44. Clinical utility of pharmacogenomics testing with an expanded panel

Background: Goals of pharmacogenomics (PGx) include maximizing drug efficacy while minimizing drug toxicity. Genotyping panels interrogate a limited number of single nucleotide polymorphisms (SNPs) at a locus to determine phenotype. Under the *-allele naming system, absence of variation at tested sites is designated the 'wild-type' allele. Consequently, variation at untested nucleotides that may alter phenotypes and PGx-based recommendations remain unknown. This study assessed the frequency of clinically significant variation that would have been missed if testing commonly recommended alleles versus an expanded panel available in our health system.