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Updated: Jun 27, 2026
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Candidate Gene Testing in Clinical Cohort Studies with Multiplexed Genotyping and Mass Spectrometry
Published on: June 21, 2018
Race does not explain genetic heterogeneity in pharmacogenomic pathways
Jane L Yen-Revollo1, J Todd Auman, Howard L McLeod
1UNC Institute for Pharmacogenomics and Individualized Therapy, University of North Carolina, Chapel Hill, Campus Box 7360, 3203 Kerr Hall, Chapel Hill, NC 27599-7360, USA.
Pharmacogenomics
|November 21, 2008
Summary
Race is not a reliable predictor of genetic variations influencing drug response. Individual genetic differences, not racial groupings, are more significant for personalized medicine. This study highlights limitations in using race as a surrogate for genotyping.
Area of Science:
- Pharmacogenomics
- Human Genetics
- Population Genetics
Background:
- Polymorphic alleles significantly impact drug responses.
- Pre-treatment patient genotyping is currently impractical.
- Racial disparities in polymorphism frequencies necessitate alternative predictive methods.
Purpose of the Study:
- To determine if patient race can serve as a surrogate for genetic genotyping.
- To assess the predictive value of race for drug-relevant genetic variants.
- To evaluate the feasibility of race-based personalized medicine.
Main Methods:
- Hierarchical clustering and principal components analysis were applied.
- Tag single nucleotide polymorphisms (SNPs) from three key pathways (irinotecan, 5-fluorouracil, insulin) were analyzed.
- Data from 270 individuals across four racial groups from the International HapMap Project were used.
Main Results:
- Individuals from different races were dispersed across irinotecan and 5-fluorouracil pathways.
- Principal components analysis indicated race was not a primary factor in SNP data variance.
- Clustering by race was more pronounced for endogenous insulin signaling pathway SNPs.
Conclusions:
- Individual genetic variation, not racial grouping, predominantly determines drug response.
- Race is inadequate as a surrogate for individualized pharmacogenetic therapy.
- Personalized medicine requires individual genotyping over race-based predictions.
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