This is nonsense. You replace a H on DNA with an OH, you don't change the charge. Either the seminar-giver, or the reporter, doesn't know what he's talking about. I strongly suspect it's the latter.
I did a search at the JPL website for a seminar held on Novmber 5 2004 that fits this description. I couldn't find one. Perhaps someone else might have better luck?
Me either. Must be my close-mindedness. Better than being so "open-minded" as to accept something merely because it reinforces one's previous beliefs, I suppose....