Pharmacogenomics has significantly added to our understanding of drug responses in clinical pharmacology, changing the paradigm of treatment decisions. Interrogations of both inherited and somatic variations for therapeutic purposes are increasingly being adopted in clinics, where quality control (QC) materials are required. However, for many pharmacogenomic tests, the acquisition of well-characterized QC materials is often difficult or impossible. In this review, several sources of appropriate QC materials for therapy-associated genetic testing are discussed. Among them, the novel methods for producing renewable controls that resemble patient samples are highlighted. Owing to technological complexity, more efforts are needed to develop proper controls for next-generation sequencing-based assay.