Associação dos genótipos da ACTN3 aos indicadores de desempenho em atletas juvenis da natação brasileira especialistas em curtas distâncias

Abstract

Foi objetivo da pesquisa identificar a frequência genotípica da ACTN3 e associa-la ao índice técnico (IT) e ao status de elite em 98 atletas juvenis de natação (16,80 ± 0,63 anos) especialistas em curtas distâncias (≤ 200m). Um grupo controle (GC) com 101 escolares não-atletas (16,52 ± 0,94 anos) foi incluído nas comparações. Os grupos foram analisados sem divisão por sexo. Os atletas foram divididos pelas experiências competitivas em elite (internacionais, n = 15) e sub-elite (nacionais, n = 83). Não verificou-se diferenças significativas (X2) na frequência genotípica entre atletas sub-elite e GC. Os atletas de elite apresentaram supremacia do genótipo RX (60,0%), baixa frequência do genótipo RR (13,3%), supremacia do alelo X (54,2%) e da adição RX+XX (86,7%). O ajuste das frequências genotípicas pelo quartil superior (QS) do IT revelou que os atletas com genótipos RR+RX apresentaram maior pontuação média (820,6 ± 40,0) quando comparados aos atletas XX (806,7 ± 34,8). Atletas de elite do grupo QS (RR+RX) apresentaram valores médios do IT ainda mais expressivos (853,9 ± 31,3). Os genótipos da ACTN3 demonstraram boa associação aos fenótipos da força/potência apenas entre os atletas identificados nos mais altos níveis de desempenho. 

Association between ACTN3 (R577X), ACE (I/D), BDKRB2 (-9/+9), and AGT (M268T) polymorphisms and performance phenotypes in Brazilian swimmers

“…The majority of studies involving candidate polymorphisms related to swimming performance have given more attention to either ACTN3 or ACE polymorphisms [ 3 , 5 , 14 – 19 ]. In addition, other polymorphisms have also been investigated, such as the NOS3 genes (G894T and − 786T/C) [ 20 ], insulin-like growth factor ( IGF ) [ 21 ], myostatin ( MSTN ) [ 22 ], as well as interleukin-6 (IL6), MCT1, peroxisome proliferator-activated receptor alpha ( PPARA ), PPARG coactivator 1 alpha ( PPARGC1A ) and vascular endothelial growth factor receptor 2 ( VEGFR2 ) [ 23 , 24 ].…”

“…The ACTN3 polymorphism has been extensively studied and associated with elite athletic performance [ 35 , 36 ], including among swimming athletes [ 3 , 5 , 16 , 18 , 37 ]. The results of the present study showed that, regarding the ACTN3 gene, individuals with the XX genotype are 1.79 times more likely to belong to the athlete group when compared to the control group.…”

“…In the field of genetics applied to elite swimming, studies point out interactions between genotypic profiles of some candidate polymorphisms and strength/power phenotypes, associated with short-distance events (≤ 200 m) performed in Olympic-size swimming pools [ 3 ]. In short-distance swimming events, the alpha-actinin-3 ( ACTN3 ) polymorphism is associated with power/strength phenotypes, with emphasis on the higher frequency of the R allele and the RR and RX genotypes [ 5 ]. The angiotensin-converting enzyme ( ACE ) I allele and II + ID genotypes are commonly associated with endurance phenotypes, especially among top-elite long-distance specialist athletes [ 3 ].…”

Interaction Between ACTN3 (R577X), ACE (I/D), and BDKRB2 (−9/+9) Polymorphisms and Endurance Phenotypes in Brazilian Long-Distance Swimmers

“…In these studies, the strength/power phenotype is associated with short-distance events, whereas the endurance phenotype is associated with long-distance events (3,5,6,9,10,17,23,26). However, there are few studies with young swimmers (18), especially experts in long-distance events. Likewise, no investigation has been geared to determine the distribution of these polymorphisms athletes expert in open water swimming (25).…”