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The viral DNA is copied by semiconservative replication and its labelling kinetics broadly follow those of host DNA during viral latency. At the earliest time the newly labelled material is mainly hybrid: an old light strand has acquired a heavy complementary strand. Fully heavy duplexes accumulate later, after heavy strands themselves serve as templates. Conservative copying would instead produce a separate fully heavy population from the first copying round, while dispersive copying would produce progressively shifting intermediate densities rather than these three discrete classes.

For an ideal synchronous population starting entirely light, one complete round gives only hybrid duplexes; after $n\ge 1$ rounds the hybrid fraction is $2^{1-n}$ and the fully heavy fraction is $1-2^{1-n}$. The actual culture is asynchronous, so these integer-generation proportions cannot simply be imposed at $t/23$ hours. The similar viral and cellular bars support replication coordinated with cell proliferation rather than rapid autonomous amplification. They do not establish that every episome initiates exactly once in every individual biological cell, or prove an initiation time within S phase. Persistent light material also warns against treating the population as a perfectly uniform set of cycling biological cells. The strand-accounting principle is the one tested in ^[ref].

The evidence supports NVNA1 as a sequence-specific organizer of viral chromatin, with possible additional roles in nuclear retention and episome partitioning. Binding to the origin of replication and DNA bridging explain assembly at separated viral repeat arrays. Access to recognition sites in nucleosomes and weakening of histone–DNA association provide a plausible way to make an origin accessible to cellular replication machinery. The density-labelling result is consistent with a latent genome using a host-coordinated copying programme; it does not establish that NVNA1 is itself a DNA polymerase or DNA helicase.

Association with host chromosomal DNA could also retain episomes in the nucleus and help distribute them during biological cell division. Such tethering is a plausible maintenance function, but the experiments here do not directly visualize a physical bridge between an episome and a host chromosome. Binding at a vulnerable host repeat could instead be an incidental consequence of recognition specificity. The enrichment of host chromosome rearrangements supports a damage connection; it does not show that chromosome breakage is required for viral replication or that integration is part of the normal latent programme. chromatin opening and host-locus interference are mechanistic interpretations of the presented binding data, not proof of one obligatory replication pathway.