This is just pure assumption from my part, I know nothing about this. But extrapolating from your point: > It may be important for spacing out sections of DNA

This is just pure assumption from my part, I know nothing about this. But extrapolating from your point: > It may be important for spacing out sections of DNA Is it possible that there IS selection pressure for unread DNA? I could imagine that cells with comparatively huge chromosomes last a bit longer, since you'd hope that some percentage of those pairs are just cannon fodder for the usual mutagenic sources. (energy, viruses, being a European king, etc) Like you can either make the bullseye on the target smaller, or spread out the points across the whole face of the target. Again, no idea what I'm talking about, but maybe the researchers here are seeing a breakdown in the "control characters" around these parts? Maybe there's a sort of null start/null terminate at both ends in the "real" DNA, and when it breaks down, these unintended sacrificial spacers get parsed.