Earlier quoted context omitted.
That's why I would like to send my DNA in anonymously; I don't want to link anything to my DNA data.
Even if you send it in anonymously, your DNA is so unique to you that by comparing it to other data you can infer at least the last name. See for example http://www.ncbi.nlm.nih.gov/pubmed/23329047
That's a valid concern, actually, my last name is fairly rare, especially in the United States.