Here is a nice open access review article on ERVs and their association with cancer:
While thats wonderfully interesting, what I want to focus on is a bit at the end. More information I have never heard before–
An amino acid sequence similar to HERV-K-MEL, recognized to cause a significant protective effect against melanoma, is shared by the antigenic determinants expressed by some vaccines such as BCG, vaccinia virus and the yellow fever virus.
A recent epidemiological study provided provisional evidence of how melanoma risk could possibly be reduced if the yellow fever virus vaccine (YFV) were received at least 10 years before, possibly preventing tumor initiation rather than culling melanoma cells already compromised.
Wait, WAT?? All those vaccines (bacterial and viral) are associated with lower melanoma rates? WAT??
HERV-K-MEL is a pseudogene inside of an ERV (junk within junk!). It has been shown to be expressed in melanomas and ‘sarcoma, lymphoma, bladder, breast and ovarian cancer’. By chance, it appears as if some of the proteins in TB, Small Pox, and Yellow Fever vaccines have a similar enough structure that our immune system can be trained to see ‘Yellow Fever’, but can also see HERV-K-MEL, a cancer marker, too!
This wasnt done on purpose at all!
And we didnt make the connection between vaccine, molecular mimicry, ERV expression, and cancer until 2005!
I think that is relatively fast to connect some WEIRD dots!
Its 2013 and I am just now learning about this, and still amazed, myself!
Edward Jenner, 1796, uses cowpox as a vaccine against small pox. 1939 we realize that our ‘cowpox’ vaccine evolved into something else, we name it ‘vaccinia’ and just roll with it. 2005 we notice it has a protective effect against some kinds of cancers (just kinda protective, we arent doing it on purpose, here! its a side-effect!), which have a messed up active ERV.