Purinergic Signalling

, Volume 12, Issue 1, pp 103–113 | Cite as

Functional polymorphisms in the P2X7 receptor gene are associated with stress fracture injury

  • Ian Varley
  • Julie P. GreevesEmail author
  • Craig Sale
  • Eitan Friedman
  • Daniel S. Moran
  • Ran Yanovich
  • Peter J. Wilson
  • Alison Gartland
  • David C. Hughes
  • Trent Stellingwerff
  • Craig Ranson
  • William D. Fraser
  • James A. Gallagher
Original Article


Military recruits and elite athletes are susceptible to stress fracture injuries. Genetic predisposition has been postulated to have a role in their development. The P2X7 receptor (P2X7R) gene, a key regulator of bone remodelling, is a genetic candidate that may contribute to stress fracture predisposition. The aim of this study is to evaluate the putative contribution of P2X7R to stress fracture injury in two separate cohorts, military personnel and elite athletes. In 210 Israeli Defense Forces (IDF) military conscripts, stress fracture injury was diagnosed (n = 43) based on symptoms and a positive bone scan. In a separate cohort of 518 elite athletes, self-reported medical imaging scan-certified stress fracture injuries were recorded (n = 125). Non-stress fracture controls were identified from these cohorts who had a normal bone scan or no history or symptoms of stress fracture injury. Study participants were genotyped for functional SNPs within the P2X7R gene using proprietary fluorescence-based competitive allele-specific PCR assay. Pearson’s chi-squared (χ 2) tests, corrected for multiple comparisons, were used to assess associations in genotype frequencies. The variant allele of P2X7R SNP rs3751143 (Glu496Ala—loss of function) was associated with stress fracture injury, whilst the variant allele of rs1718119 (Ala348Thr—gain of function) was associated with a reduced occurrence of stress fracture injury in military conscripts (P < 0.05). The association of the variant allele of rs3751143 with stress fractures was replicated in elite athletes (P < 0.05), whereas the variant allele of rs1718119 was also associated with reduced multiple stress fracture cases in elite athletes (P < 0.05). The association between independent P2X7R polymorphisms with stress fracture prevalence supports the role of a genetic predisposition in the development of stress fracture injury.


P2X7 receptor Bone Stress fracture injury 



We are grateful to all participants for taking part in the study.

Disclosure statement

The authors have nothing to disclose.


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Copyright information

© Her Majesty the Queen in Right of United Kingdom 2016

Authors and Affiliations

  • Ian Varley
    • 1
  • Julie P. Greeves
    • 2
    Email author
  • Craig Sale
    • 1
  • Eitan Friedman
    • 3
  • Daniel S. Moran
    • 4
  • Ran Yanovich
    • 4
  • Peter J. Wilson
    • 5
  • Alison Gartland
    • 6
  • David C. Hughes
    • 1
  • Trent Stellingwerff
    • 7
  • Craig Ranson
    • 8
  • William D. Fraser
    • 9
    • 10
  • James A. Gallagher
    • 5
  1. 1.Musculoskeletal Physiology Research Group, Sport, Health and Performance Enhancement Research CentreNottingham Trent UniversityNottinghamUK
  2. 2.Department of Occupational MedicineHeadquarters Army Recruiting and Training DivisionPewseyUK
  3. 3.The Susanne Levy Gertner Oncogenetics UnitSheba Medical CenterTel-HashomerIsrael
  4. 4.Ariel and Heller Institue, Sheba Medical CenterAriel UniversityRamat GenIsrael
  5. 5.Bone and Joint Research Group, Department of Musculoskeletal Biology, Institute of Ageing and Chronic Diseases, Faculty of Health and Life SciencesUniversity of LiverpoolLiverpoolUK
  6. 6.The Mellanby Centre for Bone Research, Department of Human MetabolismThe University of SheffieldSheffieldUK
  7. 7.Canadian Sport Institute PacificPacific Institute for Sport ExcellenceVictoriaCanada
  8. 8.Cardiff School of SportCardiff Metropolitan UniversityCardiffUK
  9. 9.Norwich Medical SchoolUniversity of East AngliaNorwichUK
  10. 10.Norfolk and Norwich University HospitalNorfolkUK

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