November 1, 2007Medicine & Science in Sports & Exercise142 citations
View Full PaperThe ACTN3 R577X Polymorphism in East and West African Athletes
Key Result
The ACTN3 R577X polymorphism (alpha-actinin-3 deficiency) is not a major influence on endurance or sprint performance in African athletes.
Study Design
Type
Case-Control (n=838)
Multicenter
Yes
Structured PICO
Does the ACTN3 R577X polymorphism influence the success of elite African athletes?
P
Population
838 elite African athletes and controls from Ethiopia, Kenya, and Nigeria genotyped to assess the influence of the ACTN3 R577X polymorphism on athletic performance.
E
Exposure
Elite athletic status (endurance or power/sprint)
C
Comparator
Non-athlete controls from the same populations
O
Outcome
Frequency of the ACTN3 R577X polymorphism (functional R allele and nonfunctional X allele)surrogate
Alpha-actinin-3 deficiency (ACTN3 R577X polymorphism) does not appear to be a major genetic factor influencing the performance of elite African endurance or power athletes.
Limitations
- The low baseline frequencies of the X allele in the tested populations mean that any associations with sprint performance would likely be obscured.
Abstract
PURPOSE: To determine the frequency of the ACTN3 R577X polymorphism (functional R allele and nonfunctional X allele) in a variety of African populations and to examine its influence on the success of elite East African endurance runners and West African sprinters. METHODS: The R577X polymorphism was genotyped in 198 Ethiopian controls and 76 elite Ethiopian endurance athletes, 158 Kenyan controls and 284 elite Kenyan endurance runners, and 60 Nigerian controls and 62 elite Nigerian power athletes. Statistical analyses were performed by exact tests of population differentiation, using Arlequin, version 3. Analyses were carried out using 1 x 10(6) Markov chain steps, and 1 x 10(5) dememorization steps. RESULTS: The frequency of the X allele was extremely low among Kenyans and Nigerians (approximately 1% homozygosity) and higher in Ethiopians (approximately 11% homozygosity). The low baseline frequencies of the three populations tested mean that any associations with sprint performance would likely be obscured. In Ethiopians, where baseline levels of 577XX were about 11%, there was no increased frequency in the endurance athletes. CONCLUSION: Our data suggest that alpha-actinin-3 deficiency is not a major influence on performance in African athletes.
Cite This Study
Yang et al. (Thu,) conducted a case-control in Elite athletic performance (n=838). ACTN3 R577X polymorphism vs. Controls was evaluated on Frequency of the ACTN3 R577X polymorphism. The ACTN3 R577X polymorphism (alpha-actinin-3 deficiency) is not a major influence on endurance or sprint performance in African athletes.