Is there an optimum endurance polygenic profile?

Abstract

We analysed seven genetic polymorphisms that are candidates to explain individual variations in human endurance phenotypic traits, at least in Caucasian people (ACE Ins/Del, ACTN3 Arg577Ter, AMPD1 Gln12Ter, CKMM 1170 bp/985 + 185 bp, HFE His63Asp, GDF-8 Lys153Arg and PPARGC1A Gly482Ser) in 46 world-class endurance athletes and 123 controls (all Spanish Caucasians). Using the model developed by Williams & Folland we determined (1) the 'total genotype score' (TGS, from the accumulated combination of the seven polymorphisms, with a maximum value of '100' for the theoretically optimal polygenic score) in the non-athlete (control) group, in the athlete group and in the total Spanish population, and (2) the probability for the occurrence of Spanish individuals with the 'perfect' polygenic endurance profile (i.e. TGS = 100). The probability of a Spanish individual possessing a theoretically optimal polygenic profile for up to the seven candidate genetic polymorphisms we studied was very small, i.e. ∼0.07% (or 1 in 1351 Spanish individuals). The mean TGS was higher in athletes (70.22 ± 15.58) than in controls (62.43 ± 11.45) and also higher than predicted for the total Spanish population (60.80 ± 12.1), suggesting an overall more 'favourable' polygenic profile in the athlete group. However, only three of the best Spanish endurance athletes (who are also amongst the best in the world) had the best possible score for up to six genes and none of them had the optimal profile. Other polymorphisms yet undiscovered as well as several factors independent of genetic endowment may explain why some individuals reach the upper end of the endurance performance continuum.

GNB3C825T Polymorphism and Elite Athletic Status: A Replication Study with Two Ethnic Groups

“…Thus, rather that the individual eff ect of a given polymorphism, it is likely the combined infl uence of several genetic variants, each with a signifi cant contribution, as well as the complex interaction of genetic variants (with or without an individual contribution) that explain individual variations in endurance / power performance [15,16,20] . Further research models in the fi eld of sports genetics should thus account for the polygenic nature of sports related phenotypes.…”

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

“…These individuals have undergone extreme physiological adaptations (e.g. in muscle oxidative capacity, as a result of increased mitochondrial content) that are likely to be the consequence of years of training as well as of the interaction between exercise training and a favorable polygenic profile (Ruiz et al 2009). In the present study, our case athlete represents even more "exceptional" model by holding the all times Israeli national records in 10,000m and 800 m running events, and by being one of the best Israeli 400m runners.…”

ACTN 3 e desempenho esportivo: um gene candidato ao sucesso em provas de curta e longa duração.<br>DOI:10.5007/1980-0037.2011v13n6p477

“…Porém, essa ausência da proteína funcional não resulta em quadro patológico ou qualquer alteração fenotípica evidente, sugerindo que a α-actinina-2 pode suprir a falta da isoforma -3. Apesar disso, existem evidências de que os diferentes genótipos desse polimorfismo podem influenciar o desempenho de atletas de diferentes modalidades 8 . Do ponto de vista evolutivo, o alelo 577X do gene ACTN3 foi um dos dois únicos alelos polimórficos que apresentaram uma recente seleção positiva, ou seja, tiveram suas frequências aumentadas em determinada população 37 .…”

“…Alguns estudos demonstraram que certos polimorfismos de DNA podem possuir relação com o rendimento esportivo, tanto em modalidades de curta duração e com elevada demanda da força muscular 5 , quanto em provas de longa duração, dependentes primordialmente do metabolismo aeróbio 6,7 . Dessa forma, a maioria dos estudos mais recentes que analisam fatores genéticos e sua influência no esporte tem verificado a expressão de proteínas estruturais do músculo-esquelético e de enzimas relacionadas ao metabolismo energético 6,8,9 . Entre os diversos genes polimórficos que têm sido associados ao desempenho esportivo, destaca--se o ACTN3, o qual codifica a α-actinina-3, uma proteína pertencente ao componente estrutural do músculo esquelético.…”