title: The ACTN3 R577X polymorphism in East and West African athletes.
abstract: 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.
authors.affiliation: Institute for Neuromuscular Research, Children's Hospital at Westmead, Sydney, Australia.
authors.forename: Nan
authors.initials: N
authors.lastname: Yang
authors.forename: Daniel G
authors.initials: DG
authors.lastname: MacArthur
authors.forename: Bezabhe
authors.initials: B
authors.lastname: Wolde
authors.forename: Vincent O
authors.initials: VO
authors.lastname: Onywera
authors.forename: Michael K
authors.initials: MK
authors.lastname: Boit
authors.forename: Sau Yin Mary-Ann
authors.initials: SY
authors.lastname: Lau
authors.forename: Richard H
authors.initials: RH
authors.lastname: Wilson
authors.forename: Robert A
authors.initials: RA
authors.lastname: Scott
authors.forename: Yannis P
authors.initials: YP
authors.lastname: Pitsiladis
authors.forename: Kathryn
authors.initials: K
authors.lastname: North
mesh_terms: 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
chemical_list: C118456:ACTN3 protein, human; D000185:Actinin