The ACTN3 R577X polymorphism in East and West African athletes.
OBJECTIVE
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.


CONCLUSIONS
Our data suggest that alpha-actinin-3 deficiency is not a major influence on performance in African athletes.
Yang
Nan
N
Institute for Neuromuscular Research, Children's Hospital at Westmead, Sydney, Australia.
MacArthur
Daniel G
DG
Wolde
Bezabhe
B
Onywera
Vincent O
VO
Boit
Michael K
MK
Lau
Sau Yin Mary-Ann
SY
Wilson
Richard H
RH
Scott
Robert A
RA
Pitsiladis
Yannis P
YP
North
Kathryn
K
D000185:Actinin / Q000235:genetics*; D000351:Africa, Eastern; D000354:Africa, Western; D000483:Alleles; D041321:Chromosomes, Human, X; D005787:Gene Frequency; D006801:Humans; D008390:Markov Chains; D011110:Polymorphism, Genetic; D013177:Sports
C118456:ACTN3 protein, human; D000185:Actinin