Article Text

PDF
A pathway-based approach investigating the genes encoding interleukin-1β, interleukin-6 and the interleukin-1 receptor antagonist provides new insight into the genetic susceptibility of Achilles tendinopathy
  1. Alison V September1,2,
  2. Erica-Mari Nell1,
  3. Kevin O'Connell1,
  4. Jill Cook3,
  5. Christopher J Handley4,
  6. Lize van der Merwe1,5,6,
  7. Martin Schwellnus1,2,
  8. Malcolm Collins1,2,7
  1. 1MRC/UCT Research Unit for Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa
  2. 2International Olympic Committee (IOC) Research Centre, Cape Town, South Africa
  3. 3School of Primary Health Care, Faculty of Medicine, Nursing and Health Sciences, Monash University, Victoria 3800, Australia
  4. 4School of Human Biosciences and the Musculoskeletal Research Centre, La Trobe University, Melbourne, Australia
  5. 5Biostatistics Unit, South African Medical Research Council, Cape Town, South Africa
  6. 6Department of Statistics, University of Western Cape, Cape Town, South Africa
  7. 7MRC/UCT Research Unit for Exercise Science and Sports Medicine, South African Medical Research Council, Cape Town, South Africa
  1. Correspondence to Alison V September, UCT/MRC Unit for Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa; Alison.September{at}uct.ac.za

Abstract

Objectives Achilles tendinopathy (AT) is a multifactorial condition for which genetic risk factors have been identified. A pathway-based approach was used to investigate genes within the inflammatory pathway.

Methods Functional polymorphisms within IL-1β (−31T→C and −511C→T), IL-1RN (variable number tandem repeat) and IL-6 (−172G→C) were investigated for associations with AT in a South African (SA) and Australian (AUS) case–control studies. A total of 369 (161 SA and 208 AUS) asymptomatic control participants (CON) and 175 (90 SA and 85 AUS) participants with AT (TEN) were genotyped. Allele combinations were constructed using the above polymorphisms in combination with the COL5A1 BstUI RFLP.

Results Independently, no associations were observed between any of the polymorphisms tested and risk of TEN. The allele combinations of five polymorphisms were, however, found to have a highly significant relationship with AT (p=0.005), after adjusting for gender and country (SA or AUS).

Conclusions Variations within the interleukin genes and the COL5A1 BstUI CC genotype are collectively significantly associated with risk of AT. This research emphasises that a pathway-based genetic association study may be a more effective approach to capture and understand the genetic risk factors underlying the multifactorial conditions, such as AT.

Statistics from Altmetric.com

Footnotes

  • EN and KO'C contributed equally to this work

  • Funding This study was supported in part by funds from the National Research Foundation (grant numbers SUR2008060500012 and FA2005021700015), the South African Medical Research Council, the University of Cape Town and Discovery Health. The final preparation of this study for publication was supported in part by the International Olympic Committee (IOC) Research grant to the Clinical Sports Medicine Group of the UCT/MRC Research Unit for Exercise Science and Sports Medicine of the University of Cape Town. The authors, EN and KO'C, were awarded the grantholder-linked student support from the National Research Foundation (NRF) of South Africa (Grant SUR2008060500012).

  • Competing interests None.

  • Patient consent Obtained.

  • Ethics approval This study was conducted with the approval of the University of Cape Town, and the University of La Trobe and Deakin University

  • Provenance and peer review Not commissioned; externally peer reviewed.

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.