I found this topic so interesting that I immediately conducted a quick search online on the subject. I found the article that I think you may be referring to, and I have to say, it's pretty mind-blowing to think that those Pacific Islanders seem to be carrying that unknown DNA. I definitely want to learn more about this.
I haven't heard about this, but it seems kind of hard to believe. It makes me think that someone is trying to get people stirred up so they may be more likely to believe that aliens do exist and have actually been here on Earth at some point in time.