Adverse events in cancer genetic testing: the third case series.

After repeated media attention in 2013 due to the Angelina Jolie disclosure and the Supreme Court decision to ban gene patents, the demand for cancer genetic counseling and testing services has never been greater. Debate has arisen regarding who should provide such services and the quality of genetics services being offered. In this ongoing case series, we document 35 new cases from 7 states (California, Connecticut, Florida, Georgia, Missouri, Pennsylvania, and Utah) and the District of Columbia of adverse outcomes in cancer genetic testing when performed without the involvement of a certified genetic counselor. We identified 3 major themes of errors: wrong genetic tests ordered, genetic test results misinterpreted, and inadequate genetic counseling. Patient morbidity and mortality were an issue in several of these cases. The complexity of cancer genetic testing and counseling has grown exponentially with the advent of multigene panels that include rare genes and the potential for more variants of uncertain significance. We conclude that genetic counseling and testing should be offered by certified genetics providers to minimize the risks, maximize the benefits, and utilize health care dollars most efficiently.

Classification of missense substitutions in the BRCA genes: a database dedicated to Ex-UVs.

Unclassified sequence variants (UVs) arising from clinical mutation screening of cancer susceptibility genes present a frustrating issue to clinical genetics services and the patients that they serve. We created an open-access database holding missense substitutions from the breast and ovarian cancer susceptibility genes BRCA1 and BRCA2. The main inclusion criterion is that each variant should have been assessed in a published work that used the Bayesian integrated evaluation of unclassified BRCA gene variants. Transfer of data on these substitutions from the original publications to our database afforded an opportunity to analyze the missense substitutions under a single model and to remove inconsistencies that arose during the evolution of the integrated evaluation over the last decade. This analysis also afforded the opportunity to reclassify these missense substitutions according to the recently published IARC 5-Class system. From an initial set of 248 missense substitutions, 31 were set aside due to nonnegligible probability to interfere with splicing. Of the remaining substitutions, 28 fell into one of the two pathogenic classes (IARC Class 4 or 5), 174 fell into one of the two nonpathogenic classes (IARC Class 1 or 2), and 15 remain in IARC Class 3, "Uncertain." The database is available at http://brca.iarc.fr/LOVD.