Matrix attachment regions as targets for retroviral integration.
Johnson CN, Levy LS.
BACKGROUND: The randomness of retroviral integration has been debated for many years. Recent evidence indicates that integration site selection is not random, and that it is influenced by both viral and cellular factors. To study the role of DNA structure in site selection, retroviral integration near matrix attachment regions (MARs) was analyzed for three different groups of retroviruses. The objective was to assess whether integration near MARs may be a factor for integration site selection. RESULTS: Results indicated that MLV, SL3-3 MuLV, HIV-1 and HTLV-1 integrate preferentially near MARs, specifically within 2-kilobases (kb). In addition, a preferential position and orientation relative to the adjacent MAR was observed for each virus. Further analysis of SL3-3 MuLV insertions in common integration sites (CISs) demonstrated a higher frequency of integration near MARs and an orientation preference that was not observed for integrations outside CISs. CONCLUSIONS: These findings contribute to a growing body of evidence indicating that retroviral integration is not random, that MARs influence integration site selection for some retroviruses, and that integration near MARs may have a role in the insertional activation of oncogenes by gammaretroviruses.
Virol J. 2005 Aug 19;2(1):68 [Epub ahead of print]
This is an active area of research. It is exciting and beyond the biological aspects has important implications for the future of medicine.
The original issue is whether ERVs indicate common ancestry. Integration "preferentially near" specific MARs should be easily differentiated from "exactly in the same spot".
Two separate infection events may be near (assuming you're not misusing the evidence on this, as you did last night), in this case within 2kbp, while an inherited infection from a common ancestor would be in exactly the same spot.
And then we add that there are multiple ERV "fossils", thousands of them apparently, and the result is that the only reasonable answer is a common ancestor is the cause, not duplicate infections that just happen to match.
And then add the other matching items in DNA, the broken vitamin "C" gene, the evidence of the chromosome centemere evidence where Chimp vs. Human DNA line up, etc. etc.
Add morphological evidence. Add outside evolution theory that's been demonstrated, and never falsified.
Bottom line, there was a common ancestor. The puzzle fits.
But keep it up tallhappy. I'm sure there are suckers willing to pay money for eager biologists with a legal mind that tell them what they want to hear.