By Dr. Lynn Webster, PNN Columnist
Millions of Americans order DNA test kits to determine their ancestries. Knowing where you come from can be entertaining. However, DNA testing can also help identify your risk of developing some diseases, including chronic pain.
Prenatal testing for genetic disorders is common. But genetic testing is also increasingly used to determine the risk of developing certain diseases or potential responses to specific drugs.
Currently, little is known about how to use genes to make an individual more or less sensitive to pain, or to learn the likelihood that someone will respond in a particular way to an analgesic based on their genetics. The good news is that we are on the cusp of gaining more information about the genes that control pain and pain treatments, and that knowledge should allow us to develop targeted pain therapies.
Most physicians still believe that everyone experiences pain in the same way. Research recently published in Current Biology discovered a genethe so-called "Neanderthal gene"that is associated with increased sensitivity to pain. Recognizing that a mutation of a specific gene can influence pain perception may be illuminating for many members of the medical profession.
Pain specialists have known for a long time that given the same stimulus, some people feel more pain than others. The truth is, there are several genes besides the Neanderthal gene that determine how an individual experiences pain. Some genes increase our sensitivity to pain, while other genes decrease it. Some genes influence how pain is processed, while other genes determine an individual's response to an analgesic.
The ability for an analgesic to provide pain relief in an individual is partially determined by the genetics of the receptor to which the pain medication binds. These genes are different from pain-sensitivity genes. For example, oxycodone may be very effective in relieving pain for one individual, but only partially effective for another.
Optimal pain relief requires recognition that each individual responds uniquely to a given analgesic. Doctors are beginning to provide gene therapy for cancer patients. Advancements in research may someday allow us to do the same for patients with pain.
The array of pain responses to the same stimulus is a major reason why one-size-fits-all dosing of pain medications is flawed. A given dose may leave some patients undertreated and others over-treated. Unfortunately, regulators who set arbitrary dose limits fail to understand or consider this biologic variability.
Differing clinical responses to pain stimuli and medications underscore the need to individualize therapy. Knowing more about the biology of pain can help us to understand each individuals response to painful stimuli and the variable response to any therapy.
How we experience pain is a result of both environmental and genetic features. The genetic factors are what we inherit. Environmental factors which we develop rather than inherit include cultural attitudes, emotions, and individual responses to stress. Our personality and lifes experiences are included in the environmental factors that contribute to our experience of pain. Therefore, pain is a result of genetic and environmental interactions. Both can make an individual more or less sensitive to stimuli or analgesia. It is a complex and dynamic process.
The so-called Neanderthal gene is not a new discovery but was newly recognized in Neanderthals. The discovery is interesting, because it implies the gene has an evolutionary purpose. The gene is known as SCN9. There are several pain syndromes associated with the genetic mutations of the SCN9 gene, including some types of back pain and sciatica. Mutations of this gene can result in the total absence of pain or a heightened pain expression. The type of mutation determines the phenotype (or personal characteristics) of our response to a painful stimulus.
It is unclear how Neanderthals benefited biologically from increased pain sensitivity. As we know, acute pain elicits an alarm and is considered protective. It teaches us to avoid dangers that can threaten our life, and prevents us from walking on a broken leg until it heals sufficiently to bear our weight.
Evolution may not have been concerned about the effects of chronic pain. The Neanderthals' limited life expectancy, and the fact that their survival depended on strong physical conditioning, may have made chronic pain a non-issue. Chronic pain may have made survival difficult, or even impossible, for the Neanderthals.
The recent discovery that Neanderthals had the SCN9 gene should not be surprising, given the fact that modern humans shared a common ancestor with Neanderthals. The Neanderthal gene study is of particular interest to me, because I am working with several companies that are exploring potential drugs to affect the function of the SCN9 gene. The companies have different approaches, but they all are trying to find a way to dial down an individual's sensitivity to painful stimuli.
Since the SCN9 gene can be responsible for the total absence of all pain, as well as several extreme forms of pain, it may be reasonable to target the SCN9 gene to modulate pain.
My hope is that manipulation of the SCN9 gene will reduce pain sensitivity, making it easier to control pain by adjusting the dose and type of drug we prescribe.
It is possible one or more drugs that target the SCN9 gene will be available within the next 4-6 years. If that occurs, it could be game changer for people in pain. We can then thank our Neanderthal ancestors for the evolutionary gift.
Lynn R. Webster, MD, is a vice president of scientific affairs for PRA Health Sciences and consults with the pharmaceutical industry. He is author of the award-winning book, The Painful Truth, and co-producer of the documentary, It Hurts Until You Die. You can find Lynn on Twitter: @LynnRWebsterMD
More here:
Genetic Studies Could Pave the Way to New Pain Treatments - Pain News Network
- About the Gene Therapy Review - November 8th, 2009 [November 8th, 2009]
- Contribute an Article - November 8th, 2009 [November 8th, 2009]
- EBSCO Publishing Deal - November 8th, 2009 [November 8th, 2009]
- Advertising Opportunities - November 8th, 2009 [November 8th, 2009]
- Instructions for Authors - November 8th, 2009 [November 8th, 2009]
- Isis Collaboration With Ortho-McNeil Inc for Metabolic Diseases - November 8th, 2009 [November 8th, 2009]
- Dystrophin Gene Transfer safe in Duchenne muscular dystrophy - November 8th, 2009 [November 8th, 2009]
- Researchers Identify Gene for Rare Form of Spinal Muscular Atrophy - November 8th, 2009 [November 8th, 2009]
- Fatal brain cancer tamed by New gene therapy - November 8th, 2009 [November 8th, 2009]
- Gene therapy effective in fighting obesity in mice - November 8th, 2009 [November 8th, 2009]
- Genzyme gene therapy for people with peripheral artery disease failed in a clinical trial to help them regain some mobility - November 8th, 2009 [November 8th, 2009]
- Gene Therapy May Stall Inherited Emphysema - December 31st, 2009 [December 31st, 2009]
- Gene Therapy and Stem Cells Save Limb - December 31st, 2009 [December 31st, 2009]
- TNVitamins.com – $10 Off Of $50 order - May 7th, 2011 [May 7th, 2011]
- 15% Off Any PetAlive Order - May 7th, 2011 [May 7th, 2011]
- At PetAlive – $10 off order of $50 or more - May 7th, 2011 [May 7th, 2011]
- Native Remedies coupon – 5% Off Any Order - May 7th, 2011 [May 7th, 2011]
- Native Remedies – Save $5 coupon - May 7th, 2011 [May 7th, 2011]
- Welcome to the Gene Therapy Review - May 15th, 2011 [May 15th, 2011]
- Editorial Board - May 15th, 2011 [May 15th, 2011]
- Gene Therapy Job Board - May 15th, 2011 [May 15th, 2011]
- Corporate Membership - May 22nd, 2011 [May 22nd, 2011]
- Native Remedies coupon – 25% Off Any Order - May 29th, 2011 [May 29th, 2011]
- What is Gene Therapy? - June 19th, 2011 [June 19th, 2011]
- Research and Markets: Recent Advances in Cancer Research and Therapy - Increased Research on one of the Major Causes ... - April 25th, 2012 [April 25th, 2012]
- Gene Therapy part 2 - Video - April 30th, 2012 [April 30th, 2012]
- Gene therapy reverses Parkinson's symptoms: study - Video - April 30th, 2012 [April 30th, 2012]
- CBS This Morning - Gene therapy reverses Parkinson's symptoms: study - Video - April 30th, 2012 [April 30th, 2012]
- Engineering adenoviruses for gene therapy - Video - April 30th, 2012 [April 30th, 2012]
- What is Gene Therapy (The General Explains) - Video - April 30th, 2012 [April 30th, 2012]
- What is Gene Therapy - Animation - Video - April 30th, 2012 [April 30th, 2012]
- Microbiology Gene Therapy - Video - April 30th, 2012 [April 30th, 2012]
- Gene Therapy in Detail - Video - April 30th, 2012 [April 30th, 2012]
- Breakthrough in Haemophilia treatment - Video - April 30th, 2012 [April 30th, 2012]
- Virology Seminar - Gene Therapy - April 30th, 2012 [April 30th, 2012]
- Gene Therapy Video - Video - April 30th, 2012 [April 30th, 2012]
- Study: Gene Therapy for HIV Safe, But Effectiveness Still Unclear - May 4th, 2012 [May 4th, 2012]
- Gene Therapy Safe in Decade-Long HIV Study That May Widen Use - May 4th, 2012 [May 4th, 2012]
- Gene therapy for HIV safe, but effectiveness still unclear - May 4th, 2012 [May 4th, 2012]
- A Step Forward For Gene Therapy To Treat HIV - May 4th, 2012 [May 4th, 2012]
- A Media Event on Clinical Developments in Gene and Cell Therapy - May 4th, 2012 [May 4th, 2012]
- Families of SMA Awards New Funding to Advance a CNS Delivered Gene Therapy for Spinal Muscular Atrophy - May 4th, 2012 [May 4th, 2012]
- AIDS gene therapy safe -- is it a "cure"? - May 4th, 2012 [May 4th, 2012]
- Generational Achievements in Gene and Cell Therapy Honored at ASGCT 15th Annual Meeting - May 5th, 2012 [May 5th, 2012]
- Lewis speaks on gene therapy at Lexington Community Education event - May 7th, 2012 [May 7th, 2012]
- Penn researchers report a gene-therapy success - May 10th, 2012 [May 10th, 2012]
- Gene therapy for hearing loss: Potential and limitations - May 13th, 2012 [May 13th, 2012]
- Gene therapy extends mouse lifespan by 24 pc - May 16th, 2012 [May 16th, 2012]
- Gene therapy dramatically extends mouse lifespan - May 16th, 2012 [May 16th, 2012]
- Gene therapy may extend life: Study - May 16th, 2012 [May 16th, 2012]
- First gene therapy successful against aging-associated decline: Mouse lifespan extended up to 24% with a single ... - May 16th, 2012 [May 16th, 2012]
- Gene Therapy Extends Mouse Lifespan - May 16th, 2012 [May 16th, 2012]
- Gene Therapy for Brain Disease - May 17th, 2012 [May 17th, 2012]
- Children with rare, incurable brain disease improve after gene therapy - May 17th, 2012 [May 17th, 2012]
- FIRST Anti-Aging Gene Therapy (Brainstorm Ep72) - Video - May 23rd, 2012 [May 23rd, 2012]
- Gene therapy can correct forms of severe combined immunodeficiency - May 25th, 2012 [May 25th, 2012]
- RetroSense Therapeutics Completes pre-IND Meeting for RST-001 - May 25th, 2012 [May 25th, 2012]
- Gene therapy can correct forms of severe combined immunodeficiency, study suggests - May 26th, 2012 [May 26th, 2012]
- Alliance for Cancer Gene Therapy celebrates 10 years - May 29th, 2012 [May 29th, 2012]
- Research on gene therapy by Prasad Eye - June 1st, 2012 [June 1st, 2012]
- Baxter Announces Collaboration with Chatham Therapeutics for Factor IX Hemophilia B Gene Therapy Treatment - June 5th, 2012 [June 5th, 2012]
- Transgenomic Launches Breakthrough Blood-Based Cancer Gene Testing Technology at 2012 ASCO Annual Meeting - June 5th, 2012 [June 5th, 2012]
- Baxter Inks Deal with Chatham - June 6th, 2012 [June 6th, 2012]
- PIK3CA Gene Patent for Predicting Response to Targeted Therapy Issued – Exclusively Licensed to Transgenomic - June 11th, 2012 [June 11th, 2012]
- SalutarisMD Announces Positive Case Report of a New Investigational Wet AMD Therapy at ARVO - June 15th, 2012 [June 15th, 2012]
- Research and Markets: Gene Therapy - Global Strategic Business Report - 2012 - June 15th, 2012 [June 15th, 2012]
- New York Law Firm’s MesotheliomaHelp.net Site Publishes Interview with Gene Therapy Author - June 17th, 2012 [June 17th, 2012]
- uniQure Extends Collaboration with Protein Sciences Corporation on Use of its expresSF+® Cell Line for Gene Therapy - June 19th, 2012 [June 19th, 2012]
- Anti-cocaine vaccine described in Human Gene Therapy Journal - June 19th, 2012 [June 19th, 2012]
- bluebird bio Receives U.S. and European Orphan Drug Designation for Novel Gene Therapy to Treat Adrenoleukodystrophy - June 19th, 2012 [June 19th, 2012]
- Close to a cure: Greater Hartford takes on rare Jewish genetic disease - June 19th, 2012 [June 19th, 2012]
- Gene Therapy Helps Treat Children with Rare Brain Disorder - June 20th, 2012 [June 20th, 2012]
- Gold nanoparticles capable of 'unzipping' DNA - June 21st, 2012 [June 21st, 2012]
- ‘Gene-silencing’ drug can halt and reverse deadly brain disorder - June 21st, 2012 [June 21st, 2012]
- uniQure Collaborates with UCSF on GDNF Gene Therapy in Parkinson's Disease - June 22nd, 2012 [June 22nd, 2012]
- Gene-silencing method offers possible therapy for Huntington's disease - June 22nd, 2012 [June 22nd, 2012]
- Gene mutations cause massive brain asymmetry - June 24th, 2012 [June 24th, 2012]
- Research and Markets: Translational Regenerative Medicine - Oncology, CNS and Cardiovascular-Rich Pipeline Features ... - June 25th, 2012 [June 25th, 2012]
- Stress Blocks Gene That Guards Brain Against Depression - June 26th, 2012 [June 26th, 2012]
- Targeted gene therapy enhances treatment for Pompe disease - June 26th, 2012 [June 26th, 2012]