title: Linkage between a muscle-specific CK gene marker and VO2max in the HERITAGE Family Study.
abstract: OBJECTIVE
  We have reported a significant association between VO2max in the sedentary state and its response (delta VO2max) to an endurance training program with a muscle-specific creatine kinase (CKMM) gene polymorphism. The purpose of this study was to test the hypothesis of genetic linkage between the same CKMM marker and VO2max in the sedentary state as well as delta VO2max.
  
  
  METHODS
  Sib-pair linkage analysis was performed on 277 full sib-pairs from 98 Caucasian nuclear families of the HERITAGE Family Study. VO2max was measured during cycle ergometry tests before and after 20 wk of endurance training. The CKMM polymorphism was detected by the polymerase chain reaction and digestion with the Ncol restriction enzyme.
  
  
  RESULTS
  Frequencies for the rare (1170 base pairs) and common (985 + 185 base pairs) alleles were 0.32 and 0.68, respectively. No significant linkage (t = -0.02, P = 0.49) was detected between the CKMM marker and the age and sex adjusted VO2max (mL x kg(-1) x min(-1)) in the sedentary state. However, after adjustment of delta VO2max for the effects of age, sex, initial VO2max, and body mass, evidence for linkage between the CKMM locus and delta VO2max was suggestive (P = 0.04).
  
  
  CONCLUSIONS
  The present results provide further support for the notion that the CKMM gene, or some gene in close linkage disequilibrium with it, may contribute to individual differences in the VO2max response to endurance training.
authors.affiliation: Department of Social and Preventive Medicine, Laval University, Ste-Foy, Québec, Canada.
authors.forename: M A
authors.initials: MA
authors.lastname: Rivera
authors.forename: L
authors.initials: L
authors.lastname: Pérusse
authors.forename: J A
authors.initials: JA
authors.lastname: Simoneau
authors.forename: J
authors.initials: J
authors.lastname: Gagnon
authors.forename: F T
authors.initials: FT
authors.lastname: Dionne
authors.forename: A S
authors.initials: AS
authors.lastname: Leon
authors.forename: J S
authors.initials: JS
authors.lastname: Skinner
authors.forename: J H
authors.initials: JH
authors.lastname: Wilmore
authors.forename: M
authors.initials: M
authors.lastname: Province
authors.forename: D C
authors.initials: DC
authors.lastname: Rao
authors.forename: C
authors.initials: C
authors.lastname: Bouchard
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003402:Creatine Kinase / Q000378:metabolism*; D015444:Exercise / Q000502:physiology*; D008040:Genetic Linkage / Q000235:genetics*; D005819:Genetic Markers; D006801:Humans; D008875:Middle Aged; D010101:Oxygen Consumption / Q000502:physiology*; D010807:Physical Endurance / Q000502:physiology*; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D015656:Respiratory Mechanics / Q000502:physiology*
chemical_list: D005819:Genetic Markers; D003402:Creatine Kinase