Finally getting round to adding some comments on some oldish threads...
I was excited by this report, and it does still seem exciting to me, a reputable lab finding XMRV...once again, it is not just the WPI who are finding XMRV.
There is something odd about the LTRs. In the CROI presentations on alleged origins of XMRV, studying the diagrams relating to 'PreXMRV1' and 'PreXMRV2', note that the sequence identity mentioned does not seem to include the LTRs, which are very different between XMRV and the relevant mouse sequences. The LTRs are more than junk, as mentioned - they seem to contain sequences which are crucial for binding sites that would activate autoimmune-like processes: there was a published paper recently on the binding sites opened up by proteins in XMRV's LTRs, which may be relevant, since we are now seeing these oddities elsewhere in relation to the LTRs.
I was even more excited about the lunulas though! No lunulas whatsoever here either (it's always nice to confirm you fit in!), just a couple of tiny ones on both thumbs; I checked with a healthy friend and his lunulas are big and unmistakeable white crescents. My nails are also very pink. From the range of people who have all reported missing lunulas on this thread, it sounds to me like just about the strongest 'straw poll' we've ever had! - this seems to be common across many 'subgroups' and a poll would be very interesting. I would buy the B12 deficiency theory - but the stress theory makes no sense to me. If 'chronic stress' includes not just trauma but also environmental stressors (the position we always seem to back up to whenever anybody mentions 'stress') then what does the word 'stress' really mean? It seems to amount to meaning no more than 'something or other', since it's hard to think of a factor we might be considering as a cause which would not come under the heading of such a definition of 'stress'.
B12 is much more interesting...one quick note on B12: there was an interesting German paper on Alzheimer's recently (sorry, I would struggle to track it down) which seems to be saying that the B vitamins (6/9/12) have a role in protecting the nervous system from metals: my understanding is that the B vitamins help to remove iron and aluminium from the nervous system, thus they have a kind of neuroprotective role - and in Alzheimer's the tangled amyloid protein buildup may be caused by metals that haven't been detoxed.
That's my theory re: B12 at the moment, anyway, that the involvement of B12 deficiency linked to various nervous system disorders is because they are neuroprotectors, and if deficient or overstressed for whatever reason, there will be consequences for the nervous system. I think there are various other such factors at play with all the subgroupings - eg APOBEC3 mutations could be one pathway to a certain subgroup of pathology - but that the B vitamin issue runs right the way across a whole load of neurological conditions and is maybe even a kind of prerequisite for neurological conditions (ie people with healthy B12 levels won't suffer these effects) - and I even suspect we can include things like some/all forms of depression in that as well.
