ACTN3 genotype and swimming performance in Taiwan

Area of Science:

• Sports Science
• Human Genetics
• Exercise Physiology

Background:

• The alpha-actinin-3 (ACTN3) gene, specifically the 577R allele, is associated with sprint athletic performance.
• Understanding ACTN3 genotype distribution is crucial for talent identification and performance optimization in athletes.

Purpose of the Study:

• To investigate the distribution of ACTN3 R577X genotypes and alleles in Taiwanese sprint swimmers and the general population.
• To examine the relationship between ACTN3 genotypes and swimming performance changes after training in pre-adolescent and adult males.

Main Methods:

• Genotyping of ACTN3 R577X (rs 1815739) in 603 general Taiwanese individuals and 168 elite sprint swimmers.
• Analysis of swimming performance (25-m time) before and after a 12-week training program in 50 pre-adolescent and 38 adult males.

Main Results:

• Significantly higher frequencies of the ACTN3 577R allele were observed in female international sprint swimmers (67.6%) compared to national swimmers (50.0%) and the general population (53.7%).
• Pre-adolescent males showed significant 25-m performance improvements across all ACTN3 genotypes post-training, with the RR genotype performing best, though not statistically significant.
• Male pre-adolescents with ACTN3 RX or XX genotypes exhibited greater performance improvements than RR genotype individuals.

Conclusions:

• The ACTN3 577R allele is more prevalent in elite female sprint swimmers, suggesting a genetic predisposition for power-oriented athletic endeavors.
• ACTN3 genotype influences training adaptations in young male swimmers, with non-RR genotypes potentially showing greater gains in sprint swimming performance.