Mya Symons
Mya Symons
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- 1,029
- Location
- Washington
I was not sure where to post this. I was looking at the medical and science journal abstracts and I noticed that one of the doctors often mentioned had the same last name as me. This is unusual because my last name is not common. We are probably related in some way. Anyway, he was kind enough to e-mail me back very detailed answers to my questions. He has a Ph. D. in Biochemistry and Biophysics and has worked with retroviruses for many years. I believe he also worked on the human genome project and served as an editor to one of the virology journals.
One thing I am confused about: Did the NIH and FDA study prove that there are several variations of MuLv related viruses, even within the same person? I thought it did. I think he is saying he believes there are not many variations. --he says they "have not evolved"
Here is the e-mail
Hello. My name is Rebecca _____________. I hail from the MN __________ clan. I came across your name while attempting to read some medical journal reports on retroviruses. My husband, my son, and I have been sick for several years with CFS/ME (Chronic Fatigue Syndrome/Myalgic Encephalitis) and/or fibromyalgia. I see your interest is retroviruses. I was wondering if you have been following the research on XMRV. Have you read the recently released NIH and FDA study? Do you think that XMRV or MuLv related retroviruses could possibly be the cause of the illness associated with some cases of Chronic Fatigue Syndrome and Fibromyalgia or could be one of the causes? Do you believe that it is possible for a mouse retrovirus to be passed to humans or is this too far of a jump?
Dear Rebecca,
While it is very much of a pleasant surprise to get an email from another ____________ it is painful to know the circumstances. I can only imagine how frustrating such an illness is.
I have been in the retrovirus field for 35 years, although most of our work is with HIV. We do have a small epidemiology study with XMRV we are trying to do. My guess is it will be negative as we will be looking at blood plasma samples (aka samples of convenience). I know most of the people in this new field, especially the ones who themselves have been in the retrovirus field for awhile.
Your questions are right on mark. I haven’t read the papers carefully yet but I have seen the data from a number of studies at recent meetings. Given the medical importance there has been a lot of work in a relatively short period of time. To be honest, I have never seen a field reach such a level of confusion so quickly. Remember, this field started as being involved with prostate cancer. Given the claims going around I am impressed with your willingness to be cautious in what you believe.
The X in XMRV stands for xenotropic. This is an odd set of retroviruses that have been found in the mouse genome. At some point these viruses infected mice (and being retroviruses some of them wound up as part of the mouse genome). Along the way certain mice developed mutations in the receptor for the virus and at that point the virus could no longer infect these mice even though the viral genome was still part of the mouse genome. These viruses, when induced from mouse cells, can infect cells of other species, thus the name xenotropic. Yes, they can infect human cells. Can they infect humans? I don’t know, there is way more biology in infecting an entire organism and persisting in a population.
There are good reasons to worry about XMRV being a false positive result. Many labs grow mouse cells and human cells in the same incubator and by chance there may have been contamination (a pipet used to take the tissue culture medium off of the mouse cells that was accidently used to put medium on the human cells would be enough to transfer the virus from the culture of mouse cells to the culture of human cells). Thus the detection of such mouse viruses in human cells in culture is suspect. Similarly, a favorite experiment is to put human tumors in mice and watch them grow (or try to cure them). These human cells would certainly get infected with the mouse xenotropic virus while in the mouse and this could wind up back in the lab incubator. Finally, the technique of polymerase chain reaction where we make many copies of DNA from a small number of copies so that we can detect it is famous for finding contaminants. There are plenty of reasons to be skeptical from the technique side. Conversely, when someone fails to find something is this just bad technique in another form? I tend to believe negative results from good labs, but it is hard to explain the positive results as all being lab contamination.
There is a meeting that is just being held on XMRV. I didn’t attend but I did get an email about a session summarizing the results from the meeting that will be put on the internet in real time and also archived. Based on your email I would guess that you will understand most of what is said so I encourage you to watch it. I am getting my lab together to watch it as I believe it will be the latest summary possible. Also, I know some of the panel members and they will give a thoughtful and fair interpretation.
I hope this is helpful. If you have more questions I would be glad to discuss them with you. I know lots about retroviruses. I am sorry but I don’t know much about CFS, but I guess I have lots of company there. If CFS is caused by a retrovirus then one class of the HIV drugs (called nucleoside analogs/chain terminators/NRTIs) should inhibit their replication. I suspect these are already being tested off label in CFS patients to see if there is any relief. If the results are positive it will be big news. If the results are negative we may not hear about it for awhile.
Best wishes,
Webcast Invitation
Wednesday 8 September
5.15 PM EDT / 11.15 AM CET
1st International Workshop on XMRV
Pathogenesis, Clinical and Public Health Implications
7 - 8 September 2010, Bethesda, MD, USA
Dear Colleagues,
In less than a week the International Workshop on XMRV will take place in Bethesda, MD, USA. We are happy to invite those people who are not able to attend the workshop to tune in to a webcast Q & A session on Wednesday 8 September, 5.15 PM EDT / 11.15 AM CET. Please use the following link to get connected: XMRV Webcast <http://www.newsletter-ve.com/mail/link.php?M=26742&N=226&L=137&F=H> . For those who cannot watch the webcast live, an archive version will be available for viewing at this same website by week’s end.
This webcast Q&A wrap-up session will touch on the latest developments in the field in order to evaluate the state of our knowledge, address controversies, and develop an understanding between experts that will help direct future research.
The Q & A panel will consist of the following experts in the field of XMRV:
Don Blair, National Cancer Institute, Bethesda, USA
John Coffin, Tufts University, Boston, USA
Jerry Holmberg, US Dept. of Health and Human Services, Washington,USA
Judy Mikovits, Whittemore Peterson Institute, Reno, USA The session will be chaired by:
Jonathan Stoye, National Institute for Medical Research, London, UK
Dear Rebecca,
Yes, you are welcome to post the response.
One of the things that I hope will happen soon is that a set of control samples get sent around to a number of labs. In this scenario someone creates a set of samples that are positive for XMRV and also some that are negative. These are coded then sent out and people are asked to test them and see if they can identify them correctly, the equivalent of a blinded taste test. This is going to be essential to start untangling the current state of confusion.
There are two more things that are perplexing. In studying HIV we have come to learn how rapidly a virus can evolve. The genome sequences from XMRV are surprisingly close to several distinct groups mouse viruses (called xenotropic and polytropic, the latter infects cells from many species including mice, unlike the xenotropic ones). This suggests they are not growing very much otherwise they would evolve between one person and the next. However, we have to admit we don’t know much about the evolution rates of these viruses even in mice, in contrast to all we’ve learned about HIV evolution. The other thing is that in mice these types of viruses are famous for causing tumors. As retroviruses, the viral genome is copied into DNA and inserted into the host cell DNA. This is a semi-random process. If the insertion happens by chance to be next to a host gene that controls cell growth then the inserted viral DNA can turn on that gene and cause the cell to start growing inappropriately. In fact, in the past we have used the position of the viral genome in the tumor cell DNA of experimentally infected mice to identify host genes involved in cancer (proto-oncogenes/i.e. normal genes that can be involved in cancer when inappropriately expressed or mutated). When the XMRV story started with prostate cancer everyone wanted to know “What are the host genes near the viral integration sites?” That is still an open question. However, we don’t know how XMRV could give rise to a CFS-type disease given what we know about what these viruses do in mice.
Take care,
One thing I am confused about: Did the NIH and FDA study prove that there are several variations of MuLv related viruses, even within the same person? I thought it did. I think he is saying he believes there are not many variations. --he says they "have not evolved"
Here is the e-mail
Hello. My name is Rebecca _____________. I hail from the MN __________ clan. I came across your name while attempting to read some medical journal reports on retroviruses. My husband, my son, and I have been sick for several years with CFS/ME (Chronic Fatigue Syndrome/Myalgic Encephalitis) and/or fibromyalgia. I see your interest is retroviruses. I was wondering if you have been following the research on XMRV. Have you read the recently released NIH and FDA study? Do you think that XMRV or MuLv related retroviruses could possibly be the cause of the illness associated with some cases of Chronic Fatigue Syndrome and Fibromyalgia or could be one of the causes? Do you believe that it is possible for a mouse retrovirus to be passed to humans or is this too far of a jump?
Dear Rebecca,
While it is very much of a pleasant surprise to get an email from another ____________ it is painful to know the circumstances. I can only imagine how frustrating such an illness is.
I have been in the retrovirus field for 35 years, although most of our work is with HIV. We do have a small epidemiology study with XMRV we are trying to do. My guess is it will be negative as we will be looking at blood plasma samples (aka samples of convenience). I know most of the people in this new field, especially the ones who themselves have been in the retrovirus field for awhile.
Your questions are right on mark. I haven’t read the papers carefully yet but I have seen the data from a number of studies at recent meetings. Given the medical importance there has been a lot of work in a relatively short period of time. To be honest, I have never seen a field reach such a level of confusion so quickly. Remember, this field started as being involved with prostate cancer. Given the claims going around I am impressed with your willingness to be cautious in what you believe.
The X in XMRV stands for xenotropic. This is an odd set of retroviruses that have been found in the mouse genome. At some point these viruses infected mice (and being retroviruses some of them wound up as part of the mouse genome). Along the way certain mice developed mutations in the receptor for the virus and at that point the virus could no longer infect these mice even though the viral genome was still part of the mouse genome. These viruses, when induced from mouse cells, can infect cells of other species, thus the name xenotropic. Yes, they can infect human cells. Can they infect humans? I don’t know, there is way more biology in infecting an entire organism and persisting in a population.
There are good reasons to worry about XMRV being a false positive result. Many labs grow mouse cells and human cells in the same incubator and by chance there may have been contamination (a pipet used to take the tissue culture medium off of the mouse cells that was accidently used to put medium on the human cells would be enough to transfer the virus from the culture of mouse cells to the culture of human cells). Thus the detection of such mouse viruses in human cells in culture is suspect. Similarly, a favorite experiment is to put human tumors in mice and watch them grow (or try to cure them). These human cells would certainly get infected with the mouse xenotropic virus while in the mouse and this could wind up back in the lab incubator. Finally, the technique of polymerase chain reaction where we make many copies of DNA from a small number of copies so that we can detect it is famous for finding contaminants. There are plenty of reasons to be skeptical from the technique side. Conversely, when someone fails to find something is this just bad technique in another form? I tend to believe negative results from good labs, but it is hard to explain the positive results as all being lab contamination.
There is a meeting that is just being held on XMRV. I didn’t attend but I did get an email about a session summarizing the results from the meeting that will be put on the internet in real time and also archived. Based on your email I would guess that you will understand most of what is said so I encourage you to watch it. I am getting my lab together to watch it as I believe it will be the latest summary possible. Also, I know some of the panel members and they will give a thoughtful and fair interpretation.
I hope this is helpful. If you have more questions I would be glad to discuss them with you. I know lots about retroviruses. I am sorry but I don’t know much about CFS, but I guess I have lots of company there. If CFS is caused by a retrovirus then one class of the HIV drugs (called nucleoside analogs/chain terminators/NRTIs) should inhibit their replication. I suspect these are already being tested off label in CFS patients to see if there is any relief. If the results are positive it will be big news. If the results are negative we may not hear about it for awhile.
Best wishes,
Webcast Invitation
Wednesday 8 September
5.15 PM EDT / 11.15 AM CET
1st International Workshop on XMRV
Pathogenesis, Clinical and Public Health Implications
7 - 8 September 2010, Bethesda, MD, USA
Dear Colleagues,
In less than a week the International Workshop on XMRV will take place in Bethesda, MD, USA. We are happy to invite those people who are not able to attend the workshop to tune in to a webcast Q & A session on Wednesday 8 September, 5.15 PM EDT / 11.15 AM CET. Please use the following link to get connected: XMRV Webcast <http://www.newsletter-ve.com/mail/link.php?M=26742&N=226&L=137&F=H> . For those who cannot watch the webcast live, an archive version will be available for viewing at this same website by week’s end.
This webcast Q&A wrap-up session will touch on the latest developments in the field in order to evaluate the state of our knowledge, address controversies, and develop an understanding between experts that will help direct future research.
The Q & A panel will consist of the following experts in the field of XMRV:
Don Blair, National Cancer Institute, Bethesda, USA
John Coffin, Tufts University, Boston, USA
Jerry Holmberg, US Dept. of Health and Human Services, Washington,USA
Judy Mikovits, Whittemore Peterson Institute, Reno, USA The session will be chaired by:
Jonathan Stoye, National Institute for Medical Research, London, UK
Dear Rebecca,
Yes, you are welcome to post the response.
One of the things that I hope will happen soon is that a set of control samples get sent around to a number of labs. In this scenario someone creates a set of samples that are positive for XMRV and also some that are negative. These are coded then sent out and people are asked to test them and see if they can identify them correctly, the equivalent of a blinded taste test. This is going to be essential to start untangling the current state of confusion.
There are two more things that are perplexing. In studying HIV we have come to learn how rapidly a virus can evolve. The genome sequences from XMRV are surprisingly close to several distinct groups mouse viruses (called xenotropic and polytropic, the latter infects cells from many species including mice, unlike the xenotropic ones). This suggests they are not growing very much otherwise they would evolve between one person and the next. However, we have to admit we don’t know much about the evolution rates of these viruses even in mice, in contrast to all we’ve learned about HIV evolution. The other thing is that in mice these types of viruses are famous for causing tumors. As retroviruses, the viral genome is copied into DNA and inserted into the host cell DNA. This is a semi-random process. If the insertion happens by chance to be next to a host gene that controls cell growth then the inserted viral DNA can turn on that gene and cause the cell to start growing inappropriately. In fact, in the past we have used the position of the viral genome in the tumor cell DNA of experimentally infected mice to identify host genes involved in cancer (proto-oncogenes/i.e. normal genes that can be involved in cancer when inappropriately expressed or mutated). When the XMRV story started with prostate cancer everyone wanted to know “What are the host genes near the viral integration sites?” That is still an open question. However, we don’t know how XMRV could give rise to a CFS-type disease given what we know about what these viruses do in mice.
Take care,