Abstract: At-home DNA testing has become increasingly popular due to the ability to be able to gain both ancestry and health information, as well as connect with others who share your DNA. Do users have reasonable mental models of how these systems work? Do users have privacy concerns and what do they understand as the benefits and risks involved? We conducted 27 interviews with Canadian users of at-home DNA testing companies. Our interviews covered perceived and desired data use, data management, data sharing practices, control over data, and any regrets. Our qualitative analysis revealed that many users have inconsistencies in their mental models and liken their DNA data to their data stored with existing technologies, such as social media, rather than health data. They are generally either dismissive of privacy concerns towards themselves or their relatives or they had not considered privacy in their choice. We discuss our findings and propose possible future work in this area.