Clinically actionable genotypes among 10,000 patients with preemptive pharmacogenomic testing.

Since September 2010, more than 10,000 patients have undergone preemptive, panel-based pharmacogenomic testing through the Vanderbilt Pharmacogenomic Resource for Enhanced Decisions in Care and Treatment program. Analysis of the genetic data from the first 9,589 individuals reveals that the frequency of genetic variants is concordant with published allele frequencies. Based on five currently implemented drug-gene interactions, the multiplexed test identified one or more actionable variants in 91% of the genotyped patients and in 96% of African American patients. Using medication exposure data from electronic medical records, we compared a theoretical "reactive," prescription-triggered, serial single-gene testing strategy with our preemptive, multiplexed genotyping approach. Reactive genotyping would have generated 14,656 genetic tests. These data highlight three advantages of preemptive genotyping: (i) the vast majority of patients carry at least one pharmacogenetic variant; (ii) data are available at the point of care; and (iii) there is a substantial reduction in testing burden compared with a reactive strategy.

Inclusion of pediatric samples in an opt-out biorepository linking DNA to de-identified medical records: pediatric BioVU.

The Vanderbilt DNA repository, BioVU, links DNA from leftover clinical blood samples to de-identified electronic medical records (EMRs). After initiating adult sample collection, pediatric extension required consideration of ethical concerns specific to pediatrics and implementation of specialized DNA extraction methods. In the first year of pediatric sample collection, more than 11,000 samples from individuals younger than 18 years were included. We compared data from the pediatric BioVU cohort with those from the overall Vanderbilt University Medical Center pediatric population and found similar demographic characteristics; however, the BioVU cohort had higher rates of select diseases, medication exposures, and laboratory testing, demonstrating enriched representation of severe or chronic disease. The fact that the sample accumulation is not balanced may accelerate research in some cohorts while limiting the study of relatively benign conditions and the accrual of unaffected and unbiased control samples. BioVU represents a feasible model for pediatric DNA biobanking but involves both ethical and practical considerations specific to the pediatric population.