From a DNA test for parents, in the absence of documents, I believe that it would be possible to list the natural parents and probably with the "confirmed by DNA" tag. My understanding is that WikiTree is preferentially for genetic connections. Hence, in my own mother's profile, I have added her biological parent in the family links, but reference her legal parents with the appropriate WikiTree tags in the Biography text. Not 100% sure if this is the preferred way...It is more challenging with her father's ancestry, as he was out-of-wedlock, and while I've identified a strong candidate for his father from DNA matches, in the absence of closer connections and any documentation, I'm not sure how to add him. The DNA evidence is strong, with about 20 connections at the appropriate match level with his legitimate, documented descendants, but it's not impossible that my actual great grandfather was a son, brother, or nephew. Similar issues with the parents of my mothers, maternal grandmother.