If you have a family history of rheumatoid arthritis or osteoarthritis you may feel concern regarding any possible genetic factor in these illnesses. Can we determine from the literature what genetic determinants exist for RA and osteoarthritis, and what level of risk they present?
What is arthritis, and is it hereditary?
If you have a family history of arthritis, you may feel concern about the possibility of a genetic component to this chronic illness. Watching family members struggle with symptoms such as inflammation, pain, stiffness and loss of mobility is enough to make anyone worry about what the future may hold. But is there any necessity for such concern?
Arthritis is often classified into three main categories, rheumatoid arthritis, osteoarthritis and gout.1 The causes of osteoarthritis are usually summed up as 'wear and tear' but 'wear and repair' is closer to what actually takes place in the disorder.2 Rheumatoid arthritis, however, is an inflammatory disorder of the immune response, resulting in inflammation of the joint linings and tendons and other symptoms including fatigue.3
Can your genes put you at risk for developing arthritis?
But how concerned should you be if there is a history of arthritis in your immediate or extended family? Is your genetic history your destiny? Is the grinding of the machinery of transcription and translation inexorable? Not automatically, it seems: certain genes may 'increase the likelihood' of developing rheumatoid arthritis, but do not have complete penetrance i.e. possession of a particular gene does not automatically mean you will develop RA.3
How much of a factor is genetics in arthritis? Rheumatoid arthritis is believed to have a strong genetic component and 'does seem to run in families'.3 Official documentation from the UK National Health Service gives a percentage of 40-60% of certain types of osteoarthritis having a genetic component2, while possession of two copies of a particular gene is described as resulting in 'a 60% increased risk for RA'.4 It seems that more than one gene is involved in the transmission of RA.3
How does this affect treatments?
If genetic history is in fact significant in the development of arthritis, can other factors ameliorate or aggravate the course of the disease? Nutritional supplements such as chondroitin have been used as complementary treatments by some people.5 Exercise is important for osteoarthritis, especially after surgery,1 while alternative and complementary therapies including massage, acupuncture and hydrotherapy have their proponents.5 Obesity on the other hand may aggravate osteoarthritis.2
Are treatments for arthritis affected by suggestions of a genetic component? Gene therapy for RA was recently described as in the early stages regarding human trials7, while a January 2009 article in http://www.bio-medicine.org/ reviewed 'the first clinical evidence' of positive results of gene therapy for RA in humans.8 It has been described as 'too early to say' whether the Stat4 genetic pathway might reveal significant new avenues for RA treatment.4
What can you do about it?
Even if your genes may put you at increased risk of arthritis, is there anything you can do to improve an existing condition or reduce your risk of developing it in the first place? Rapid treatment of arthritis soon after onset of the disease is very important and may reduce the damage resulting from disease progression.5 Treatments fall into the categories of analgesics, NSAIDS (non-steroidal anti-inflammatory drugs), DMARDS (disease-modifying, anti-rheumatic drugs), biologicals and corticosteroids.3
What testing is available to determine the presence of arthritis? There is no infallible test: instead a 'clinical diagnosis' is made on the basis of a patient's symptoms and history. Blood tests and X-rays may assist with this process.3
Focussing on treatments, tactics and lifestyle choices – i.e. effective disease management, may be more useful than anxiety about what your genes may have in store regarding arthritic conditions.
1 NHS Choices. “Treating Joint Pain". www.direct.gov.uk 03/03/2008 (15/08/2009) <http://www.nhs.uk/Livewell/Pain/Pages/Jointpain.aspx>2 NHS Choices. “Causes of osteoarthritis." www.direct.gov.uk 03/08/2009 (15/08/2009) <http://www.nhs.uk/Conditions/Osteoarthritis/Pages/Causes.aspx>3 Arthritis Research Campaign. “Rheumatoid Arthritis." http://www.arc.org.uk June 2006 (15/08/2009) <http://www.arc.org.uk/arthinfo/patpubs/6033/6033.asp>4 Remmers E, et al. “STAT4 and the risk of rheumatoid arthritis and systemic lupus erythematosus." NEJM 2007;357(10):13-22.5 NHS Choices “Treating arthritis.". http://www.nhs.uk 05/08/2008 (15/08/2009) <http://www.nhs.uk/Conditions/Arthritis/Pages/Treatment.aspx> 6 Evans, C.H., & PD Robbins “Gene therapy for arthritis.“ Expert Opinion on Investigational Drugs July 1997, Vol. 6, No. 7, Pages 837-840 7 James M Woods, Yasmin Sitabkhan, Alisa E Koch “Gene therapy for rheumatoid arthritis: recent advances." Current gene therapy. 01/03/2008; 8(1):24-41.8 Prescott, B. “Gene therapy demonstrates benefit in patients with rheumatoid arthritis." http://www.bio-medicine.org 26/01/2009. (15/08/2009) <http://www.bio-medicine.org/biology-news-1/Gene-therapy-demonstrates-benefit-in-patients-with-rheumatoid-arthritis-6782-1/>