title: The ACTN3 XX genotype's underrepresentation in Japanese elite wrestlers.
abstract: OBJECTIVE
  To examine the relationship between ACTN3 polymorphisms and level of athletic performance in Japanese wrestlers.
  
  
  METHODS
  The control group consisted of 243 healthy Japanese individuals. The authors divided 135 wrestlers into 3 groups based on their results in national or international competitions. They classified as elite 24 wrestlers who had placed in the top 8 in a world championship or participated in Olympic games, 28 wrestlers who had participated in world championships or become champions in Japan's national championships were classified as subelite, and 83 wrestlers were classified as national (N-W, ie, national-level wrestler). In addition, the authors combined the elite and subelite to form the classification international-level wrestlers (I-W).
  
  
  RESULTS
  The frequency of the null X allele and the XX genotype were significantly lower in the I-W group than in the control group. However, there was no significant difference in ACTN3 genotype or allele frequency between the N-W and control groups. The frequency of the ACTN3 XX genotype in the elite groups was lower than that of all groups, and a linear tendency was observed between ACTN3 XX genotype and athletic status.
  
  
  CONCLUSIONS
  In conclusion, the data indicated that ACTN3 polymorphisms were related to athletic performance in Japanese wrestlers.
authors.affiliation: Graduate School of Health and Sport Science, the Laboratory of Sports Nutrition, Nippon Sport Science University, Tokyo, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Kikuchi
authors.forename: Dai
authors.initials: D
authors.lastname: Ueda
authors.forename: Seok-ki
authors.initials: SK
authors.lastname: Min
authors.forename: Koichi
authors.initials: K
authors.lastname: Nakazato
authors.forename: Shoji
authors.initials: S
authors.lastname: Igawa
mesh_terms: D000185:Actinin / Q000235:genetics*; D000483:Alleles; D054874:Athletic Performance / Q000502:physiology*; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D005260:Female; D005838:Genotype; D006801:Humans; D007564:Japan; D008297:Male; D020641:Polymorphism, Single Nucleotide; D014952:Wrestling / Q000502:physiology*; D055815:Young Adult
chemical_list: C118456:ACTN3 protein, human; D000185:Actinin