Physiological, anthropometric and psychological traits are partially inheritable; that’s why there’s a growing interest to find new techniques which can help predict sports talent through the use of genetics. One of the most used advances in this field is the identification of variations in the DNA sequence, known as Single-Nucleotide Polymorphisms (SNPs), as some variations are associated with factors that can affect sports performance. A recent review has described up to 155 genetic markers that could be related to an “elite athletic profile” (2).

One of the most popular variations in this field is the so-called “speed gene”, the ACTN3. A simple substitution of a Cytosine base for Thymine in this gene creates a deficient expression of a protein related to fast fibres. People who have both alleles modified (genotype XX) have a lower percentage of fast fibres, which can have an impact on sports performance. For this reason, having the RR alleles (unmodified) is related to a sprinter or a power profile. On the other hand, the XX genotype seems to be associated with the opposite phenotype. However, it is important to mention that, although some studies have found that sprint athletes have a lower incidence of genotype XX (1,7), others have not found differences between the control population and sprinting athletes (Jamaicans and Americans) (6). Even a study carried out by Lucía and collaborators (3) found that a Spanish long jumper who attended the 2012 Olympics had the XX (the “slow”) genotype. This jumper under this genetic analysis, would not seem to have an “elite” profile, although he was only 5 cm away from achieving the gold medal in London.

Based on these results, a recent review carried out by the doctors Alejandro Lucía and Juan del Coso (4), both state that “identifying talent using a single gene is not feasible. It seems clear that the profile of an elite athlete is a polygenic trait, so, if genetic tests are to be used to identify possible sports talents, it is necessary to discover a greater number of polymorphisms and then combine them in complex models of Genotype Score (TGS).” Based on this and the commercial genetic techniques currently used, the authors mention that “with the available data and the information provided by these tests to identify sports talent, especially among children, is unfounded.”

However, even when there will be more accurate data and tools available, such as genome-wide association studies (GWAS) or TGS threshold setting for high-performance athletes, the frequency of high-level athletes will be significantly different from that provided by genetics. In fact, there are many other factors that contribute to the birth of an elite athlete, such as external factors (economic status, social support) or environmental factors that can modulate the gene expression during critical periods of development (epigenetics). For this reason, the authors conclude that “it seems unlikely that it will ever be possible to use genetic information to unequivocally identify a future elite athlete. At best, genetic information can represent a potentially useful complement to existing talent by improving the selection process and allowing the training process to become more personalized. This can enhance athletes by allowing them to get closer to their maximum potential”.

The Barça Innovation Hub team

REFERENCES

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2. Ahmetov, II, Egorova, ES, Gabdrakhmanova, LJ, and Fedotovskaya, ON. Genes and Athletic Performance: An Update. In: Medicine and Sport Science (Vol. 61).2016. pp. 41–54Available from: https://www.karger.com/DOI/10.1159/000445240
3. Lucia, A, Oliván, J, Gómez-Gallego, F, Santiago, C, Montil, M, and Foster, C. Citius and longius (faster and longer) with no α-actinin-3 in skeletal muscles? Br J Sports Med 41: 616 LP – 617, 2007.Available from: http://bjsm.bmj.com/content/41/9/616.abstract
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7. Yang, N, MacArthur, DG, Gulbin, JP, Hahn, AG, Beggs, AH, Easteal, S, et al. <em>ACTN3</em> Genotype Is Associated with Human Elite Athletic Performance. Am J Hum Genet 73: 627–631, 2003.Available from: https://doi.org/10.1086/377590