[Diamond]

By all means cite evidence of expression of a heavily methylated retroviral insertion.

I don't know about your qualification of "heavily methylated", but generally regarding trancriptionally active ERV's and protein expression in humans, as well as possible functionality, and interestingly, even insertion bias - Perpetually mobile footprints of ancient infections in human genome - Eugene D. Sverdlov

Cordially,

[Right Wing Professor]

The paper referenced does not claim LTRs are expressed. But regardless of whether retrotransposons sometimes have a functional role in humans, the occurrence of homologous retrotransposons in orthologous locations is strong evidence of common descent.