title: BsmI polymorphism in the vitamin D receptor gene is associated with leg extensor muscle strength in elderly men.
abstract: OBJECTIVE
  Sarcopenia is defined as a reduction in skeletal muscle mass, strength, and endurance observed with advancing age. Although Vitamin D receptor (VDR) polymorphism is reported to be associated with muscle mass and strength, evidence for this is limited and conflicting. In this study, we examined the association between the polymorphisms of VDR gene BsmI, TaqI and FokI and muscular mass and strength in elderly men.
  
  
  METHODS
  This is a cross-sectional study conducted in a university hospital. One hundred and twenty men over 65 years of age participated, all participants were active men living independently in Istanbul, who were followed as outpatients in geriatric polyclinics. Most common diagnoses were hypertension, hyperlipidemia, and mild to moderate osteoarthritis. Morbid obese patients were not included in the study. Genomic DNA was extracted from peripheral blood, and VDR genotypes were determined by the polymerase chain reaction. The peak torque of the knee flexors and extensors was measured on a Cybex 350 dynamometer. Body muscle mass was calculated by using bioelectric impedance analysis.
  
  
  RESULTS
  The extensor strength of the knee was higher in BB homozygotic men than in the Bb/bb group. No significant association was found with TaqI and FokI haplotypes. There was no significant association between muscle mass and strength, or between muscle mass and VDR genotype.
  
  
  CONCLUSIONS
  Our data suggest that VDR gene BsmI polymorphism is associated with muscular strength in elderly men.
authors.affiliation: Department of Internal Medicine, Istanbul Medical School, Istanbul University, Istanbul, Turkey. gbahatozturk@yahoo.com
authors.forename: Gulistan
authors.initials: G
authors.lastname: Bahat
authors.forename: Bulent
authors.initials: B
authors.lastname: Saka
authors.forename: Nilgun
authors.initials: N
authors.lastname: Erten
authors.forename: Ugur
authors.initials: U
authors.lastname: Ozbek
authors.forename: Ender
authors.initials: E
authors.lastname: Coskunpinar
authors.forename: Safinaz
authors.initials: S
authors.lastname: Yildiz
authors.forename: Turker
authors.initials: T
authors.lastname: Sahinkaya
authors.forename: Mehmet Akif
authors.initials: MA
authors.lastname: Karan
mesh_terms: D000368:Aged; D000375:Aging / Q000235:genetics* / Q000502:physiology; D001823:Body Composition; D003430:Cross-Sectional Studies; D005838:Genotype; D006801:Humans; D007719:Knee Joint / Q000502:physiology; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D053580:Muscle Strength / Q000235:genetics*; D010807:Physical Endurance / Q000502:physiology; D011110:Polymorphism, Genetic; D018167:Receptors, Calcitriol / Q000235:genetics*; D055948:Sarcopenia / Q000235:genetics* / Q000503:physiopathology
chemical_list: D018167:Receptors, Calcitriol