This patent application claims priority from Italian patent application no. 102019000006196 filed on Apr. 19, 2019, the entire disclosure of which is incorporated herein by reference.
The present invention relates to a method to predict the predisposition to an exercise performance trait in a human individual comprising assaying for the presence of polymorphisms in each of the following genes: ACTN3, COL5A1, MCT1, VEGF, HFE.
Training for elite athletes is a complex task that needs to be adapted not only to specific sports but also to the individual predisposition of each single athlete. Among others, soccer is considered a total and very demanding sport that requires the concomitant training of different body systems, such as muscular, cardio-circulatory, respiratory and nervous system often supported by specific nutrients supplementation. This multi-parametric training fulfils different physical and nutritional requirements that, in turn, might improve muscle size and strength, endurance, resistance to fatigue, and coordination.
Although the physical and metabolic features of each athlete are considered to be the main parameters to design specific training programs, it is currently accepted the impact of genetic traits on the success of a given training. Advances in science and technology could in principle change the way in which soccer players are subjected to training programs designed in a personalized perspective. The inclusion of genetics in the design of training programs (PEP, Performance Enhancing Polymorphisms) was triggered by the identification of a large number of genetic variants, linked to the athletic performances (Ostrander et al., 2009).
The correlation between specific gene polymorphisms and the response to physical and nutritional cues can then be explored to evaluate athlete's profiles. This would allow the development of tailored programs that maximize the athletic performances and reduce the occurrence of indirect injuries.
It is an object of the present invention to provide a method to predict the predisposition in a human individual to an exercise performance trait, in particular predisposition to muscular and/or ligament injuries.
This object is achieved by means of the method as defined in claim 1.
Other objects of the present invention are to provide the use of ACTN3, COL5A1, VEGF, MCT1, and HFE gene sequences as defined in claim 9 and the kit as defined in claim 10.
The method for predicting the predisposition to an exercise performance trait in a human individual according to the present invention comprises the following steps.
First, a genetic sample obtained from the human individual is assayed for the presence of at least one genetic variation in each of the following genes:
ACTN3 Gene ID: 89; SNP Accession number: rs1815739
COL5A1 Gene ID: 1289; SNP Accession number: rs12722
VEGF Gene ID: 7422; SNP Accession number: rs2010963
MCT1 Gene ID: 6566; SNP Accession number: rs1049434
HFE Gene ID: 3077; SNP Accession number: rs1799945 to obtain a polymorphism profile.
Then, a regression function associated to the polymorphism profile is determined.
Finally, the individual's predisposition to the exercise performance trait is classified on the basis of the value of said regression function.
The exercise performance trait is preferably endurance predisposition, muscular power, or predisposition to muscular and/or ligament injuries. More preferably, the exercise performance trait is predisposition to muscular and/or ligament injuries.
The human individual is preferably an athlete, more preferably a soccer player.
The 5 genes ACTN3, COL5A1, VEGF, MCT1, and HFE were identified by mining literature for genes previously correlated to athletic performances, such as endurance capacity, lactic acid clearance, iron intake and clearance, muscle fatigue.
ACTN3 encodes the a-actinin 3, a protein responsible for fast muscle fibers functioning (Lee et al., 2016). The ACTN3 R577X polymorphism is suspected, since several years (Yang et al., 2003), to be associated to particular athletic performances in power-oriented elite athletes of different ethnicities. This polymorphism is, at genomic level, a C to T transition in position 18705 and, at protein level an Arginine to X mutation in position 577 (R577X). The polymorphism can be present in homozygosis (DNA: TT or protein: XX), in heterozygosis (DNA: CT or Protein: RX) or absent (DNA: CC or protein: RR). The CC (RR at protein level) and CT (RX at protein level) genotypes were initially found increased in frequency in elite strength athletes, in agreement with the fact that the TT (XX) mutation was previously associated with impaired muscle performance. (Roth et al., 2008). The enrichment in CC and CT genotypes, however, was not confirmed by different large-scale studies (Massidda et al., 2015b; Rankinen et al., 2016) casting doubts on the original interpretation and on the differences between elite athletes and the general population. However, the exact genotype indeed plays a role in differentiating among athletes of the same discipline, since in a study on 200 Brazilian football players, the presence of a CC genotype was associated with players fastest in short distances and with higher jump potential, while the TT genotype was associated with higher aerobic capacity (Pimenta et al., 2013). Very recently, the TT genotype has been robustly associated with a higher incidence of muscle injuries (Massidda et al., 2017).
Thus, preferably, the genetic variation of ACTN3 is a C to T polymorphism in position 18705 of the gene.
COL5A1 encodes the al chain of type V collagen, mainly found in ligaments and tendons and associated with severity of musculoskeletal injuries (Massidda et al., 2015a). A C to T single nucleotide polymorphism (rs12722) in the 3′ untranslated region of COL5A1 gene improves mRNA stability and, in turn, protein production resulting in an increased amount of type V collagen (Abrahams et al., 2014; Bertuzzi et al., 2014). This increase in Collagen V is capable of altering the mechanical properties of tendons and may result in an increased predisposition to tendons and ligaments injuries.
Thus, preferably, the genetic variation of COL5A1 is a C to T polymorphism in position 205765 of the gene.
MCT1 encodes a lactate transporter (Merezhinskaya et al., 2000) and is responsible of the uptake of lactate by Type I oxidative fibers. Its activity has the double beneficial effect of: i) reducing the circulating levels of lactate and ii) increasing the levels of lactate in the muscle fibers that can use it as fuel. Interestingly MCT1 expression levels are increased upon high-intensity trainings, enforcing its role in enhancing the athletic performances through lactate reabsorption. A performance enhancing polymorphism (rs1049434) in the MCT1 gene has been identified in position 47005 of the gene, corresponding to an A to T transversion which results in a Glutamic acid to Aspartic acid substitution in position 490 of the protein (Glu490Asp). Compared to carriers of the A allele, the presence of the minor allele (T) is causative of a 2-fold reduction in lactate transport by MCT1 (Merezhinskaya et al., 2000) and has been correlated with higher levels of blood lactate during high-intensity training (Cupeiro et al., 2010). These findings highlight the impact that MCT1 A>T polymorphism may have on endurance performances and on athlete's response to specific training. It has been demonstrated however that the frequency of the T allele of MCT1 was high in elite sprinters, suggesting that reduced lactate uptake by type I oxidative fibers is not adverse to anaerobic activities (Kikuchi et al., 2017; Sawczuk et al., 2015). By contrast, the T-allele may be deleterious for the aerobic and endurance activities (such as football playing).
Thus, preferably, the genetic variation of MCT1 is an A to T polymorphism in position 47005 of the gene.
VEGF encodes the Vascular Endothelial Growth Factor, associated with an improvement of aerobic performances (Prior et al., 2006). Variations of the DNA sequence in the promoter of VEGF have been correlated with different levels of VEGF expression. It has been reported that a C to G polymorphism in the VEGF promoter at position 5398 of the gene is causative, when in homozygosis (GG), of a reduced expression of VEGF in hypoxic conditions and this causes, in turn, a reduced maximal oxygen consumption. However, it has also been demonstrated that whenever the polymorphism occurs in heterozygosis (CG) the VEGF expression under hypoxia are null and VO2max (training-induced increased oxygen consumption) is not affected.
Thus, preferably, the genetic variation of VEGF is a C to G polymorphism in position 5398 of the gene.
HFE (High Fe; hereditary haemochromatosis gene) encodes a transmembrane protein involved in blood and tissue iron homeostasis (Luszczyk et al., 2017). Although HFE is not an iron transporter, it interacts and regulates the activity of proteins, such as the transferrin receptor (being a negative regulator of it), that directly controls iron uptake from blood circulation, and the ferroportin, a transmembrane protein that clears iron from the cell excreting it into the blood. HFE is thus able to control the homeostasis of iron (Barton et al., 2015). Loss of function of HFE results in a genetic disease known as haemochromatosis, characterized by excessive accumulation of iron into the organism. However, high iron content, below the pathological threshold, may be beneficial for athletic performances. The HFE C187G polymorphism results, at protein level, in the substitution of a Histidine with an Aspartic acid in position 63 (H63D; rs1799945) with the subsequent reduction of HFE function. HFE H63D has a reduced ability to bind to transferrin receptor, thus resulting in an increased transport of iron into blood and cells. Although a clear association of HFE H63D polymorphism with elite athletic performances has not been established, it is worth to note that in several studies a higher frequency of HFE H63D has been found in endurance athletes such as cyclists (Chicharro et al., 2004; Deugnier et al., 2002). Iron is extremely important for oxygen transport and delivery to the muscles; thus it is reasonable that any impairment of iron uptake would result in an increase of circulating iron and an increase in oxygen availability, conditions that are both important for the execution of aerobic performances.
Thus, preferably, the genetic variation of HFE is a C to G polymorphism in position 8671 of the gene.
In particular the combination of the C>T polymorphism in position 18705 of ACTN3 gene, of the C>T polymorphism in position 205765 of COL5A1 gene; of the A>T polymorphism in position 47005 of MCT1 gene; of the C>G polymorphism in position 5398 of VEGF gene, of the C>G polymorphism in position 8671 of HFE gene is associated, through a regression function, with muscular and/or ligament injuries.
In the method according to the present invention, the regression function is preferably a logistic regression function of the form:
Log(P(Response=n injuries)/P(Response=not n injuries))=−intercept+genotype1*A+genotype2*B+ . . . genotypeN+X
In particular, the appropriate coefficients (capital letters in the previous equation) and the appropriate genotypes are reported vs. the number of muscular injuries in the following table:
The method preferably comprises assaying the genetic sample obtained from the human individual for the presence of at least one genetic variation in at least one other gene to obtain a polymorphism profile. Examples of such genes are ACEI, AMPD1, CKMM1, GDF8, PPARGC1A, mtND5, IGF1, IGFBP3, DRD2/ANKK1, SVIL, SLC22A3, NRP2, TTN, H19, ID3, MIPEP, CPVL, DEPDC6, BTAF1, DIS3L.
According to the present invention, the ACTN3, COL5A1, VEGF, MCT1, and HFE gene sequences, wherein the ACTN3 polymorphism in position 18705 is C>T, the COL5A1 polymorphism in 205765 is C>T, the MCT1 polymorphism in position 47005 is A>T, the VEGF polymorphism in position 5398 is C>G, and the HFE polymorphism in position 8671 is C>G or sequences reverse complementary thereto, may be used in determining the predisposition to muscular and/or ligament injuries in a human individual.
The present invention also relates to a kit for predicting the predisposition to an exercise performance trait in a human individual comprising a reagent for assaying a genetic sample obtained from the human individual for the presence of at least one genetic variation in each of the following genes: ACTN3, COL5A1, MCT1, VEGF, HFE.
The present inventors carried out a study with the medical staff of the SSC Napoli, in which 32 elite football players, subjected to the standard sport medical evaluation and practices, were also screened for genetic polymorphism in 5 key genes (ACTN3, COL5A1, MCT1, VEGF, HFE) that, at different extent, have been correlated to athletic performances and to injuries predisposition.
The screening for the genetic polymorphisms in the 5 genes was carried out by standard techniques such as PCR amplification of genomic DNA followed by sequencing or real-time PCR.
The analysis of the polymorphisms in the above said 5 genes represents the central point of a multidisciplinary method that can be adopted by elite football teams to obtain an improvement of athletic performances and a concomitant reduction of injuries by tailoring training and nutritional programs to the genetic background of each athlete. The genetic fingerprinting of single athletes led the inventors to the identification of two performance enhancing polymorphisms (ACTN3 18705C>T and VEGF-634C>G) significantly enriched in the SSC Naples football players. Moreover, a genetic model was devised based on the polymorphisms in the entire gene set analyzed, which was used to reduce the athlete predisposition to injuries by dictating a personalized nutrition and training program.
The usefulness of such approach is concordant with data showing that the SSC Napoli football team has been recently found as the healthiest and least injured team in Europe, while covering the highest distance/match with the highest number of high intensity actions/match.
More in particular,
The SSC Naples football team presents a high frequency of TT homozygotes, which is statistically different from controls and athletes in all the above-mentioned studies. In line with results reported for football players (Pimenta et al., 2013) this might indicate that, on average, SSC Naples athletes have higher aerobic capacity. Furthermore, very recently, the TT genotype has been robustly associated with a higher incidence of muscle injuries (Massidda et al., 2017). Considering these last findings, the SSC Naples medical staff designed personalized training programs for the players with the ACTN3 TT genotype, aiming to reduce the risk of muscular injuries for these players. The overall athletic performances of SSC Naples, recognized by the Lega Calcio Serie A, agreed with a possible effect of the optimized training program. (
COL5A1 rs12722 polymorphism (C to T) distribution in the cohort analyzed in this study highlights a prevalence of heterozygous (CT) genotype, that accounts for the majority of athletes (44%) compared to the homozygous genotypes CC (22%) and TT (34%) (
The SSC Naples 32 football players were screened for the rs2010963 polymorphism (−634C>G). The three possible genotypes CC, CG, GG are represented as follows. The heterozygous (CG) is the single most diffuse genotype (46%), as compared to the homozygous genotypes CC (22%) and GG (32%) (
The occurrence of MCT1 A1470T polymorphism was analysed in the 32 SSC Naples football players; the three possible genotypes AA, AT, TT turned to be distributed with a prevalence of heterozygous (AT) genotype, that accounts for most athletes (46%) as compared to the homozygous genotypes AA (23%) and GG (31%) (
The HFE H63D polymorphism, exclusively in heterozygosis with the wild type allele (CG genotype) has been found in 22% of the SSC Naples football players (
From the single-gene analysis discussed so far, it turned out that the SSC Naples team is predicted to be negatively influenced at the genetic level by the measured frequency of ACTN3 haplotypes, which predisposes the players to muscular injuries, and by specific MCT1 haplotypes positively affecting the iron transport, which turned out to be less abundant in comparison to other teams playing in Italy. However, the team is also well disposed by its VEGF superior genetic makeup, predicted to confer high aerobic capacities and in agreement with the reported team's highest distance/match covered and highest number of high intensity actions/match performed.
A different question to be answered was whether the combined effect of the 5 genes included in the analysis could explain the individual predisposition of the single football players to muscular and/or ligament injuries. The target variable considered for the analysis (i.e. the quantity to be predicted) was the overall amount of injuries occurring to a given player during the season 2014-2018, and as predictor its genetic makeup at the 5 considered genes.
The overall number of muscular injuries occurred to each player is reported in the following table.
Complete genetic information was available only for 27 players. Assuming as regression variable the number of muscular incidents, a multinomial fitting of a logistic model based on the players genotype was performed. After the regression, an almost complete separation of observations was detected, with the following very good determination coefficients: R2(McFadden)=0.953, R2(Cox and Snell)=0.876, R2(Nagelkerke)=0,986. The goodness of the fit is demonstrated by a Chi-square=56.446; with the available degrees of freedom, the probability of finding a value of Chi-square equal or superior in case the null hypothesis is true (i.e. there is no correlation between the genetic makeup and the number of injuries for any given player) is p=0,016, thus below the usual significance alpha threshold of p=0.05. In agreement with such a good and significant fitting, the players' reclassification table obtained by applying the identified model to the 27 considered players is the following:
As evident from the table, the prediction of the number of injuries based on the obtained model is wrong in only a single case (a player which was injured only once is back-predicted to have incurred in no injuries).
This is the most accurate athletic injuries predictive model known so far, relying on the thoughtful selections of 5 genes already involved in athletic performances, which were however never tested simultaneously for their predictive power. With the help of this model, the SSC Naples medical staff or the staff of other football teams can now in principle focus their efforts on players most at risk, tuning their training programs and giving them useful insights, so to optimize the performances of the athletes.
As can be seen from the Examples, among the 5 genes selected for this study, ACTN3, COL5A1 and VEGF influence the athletic performances and the indirect injury predisposition, independently of any nutritional supply. The effect of these performance enhancing polymorphisms may be enhanced or counteracted only by developing a personalized training. For other two genes, MCT1 and HFE, in which performance enhancing polymorphisms have been identified, a nutritional intervention along with the development of specific training programs may be undertaken to counteract their negative or enhance their positive influences.
Moreover, it has been shown that the combination of the five genes has a strong predictive power. The obtained regression indicates that the identified 5 genes-performance association could, at least in part, explain why an athlete is more susceptible to injuries than another one, so that, it can be used to identify athletes which need special cares during training sessions and special attention when taking the field and could support the development of tailored injury prevention programs and/or targeted therapeutic interventions.
Number | Date | Country | Kind |
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102019000006196 | Apr 2019 | IT | national |
Filing Document | Filing Date | Country | Kind |
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PCT/IB2020/053667 | 4/17/2020 | WO | 00 |