title: A variant within the AQP1 3'-untranslated region is associated with running performance, but not weight changes, during an Ironman Triathlon.
abstract: The objective of this study was to test the association of the rs1049305 (G > C) variant within the 3'-untranslated region of the aquaporin 1 gene, AQP1, with changes in body weight, post-race serum sodium concentration and performance in Ironman triathletes. Five hundred and four male Ironman triathletes were genotyped for the rs1049305 variant within the AQP1 gene. Change in pre- and post-race body weight was calculated for 470 triathletes and used as a proxy for changes in body fluid during the race, as well as to divide triathletes into biologically relevant weight-loss groups (0-3%, 3-5% and >5%). There were no rs1049305 genotype effects on post-race serum sodium concentrations (P = 0.647), pre-race weight (P = 0.610) nor relative weight change during the Ironman Triathlons (P = 0.705). In addition, there were no significant differences in genotype (P = 0.640) nor allele (P = 0.643) distributions between the weight loss groups. However, triathletes who carry a C-allele were found to complete the 42.2-km run stage faster (mean 286, s = 49 min) than triathletes with a GG genotype (mean 296, s = 47 min; P = 0.032). The AQP1 rs1049305 variant is associated with running performance, but not relative body weight change, during the 2000, 2001 and 2006 South African Ironman Triathlons.
authors.affiliation: a MRC/UCT Research Unit for Exercise Science and Sports Medicine of the Department of Human Biology, Faculty of Health Sciences , University of Cape Town, South Africa and the South African Medical Research Council , Cape Town , South Africa.
authors.forename: Colleen J
authors.initials: CJ
authors.lastname: Saunders
authors.forename: Michael
authors.initials: M
authors.lastname: Posthumus
authors.forename: Kevin
authors.initials: K
authors.lastname: O'Connell
authors.forename: Alison V
authors.initials: AV
authors.lastname: September
authors.forename: Malcolm
authors.initials: M
authors.lastname: Collins
mesh_terms: D020413:3' Untranslated Regions; D000328:Adult; D051398:Aquaporin 1 / Q000235:genetics*; D001642:Bicycling / Q000502:physiology*; D005838:Genotype; D006801:Humans; D008297:Male; D010807:Physical Endurance / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D012420:Running / Q000502:physiology*; D012964:Sodium / Q000097:blood; D013550:Swimming / Q000502:physiology*; D015431:Weight Loss / Q000235:genetics*
chemical_list: D020413:3' Untranslated Regions; C496020:AQP1 protein, human; D051398:Aquaporin 1; D012964:Sodium
keywords: aquaporin 1; athletic performance; body fluids; water channel proteins