Genetic predictors of match performance in sub-elite Australian football players: A pilot study

The current study aimed to determine whether previously identified candidate polymorphisms were associated with match performance in sub-elite Australian Rules Football (ARF) players. The genotypes of thirty players were analysed along with 3x1-kilometre time trial results, ARF-specific skill assessments (handball and kicking), and match performance (direct game involvements) per minute (DGIs/min) to investigate if there was a relationship between any of the variables. Results support previous findings that aerobic time trials are a significant predictor of DGIs/min in sub-elite ARF players. Significant associations were found for genotypes ADRB2 CC (p = .001), PPARGC1A AA (p = .001), PPARGC1A AG (p \u3c .001), ACE ID (p \u3c .001), COMT AA (p = .003), BDNF AG (p = .008), ADRB1 CC (p = .018) and ADRB3 CC (p = .010) and the 3x1-kilometre time trials (p \u3c .001). In the current study, a variant in the DRD2 gene was a strong predictor of handball possessions during a match. Significance was seen for variants in the BDNF and COMTgenes when the kicking and handball skill test results were combined and used in a linear mixed model to predict DGIs/min, suggesting a potential relationship with motor learning. The confirmation of genetic predictors of player performance in a team sport, such as ARF, suggests a portion of the physiological mechanisms of skill and ARF-specific talent may be explained by the expression of a specific number of genes

The potential role of genetic markers in talent identification and athlete assessment in elite sport

In elite sporting codes, the identification and promotion of future athletes into specialized talent pathways is heavily reliant upon objective physical, technical, and tactical characteristics, in addition to subjective coach assessments. Despite the availability of a plethora of assessments, the dependence on subjective forms of identification remain commonplace in most sporting codes. More recently, genetic markers, including several single nucleotide polymorphisms (SNPs), have been correlated with enhanced aerobic capacity, strength, and an overall increase in athletic ability. In this review, we discuss the effects of a number of candidate genes on athletic performance, across single-skilled and multifaceted sporting codes, and propose additional markers for the identification of motor skill acquisition and learning. While displaying some inconsistencies, both the ACE and ACTN3 polymorphisms appear to be more prevalent in strength and endurance sporting teams, and have been found to correlate to physical assessments. More recently, a number of polymorphisms reportedly correlating to athlete performance have gained attention, however inconsistent research design and varying sports make it difficult to ascertain the relevance to the wider sporting population. In elucidating the role of genetic markers in athleticism, existing talent identification protocols may significantly improve—and ultimately enable—targeted resourcing in junior talent pathways

Literature Review: Anthropometric, strength and physical capacities of senior and junior Australian footballers

This study demonstrates that senior Australian Football players are heavier and possess superior strength characteristics without any meaningful difference in aerobic capacities when compared to under 18 players. The aim of this study was to compare the anthropometric and physical characteristics of state based junior and senior Australian Football (AF) players. Thirty-One League (age 23.7 ± 2.6 years), 19 Development League (DL) (age 20.5 ± 1.9 years), and 34 Under 18 (U18) players (age 17.4 ± 0.7 years) were recruited from a single AF club. Assessments included height and mass, upper body (bench press and weighted pull-up) and lower body (squat) three repetition max strength, lower body power (vertical jump) and 3 x 1-kilometre time trial. Multivariate analysis with Bonferroni post hoc tests were used to examine the differences between grades and position. Cohen’s d statistic was used to assess the magnitude of difference. Significant age and body mass differences were evident between all three grades (p\u3c0.01) and large to moderate differences were evident between League and U18 players in the absolute and relative bench press and back squat characteristics. No significant difference between time trial performance was evident between grades. The results demonstrate a particular need to ensure programs develop both absolute and relative strength in younger players to prepare them to compete safely and successfully in senior competitions

A Veritable Menagerie of Heritable Bacteria from Ants, Butterflies, and Beyond: Broad Molecular Surveys and a Systematic Review

Maternally transmitted bacteria have been important players in the evolution of insects and other arthropods, affecting their nutrition, defense, development, and reproduction. Wolbachia are the best studied among these and typically the most prevalent. While several other bacteria have independently evolved a heritable lifestyle, less is known about their host ranges. Moreover, most groups of insects have not had their heritable microflora systematically surveyed across a broad range of their taxonomic diversity. To help remedy these shortcomings we used diagnostic PCR to screen for five groups of heritable symbionts—Arsenophonus spp., Cardinium hertigii, Hamiltonella defensa, Spiroplasma spp., and Wolbachia spp.—across the ants and lepidopterans (focusing, in the latter case, on two butterfly families—the Lycaenidae and Nymphalidae). We did not detect Cardinium or Hamiltonella in any host. Wolbachia were the most widespread, while Spiroplasma (ants and lepidopterans) and Arsenophonus (ants only) were present at low levels. Co-infections with different Wolbachia strains appeared especially common in ants and less so in lepidopterans. While no additional facultative heritable symbionts were found among ants using universal bacterial primers, microbes related to heritable enteric bacteria were detected in several hosts. In summary, our findings show that Wolbachia are the dominant heritable symbionts of ants and at least some lepidopterans. However, a systematic review of symbiont frequencies across host taxa revealed that this is not always the case across other arthropods. Furthermore, comparisons of symbiont frequencies revealed that the prevalence of Wolbachia and other heritable symbionts varies substantially across lower-level arthropod taxa. We discuss the correlates, potential causes, and implications of these patterns, providing hypotheses on host attributes that may shape the distributions of these influential bacteria.Organismic and Evolutionary Biolog

Genetic variants within NOGGIN, COL1A1, COL5A1, and IGF2 are associated with musculoskeletal injuries in elite male Australian football league players: A preliminary study

Introduction: Australian Football is a dynamic team sport that requires many athletic traits to succeed. Due to this combination of traits, as well as technical skill and physicality, there are many types of injuries that could occur. Injuries are not only a hindrance to the individual player, but to the team as a whole. Many strength and conditioning personnel strive to minimise injuries to players to accomplish team success. Purpose: To investigate whether selected polymorphisms have an association with injury occurrence in elite male Australian Football players. Methods: Using DNA obtained from 46 elite male players, we investigated the associations of injury-related polymorphisms across multiple genes (ACTN3, CCL2, COL1A1, COL5A1, COL12A1, EMILIN1, IGF2, NOGGIN, SMAD6) with injury incidence, severity, type (contact and non-contact), and tissue (muscle, bone, tendon, ligament) over 7 years in one Australian Football League team. Results: A significant association was observed between the rs1372857 variant in NOGGIN (p = 0.023) and the number of total muscle injuries, with carriers of the GG genotype having a higher estimated number of injuries, and moderate, or combined moderate and high severity rated total muscle injuries. The COL5A1 rs12722TT genotype also had a significant association (p = 0.028) with the number of total muscle injuries. The COL5A1 variant also had a significant association with contact bone injuries (p = 0.030), with a significant association being found with moderate rated injuries. The IGF2 rs3213221-CC variant was significantly associated with a higher estimated number of contact tendon injuries per game (p = 0.028), while a higher estimated number of total ligament (p = 0.019) and non-contact ligament (p = 0.002) injuries per game were significantly associated with carriage of the COL1A1 rs1800012-TT genotype. Conclusions: Our preliminary study is the first to examine associations between genetic variants and injury in Australian Football. NOGGIN rs1372857-GG, COL5A1 rs12722-TT, IGF2 rs3213221-CC, and COL1A1 rs1800012-TT genotypes held various associations with muscle-, bone-, tendon- and ligament-related injuries of differing severities. To further increase our understanding of these, and other, genetic variant associations with injury, competition-wide AFL studies that use more players and a larger array of gene candidates is essential

Genetic associations with athlete performance and injury susceptibility in elite Australian football

Australian Football is a dynamic team sport involving a combination of physical capabilities such as endurance, strength and power. Similar to other football codes, selection into elite Australian Football teams is predominantly associated with a player’s performance in physical and technical skill assessments, as well as their performance during matches. In contrast to other sporting codes, there are no studies exploring a potential genetic association towards success in Australian Football. Moreover, no studies have explored genetic associations of skill-based performance, injury risk, and athletic performance in Australian Football players. Recently, there has been an increased focus on the genetic contribution to athleticism, which has focused on understanding the causes of player variability. To investigate this concept in Australian Football further, the aims of this thesis were to 1) examine the genetic profile of elite Australian Football players using a group of selected candidate genes; 2) investigate the relationship between cardiovascular performance and genotypes of selected genes; 3) explore the occurrence and severity of injuries in Australian Football and their possible relationship to injury-related genes and their genotypes; and 4) examine if there is a relationship between time to injury, genetic polymorphisms and strength. Study one found that the ACTN3 rs1815739-XX genotype was significantly underrepresented, and the R allele was significantly overrepresentation in elite Australian Footballers compared to healthy controls. Study two found that the ADRB1 (rs18011253) and PPARGC1a (rs8192678) genes showed significant results, in particular the Arg389Gly CC and Gly482Ser GG genotypes of their respective genes, with both genotypes associated with faster two-kilometre time trial results in the studied population. Study three found that the NOGGIN rs1372857-GG and COL5A1 rs1372857-TT genotypes were significantly associated with a higher number of estimated muscle related injuries, with the NOGGIN rs1372857-GG having an association to higher severity (moderate and high rated) of injuries. In addition, the COL5A1 rs1372857-TT genotype was also associated with bone related injuries, with an association to moderate severity rated injuries. The CC genotype of the IGF2 (rs3213221) polymorphism had a higher number of tendon related injuries, with a further association towards low severity (low rated) injuries. The COL1A1 rs-1800012-TT genotype was related to a higher estimated number of ligament related injuries with a significant association to lower severity injuries. Significant results were found in study four regarding significant association between the COL12A1 rs970547-TC genotype and an increased risk to first upper body injury compared to the TT genotype of 167.2%. The IMTP had significant results with all its variables (peak force, and relative peak force (N.kg-1 and N)) for any musculoskeletal injuries, upper body musculoskeletal injuries and non-contact upper body musculoskeletal injuries. No associations were discovered for the NordBord eccentric hamstring strength test or the 2-kilometre time trial. This scientific approach could be replicated in a larger population, i.e., the entire Australian Football League, to establish if certain genotypes or alleles are related to an earlier occurrence of injuries. This doctoral thesis provides preliminary research into understanding the links between genes and athlete’s performance and injury of elite Australian Football players. This may lead to further research to develop this knowledge, which may in the long term assist in developing targeted training programs to achieve better outcomes for both the individual athletes and their sporting organisation. Future research could be expanded to all Australian Football League teams providing a greater sample size to determine the genetic variants that predict an elite Australian Footballer player and team. Tactical and High-Performance Coaches could use this information to understand training effects on players to hone in on individual strengths and weaknesses to ideally produce a more cohesive teams without many injuries or changes throughout a season

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

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

Abstract: 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.</p

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

ACTN3 (R577X) genotype is associated with Australian football league players

Jacob, Y, Hart, NH, Cochrane, JL, Spiteri, T, Laws, SM, Jones, A, Rogalski, B, Kenna, J, and Anderton, RS. ACTN3 (R577X) genotype is associated with Australian Football League players. J Strength Cond Res XX(X): 000–000, 2020—Genetic variants in the angiotensin-converting enzyme (ACE) and alpha actinin-3 (ACTN3) genes have been associated with elite sport athletic performance. This study aimed to investigate the frequency of each polymorphism in a cohort of elite Australian football (AF) players. To achieve this, 47 players from an Australian Football League (AFL) club and 59 healthy age matched controls with no history of elite sporting competition were recruited for this study. Each subject provided saliva samples through buccal swab for DNA extraction and genotyping, with group comparisons made using χ2 and odds ratio analysis. There was no significant difference in ACE I/D genotype between healthy control and elite AF players. The ACTN3 XX genotype was significantly underrepresented in AFL players (4.3%) compared with healthy controls (28.8%, p = 0.003). In addition, there was a greater representation of the R allele in elite AF players (70.2%) when compared with healthy controls (50%; χ2 = 8.834, p = 0.002). This is the first study to investigate genetic variants in elite AF players, with results suggesting that the ACTN3 gene may play a significant role explaining aspects of athletic performance in AF