title: Low back pain and FokI (rs2228570) polymorphism of vitamin D receptor in athletes.
abstract: BACKGROUND
  Low back pain (LBP) is common in athletes. LBP can be detrimental to athletic performance and health. Factors predisposing to LBP in athletes remain elusive and require further studies. We investigated whether carriage of a specific genotype and/or allele of vitamin D receptor gene (VDR) FokI polymorphism (rs2228570) was a risk factor for LBP in athletes of different sports disciplines.
  
  
  METHODS
  This genotype/phenotype association case-control study included 60 Italian athletes (25 females and 35 males; mean age 33.9 ± 13.3 years; body-mass-index 23.5 ± 3.5 kg/m2) of which 16.7% were swimmers, 11.7% soccer players, 11.7% volleyball players, 10.0% rugby players and other disciplines.VDR-FokI polymorphism was measured by PCR-RFLP in 24 athletes with LBP and 36 athletes without LBP episodes. Absence or presence of the FokI restriction site was denoted "F" and "f", respectively. Other risk factors were evaluated by a questionnaire.
  
  
  RESULTS
  The homozygous FF genotype was found in 58.3% (14/24) of athletes with LBP versus 27.8% (10/36) of athletes without LBP, adjusted OR = 5.78, 95% CI 1.41-23.8,P= 0.015. The F allele was a 2-fold risk factor to develop LBP, adjusted OR = 2.55, 95% CI 1.02-6.43, P = 0.046, while f allele was protective. Exposure to vehicle vibrations ≥2 h daily, and family history of lumbar spine pathology were significant risk factors for LBP with OR = 3.54, and OR = 9.21, respectively.
  
  
  CONCLUSIONS
  This is the first study in which an association betweenVDR-FokI polymorphism and LBP in athletes was found. Further research is needed to extend our results, and to clarify the biochemical pathways associated with how vitamin D modulates LBP in athletes. TheVDR-FokI polymorphism should be considered when developing genetic focused studies of precision medicine on health in athletes.
authors.affiliation: Department of Medical and Biological Sciences, School of Medicine, University of Udine, Udine, 33100 Italy.|Clinical Biochemistry and Molecular Biology, Department of Medical and Biological Sciences, Piazzale Kolbe 4, 33100 Udine, Italy.
authors.forename: Sabina
authors.initials: S
authors.lastname: Cauci
authors.affiliation: Department of Medical and Biological Sciences, School of Medicine, University of Udine, Udine, 33100 Italy.|Department of Medicine, Surgery and Health Sciences, School of Medicine, University of Trieste, Trieste, 34100 Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Migliozzi
authors.affiliation: Department of Medical and Biological Sciences, School of Medicine, University of Udine, Udine, 33100 Italy.
authors.forename: Carlo Simone
authors.initials: CS
authors.lastname: Trombetta
authors.affiliation: Department of Medical and Biological Sciences, School of Medicine, University of Udine, Udine, 33100 Italy.
authors.forename: Ilaria
authors.initials: I
authors.lastname: Venuto
authors.affiliation: Department of Experimental and Clinical Medical Sciences, School of Medicine, University of Udine, Udine, 33100 Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Saccheri
authors.affiliation: Department of Experimental and Clinical Medical Sciences, School of Medicine, University of Udine, Udine, 33100 Italy.
authors.forename: Luciana
authors.initials: L
authors.lastname: Travan
authors.affiliation: Department of Medicine, Surgery and Health Sciences, School of Medicine, University of Trieste, Trieste, 34100 Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Chiriacò
keywords: Discopathies; Exercise; Exposure to vibrations; FokI polymorphism; Lumbar pain; Smoking and low back pain; Vitamin D receptor; Vitamin D receptor gene; Vitamin D receptor polymorphism