European Journal of Human Genetics (2005) 13, 965–969. doi:10.1038/sj.ejhg.5201438; published online 11 May 2005

Mitochondrial DNA and ACTN3 genotypes in Finnish elite endurance and sprint athletes

Anna-Kaisa Niemi1,2 and Kari Majamaa1,2

  1. 1Department of Neurology, University of Oulu, Oulu, Finland
  2. 2Clinical Research Center, Oulu University Hospital, Oulu, Finland

Correspondence: Professor K Majamaa, Department of Neurology, University of Oulu, PO Box 5000, FIN-90014 Oulu, Finland. Tel: +358 8 315 4526; Fax: +358 8 315 4544; E-mail:

Received 9 December 2004; Revised 21 March 2005; Accepted 12 April 2005; Published online 11 May 2005.



Differences in ACTN3 (alpha-actinin 3) genotypes have been reported among endurance and power athletes. Elite athletic performance in endurance sports should also depend on mitochondrial oxidative phosphorylation (OXPHOS) that produces ATP for muscle metabolism. We determined mitochondrial DNA (mtDNA) and ACTN3 genotypes in Finnish elite endurance (n=52) and sprint (n=89) athletes, and found that the frequencies of mtDNA haplogroups differed significantly between the two groups. Most notably, none of the endurance athletes belonged to haplogroup K or subhaplogroup J2, both of which have previously been associated with longevity. The frequency of ACTN3 XX genotype was higher and that of RR was lower among Finnish endurance athletes, and, in addition, none of the top Finnish sprinters had the XX genotype. Lack of mtDNA haplogroup K and subhaplogroup J2 among elite endurance athletes suggests that these haplogroups are 'uncoupling genomes'. Such genomes should not be beneficial to endurance-type athletic performance but should be beneficial to longevity, since uncoupling of OXPHOS reduces the production of ATP, reduces the release of reactive oxygen species and generates heat.


physical endurance, genetics, longevity