While I tend to agree that what we do with DNA and other sciences, I don't think that "...theres no way this technology wont be abused." is a good argument - it's exactly what the Left tells us when they say they need to control our guns and other parts of our lives.
This kind of tech could ultimately be used in nanobots, bots that could be injected as some sort of marker and control mechanism within the human body. Something that could essentially infect your entire system, hijack and take over your body systems and modify their function to achieve other purposes.
If you can inject a bot with artificial DNA that’s both scannable and able to receive radio signals within the human body, you got something that could be used for some very ugly purposes. Particularly if you can use it to make that bot replicate.
You get out of line, the bot gets a signal and starts doing very nasty things to you. That assume it won’t control you to the point where you even have a choice in the matter. We are talking Borg like tech here.