Purpose-American adult adoptees may possess limited amounts of information about their biological families and turn to direct-to-consumer personal genomic testing (PGT) for genealogical and medical information. We investigated the motivations and outcomes of adoptees undergoing PGT using data from the Impact of Personal Genomics (PGen) Study. Methods-ThePGen Study surveyed new 23andMe and Pathway Genomics customers prior to and 6 months after receiving PGT results. Exploratory analyses compared adoptees' and nonadoptees' PGT attitudes, expectations, and experiences. We evaluated the association of adoption status with motivations for testing and post-disclosure actions using logistic regression models.Results-Of 1607 participants, 80 (5%) were adopted. As compared to non-adoptees, adoptees were more likely to cite limited family health history knowledge (OR = 10.1; 95% CI = 5.7-19.5) and the opportunity to learn genetic disease risks (OR = 2.7; 95% CI = 1.6-4.8) as strong motivations for PGT. Of 922 participants who completed 6-month follow-up, there was no Users may view, print, copy, and download text and data-mine the content in such documents, for the purposes of academic research, subject always to the full Conditions of use:http://www.nature.com/authors/editorial_policies/license.html#terms Figure S1 presents a flowchart of the PGen Study design and indicates the composition of the baseline and 6-month survey samples. Table S1 and Figure S2 compare the self-reported family health history information of adoptees and non-adoptees. Table S2 presents adoptees' and non-adoptees' views on genetic privacy 6 months following PGT. Table S3, Table S4, and Table S5 compare the demographics of the 6-month survey sample to those who were not retained for follow-up or excluded from the 6-month analyses for all participants, for adoptees, and for non-adoptees, respectively. Author Manuscript significant association between adoption status and PGT-motivated healthcare utilization or health behavior change. HHS Public AccessConclusion-PGT allows adoptees to gain otherwise inaccessible information about their genetic disease risks and ancestry, helping them to fill the void of an incomplete family health history.