Theoretically, yes, it’s certainly possible. I must say, I haven’t heard of such a project, however it would by no means surprise me if at least governments had this in the works. As you could imagine, it would certainly be useful.
The mechanism by which this could occur are numerous, stating the use of DNA, as you have, is merely the tip of the iceberg. The RNA, introns and Ribosomal, aswell as mitochondrial, DNA fragments that could also be targeted make this a true possibility.
Though, as I have stated, I know of no such current projects. Most appear to be based on saving mankind, rather than destroying it :-P