Paweł Cięszczyk

The ACTN3 R577X Polymorphism across Three Groups of Elite Male European Athletes

The ACTN3 R577X polymorphism (rs1815739) is a strong candidate to influence elite athletic performance. Yet, controversy exists in the literature owing to between-studies differences in the ethnic background and sample size of the cohorts, the latter being usually low, which makes comparisons difficult. In this case:control genetic study we determined the association between elite athletic status and the ACTN3 R577X polymorphism within three cohorts of European Caucasian men, i.e. Spanish, Polish and Russian [633 cases (278 elite endurance and 355 power athletes), and 808 non-athletic controls]. The odds ratio (OR) of a power athlete harbouring the XX versus the RR genotype compared with sedentary controls was 0.54 [95% confidence interval (CI): 0.34–0.48; P = 0.006]. We also observed that the OR of an endurance athlete having the XX versus the RR genotype compared with power athletes was 1.88 (95%CI: 1.07–3.31; P = 0.028). In endurance athletes, the OR of a “world-class” competitor having the XX genotype versus the RR+RX genotype was 3.74 (95%CI: 1.08–12.94; P = 0.038) compared with those of a lower (“national”) competition level. No association (P>0.1) was noted between the ACTN3 R577X polymorphism and competition level (world-class versus national-level) in power athletes. Our data provide comprehensive support for the influence of the ACTN3 R577X polymorphism on elite athletic performance.

The PPARGC1Agene Gly482Ser in Polish and Russian athletes

Abstract 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.

Gene variants within the COL1A1 gene are associated with reduced anterior cruciate ligament injury in professional soccer players

OBJECTIVES To examine the association of the COL1A1 -1997G/T and +1245G/T polymorphisms, individually and as haplotypes, with anterior cruciate ligament ruptures in professional soccer players. DESIGN Subjects were 91 male professional soccer players with surgically diagnosed primary anterior cruciate ligament ruptures. The control group consisted of 143 apparently healthy male professional soccer players, who were without any self-reported history of ligament or tendon injury. Both subjects and healthy controls are from the same soccer teams, of the same ethnicity (Polish, East-Europeans for ≥3 generations), a similar age category, and had a comparable level of exposure to anterior cruciate ligament injury. METHODS Genomic DNA was extracted from the oral epithelial cells using GenElute Mammalian Genomic DNA Miniprep Kit (Sigma, Germany). All samples were genotyped using a Rotor-Gene real-time polymerase chain reaction. RESULTS Genotype distributions for both polymorphisms met the Hardy-Weinberg expectations in both subjects and controls (p>0.05). Higher frequency of the COL1A1 G-T (-1997G/T and +1245G/T polymorphisms) haplotype was significantly associated with reduced risk for anterior cruciate ligament rupture (Hap.score -1.98, p=0.048). The TT genotype was under-represented in the anterior cruciate ligament rupture group. However, this result was not statistically significant (p=0.084 Fishers exact test, recessive mode: TT vs GT+GG). CONCLUSIONS Higher frequency of the COL1A1 G-T haplotype is associated with reduced risk of anterior cruciate ligament injury in a group of professional soccer players. Consequently, carrying two copies the COL1A1 G-T haplotype may be protective against anterior cruciate ligament injury.

The Angiotensin Converting Enzyme Gene I/D Polymorphism in Polish Rowers

Angiotensin converting enzyme gene (ACE) is the most frequent investigated gene in the context of genetic conditioning of sports-predispositions. Product of this gene is a key-element in the renin-angiotensin system responsible for the regulation of blood pressure. In this study DNA polymorphism in the ACE gene was studied in Polish rowers in order to examine the hypothesis that ACE genotype is associated with athletes performance. Fifty-five male Polish rowers including Olympic and World champions were recruited for this study. Control samples were prepared from 115 unrelated volunteers. PCR amplification of the insertion (I) or deletion (D) fragment of ACE gene was performed. Genotype distribution and allele frequencies were determined by genotype and gene counting. Significance was assessed by chi2 analysis. ACE genotype distributions amongst subjects and controls were in Hardy-Weinberg equilibrium. Compared with controls, the frequency of I allele differ significantly from that found in rowers group: 56.3% vs. 44.3%, (P=0.038) and ACE genotype frequency amongst the whole athletes group (30.9% II, 50.9% ID, 18.2% DD) was also different from expected values (control group 19.1% II, 50.4% ID, 30.4% DD; P=0.039). This data confirm a positive association of the I allele of ACE gene with endurance performance.

Variation in the PPARα gene in Polish rowers

The PPARα gene code for transcriptional factor that is a central regulator of expression of genes involved in fatty acid metabolism and is believed to be a one of the genes of health-related fitness phenotype. The aim of this study was to examine the hypothesis that G allele of PPARα intron 7 G/C polymorphic site (rs4253778) is positively associated with endurance athlete status. PPARα genotypes were analyzed for 55 Polish rowers: 30 elite rowers representing the highest national competitive standard and 25 non-elite rowers representing regional standard. Control samples were prepared from 115 unrelated volunteers. The G/C polymorphic site in PPARα intron 7 was scanned by using PCR-RFLP protocol with TaqI enzyme. The allele frequency and genotype distribution was determined by gene and genotype counting. Significance was assessed by χ² analysis. The obtained results revealed that frequency of the PPARα GG genotype (87% vs. 63%; p=0.04) and G allele (93% vs. 79%; p=0.009) were significantly higher in the elite group of the Polish rowers compared to sedentary controls. These data confirm that GG genotype is more prevalent in the group of endurance athletes therefore G allele may be considered as one of the endurance-related allele.

Association of the ACTN3 R577X Polymorphism in Polish Power-Orientated Athletes

Association of the ACTN3 R577X Polymorphism in Polish Power-Orientated Athletes Alpha-actinins are an ancient family of actin-binding proteins that play structural and regulatory roles in cytoskeletal organization. In skeletal muscle, α-actinin-3 protein is an important structural component of the Z disc, where it anchors actin thin filaments, helping to maintain the myofibrillar array. A common nonsense polymorphism in codon 577 of the ACTN3 gene (R577X) results in α-actinin-3 deficiency in XX homozygotes. Based on knowledge about the role of ACTN3 R557X polymorphism in skeletal muscle function, we postulated that the genetic polymorphism of ACTN3 could also improve sprint and power ability. We compared genotypic and allelic frequencies of the ACTN3 R557X polymorphism in two groups of men of the same Caucasian descent: 158 power-orientated athletes and 254 volunteers not involved in competitive sport. The genotype distribution in the group of power-oriented athletes showed significant differences (P=0.008) compared to controls. However, among the investigated subgroups of athletes, only the difference of ACTN3 R577X genotype between sprinters and controls reached statistical significance (P=0.041). The frequencies of the ACTN3 577X allele (30.69% vs. 40.35%; P=0.005) were significantly different in all athletes compared to controls. Our results support the hypothesis that the ACTN3 577XX allele may have some beneficial effect on sprintpower performance, because the ACTN3 XX genotype is significantly reduced in Polish power-oriented athletes compared to controls. This finding seems to be in agreement with previously reported case-control studies. However, ACTN3 polymorphism as a genetic marker for sport talent identification should be interpreted with great caution.

ACTN3 R577X polymorphism and team-sport performance : a study involving three European cohorts

OBJECTIVES To determine the association between the α-actinin-3 (ACTN3) R577X polymorphism and elite team-sport athletic status in three cohorts of European team-sport athletes. DESIGN We compared the genotype and allele frequencies of the ACTN3 R577X (rs1815739) polymorphisms between team-sport athletes (n=205), endurance athletes (n=305), sprint/power athletes (n=378), and non-athletic controls (n=568) from Poland, Russia and Spain; all participants were unrelated European men. METHODS Genomic DNA was extracted from either buccal epithelium or peripheral blood using a standard protocol. Genotyping was performed using several methods, and the results were replicated following recent recommendations for genotype-phenotype association studies. RESULTS Genotype distributions of all control and athletic groups met Hardy-Weinberg equilibrium (all p>0.05). Team-sport athletes were less likely to have the 577RR genotype compared to the 577XX genotype than sprint/power athletes [odds ratio: 0.58, 95% confidence interval: 0.34-0.39, p=0.045]. However, the ACTN3 R577X polymorphism was not associated with team-sports athletic status, compared to endurance athletes and non-athletic controls. Furthermore, no association was observed for any of the genotypes with respect to the level of competition (elite vs. national level). CONCLUSIONS The ACTN3 R577X polymorphism was not associated with team-sport athletic status, compared to endurance athletes and non-athletic controls, and the observation that the 577RR genotype is overrepresented in power/sprint athletes compared with team-sport athletes needs to be confirmed in future studies.

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.

The +1245g/t polymorphisms in the collagen type I alpha 1 (col1a1) gene in polish skiers with anterior cruciate ligament injury.

Objectives The aim of this study was to examine the association of +1245G/T polymorphisms in the COL1A1 gene with ACL ruptures in Polish male recreational skiers in a case-control study. Methods A total of 138 male recreational skiers with surgically diagnosed primary ACL ruptures, all of whom qualified for ligament reconstruction, were recruited for this study. The control group comprised 183 apparently healthy male skiers with a comparable level of exposure to ACL injury, none of whom had any self-reported history of ligament or tendon injury. DNA samples extracted from the oral epithelial cells were genotyped for the +1245G/T polymorphisms using real-time PCR method. Results Genotype distributions among cases and controls conformed to Hardy-Weinberg equilibrium (p = 0.2469 and p = 0.33, respectively). There was a significant difference in the genotype distribution between skiers and controls (p = 0.045, Fishers exact test). There was no statistical difference in allele distribution: OR 1.43 (0.91-2.25), p = 0.101 (two-sided Fishers exact test). Conclusions The risk of ACL ruptures was around 1.43 times lower in carriers of a minor allele G as compared to carriers of the allele T.

Chapter Four - Genomics of Elite Sporting Performance: What little We Know and Necessary Advances

Numerous reports of genetic associations with performance- and injury-related phenotypes have been published over the past three decades; these studies have employed primarily the candidate gene approach to identify genes that associate with elite performance or with variation in performance-and/or injury-related traits. Although generally with small effect sizes and heavily prone to type I statistic error, the number of candidate genetic variants that can potentially explain elite athletic status, injury predisposition, or indeed response to training will be much higher than that examined by numerous biotechnology companies. Priority should therefore be given to applying whole genome technology to sufficiently large study cohorts of world-class athletes with adequately measured phenotypes where it is possible to increase statistical power. Some of the elite athlete cohorts described in the literature might suffice, and collectively, these cohorts could be used for replication purposes. Genome-wide association studies are ongoing in some of these cohorts (i.e., Genathlete, Russian, Spanish, Japanese, United States, and Jamaican cohorts), and preliminary findings include the identification of one single nucleotide polymorphism (SNP; among more than a million SNPs analyzed) that associates with sprint performance in Japanese, American (i.e., African American), and Jamaican cohorts with a combined effect size of ~2.6 (P-value <5×10(-7)) and good concordance with endurance performance between select cohorts. Further replications of these signals in independent cohorts will be required, and any replicated SNPs will be taken forward for fine-mapping/targeted resequencing and functional studies to uncover the underlying biological mechanisms. Only after this lengthy and costly process will the true potential of genetic testing in sport be determined.