ERV FAQ: What's all this about the "Phoenix Virus"? Sounds like a Michael Crichton science fiction story!

This experiment proves that ERVs originated as retroviruses. 

 It is a good example of scientific prediction - if our ideas are correct, then we will observe so-and-so.  We did.

https://barryhisblog.blogspot.com/p/whats-all-this-about-phoenix-virus.html

A bunch of mad scientists looked at a set of very similar endogenous retroviruses (ERVs) that lurk in our genomes, and figured that maybe, they all derived from the same retrovirus, a retrovirus that either endogenized (entered the germ-line) independently on separate occasions, or endogenized once and repeatedly integrated in different locations via transposition. Because they thought that each ERV might derive from the same original retrovirus, but was wonky because reverse transcription is so error-prone, they figured that the ERVs were likely to have different incapacitating mutations. All they had to do, they thought, was to look at the genomes of all the ERVs and take a "majority vote" as to what the correct base was at each genetic position, and they might be able to reconstruct the genome of the original retrovirus. 

The reckless fools.

This page explains the experiment in more detail and links to their peer-reviewed report. https://barryhisblog.blogspot.com/p/the-phoenix-virus-explanation-of.html

This not science fiction.

See also, https://journals.asm.org/doi/10.1128/jvi.64.5.2245-2249.1990

There is more.

From Jon Peters’ Truthful Origins https://www.truthfulorigins.info/post/the-best-evidence-for-human-evolution-shared-ervs-evolution-part-2

Interestingly, a PhD student also resurrected a functional retrovirus [Derivation of HERV-KCON] from a family of ERVs, and published his dissertation in 2010. "Here, a HERV-K provirus whose sequence resembles that of an ancestral human-specific HERV-K(HML-2) was constructed. All viral proteins encoded by this provirus were demonstrated to be capable of functioning in the context of a retroviral replication cycle. While some recent studies have reconstituted “live” viruses from synthetic DNA (Cello et al., 2002; Tumpey et al., 2005), this and a similar study of HERV-K published nearly simultaneously (Dewannieux et al., 2006) are the first examples in which the replication cycle of a virus has been reconstituted using a group of sequences that represent ancient fossils and are demonstrably defective." 

https://digitalcommons.rockefeller.edu/cgi/viewcontent.cgi?referer=&httpsredir=1&article=1077&context=student_theses_and_dissertations

A mouse ERV reverted to a fully functional retrovirus provirus able to produce retroviruses with only 1 mutation. The defect in Emv-3 is caused by a single base substitution in codon 3 of p15gag.

https://pmc.ncbi.nlm.nih.gov/articles/PMC249385/pdf/jvirol00060-0381.pdf

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