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INTRODUCTION: The rapidly expanding direct-to-consumer genetic testing (DTC GT) market is one area where narratives of underrepresented populations have not been explored extensively. This study describes African-American consumers' personal experiences with and perceptions about DTC GT and explores similarities and differences between African-Americans and an earlier cohort of mostly European American consumers. METHODS: Twenty semi-structured, qualitative interviews were held with individuals who self-identified as Black/African-American and completed DTC GT between February 2017 and February 2020. Interviews were transcribed and consensus-coded, using inductive content analysis. RESULTS: Participants generally had positive regard for DTC GT. When considering secondary uses of their results or samples, most participants were aware this was a possibility but had little concrete knowledge about company practices. When prompted about potential uses, participants were generally comfortable with research uses but had mixed outlooks on other nonresearch uses such as law enforcement, cloning, and product development. Most participants expressed that consent should be required for any secondary use, with the option to opt out. The most common suggestion for companies was to improve transparency. Compared to European American participants, African-American participants expressed more trust in DTC GT companies compared to healthcare providers, more concerns about law enforcement uses of data, and a stronger expression of community considerations. DISCUSSION/CONCLUSION: This study found that African-American consumers of DTC GT had a positive outlook about genetic testing and were open to research and some nonresearch uses, provided that they were able to give informed consent. Participants in this study had little knowledge of company practices regarding secondary uses. Compared to an earlier cohort of European American participants, African-American participants expressed more concerns about medical and law enforcement communities' use of data and more reference to community engagement.
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Lifelong noninvasive rejection monitoring in heart transplant patients is a critical clinical need historically poorly met in adults and unavailable for children and infants. Cell-free DNA (cfDNA) donor-specific fraction (DF), a direct marker of selective donor organ injury, is a promising analytical target. Methodological differences in sample processing and DF determination profoundly affect quality and sensitivity of cfDNA analyses, requiring specialized optimization for low cfDNA levels typical of transplant patients. Using next-generation sequencing, we previously correlated elevated DF with acute cellular and antibody-mediated rejection (ACR and AMR) in pediatric and adult heart transplant patients. However, next-generation sequencing is limited by cost, TAT, and sensitivity, leading us to clinically validate a rapid, highly sensitive, quantitative genotyping test, myTAIHEART®, addressing these limitations. To assure pre-analytical quality and consider interrelated cfDNA measures, plasma preparation was optimized and total cfDNA (TCF) concentration, DNA fragmentation, and DF quantification were validated in parallel for integration into myTAIHEART reporting. Analytical validations employed individual and reconstructed mixtures of human blood-derived genomic DNA (gDNA), cfDNA, and gDNA sheared to apoptotic length. Precision, linearity, and limits of blank/detection/quantification were established for TCF concentration, DNA fragmentation ratio, and DF determinations. For DF, multiplexed high-fidelity amplification followed by quantitative genotyping of 94 SNP targets was applied to 1168 samples to evaluate donor options in staged simulations, demonstrating DF call equivalency with/without donor genotype. Clinical validation studies using 158 matched endomyocardial biopsy-plasma pairs from 76 pediatric and adult heart transplant recipients selected a DF cutoff (0.32%) producing 100% NPV for ≥2R ACR. This supports the assay's conservative intended use of stratifying low versus increased probability of ≥2R ACR. myTAIHEART is clinically validated for heart transplant recipients ≥2 months old and ≥8 days post-transplant, expanding opportunity for noninvasive transplant rejection assessment to infants and children and to all recipients >1 week post-transplant.