A Little Bit of That from One of Your Grandparents: Interpreting Others’ Direct-to-Consumer Genetic Ancestry Results

Abstract

With more than 25 million tests sold by early 2019, direct-to-consumer genetic ancestry tests expose the public to critical issues of genetics, ancestry, and identity. This study examines how individuals understand the results of a genetic ancestry test. Twenty undergraduate students viewed and interpreted an unfamiliar individual’s ancestry results. In in-depth interviews, students indicated that the results were easy to read and understand, but that they had difficulty articulating the meaning of the ancestry groups presented in the results. Participants could not accurately paraphrase the test’s scientific explanation. Those who engaged with the scientific explanation developed doubts about the test’s credibility. There was little consensus about the legitimacy of identity claims from low-proportion ancestry groups. Some students reserved judgment while others identified specific thresholds for what ancestry proportions legitimize identity claims. Results contribute to the literature on the public’s understanding of ancestry, genetics, and data interpretation.