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Updated: May 16, 2026
05:53
Candidate Gene Testing in Clinical Cohort Studies with Multiplexed Genotyping and Mass Spectrometry
Published on: June 21, 2018
Mapping the incidentalome: estimating incidental findings generated through clinical pharmacogenomics testing
Matthew J Westbrook1, M Frances Wright, Sara L Van Driest
1Center for Biomedical Ethics and Society, Vanderbilt University, Nashville, Tennessee, USA.
Summary
Multiplex genetic testing for pharmacogenomics can yield numerous incidental findings, with significant variations across ancestry groups. Developing clear clinical policies is crucial for managing these unexpected genetic results.
Area of Science:
- Genetics
- Pharmacogenomics
- Clinical Diagnostics
Background:
- Multiplex genetic technologies are increasingly used in clinical settings, particularly for pharmacogenomics.
- Data on incidental findings from these tests are essential for policy development.
- Understanding disparities in incidental findings across ancestry groups is critical.
Purpose of the Study:
- To quantify and characterize incidental, non-pharmacogenomic genotype-phenotype associations from clinical genotyping.
- To assess the potential impact of incidental findings in pharmacogenomic testing.
- To identify disparities in incidental findings relevant to different ancestry groups.
Main Methods:
- Utilized the Pharmacogenomic Resource for Enhanced Decisions in Care and Treatment (PREDICT) program.
- Prospective clinical genotyping of 34 pharmacogenomic-related genes.
- Curated 5,566 journal articles to identify genotype-phenotype associations.
Main Results:
- Identified 372 potential incidental genotype-phenotype associations.
- 287 associations were supported by studies with odds ratios ≥2.0 or ≤0.5.
- Significant variation in potentially relevant findings was observed across ancestry groups.
Conclusions:
- The high number of potential incidental findings necessitates rigorous clinical policies.
- Effective management strategies are needed for healthcare institutions, providers, and patients.
- Addressing disparities in incidental findings is important for equitable care.
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