Zhang, Bing

Context.— Clinical laboratories are increasingly implementing pharmacogenomic (PGx) testing. Although PGx is similar to genetic testing for other indications, there are unique aspects that laboratories should consider. Objective.— To aid clinical laboratories that are implementing clinical PGx testing by describing characteristics of PGx test design and validation, as well as approaches to reporting. Resources that are useful for clinical laboratories performing PGx testing will be highlighted. Design.— The College of American Pathologists formed a workgroup composed of laboratorians with expertise in clinical PGx testing. The workgroup included representatives from the Association for Molecular Pathology and the American College of Medical Genetics and Genomics. The workgroup reviewed pertinent literature, as well as experience from proficiency testing and from members’ laboratories. Results.— The workgroup recommends that laboratories implementing PGx consider the following concepts: testing platform, test design (ie, selection of pharmacogenes and variants/alleles), use of reference materials during test development and as controls during clinical runs, star allele and standard nomenclature systems, translations from genotype to predicted phenotype, and considerations for result reporting including making medication recommendations. The workgroup provides considerations when using report vendors, emphasizing the clinical laboratory’s role and responsibility when implementing such reporting tools from vendors. Conclusions.— Clinical laboratories should be familiar with the fundamentals of PGx, ensure that PGx testing meets the applicable regulatory requirements for all aspects of the clinical laboratory testing process, and follow recommendations for standardization of nomenclature and reporting.

Context.— Next-generation sequencing (NGS)–based assays are used for diagnosis of diverse inherited disorders. Limited data are available pertaining to interlaboratory analytical performance of these assays. Objective.— To report on the College of American Pathologists (CAP) NGS Germline Program, which is methods based, and explore the evolution in laboratory testing practices. Design.— Results from the NGS Germline Program from 2016–2020 were analyzed for interlaboratory analytical performance. Self-reported laboratory testing practices were also evaluated. Results.— From 2016–2020, a total of 297 laboratories participated in at least 1 program mailing. Of the 289 laboratories that provided information on tests offered, 138 (47.8%) offered only panel testing throughout their enrollment, while 35 (12.1%) offered panels and exome testing, 30 (10.4%) offered only exomes, 9 (3.1%) offered only genomes, and 15 (5.2%) offered panels, exomes, and genomes. The remainder (62 laboratories, 21.4%) changed their test offerings during the 2016–2020 timeframe. Considering each genomic position/interval, the median detection percentage at variant positions across the 2016–2020 mailings ranged from 94.3% to 100%, while at reference positions (no variant detected), the median correct response percentage was 100% across all mailings. When considering performance of individual laboratories, 89.5% (136 of 152) to 98.0% (149 of 152) of laboratories successfully met the detection threshold (≥90% of the variants present), while 94.6% (87 of 92) to 100% (163 of 163) of laboratories met the 95% specificity threshold across mailings. Conclusions.— Since the inception of this program, laboratories have consistently performed well. The median sensitivity and specificity of detection of sequence variants included in this program (eg, single nucleotide variants, insertions, and deletions) were 100.0%.

Context Gene editing–based therapies are currently in development in the areas of oncology, inherited disease, and infectious disease. These potentially life-altering therapies are derived from decades of research in both academic and industry settings that developed technologies rooted in principles and products of nature. However, with such technologic developments come many important considerations, including adverse risks, high cost, and ethical questions. Objective To educate pathologists about gene editing technologies, inform them of potential indications and risks, outline regulatory and practical issues that could affect hospital-based practice and laboratory testing, and advocate that pathologists need to be present at discussions among industry and regulators pertaining to gene editing–based therapies. Design A Gene Editing Workgroup, facilitated by the College of American Pathologists Personalized Health Care Committee and consisting of pathologists of various backgrounds, was convened to develop an educational paper to serve as a stimulus to increase pathologist involvement and inquiry in gene editing therapeutic and diagnostic implementation. Results Through multiple discussions and literature review, the workgroup identified potential gaps in pathologists' knowledge of gene editing. Additional topics that could impact pathology and laboratory medicine were also identified and summarized in order to facilitate pathologists as stakeholders in gene editing therapy administration and monitoring and potential use in diagnostics. Conclusions Gene editing therapy is a complex but potentially transformative area of medicine. This article serves as an introduction to pathologists to assist them in future discussions with colleagues and potentially identify and alter pathology practices that relate to gene editing.