Thigh muscle volumes were measured using magnetic resonance imaging. Physical performance was assessed using the usual and maximum gait speed, timed up and go test, and five-repetition sit-to-stand test. Muscle strength was assessed using grip strength. The ACTN3 genotype proportions were 20.3% for RR, 51.6% for RX, and 28.1% for XX. Participants with the RR genotype showed greater thigh muscle volume/ht2 compared to those with the RX and XX ACTN3 genotypes (p<0.05). The multiple linear regression analysis revealed that RX (p<0.01) and XX (p<0.01) ACTN3 genotypes, compared to RR, were associated with lower thigh muscle volume/ht2 and with age, sex (reference; men), weight and maximum walking speed. There was no significant difference between physical performance and muscle strength between the ACTN3 genotypes. The ACTN3 genotype of the X allele was associated with decreased thigh muscle volume compared to the ACTN3 genotype of RR in older adults with sarcopenia or pre-sarcopenia.

A molecular insight in sport and athletic alpha – actin3 gene in students of Physical Education Faculty and bodybuilders.

Alpha – actin3 is gene for athletic performance and sport. Three types of genotypes were identified within the gene: RR homozygous, RX heterozygous, and XX which lacks expression of these fibers. All three genotypes were identified among participants. Distribution of these genotypes was significant them, and it is noticeable that XX genotype was less in numbers than the other genotypes. BMI and BFP were in acceptable limits in athletes, but it was found to increase in control group with age. Two males and one female exhibited odd reading regarding muscle mass and testosterone level which was significantly higher than the others. Genetic analysis of these athletes showed SNPs that altered ORFs reading site, and production of different protein from the gene which affected muscle mass dramatically toward higher density, and triggered higher testosterone level in the body as an exceled response to intensive training. The three of them were found to be of XX genotype. Among athletic participants, physical fitness was high especially with young athletes. Most sprinters were found to be RR and RX genotype, while endurance athletes were of XX genotype. Significant SNPs at actin3 gene determined exceled athletes who were found to comprise less than 1%.

A molecular insight in sport and athletic alpha – actin3 gene in students of Physical Education Faculty and bodybuilders.

Alpha – actin3 is gene for athletic performance and sport. Three types of genotypes were identified within the gene: RR homozygous, RX heterozygous, and XX which lacks expression of these fibers. All three genotypes were identified among participants. Distribution of these genotypes was significant them, and it is noticeable that XX genotype was less in numbers than the other genotypes. BMI and BFP were in acceptable limits in athletes, but it was found to increase in control group with age. Two males and one female exhibited odd reading regarding muscle mass and testosterone level which was significantly higher than the others. Genetic analysis of these athletes showed SNPs that altered ORFs reading site, and production of different protein from the gene which affected muscle mass dramatically toward higher density, and triggered higher testosterone level in the body as an exceled response to intensive training. The three of them were found to be of XX genotype. Among athletic participants, physical fitness was high especially with young athletes. Most sprinters were found to be RR and RX genotype, while endurance athletes were of XX genotype. Significant SNPs at actin3 gene determined exceled athletes who were found to comprise less than 1%.

The ACTN3 R577Xgth in Korea national combat athletes

The aim of the present study is the investigation of the association between the ACTN3 genotype and the grip strength according to measurements in Korea National combats athletes. Fifty-six Korea National combats athletes (Judo and wrestling, male = 38, female = 18) and two hundred and twenty-one control group of normal populations (male = 135, female = 86) were recruited for the present study. The variables under examination were body composition, Wingate anaerobic test, and handgrip strength. Genotyping for the ACTN3 (rs 1815739) polymorphism was performed using the TaqMan approach. ACTN3 gene distribution of subjects was in the Hardy–Weinberg equilibrium (athletes: P = 0.175; control: P = 0.508). The relative power drop ( P = 0.041) differed significantly among the ACTN3 genotypes, and non-significant differences in peak power and average power. The relative left hand grip strength in male ( P = 0.004) differed significantly between the ACTN3 R allele. However, non-significant differences right hand grip strength in male and both hand grip strength in female. We found a positive relationship between the ACTN3 R577X genotypes and the relative left hand grip strength in male Korean National combat athletes. Our data indicate that the ACTN3 R allele (RR and RX genotypes) is associated with muscle strength output capacity. Le but de la présente étude est l’investigation de l’association entre le génotype ACTN3 et la force de préhension selon des mesures en Corée national combat des athlètes. Cinquante-six athlètes de combat nationaux de Corée (judo et lutte, hommes = 38, femmes = 18) et deux cent vingt et un groupes témoin de populations normales (hommes = 135, femmes = 86) ont été recrutés pour la présente étude. Les variables examinées étaient la composition corporelle, le test anaérobie Wingate et la force de la poignée. Le génotypage du polymorphisme ACTN3 (rs 1815739) a été réalisé en utilisant l’approche TaqMan. La distribution du gène ACTN3 des sujets était dans l’équilibre Hardy–Weinberg (athlètes : p = 0,175 ; contrôle : p = 0,508). La chute de puissance relative ( p = 0,041) différait significativement entre les génotypes ACTN3, et pas de différences significatives de puissance de crête et de puissance moyenne. La force de préhension relative de la main gauche chez l’homme ( p = 0,004) différait significativement entre l’allèle ACTN3 R. Cependant, il n’y a pas de différences significatives entre la force de préhension de la main droite chez l’homme et la force de préhension de la main chez la femme. Nous avons trouvé une relation positive entre les génotypes ACTN3 R577X et la force de préhension relative de la main gauche chez les athlètes masculins de combat national coréen. Nos données indiquent que l’allèle ACTN3 R (génotypes RR et RX) est associé à la capacité de sortie de force musculaire.

Muscular Strength and Quality of Life in Older Adults: The Role of ACTN3 R577X Polymorphism.

As longevity is increasing, the 65-year-old and older population is projected to increase in the next decades, as are the consequences of age-related muscle deterioration on the quality of life. The purpose of this study was to examine the associations of the ACTN3 R577X polymorphism with quality of life and muscular strength in an older Spanish population. In total, 281 older adults participated in this study. Anthropometric measurements, chronic diseases, prescribed medications, quality of life, hand grip strength, and physical activity and nutritional status data were collected. ACTN3 R577X genotyping was determined using Taqman probes. Multivariate regression analysis revealed in adjusted model that, in men, the ACTN3 R577X genotype was significantly associated with hand grip strength (HGS), regression coefficient (β) = 1.23, p = 0.008, dimension 1 of the five-dimension questionnaire EuroQoL (EQ-5D, mobility), (β) = −1.44, p = 0.006, and clinical group risk (CGR) category (β) = −1.38, p = 0.006. In women, a marginal association between the ACTN3 R577X genotype and the CGR category was observed, with a regression coefficient of (β) = −0.97, (p = 0.024). Our findings suggest that the ACTN3 R577X genotype may influence the decline in muscle strength and quality of life in older Spanish adult males.

Effect of ACTN3 R577X Genotype on Injury Epidemiology in Elite Endurance Runners.

The p.R577X polymorphism (rs1815739) in the ACTN3 gene causes individuals with the ACTN3 XX genotype to be deficient in functional α-actinin-3. Previous investigations have found that XX athletes are more prone to suffer non-contact muscle injuries. This investigation aimed to determine the influence of the ACTN3 R577X polymorphism in the injury epidemiology of elite endurance athletes. Using a cross-sectional experiment, the epidemiology of running-related injuries was recorded for one season in a group of 89 Spanish elite endurance runners. ACTN3 R577X genotype was obtained for each athlete using genomic DNA samples. From the study sample, 42.7% of athletes had the RR genotype, 39.3% had the RX genotype, and 18.0% had the XX genotype. A total of 96 injuries were recorded in 57 athletes. Injury incidence was higher in RR runners (3.2 injuries/1000 h of running) than in RX (2.0 injuries/1000 h) and XX (2.2 injuries/1000 h; p = 0.030) runners. RR runners had a higher proportion of injuries located in the Achilles tendon, RX runners had a higher proportion of injuries located in the knee, and XX runners had a higher proportion of injuries located in the groin (p = 0.025). The ACTN3 genotype did not affect the mode of onset, the severity, or the type of injury. The ACTN3 genotype slightly affected the injury epidemiology of elite endurance athletes with a higher injury rate in RR athletes and differences in injury location. However, elite ACTN3 XX endurance runners were not more prone to muscle-type injuries.

Is ACTN3 R577X Genotype Associated with a Preference in Type of Exercise Such as Sprint or Endurance?

The purpose of this study was to determine whether genotypes in the α-actinin-3 gene are associated with preferences in the type of exercise (sprint vs. endurance) in male college students. The study enrolled 64 healthy male students aged 18-21 years old, excluding elite athletes. DNA was extracted from the subjects’ hair samples to determine the genotypes of the α-actinin-3 gene, whereas a simple questionnaire was used to investigate preference in the type of exercise. In summary, 35.5% of subjects with the RR and RX types (R-allele group) preferred sprint, whereas 47.3% of subjects with the XX type preferred endurance. Furthermore, 53.3% of the R-allele group and 31.6% of the XX group preferred endurance and sprint, respectively. This implies that the inconsistency (or mismatch) between muscle functional properties, which are characterized by genotypes and preference in type of exercise, tends to be greater in the R-allele group than in the XX type. In conclusion, the genotypes of α-actinin-3 did not play a significant role in deciding the preference in type of exercise. It can also be suspected that the mismatch between muscle functional properties and exercise preference is influenced by the daily life of students who are not exposed to high-intensity exercise stimuli.