Scientific Director Suzanne Vernon, PhD
We are not alone …
By Suzanne D. Vernon, PhD
We are not alone.
By that I mean our human genome – the genetic code that determines traits such as height, hair and eye color – is not all that makes us who we are. As high-throughput sequencing technology has developed, we have learned that our genome is really a metagenome. Simply put, humans are made up of genomes from many individual organisms including parasites, bacteria and viruses. The human genome project completed sequencing the 20,000-25,000 human genes in 2003. Around 2005, the National Institutes of Health (NIH) launched the Human Microbiome project to catalogue all the bacteria in various parts of the human body. Yet to come is the Human Virome (all viruses) project, although there are already a few scientific groups around the world attempting to catalogue the viruses within us. You can see that our bodies are actually complex ecosystems influenced by physical and biological factors from inside and out. As with any ecosystem, a balance of these factors is required to maintain good health.
Many infectious agents have been implicated in CFS. Chronic diseases can stem from infectious agents and the microbes within. Human papillomaviruses are examples of infectious agents that cause cancer. The composition of bacteria in the gut determines healthy metabolism. Infectious agents likely determine more immune-mediated syndromes and chronic diseases including CFS than is currently appreciated by the scientific and medical communities.
Enter XMRV. In a review article titled, “The human retrovirus XMRV in prostate cancer and chronic fatigue syndrome,” published online June 1, 2010 in Nature Reviews Urology, Drs. Robert H. Silverman, Carvell Nguyen, Christopher J. Weight and Eric A. Klein describe the rapidly emerging science attempting to decipher the role of XMRV in human disease. The authors conclude that much remains to be done to understand the role of XMRV in CFS, but first and most importantly, independent confirmation and validation of the XMRV/CFS association must be made. If the association of XMRV with CFS is confirmed, what started as a controversial finding will turn CFS into an intense and fundable area of research – one with relevance to the many other immune-mediated syndromes that presently lack firm biologic explanations.
What does XMRV have to do with our metagenome? Most of us live with viruses (e.g., Epstein Barr virus (EBV)) that are a stable part of our metagenome. It is possible that XMRV is part of our metagenome; if so, it might explain why XMRV was detected in four percent of the healthy controls in the Science paper and individuals with other diagnoses in a recent study by Nicole Fisher, et al., published in Emerging Infectious Diseases. But most people with persistent viruses do not get sick, so what determines who gets CFS? Our immune system works to hold viruses like EBV at bay – this should be thought of as normal, healthy ecosystem. As indicated above, there are a number of things that can occur throughout our lifetime that challenge the ecosystem balance and have the potential to turn a benign virus into a virus that could cause chronic inflammation, autoimmune disease, cancer or CFS. Once we know if XMRV is confirmed, diagnostic, treatment and prevention studies for XMRV will begin. At the same time, studies on how XMRV – as well as other viruses and infectious agents implicated in CFS – alter the body’s ecosystem should be supported. While not easy to design and implement, these types of studies have the potential to define the CFS ecosystem and indicate therapeutic measures that could return the body’s ecosystem to a healthy state.
Silverman RH, Nguyen C, Weight CJ, Klein EA. The human retrovirus XMRV in prostate cancer and chronic fatigue syndrome. Nat Rev Urol. 2010 Jun 1.
Fischer N, Schulz C, Stieler K, Hohn O, Lange C, Drosten C, Aepfelbacher M. XMRV gammaretrovirus in respiratory tract. Emerging Infectious Diseases. 2010 Jun.
Suzanne D. Vernon, PhD, earned her doctorate in virology at the University of Wisconsin at Madison and worked in public health research on infectious diseases at the U.S. Centers for Disease Control and Prevention for 17 years before joining the CFIDS Association of America’s staff as scientific director in 2007. She has more than 70 peer-reviewed scientific publications on topics including human immunodeficiency virus, human papillomavirus, cervical cancer and chronic fatigue syndrome. Dr. Vernon has initiated and participated in numerous international and multidisciplinary research collaborations and she now leads the CFIDS Association’s research program. The CFIDS Association of America is the nation’s largest philanthropic supporters of CFS research.
Dr. Vernon will be giving two webinars in June 2010 on research topics. Learn more about them at http://www.cfids.org/cfidslink/2010/040703.asp.
Please participate in our June Risk Factors survey at https://www.surveymonkey.com/s/RiskFactors. This data will help quide several research projects under way.
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