DoPPARGC1AandPPARαpolymorphisms influence sprint or endurance phenotypes?

The PPARGC1A Gly482Ser polymorphism is associated with elite long-distance running performance

Success in long-distance running relies on multiple factors including oxygen utilisation and lactate metabolism, and genetic associations with athlete status suggest elite competitors are heritably predisposed to superior performance. The Gly allele of the PPARGC1A Gly482Ser rs8192678 polymorphism has been associated with endurance athlete status and favourable aerobic training adaptations. However, the association of this polymorphism with performance amongst long-distance runners remains unclear. Accordingly, this study investigated whether rs8192678 was associated with elite status and competitive performance of long-distance runners. Genomic DNA from 656 Caucasian participants including 288 long-distance runners (201 men, 87 women) and 368 non-athletes (285 men, 83 women) was analysed. Medians of the 10 best UK times (Top10) for 10 km, half-marathon and marathon races were calculated, with all included athletes having personal best (PB) performances within 20% of Top10 (this study's definition of "elite"). Genotype and allele frequencies were compared between athletes and non-athletes, and athlete PB compared between genotypes. There were no differences in genotype frequency between athletes and non-athletes, but athlete Ser allele carriers were 2.5% faster than Gly/Gly homozygotes (p = 0.030). This study demonstrates that performance differences between elite long-distance runners are associated with rs8192678 genotype, with the Ser allele appearing to enhance performance.

An Association Between FNDC5, PGC-1α Genetic Variants and Obesity in Chinese Children: A Case-Control Study

BACKGROUND

Fibronectin type III domain containing protein 5 (FNDC5) gene encodes irisin that regulates adipose tissue metabolism. Peroxide-proliferator-activated receptor γ coactivator 1α (PGC-1α) is a powerful promoter of mitochondrial biosynthesis and oxidative metabolism, which plays an important role in inducing heat production and energy consumption of brown fat. PGC1-α expression stimulated an increase in expression of FNDC5.

PURPOSE

The aims of this study were to analyze the association between FNDC5, PGC-1α genetic variants and overweight or obesity in Chinese children and adolescents.

METHODS

A total of 198 children and adolescents with overweight or obesity and 198 children and adolescents with normal weight were screened according to gender and age 1:1. The healthy eating behaviors, moderate-to-vigorous physical activity time were surveyed using food frequency questionnaire and CLASS questionnaire, respectively. Genotypes of FNDC5 and PGC-1α gene were detected using SNaPshot method.

RESULTS

GT genotype of FNDC5 (rs16835198) increased the risk of overweight or obesity in boys (OR (95% CI): 1.68 (1.00, 2.93)) based on overdominant model; GG genotype of FNDC5 (rs16835198) decreased the risk of overweight or obesity in girls and boys (OR (95% CI): 0.45 (0.21,0.97), 0.45 (0.24, 0.83), respectively) based on dominant model; TT genotype of FNDC5 (rs16835198) increased the risk of overweight or obesity in girls based on recessive model (OR (95% CI): 2.46 (1.19, 5.05)), and based on the additive model (OR (95% CI): 3.82 (1.49, 9.80)). There was significant interaction between FNDC5 (rs16835198) and PGC-1α (rs3755863, rs8192678), healthy eating behaviors, moderate-to-vigorous physical activity time, interaction between PGC-1α (rs8192678) and moderate-to-vigorous physical activity time in the occurrence of overweight or obesity in Chinese children and adolescents.

CONCLUSION

FNDC5 (rs16835198) played an independent or interactive role with PGC-1α (rs3755863, rs8192678), healthy eating behaviors, moderate-to-vigorous physical activity time in the occurrence of overweight or obesity in Chinese children and adolescents.

The Influence of the Differentiation of Genes Encoding Peroxisome Proliferator-Activated Receptors and Their Coactivators on Nutrient and Energy Metabolism

Genetic components may play an important role in the regulation of nutrient and energy metabolism. In the presence of specific genetic variants, metabolic dysregulation may occur, especially in relation to the processes of digestion, assimilation, and the physiological utilization of nutrients supplied to the body, as well as the regulation of various metabolic pathways and the balance of metabolic changes, which may consequently affect the effectiveness of applied reduction diets and weight loss after training. There are many well-documented studies showing that the presence of certain polymorphic variants in some genes can be associated with specific changes in nutrient and energy metabolism, and consequently, with more or less desirable effects of applied caloric reduction and/or exercise intervention. This systematic review focused on the role of genes encoding peroxisome proliferator-activated receptors (PPARs) and their coactivators in nutrient and energy metabolism. The literature review prepared showed that there is a link between the presence of specific alleles described at different polymorphic points in PPAR genes and various human body characteristics that are crucial for the efficacy of nutritional and/or exercise interventions. Genetic analysis can be a valuable element that complements the work of a dietitian or trainer, allowing for the planning of a personalized diet or training that makes the best use of the innate metabolic characteristics of the person who is the subject of their interventions.

Genetics of long-distance runners and road cyclists-A systematic review with meta-analysis

The aim of this systematic review and meta-analysis was to identify the genetic variants of (inter)national competing long-distance runners and road cyclists compared with controls. The Medline and Embase databases were searched until 15 November 2021. Eligible articles included genetic epidemiological studies published in English. A homogenous group of endurance athletes competing at (inter)national level and sedentary controls were included. Pooled odds ratios based on the genotype frequency with corresponding 95% confidence intervals (95%CI) were calculated using random effects models. Heterogeneity was addressed by Q-statistics, and I² . Sources of heterogeneity were examined by meta-regression and risk of bias was assessed with the Clark Baudouin scale. This systematic review comprised of 43 studies including a total of 3938 athletes and 10 752 controls in the pooled analysis. Of the 42 identified genetic variants, 13 were investigated in independent studies. Significant associations were found for five polymorphisms. Pooled odds ratio [95%CI] favoring athletes compared with controls was 1.42 [1.12-1.81] for ACE II (I/D), 1.66 [1.26-2.19] for ACTN3 TT (rs1815739), 1.75 [1.34-2.29] for PPARGC1A GG (rs8192678), 2.23 [1.42-3.51] for AMPD1 CC (rs17602729), and 2.85 [1.27-6.39] for HFE GG + CG (rs1799945). Risk of bias was low in 25 (58%) and unclear in 18 (42%) articles. Heterogeneity of the results was low (0%-20%) except for HFE (71%), GNB3 (80%), and NOS3 (76%). (Inter)national competing runners and cyclists have a higher probability to carry specific genetic variants compared with controls. This study confirms that (inter)national competing endurance athletes constitute a unique genetic make-up, which likely contributes to their performance level.

Prediction and Identification of Power Performance Using Polygenic Models of Three Single-Nucleotide Polymorphisms in Chinese Elite Athletes

Objective: The manuscript aims to explore the relationship between power performance and SNPs of Chinese elite athletes and to create polygenic models.

Methods: One hundred three Chinese elite athletes were divided into the power group (n = 60) and endurance group (n = 43) by their sports event. Best standing long jump (SLJ) and standing vertical jump (SVJ) were collected. Twenty SNPs were genotyped by SNaPshot. Genotype distribution and allele frequency were compared between groups. Additional genotype data of 125 Chinese elite athletes were used to verify the screened SNPs. Predictive and identifying models were established by multivariate logistic regression analysis.

Results: ACTN3 (rs1815739), ADRB3 (rs4994), CNTFR (rs2070802), and PPARGC1A (rs8192678) were significantly different in genotype distribution or allele frequency between groups (p < 0.05). The predictive model consisted of ACTN3 (rs1815739), ADRB3 (rs4994), and PPARGC1A (rs8192678), the area under curve (AUC) of which was 0.736. The identifying model consisted of body mass index (BMI), standing vertical jump (SVJ), ACTN3, ADRB3, and PPARGC1A, the area under curve (AUC) of which was 0.854. Based on the two models, nomograms were created to visualize the results.

Conclusion: Two models can be used for talent identification in Chinese athletes, among which the predictive model can be used in adolescent athletes to predict development potential of power performance and the identifying one can be used in elite athletes to evaluate power athletic status. These can be applied quickly and visually by using nomograms. When the score is more than the 130 or 148 cutoff, it suggests that the athlete has a good development potential or a high level for power performance.

PPARα Gene Is Involved in Body Composition Variation in Response to an Aerobic Training Program in Overweight/Obese

The objective of this study was to investigate the relationship of the polymorphism in Intron 7 G/C (rs 4253778) of the peroxisome proliferator-activated receptor alpha (PPARα) gene with the magnitude of changes in the body composition of an overweight and obese population that underwent an aerobic training program. Fifty-eight previously inactive men and women, body mass index (BMI) 31.5 ± 2.8 kg/m², 46.5% (n = 27) genotyped as CC genotype and 53.5% (n = 31) as CA+AA, underwent a 12-week aerobic training (walking/running). Aerobic capacity (ergospirometry), body composition (DXA), and nutritional assessment were made before and 48 h after the experimental protocol. Two-way ANOVA, chi-square test, and logistic regression were used (p < 0.05). Twenty-seven volunteers (46.5%) were identified as CC genotype and 31 (53.5%) as CA+AA genotype. Time-group interaction showed that there was no difference in these between two allele groups. However, differences in distribution of respondents or nonresponders according to allele A were identified for fat mass (p ≤ 0.003), percentage fat mass (p ≤ 0.002), the waist (p ≤ 0.009), abdomen (p ≤ 0.000), and hip (p ≤ 0.001), this difference being independent for the fat mass. Meanwhile, sex, age, and nutritional management have also been found to be influential factors. It is concluded that the PPARα gene is involved in varying body composition in response to an aerobic training program.

Does the PPARA Intron 7 Gene Variant (rs4253778) Influence Performance in Power/Strength-Oriented Athletes? A Case-Control Replication Study in Three Cohorts of European Gymnasts

Athletic ability is influenced by several exogenous and endogenous factors including genetic component. Hundreds of gene variants have been proposed as potential genetic markers associated with fitness-related phenotypes as well as elite-level athletic performance. Among others, variants within the PPARA gene that code for the peroxisome proliferator activated receptor α are of potential interest. The main goal of the present study was to determine PPARA (G/C, rs4253778) genotype distribution among a group of Polish, Lithuanian and Italian international level male gymnasts and to compare our findings with those of previous research on the frequency of the PPARA intron 7 C allele/CC genotype in power/strength-oriented athletes. A total of 464 male subjects (147 gymnasts and 317 controls) from Poland (n = 203), Italy (n = 146) and Lithuania (n = 107) participated in the study. No statistically significant differences were found in any of the analyzed cohorts. However, a significantly higher frequency of the CC genotype of the PPARA rs4253778 polymorphism was observed when all gymnasts were pooled and compared with pooled control using a recessive model of inheritance (OR = 3.33, 95% CI = 1.18-10, p = 0.022). It is important to know that we investigated a relatively small sample of male European gymnasts and our results are limited only to male participants. Thus, it is necessary to validate our results in larger cohorts of athletes of different ethnicities and also in female gymnasts to find out whether there is a gender effect.

A meta-analysis on the association of ACE and PPARA gene variants and endurance athletic status

BACKGROUND

Genetics has an important role in determining the athletic ability and endurance performance potential. This study aimed to investigate the variable results obtained from endurance athletes and control participants in terms of angiotensin-converting enzyme (ACE) and peroxisome proliferator-activated receptor alpha (PPARA) polymorphism distributions.

METHODS

Multiple electronic databases were investigated independently by two researchers. A meta-analysis was conducted on the association of ACE insertion/deletion (I/D) polymorphism and PPARA G/C polymorphisms with endurance athletes. Odds ratios (OR) and 95% confidence intervals (CI) were estimated. Twenty-six studies were identified for the ACE I/D for 2979 endurance athletes and 10048 control participants while seven studies were identified for PPARA G/C for 901 endurance athletes and 2292 control participants.

RESULTS

There was a significant difference in ACE genotype distribution between endurance athletes and control (II vs. ID+DD: OR=1.48; 95% CI=0.30-2.67; p=0.001). On the other hand, there was no a significant difference in PPARA G/C polymorphism genotype distribution between endurance athletes and control (GC+CC vs. GG: OR=0.93; 95% CI=-0.46-2.32; p=0.192; GC+GG vs CC: OR=0.62; 95% CI=-1.75-2.99; p=0.604).

CONCLUSIONS

The results have shown that ACE I/D polymorphism may be associated with endurance performance in sports and that the predominance of the ACE II genotype in a person may play an advantageous role in being an endurance athlete. However, this effect has not been observed in PPARA G/C polymorphism.

Associations among perfluorooctanesulfonic/perfluorooctanoic acid levels, nuclear receptor gene polymorphisms, and lipid levels in pregnant women in the Hokkaido study

The effect of interactions between perfluorooctanesulfonic (PFOS)/perfluorooctanoic acid (PFOA) levels and nuclear receptor genotypes on fatty acid (FA) levels, including those of triglycerides, is not clear understood. Therefore, in the present study, we aimed to analyse the association of PFOS/PFOA levels and single-nucleotide polymorphisms (SNPs) in nuclear receptors with FA levels in pregnant women. We analysed 504 mothers in a birth cohort between 2002 and 2005 in Japan. Serum PFOS/PFOA and FA levels were measured using liquid chromatography-tandem mass spectrometry and gas chromatography-mass spectrometry. Maternal genotypes in PPARA (rs1800234; rs135561), PPARG (rs3856806), PPARGC1A (rs2970847; rs8192678), PPARD (rs1053049; rs2267668), CAR (rs2307424; rs2501873), LXRA (rs2279238) and LXRB (rs1405655; rs2303044; rs4802703) were analysed. When gene-environment interaction was considered, PFOS exposure (log₁₀ scale) decreased palmitic, palmitoleic, and oleic acid levels (log₁₀ scale), with the observed β in the range of - 0.452 to - 0.244; PPARGC1A (rs8192678) and PPARD (rs1053049; rs2267668) genotypes decreased triglyceride, palmitic, palmitoleic, and oleic acid levels, with the observed β in the range of - 0.266 to - 0.176. Interactions between PFOS exposure and SNPs were significant for palmitic acid (P_int = 0.004 to 0.017). In conclusion, the interactions between maternal PFOS levels and PPARGC1A or PPARD may modify maternal FA levels.

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.

Short-Term, Combined Fasting and Exercise Improves Body Composition in Healthy Males

Fasting enhances the beneficial metabolic outcomes of exercise; however, it is unknown whether body composition is favorably modified on the short term. A baseline-follow-up study was carried out to assess the effect of an established protocol involving short-term combined exercise with fasting on body composition. One hundred seven recreationally exercising males underwent a 10-day intervention across 15 fitness centers in the Netherlands involving a 3-day gradual decrease of food intake, a 3-day period with extremely low caloric intake, and a gradual 4-day increase to initial caloric intake, with daily 30-min submaximal cycling. Using dual-energy X-ray absorptiometry analysis, all subjects substantially lost total body mass (-3.9 ± 1.9 kg; p < .001) and fat mass (-3.3 ± 1.3 kg; p < .001). Average lean mass was lost (-0.6 ± 1.5 kg; p < .001), but lean mass as a percentage of total body mass was not reduced. The authors observed a loss of -3.9 ± 1.9% android fat over total fat mass (p < .001), a loss of -2.2 ± 1.9% gynoid over total fat mass (p < .001), and reduced android/gynoid ratios (-0.05 ± 0.1; p < .001). Analyzing 15 preselected single-nucleotide polymorphisms in 13 metabolism-related genes revealed trending associations for thyroid state-related single-nucleotide polymorphisms rs225014 (deiodinase 2) and rs35767 (insulin-like growth factor1), and rs1053049 (PPARD). In conclusion, a short period of combined fasting and exercise leads to a substantial loss of body and fat mass without a loss of lean mass as a percentage of total mass.

A Potential Endurance Algorithm Prediction in the Field of Sports Performance

Sport performance is influenced by several factors, including genetic susceptibility. In the past years, specific single nucleotide polymorphisms have been associated to sport performance; however, these effects should be considered in multivariable prediction systems since they are related to a polygenic inheritance. The aim of this study was to design a genetic endurance prediction score (GES) of endurance performance and analyze its association with anthropometric, nutritional and sport efficiency variables in a cross-sectional study within fifteen male cyclists. A statistically significant positive relationship between GES and the VO₂ maximum (P = 0.033), VO₂ VT1 (P = 0.049) and VO₂ VT2 (P < 0.001) was observed. Moreover, additional remarkable associations between genotype and the anthropometric, nutritional and sport performance variables, were achieved. In addition, an interesting link between the habit of consuming caffeinated beverages and the GES was observed. The outcomes of the present study indicate a potential use of this genetic prediction algorithm in the sports' field, which may facilitate the finding of genetically talented athletes, improve their training and food habits, as well as help in the improvement of physical conditions of amateurs.

PPARGC1A rs8192678 and NRF1 rs6949152 Polymorphisms Are Associated with Muscle Fiber Composition in Women

PPARGC1A rs8192678 G/A (Gly482Ser) and NRF1 rs6949152 A/G polymorphisms have been associated with endurance athlete status, endurance performance phenotypes, and certain health-related markers of different pathologies such as metabolic syndrome, diabetes, and dyslipidemia. We hypothesized that they could be considered interesting candidates for explaining inter-individual variations in muscle fiber composition in humans. We aimed to examine possible associations of these polymorphisms with myosin heavy-chain (MHC) isoforms as markers of muscle fiber compositions in vastus lateralis muscle in a population of 214 healthy Japanese subjects, aged between 19 and 79 years. No significant associations were found in men for any measured variables. In contrast, in women, the PPARGC1A rs8192678 A/A genotype was significantly associated with a higher proportion of MHC-I (p = 0.042) and with a lower proportion of MHC-IIx (p = 0.033), and the NRF1 rs6949152 AA genotype was significantly associated with a higher proportion of MHC-I (p = 0.008) and with a lower proportion of MHC IIx (p = 0.035). In women, the genotype scores of the modes presenting the most significant results for PPARGC1A rs8192678 G/A (Gly482Ser) and NRF1 rs6949152 A/G polymorphisms were significantly associated with MHC-I (p = 0.0007) and MHC IIx (p = 0.0016). That is, women with combined PPARGC1A A/A and NRF1 A/A genotypes presented the highest proportion of MHC-I and the lowest proportion of MHC-IIx, in contrast to women with combined PPARGC1A GG+GA and NRF1 AG+GG genotypes, who presented the lowest proportion of MHC-I and the highest proportion of MHC-IIx. Our results suggest possible associations between these polymorphisms (both individually and in combination) and the inter-individual variability observed in muscle fiber composition in women, but not in men.

Association of Elite Sports Status with Gene Variants of Peroxisome Proliferator Activated Receptors and Their Transcriptional Coactivator

BACKGROUND

Although the scientific literature regarding sports genomics has grown during the last decade, some genes, such as peroxisome proliferator activated receptors (PPARs), have not been fully described in terms of their role in achieving extraordinary sports performance. Therefore, the purpose of this systematic review was to determine which elite sports performance constraints are positively influenced by PPARs and their coactivators.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were used, with a combination of PPAR and sports keywords.

RESULTS

In total, 27 studies that referred to PPARs in elite athletes were included, where the Ala allele in PPARG rs1801282 was associated with strength and power elite athlete status in comparison to subelite athlete status. The C allele in PPARA rs4253778 was associated with soccer, and the G allele PPARA rs4253778 was associated with endurance elite athlete status. Other elite status endurance alleles were the Gly allele in PPARGC1A rs8192678 and the C allele PPARD rs2016520.

CONCLUSIONS

PPARs can be used for estimating the potential to achieve elite status in human physical performance in strength and power, team, and aerobic sports disciplines. Carrying specific PPAR alleles can provide a partial benefit to achieving elite sports status, but does not preclude achieving elite status if they are absent.

Meta-analyses of the association between the PPARGC1A Gly482Ser polymorphism and athletic performance

Peroxisome proliferator-activated receptor γ coactivator 1α (PGC1α) encoded by the PPARGC1A gene is a vital regulator of glucose and fatty acid oxidation, mitochondrial biogenesis, and skeletal muscle fibre conversion. Several studies have investigated the association between PPARGC1A Gly482Ser polymorphism and athletic performance in humans. However, the results were contradictory. In the present study, two meta-analyses were performed to assess the association between the Gly482Ser polymorphism and endurance or power athletic performance to resolve this inconsistency. Ten articles were identified, including a total of 3,708 athletes and 6,228 controls. Higher frequencies of the Gly/Gly genotype (OR, 1.26; 95% CI, 1.11-1.42) and the Gly allele (OR, 1.29; 95% CI, 1.09-1.52) were observed in Caucasian endurance athletes. Furthermore, higher incidences of the Gly/Gly genotype (OR, 1.30; 95% CI, 1.16-1.46) and the Gly allele (OR, 1.22; 95% CI, 1.12-1.33) were observed in power athletes compared to controls. This finding demonstrates that the Gly/Gly genotype and the Gly allele of the PPARGC1A Gly482Ser polymorphism may facilitate athletic performance regardless of the type of sport, as well as providing solid evidence to support the possible influence of genetic factors on human athletic performance.

Genetic Markers Associated with Power Athlete Status

Athletic performance is a multifactorial phenotype influenced by environmental factors as well as multiple genetic variants. Different genetic elements have a great influence over components of athletic performance such as endurance, strength, power, flexibility, neuromuscular coordination, psychological traits and other features important in sport. The current literature review revealed that to date more than 69 genetic markers have been associated with power athlete status. For the purpose of the present review we have assigned all genetic markers described with reference to power athletes status to seven main groups: 1) markers associated with skeletal muscle structure and function, 2) markers involved in the inflammatory and repair reactions in skeletal muscle during and after exercise, 3) markers involved in blood pressure control, 4) markers involved in modulation of oxygen uptake, 5) markers that are regulators of energy metabolism and cellular homeostasis, 6) markers encoding factors that control gene expression by rearrangement of chromatin fibers and mRNA stability, and 7) markers modulating cellular signaling pathways. All data presented in the current review provide evidence to support the notion that human physical performance may be influenced by genetic profiles, especially in power sports. The current studies still represent only the first steps towards a better understanding of the genetic factors that influence power-related traits, so further analyses are necessary before implementation of research findings into practice.

The Polymorphisms of the Peroxisome-Proliferator Activated Receptors' Alfa Gene Modify the Aerobic Training Induced Changes of Cholesterol and Glucose

Background: PPARα is a transcriptional factor that controls the expression of genes involved in fatty acid metabolism, including fatty acid transport, uptake by the cells, intracellular binding, and activation, as well as catabolism (particularly mitochondrial fatty acid oxidation) or storage. PPARA gene polymorphisms may be crucial for maintaining lipid homeostasis and in this way, being responsible for developing specific training-induced physiological reactions. Therefore, we have decided to check if post-training changes of body mass measurements as well as chosen biochemical parameters are modulation by the PPARA genotypes. Methods: We have examined the genotype and alleles’ frequencies (described in PPARA rs1800206 and rs4253778 polymorphic sites) in 168 female participants engaged in a 12-week training program. Body composition and biochemical parameters were measured before and after the completion of a whole training program. Results: Statistical analyses revealed that PPARA intron 7 rs4253778 CC genotype modulate training response by increasing low-density lipoproteins (LDL) and glucose concentration, while PPARA Leu162Val rs1800206 CG genotype polymorphism interacts in a decrease in high-density lipoproteins (HDL) concentration. Conclusions: Carriers of PPARA intron 7 rs4253778 CC genotype and Leu162Val rs1800206 CG genotype might have potential negative training-induced cholesterol and glucose changes after aerobic exercise.

Association of PPARGC1A Gly428Ser (rs8192678) polymorphism with potential for athletic ability and sports performance: A meta-analysis

Background

Genetics plays a role in determining potential for athletic ability (AA) and sports performance (SP). In this study, AA involves comparing sedentary controls with competitive athletes in power and endurance activities as well as a mix between the two (SP). However, variable results from genetic association studies warrant a meta-analysis to obtain more precise estimates of the association between PPARGC1A Gly482Ser polymorphism and AA/SP.

Methods

Multi-database literature search yielded 14 articles (16 studies) for inclusion. Pooled odds ratios (ORs) and 95% confidence intervals (CI) were used to estimate associations. Summary effects were modified based on statistical power. Subgroup analysis was based on SP (power, endurance and mixed) and race (Caucasians and Asians). Heterogeneity was assessed with the I² metric and its sources examined with outlier analysis which dichotomized our findings into pre- (PRO) and post-outlier (PSO).

Results

Gly allele effects significantly favoring AA/SP (OR > 1.0, P < 0.05) form the core of our findings in: (i) homogeneous overall effect at the post-modified, PSO level (OR 1.13, 95% CI 1.03–1.25, P = 0.01, I² = 0%); (ii) initially homogeneous power SP (ORs 1.22–1.25, 95% CI 1.05–1.44, P = 0.003–0.008, I² = 0%) which precluded outlier treatment; (iii) PRO Caucasian outcomes (ORs 1.29–1.32, 95% CI 1.12–1.54, P = 0.0005) over that of Asians with a pooled null effect (OR 0.99, 95% CI 0.72–1.99, P = 0.53–0.92) and (iv) homogeneous all > 80% (ORs 1.19–1.38, 95% CI 1.05–1.66, P = 0.0007–0.007, I² = 0%) on account of high statistical power (both study-specific and combined). In contrast, none of the Ser allele effects significantly favored AA/SP and no Ser-Gly genotype outcome favored AA/SP. The core significant outcomes were robust and showed no evidence of publication bias.

Conclusion

Meta-analytical applications in this study generated evidence that show association between the Gly allele and AA/SP. These were observed in the overall, Caucasians and statistically powered comparisons which exhibited consistent significance, stability, robustness, precision and lack of bias. Our central findings rest on association of the Gly allele with endurance and power, differentially favoring the latter over the former.

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 < .001), ACE ID (p < .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 < .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 COMT genes 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.

Association between the PPARa and PPARGCA gene variations and physical performance in non-trained male adolescents

The purpose of the research was to examine if some genetic variations are associated with some endurance, power and speed performances (multi-stage 20-m shuttle run, standing broad jump, 20 m sprint test and Abalakov jump) in a group of 586 non-trained male adolescents (mean ± SD age: 13.20 ± 0.25 years). Polymorphisms in PPARa and PPARGC1A implicated in physical performance traits were analyzed. DNA was extracted and the samples were genotyped for PPARa and PPARGC1A polymorphisms by a PCR based method followed by gel electrophoresis. The discrepancies in the study phenotypes among variations of the PPARa and PPARGC1A polymorphisms were analyzed by one-way analysis of covariance (ANCOVA), after age, weight and height adjustment. To examine whether the genotype and allele frequencies between adolescents with high and low performances were different, we divided them into two groups: ≥ 90th and < 90th of the percentile. The genotype and allele frequencies between adolescents with high and low performances were compared with the Chi square test. Our analysis demonstrated the effects of the PPARa and PPARGC1A polymorphisms only on [Formula: see text] (p = 0.010 and p = 0.010 respectively). Also, we observed significant differences in PPARa and PPARGC1A genotypes (p = 0.034 and p = 0.024) or allele frequencies (p = 0.031 and p = 0.001) between groups for the multi-stage 20-m shuttle run test. Findings of this research suggest that both the PPARa and PPARGC1A polymorphisms are associated with estimating endurance-related phenotype and endurance capacity in male non-athletes adolescents.

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 specialised 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.

Analysis of sports-relevant polymorphisms in a large Brazilian cohort of top-level athletes

In recent years, there have been an increasing number of genetic variants associated with athletic phenotypes. Here, we selected a set of sports-relevant polymorphisms that have been previously suggested as genetic markers for human physical performance, and we examined their association with athletic status in a large cohort of Brazilians. We evaluated a sample of 1,622 individuals, in which 966 were nonathletes, and 656 were athletes: 328 endurance athletes and 328 power athletes. Only the AGT M268T minor allele was nominally associated with the endurance status. Conversely, we found that seven polymorphisms are more frequent in power athletes (MCT1 D490E, AGT M268T, PPARG P12A, PGC1A G482S, VEGFR2 Q472H, NOS3 C/T, and ACTN3 R577X). For all of these polymorphisms, power athletes were more likely than nonathletes or endurance athletes to carry the major allele or the homozygous genotype for the major allele. In particular, MCT1 D490E, AGT M268T, NOS3 C/T, and ACTN3 R577X showed stronger associations. Our findings support a role for these variants in the achievement of power athletic status in Brazilians: MCT1 D490E (T allele), AGT M268T (G allele), PPARG (C allele), PGC1A G482S (C allele), VEGFR2 Q472H (T allele), NOS3 C/T (T allele), and ACTN3 R577X (R allele).

Gly482Ser PGC-1α Gene Polymorphism and Exercise-Related Oxidative Stress in Amyotrophic Lateral Sclerosis Patients

The role of exercise in Amyotrophic lateral sclerosis (ALS) pathogenesis is controversial and unclear. Exercise induces a pleiotropic adaptive response in skeletal muscle, largely through the peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), a transcriptional coactivator that regulates mitochondrial biogenesis and antioxidant defense mechanisms. It has been suggested that a Gly482Ser substitution in PGC-1α has functional relevance in human disorders and in athletic performance. To test this hypothesis, we examined the genotype distribution of PGC-1α Gly482Ser (1444 G > A) in ALS patients to evaluate whether or not the minor serine-encoding allele 482Ser is involved in oxidative stress responses during physical exercise. We genotyped 197 sporadic ALS patients and 197 healthy controls in order to detect differences in allelic frequencies and genotype distribution between the two groups. A total of 74 ALS patients and 65 controls were then comparatively assessed for plasmatic levels of the oxidative stress biomarkers, advanced oxidation protein products, ferric reducing ability and thiol groups. In addition a subgroup of 35 ALS patients were also assessed for total SOD and catalase plasmatic activity. Finally in 28 ALS patients we evaluated the plasmatic curve of the oxidative stress biomarkers and lactate during an incremental exercise test. No significant differences were observed in the genotype distribution and allelic frequency in ALS patients compared to the controls. We found significant increased advanced oxidation protein products (p < 0.001) and significant decreased ferric reducing ability (p < 0.001) and thiol groups (p < 0.001) in ALS patients compared to controls. When comparing different genotypes of PGC-1α, no relation between Gly482Ser polymorphism and oxidative stress biomarker levels was detected in resting conditions. On the other hand, when considering exercise performance, lactate levels were significantly higher (between p < 0.01 and p < 0.001) and greater protein oxidative products were found in AA (Ser482Ser) compared to GG (Gly482Gly) and GA (Gly482Ser) ALS patients. Our findings highlight the importance and confirm the involvement of oxidative stress in ALS pathogenesis. Although not associated with 1444 G > A SNP, ALS patients with Gly482Ser allelic variant show increased exercise-related oxidative stress. This thus highlights the possible role of this antioxidant defense transcriptional coactivator in ALS.

Evaluation of a 7-Gene Genetic Profile for Athletic Endurance Phenotype in Ironman Championship Triathletes

Polygenic profiling has been proposed for elite endurance performance, using an additive model determining the proportion of optimal alleles in endurance athletes. To investigate this model’s utility for elite triathletes, we genotyped seven polymorphisms previously associated with an endurance polygenic profile (ACE Ins/Del, ACTN3 Arg577Ter, AMPD1 Gln12Ter, CKMM 1170bp/985+185bp, HFE His63Asp, GDF8 Lys153Arg and PPARGC1A Gly482Ser) in a cohort of 196 elite athletes who participated in the 2008 Kona Ironman championship triathlon. Mean performance time (PT) was not significantly different in individual marker analysis. Age, sex, and continent of origin had a significant influence on PT and were adjusted for. Only the AMPD1 endurance-optimal Gln allele was found to be significantly associated with an improvement in PT (model p = 5.79 x 10⁻¹⁷, AMPD1 genotype p = 0.01). Individual genotypes were combined into a total genotype score (TGS); TGS distribution ranged from 28.6 to 92.9, concordant with prior studies in endurance athletes (mean±SD: 60.75±12.95). TGS distribution was shifted toward higher TGS in the top 10% of athletes, though the mean TGS was not significantly different (p = 0.164) and not significantly associated with PT even when adjusted for age, sex, and origin. Receiver operating characteristic curve analysis determined that TGS alone could not significantly predict athlete finishing time with discriminating sensitivity and specificity for three outcomes (less than median PT, less than mean PT, or in the top 10%), though models with the age, sex, continent of origin, and either TGS or AMPD1 genotype could. These results suggest three things: that more sophisticated genetic models may be necessary to accurately predict athlete finishing time in endurance events; that non-genetic factors such as training are hugely influential and should be included in genetic analyses to prevent confounding; and that large collaborations may be necessary to obtain sufficient sample sizes for powerful and complex analyses of endurance performance.

Sports genetics: the PPARA gene and athletes' high ability in endurance sports. A systematic review and meta-analysis

A meta-analysis was performed with the aim of re-evaluating the role of the peroxisome proliferator activated receptor alpha (PPARA) gene intron 7 G/C polymorphism (rs4253778) in athletes’ high ability in endurance sports. Design: A meta-analysis of case control studies assessing the association between the G/C polymorphisms of the PPARA gene and endurance sports was conducted. The Cochrane Review Manager software was used to compare the genotype and allele frequencies between endurance athletes and controls to determine whether a genetic variant is more common in athletes than in the general population. Five studies, encompassing 760 endurance athletes and 1792 controls, fulfilled our inclusion criteria. The pooled odds ratio (and confidence intervals, CIs) for the G allele compared to the C allele was 1.65 (95% CI 1.39-1.96). The pooled OR for the GG genotype compared to the GC genotype was 1.79 (95% CI 1.44-2.22), and for the GG genotype compared to the CC genotype 2.37 (95% CI 1.40-3.99). There was no evidence of heterogeneity (I² =0%) or of publication bias. Athletes with high ability in endurance sports had a higher frequency of the GG genotype and G allele.

The heritable path of human physical performance: from single polymorphisms to the "next generation"

Human physical performance is a complex multifactorial trait. Historically, environmental factors (e.g., diet, training) alone have been unable to explain the basis of all prominent phenotypes for physical performance. Therefore, there has been an interest in the study of the contribution of genetic factors to the development of these phenotypes. Support for a genetic component is found with studies that shown that monozygotic twins were more similar than were dizygotic twins for many physiological traits. The evolution of molecular techniques and the ability to scan the entire human genome enabled association of several genetic polymorphisms with performance. However, some biases related to the selection of cohorts and inadequate definition of the study variables have complicated the already difficult task of studying such a large and polymorphic genome, often resulting in inconsistent results about the influence of candidate genes. This review aims to provide a critical overview of heritable genetic aspects. Novel molecular technologies, such as next-generation sequencing, are discussed and how they can contribute to improving understanding of the molecular basis for athletic performance. It is important to ensure that the large amount of data that can be generated using these tools will be used effectively by ensuring well-designed studies.

Current Progress in Sports Genomics

Understanding the genetic architecture of athletic performance is an important step in the development of methods for talent identification in sport. Research concerned with molecular predictors has highlighted a number of potentially important DNA polymorphisms contributing to predisposition to success in certain types of sport. This review summarizes the evidence and mechanistic insights on the associations between DNA polymorphisms and athletic performance. A literature search (period: 1997-2014) revealed that at least 120 genetic markers are linked to elite athlete status (77 endurance-related genetic markers and 43 power/strength-related genetic markers). Notably, 11 (9%) of these genetic markers (endurance markers: ACE I, ACTN3 577X, PPARA rs4253778 G, PPARGC1A Gly482; power/strength markers: ACE D, ACTN3 Arg577, AMPD1 Gln12, HIF1A 582Ser, MTHFR rs1801131 C, NOS3 rs2070744 T, PPARG 12Ala) have shown positive associations with athlete status in three or more studies, and six markers (CREM rs1531550 A, DMD rs939787 T, GALNT13 rs10196189 G, NFIA-AS1 rs1572312 C, RBFOX1 rs7191721 G, TSHR rs7144481 C) were identified after performing genome-wide association studies (GWAS) of African-American, Jamaican, Japanese, and Russian athletes. On the other hand, the significance of 29 (24%) markers was not replicated in at least one study. Future research including multicenter GWAS, whole-genome sequencing, epigenetic, transcriptomic, proteomic, and metabolomic profiling and performing meta-analyses in large cohorts of athletes is needed before these findings can be extended to practice in sport.

PGC-related gene variants and elite endurance athletic status in a Chinese cohort: a functional study

This study aims to examine the association between proliferator-activated receptor γ (PGC)-gene family-related single nucleotide polymorphisms (SNPs) and elite endurance runners' status in a Chinese cohort, and to gain insights into the functionality of a subset of SNPs. Genotype distributions of 133 SNPs in PPARGC1A, PPARGC1B, PPRC1, TFAM, TFB1M, TFB2M, NRF1, GABPA, GABPB1, ERRα, and SIRT1 genes were compared between 235 elite Chinese (Han) endurance runners (127 women) and 504 healthy non-athletic controls (237 women). Luciferase gene reporter activity was determined in 20 SNPs. After adjusting for multiple comparisons (in which threshold P-value was set at 0.00041), no significant differences were found in allele/genotype frequencies between athletes and controls (when both sexes were analyzed either together or separately). The lowest P-value was found in PPARGC1A rs4697425 (P = 0.001 for the comparison of allele frequencies between elite female endurance runners and their gender-matched controls). However, no association (all P > 0.05) was observed for this SNP in a replication cohort from Poland (194 endurance athletes and 190 controls). Using functional genomics tool, the following SNPs were found to have functional significance: PPARGC1A rs6821591, rs12650562, rs12374310, rs4697425, rs13113110, and rs4452416; PPARGC1B rs251466 and rs17110586; and PPRC1 rs17114388 (all P < 0.001). This study found no significant association between PGC-related SNPs and elite endurance athlete status in the Chinese population, despite some SNPs showing potential functional significance and the strong biological rationale to hypothesize that this gene pathway is a candidate to influence endurance exercise capacity.

Elite athletes' genetic predisposition for altered risk of complex metabolic traits

BACKGROUND

Genetic variants may predispose humans to elevated risk of common metabolic morbidities such as obesity and Type 2 Diabetes (T2D). Some of these variants have also been shown to influence elite athletic performance and the response to exercise training. We compared the genotype distribution of five genetic Single Nucleotide Polymorphisms (SNPs) known to be associated with obesity and obesity co-morbidities (IGF2BP2 rs4402960, LPL rs320, LPL rs328, KCJN rs5219, and MTHFR rs1801133) between athletes (all male, n = 461; endurance athletes n = 254, sprint/power athletes n = 207), and controls (all male, n = 544) in Polish and Russian samples. We also examined the association between these SNPs and the athletes' competition level ('elite' and 'national' level). Genotypes were analysed by Single-Base Extension and Real-Time PCR. Multinomial logistic regression analyses were conducted to assess the association between genotypes and athletic status/competition level.

RESULTS

IGF2BP2 rs4402960 and LPL rs320 were significantly associated with athletic status; sprint/power athletes were twice more likely to have the IGF2BP2 rs4402960 risk (T) allele compared to endurance athletes (OR = 2.11, 95% CI = 1.03-4.30, P <0.041), and non-athletic controls were significantly less likely to have the T allele compared to sprint/power athletes (OR = 0.62, 95% CI =0.43-0.89, P <0.0009). The control group was significantly more likely to have the LPL rs320 risk (G) allele compared to endurance athletes (OR = 1.26, 95% CI = 1.05-1.52, P <0.013). Hence, endurance athletes were the "protected" group being significantly (p < 0.05) less likely to have the risk allele compared to sprint/power athletes (IGF2BP2 rs4402960) and significantly (p < 0.05) less likely to have the risk allele compared to controls (LPL rs320). The other 3 SNPs did not show significant differences between the study groups.

CONCLUSIONS

Male endurance athletes are less likely to have the metabolic risk alleles of IGF2BP2 rs4402960 and LPL rs320, compared to sprint/power athletes and controls, respectively. These results suggest that some SNPs across the human genome have a dual effect and may predispose endurance athletes to reduced risk of developing metabolic morbidities, whereas sprint/power athletes might be predisposed to elevated risk.

Association between the PPARGC1A polymorphism and aerobic capacity in Japanese middle-aged men

OBJECTIVE

A lower frequency for the peroxisome proliferator-activated receptor γ coactivator 1α (PPARGC1A) Ser482 allele has been reported in elite-level endurance athletes among Caucasians, although this gene polymorphism has not been found to be associated with aerobic capacity in German, Dutch or Chinese populations. The purpose of the current study was to examine the associations between the Gly482Ser polymorphism and aerobic fitness in 112 Japanese middle-aged men.

METHODS

The PPARGC1A Gly482Ser polymorphism was identified according to a TaqMan(®) SNP genotyping assay. Habitual physical activity was objectively measured using an accelerometer. The lactate threshold (LT), an index of aerobic fitness, was measured based on a submaximal graded exercise test performed on an electric cycle ergometer. The association between the LT and the Gly482Ser polymorphism was assessed according to a multiple regression analysis and analysis of covariance, with adjustment for potential confounders (age, body mass index, cigarette smoking, physical activity level and regular exercise).

RESULTS

A significant association was observed between the PPARGC1A Gly482Ser polymorphism and LT, as carriers of the Ser482 had higher LT values than the Gly482 carriers.

CONCLUSION

The current results suggest that the PPARGC1A Ser482 allele is associated with a higher aerobic capacity in Japanese middle-aged men.

PPARα gene variants as predicted performance-enhancing polymorphisms in professional Italian soccer players

Background

The PPARα gene encodes the peroxisome proliferator-activator receptor alpha, a central regulator of expression of other genes involved in fatty acid metabolism. The purpose of this study was to determine the prevalence of G allele of the PPARα intron 7 G/C polymorphism (rs4253778) in professional Italian soccer players.

Methods

Sixty professional soccer players and 30 sedentary volunteers were enrolled in the study. Samples of venous blood were obtained at rest, in the morning, by conventional clinical procedures; blood serum was collected and total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides were measured. An aliquot of anticoagulant-treated blood was used to prepare genomic DNA from whole blood. The G/C polymorphic site in PPARα intron 7 was scanned by using the PCR-RFLP (polymerase chain reaction restriction fragment length polymorphism) protocol with TaqI enzyme.

Results

We found variations in genotype distribution of PPARα polymorphism between professional soccer players and sedentary volunteers. Particularly, G alleles and the GG genotype were significantly more frequent in soccer players compared with healthy controls (64% versus 48%). No significant correlations were found between lipid profile and genotype background.

Conclusion

Previous results demonstrated an association of intron 7 G allele as well as the GG genotype in endurance athletes. Our result suggests that this is the case also in professional soccer players.

PPARA intron polymorphism associated with power performance in 30-s anaerobic Wingate Test

To date, polymorphisms in several genes have been associated with a strength/power performance including alpha 3 actinin, ciliary neurotrophic factor, vitamin D receptor, or angiotensin I converting enzyme, underlining the importance of genetic component of the multifactorial strength/power-related phenotypes. The single nucleotide variation in peroxisome proliferator-activated receptor alpha gene (PPARA) intron 7 G/C (rs4253778; g.46630634G>C) has been repeatedly found to play a significant role in response to different types of physical activity. We investigated the effect of PPARA intron 7 G/C polymorphism specifically on anaerobic power output in a group of 77 elite male Czech ice hockey players (18-36 y). We determined the relative peak power per body weight (Pmax.kg(-1)) and relative peak power per fat free mass (W.kg(-1)FFM) during the 30-second Wingate Test (WT30) on bicycle ergometer (Monark 894E Peak bike, MONARK, Sweden). All WT30s were performed during the hockey season. Overall genotype frequencies were 50.6% GG homozygotes, 40.3% CG heterozygotes, and 9.1% CC homozygotes. We found statistically significant differences in Pmax.kg(-1) and marginally significant differences in Pmax.kg(-1)FFM values in WT30 between carriers and non-carriers for C allele (14.6 ± 0.2 vs. 13.9 ± 0.3 W.kg(-1) and 15.8 ± 0.2 vs. 15.2 ± 0.3 W.kg(-1)FFM, P = 0.036 and 0.12, respectively). Furthermore, Pmax.kg(-1)FFM strongly positively correlated with the body weight only in individuals with GG genotypes (R = 0.55; p<0.001). Our results indicate that PPARA 7C carriers exhibited higher speed strength measures in WT30. We hypothesize that C allele carriers within the cohort of trained individuals may possess a metabolic advantage towards anaerobic metabolism.

PPAR-α and PPARGC1A gene variants have strong effects on aerobic performance of Turkish elite endurance athletes

The aim of this study was to investigate the effect of PPAR-α intron 7G>C and PPARGC1A gene Gly482Ser polymorphisms on aerobic performance of elite level endurance athletes. This study was carried out on 170 individuals (60 elite level endurance athletes and 110 sedentary controls). Aerobic performance of athletes and sedentary control groups were defined by maximal oxygen uptake capacity. DNA was isolated from peripheral blood using GeneJet Genomic DNA Purification kit. Genotyping of the PPAR-α intron 7G>C and PPARGC1A Gly482Ser polymorphisms was performed using PCR-RFLP methods, and statistical evaluations were carried out using SPSS 15.0. Mean age of athletes were 21.38 ± 2.83 (18-29) and control mean age were 25.92 ± 4.88 (18-35). Mean maximal oxygen consumption of athletes were 42.14 ± 7.6 ml/(kg min) and controls were 34.33 ± 5.43 ml/(kg min). We found statistically significant differences between the athlete and control groups with respect to both PPAR-α and PPARGC1A genotype distributions (p = 0.006, <0.001, respectively) and allele frequencies (<0.001, <0.001, respectively). Additionally, when we examined PPAR-α and PPARGC1A genotype distributions according to the aerobic performance test parameters, we found a statistically significant association between velocity, time and maximal oxygen consumption and PPAR-α and PPARGC1A genotypes (p < 0.001). To our knowledge, this is the first study in Turkey examined PPAR-α intron 7G>C and PPARGC1A Gly482Ser gene polymorphisms in elite level endurance athletes. Our results suggest that PPAR-α and PPARGC1A genes have strong effect on aerobic performance of elit level athletes.

The FTO A/T polymorphism and elite athletic performance: a study involving three groups of European athletes

Objective

The FTO A/T polymorphism (rs9939609) is a strong candidate to influence obesity-related traits. Elite athletes from many different sporting disciplines are characterized by low body fat. Therefore, the aim of this study was to assess whether athletic status is associated with the FTO A/T polymorphism.

Subjects and Methods

A large cohort of European Caucasians from Poland, Russia and Spain were tested to examine the association between FTO A/T polymorphism (rs9939609) and athletic status. A total of 551 athletes were divided by type of sport (endurance athletes, n = 266 vs. sprint/power athletes, n = 285) as well as by level of competition (elite-level vs. national-level). The control group consisted of 1,416 ethnically-matched, non-athletic participants, all Europeans. Multinomial logistic regression analyses were conducted to assess the association between FTO A/T genotypes and athletic status/competition level.

Results

There were no significantly greater/lesser odds of harbouring any type of genotype when comparing across athletic status (endurance athletes, sprint/power athletes or control participants). These effects were observed after controlling for sex and nationality. Furthermore, no significantly greater/lesser odds ratios were observed for any of the genotypes in respect to the level of competition (elite-level vs. national-level).

Conclusion

The FTO A/T polymorphism is not associated with elite athletic status in the largest group of elite athletes studied to date. Large collaborations and data sharing between researchers, as presented here, are strongly recommended to enhance the research in the field of exercise genomics.

Mitochondrial DNA variation is associated with elite athletic status in the Polish population

There is mounting evidence that genetic factors located in mitochondrial and nuclear genomes influence sport performance. Certain mitochondrial haplogroups and polymorphisms were associated with the status of elite athlete, especially in endurance performance. The aim of our study was to assess whether selected mitochondrial DNA (mtDNA) and nuclear DNA variants are associated with elite athlete performance in a group of 395 elite Polish athletes (213 endurance athletes and 182 power athletes) and 413 sedentary controls. Our major finding was that the mtDNA haplogroup H and HV cluster influence endurance performance at the Olympic/World Class level of performance (P = 0.018 and P = 0.0185, respectively). We showed that two polymorphisms located in the mtDNA control region were associated with achieving the elite performance level either in the total athlete's group as compared with controls (m.16362C, 3.8% vs 9.2%, respectively, P = 0.0025, odds ratio = 0.39, 95% confidence interval: 0.21-0.72), or in the endurance athletes as compared with controls (m.16080G, 2.35% vs 0%, respectively, P = 0.004). Our results indicate that mtDNA variability affects the endurance capacity rather than the power one. We also propose that mtDNA haplogroups and subhaplogroups, as well as individual mtDNA polymorphisms favoring endurance performance, could be population-specific, reflecting complex cross-talk between nuclear and mitochondrial genomes.

Variation in the ACE, PPARGC1A and PPARA genes in Lithuanian football players

The aim of this study was to determine the impact of ACE (I/D), PPARGC1A (G/A) and PPARA (G/C) polymorphisms on footballers performance among 199 Lithuanian professional footballers and 167 sedentary, healthy men (controls). Genotyping was performed using polymerase chain reaction and restriction fragment length polymorphism methods on DNA from leucocytes. Results revealed that the angiotensin-1-coverting enzyme gene (ACE) genotype distribution was significantly different between total football players group (II 23.6%, ID 46.7% and DD 29.6%) and the controls (II 24.6%, ID 29.9% and DD 45.5%; P=0.002). Although investigating PPARGC1A (G/A) and PPARA (G/C) polymorphisms no significant results were obtained in the total football players group, however, significant differences were determined between forwards and controls [PPARGC1A: GG 54.6%, GA 29.5%, AA 15.9% vs. GG 49.7%, GA 44.3% and AA 6.0% (P = 0.044); PPARA: GG 52.3%, GC 40.9%, CC 6.8% vs. GG 72.4%, GC 24.6% and CC 3.0% (P = 0.034)]. In the whole cohort, the odds ratio of the genotype [ACE ID + PPARA GG] being a footballer was 1.69 (95% CI 1.04-2.74), and of [ACE ID + PPARGC1A GG] 1.93 (95% CI 1.10-3.37) and of [ACE II + PPARA GC] 2.83 (95% CI 1.02-7.91) compared to controls. It was revealed that ACE ID genotype together with PPARA GG and PPARGC1A GG as well as ACE II genotype with PPARA GC is probably the 'preferable genotype' for footballers. Summing up, the present study suggests that the ACE, PPARGC1A and PPARA polymorphisms genotypes are associated, separately and in combination, with Lithuanian footballers' performance.

The PPARGC1A gene Gly482Ser in Polish and Russian athletes

Peroxysome proliferator-activated receptor gamma coactivator-1-alpha (PGC-1α; encoded by the gene PPARGC1A in humans) is a crucial component in training-induced muscle adaptation because it is a co-activator of transcriptional factors that control gene expression in coordinated response to exercise. It has been suggested that a Gly482Ser substitution in PPARGC1A has functional relevance in the context of human disorders and athletic performance. To test this hypothesis, we examined the genotype distribution of PPARGC1A Gly482Ser in a group of Polish athletes and confirmed the results obtained in a replication study of Russian athletes. We found that the 482Ser allele was under-represented in the cohort of Polish and Russian athletes examined compared with unfit controls (P < 0.0001). A statistically significant low frequency of the 482Ser allele was observed among the endurance,strength-endurance, and sprint-strength groups of Polish athletes (P = 0.019, P = 0.022, and P < 0.0001, respectively). The replication study revealed that the 482Ser allele was also less prevalent in Russian endurance and strength-endurance athletes (P = 0.029 and P < 0.0001, respectively). Our results suggest that the PPARGC1A Gly482Ser polymorphism is associated with elite endurance athletic status. These findings support the hypothesis that the PPARGC1A 482Ser allele may impair aerobic capacity: thus, the Gly482 allele may be considered a beneficial factor for endurance performance.

Is PPARα intron 7 G/C polymorphism associated with muscle strength characteristics in nonathletic young men?

Peroxisome proliferator-activated receptor alpha (PPARα), a ligand-dependent transcription factor, regulates fatty acid metabolism in heart and skeletal muscle. The intron 7 G/C polymorphism (rs4253778) has been associated with athletic performance. The rare C-allele was predominant in power athletes, whereas the G-allele was more frequent in endurance athletes. In the present study, we investigated the association between this polymorphism and strength characteristics in nonathletic, healthy young adults (n = 500; age 24.2 ± 4.4 years). Knee torque was measured during concentric knee flexion and extension movements at 60°/s, 120°/s, and 240°/s during 3, 25, and 5 repetitions, respectively. Also, resistance to muscle fatigue (i.e. work last 20% repetitions/work first 20% repetitions *100) was calculated. Differences in knee strength phenotypes between GG homozygous individuals and C-allele carriers were analyzed. The polymorphism did not influence the ability to produce isometric or dynamic knee flexor or extensor peak torque during static or dynamic conditions in this population (0.23 < P < 0.95). Similar results were found for the endurance ratio, a measure for resistance to muscle fatigue. In conclusion, the PPARα intron 7 G/C polymorphism does not seem to influence strength characteristics in a nonathletic population.

The champions' mitochondria: is it genetically determined? A review on mitochondrial DNA and elite athletic performance

Aerobic ATP generation by the mitochondrial respiratory oxidative phosphorylation system (OXPHOS) is a vital metabolic process for endurance exercise. Notably, mitochondrial DNA (mtDNA) codifies 13 of the 83 polypeptides implied in the respiratory chain. As such, there is a strong rationale for identifying an association between mtDNA variants and “aerobic” (endurance) exercise phenotypes. The aim of this review is to summarize current knowledge on the association between mtDNA, nuclear genes involved in mitochondriogenesis, and elite endurance athletic status. Several studies in nonathletic people have demonstrated an association between certain mtDNA lineages and aerobic performance, characterized by maximal oxygen uptake (V̇o2max). Whether mtDNA haplogroups are also associated with the status of being an elite endurance athlete is more controversial, with differences between studies arising from the different ethnic backgrounds of the athletic cohorts (Caucasian of mixed geographic origin, Asiatic, or East African).

Physiological variables and mitochondrial-related genotypes of an athlete who excels in both short and long-distance running

We report the athletic, physiological and mitochondrial-related genomic data of an Israeli endurance runner. He is holding the Israeli record in 10,000, 5000, 1500 and 800 m run, along with being one of the best Israeli 400 m runners. We tested the ACTN3 R577X, and six polymorphisms in the PPARGC1A-NRF-TFAM pathway genes. The case athlete was heterozygous for the ACTN3 R577X variation and had five out of six 'endurance-oriented' genotypes, scoring significantly high in endurance 'optimal' genotype profile. In conclusion, we suggest that the case athlete is favoured by polygenic profile that is more suitable for mitochondrial biogenesis, regardless of his good phenotypic accomplishments in short-term running events.

Mitochondrial biogenesis related endurance genotype score and sports performance in athletes

We determined the probability of individuals having the 'optimal' mitochondrial biogenesis related endurance polygenic profile, and compared the endurance polygenic profile of Israeli (Caucasian) endurance athletes (n = 74), power athletes (n = 81), and non-athletes (n = 240). We computed a mitochondrial biogenesis related 'endurance genotype score' (EGS, scoring from 0 to 100) from the accumulated combination of six polymorphisms in the PPARGC1A-NRF-TFAM pathway. Some of the variant alleles of the polymorphisms studied were so infrequent, that the probability of possessing an 'optimal' EGS (= 100) was 0% in the entire study population. However, the EGS was significantly higher (P<0.001) in endurance athletes (38.9 ± 17.1) compared with controls (30.6 ± 12.4) or power athletes (29.0 ± 11.2). In summary, although the probability of an individual possessing a theoretically 'optimal' genetic background for endurance sports is very low, in general endurance athletes have a polygenic profile that is more suitable for mitochondrial biogenesis.

Is there an interaction between PPARD T294C and PPARGC1A Gly482Ser polymorphisms and human endurance performance?

Functional Gly482Ser (rs8192678) and T294C (rs2016520) polymorphisms in the peroxisome proliferator-activated receptor gamma coactivator-1 (PPARGC1A) and peroxisome proliferator-activated receptor delta (PPARD) genes, respectively, have been associated with mRNA and/or protein activity. The aim of this study was to determine their frequency distribution among 155 Israeli athletes (endurance athletes and sprinters) and 240 healthy control subjects. There were no differences between the endurance athletes, the sprinters and the control group across the PPARD T294C genotypes (P = 0.62). Similarly, no statistical differences were found between the subgroups of elite-level endurance athletes (those who had represented Israel in a world track and field championship or in the Olympic Games) and national-level endurance athletes (P = 0.3), or between elite-level and national-level sprinters (P = 0.9). However, a combined influence of these two polymorphisms on endurance performance was found. The PPARD CC + PPARGC1A Gly/Gly genotypes were more frequently found in the elite endurance athletes than in national-level endurance athletes (P < 0.000). In the cohort of endurance athletes, the odds ratio of the 'optimal genotype' for endurance athletes (PPARD CC + PPARGC1A Gly/Gly + PPARGC1A Gly/Ser) being an elite-level athlete was 8.32 (95% confidence interval 2.2-31.4). In conclusion, the present study suggests that PPARD T294C is not associated with endurance performance. However, a higher frequency of the PPARGC1A Gly/Gly + PPARD CC genotype is associated with elite-level endurance athletes.

NRF2 intron 3 A/G polymorphism is associated with endurance athletes' status

The aim of this study was to determine the frequency distribution of nuclear respiratory factor 2 (NRF2) intron 3 A/G polymorphism (rs7181866) among 155 Israeli athletes (endurance athletes and sprinters) and 240 healthy controls. Results showed that there was a significantly higher proportion of the AG genotype, rather than the AA genotype, in the group of endurance athletes compared with the sprinters (P = 0.014) and controls (P = 0.0008). However, the sprinters' genotype and allele frequencies were similar to those of the control group (P = 0.62 for genotype distribution percentage). These results were even more pronounced when we compared between the subgroups of 20 elite endurance athletes (those who had represented Israel in a world track-and-field championship or in the Olympic Games) and 54 national-level endurance athletes. In the group of elite endurance athletes the G allele was more frequent than in the national-level endurance athletes (P = 0.047). We conclude that 1) in Israeli athletes the NRF2 AG genotype is more frequent in elite endurance athletes than in sprinters, and 2) within the endurance group the NRF2 AG genotype and the G allele are more frequent in elite athletes, suggesting a positive association between the AG genotype, and possibly the G allele, and the likelihood of being an elite endurance athlete.