Reporting Practices for Variants of Uncertain Significance from Next Generation Sequencing Technologies

The nature of next generation sequencing technologies (NGS) results in the generation of large amounts of data and the identification of numerous variants, for some of which the clinical significance may be difficult to ascertain based on our current knowledge. These Variants of Uncertain Significance (VUS) may be identified in genes in which the function is known or unknown and which may or may not be related to the original rationale for sequencing the patient. Little is known about whether laboratories report VUS to clinicians and current guidelines issued by some of the most notable professional bodies do not provide specific recommendations on this point. To address this, 26 interviews were conducted with 27 laboratory personnel, representing 24 laboratories in Europe (12), Canada (5) and Australasia (7) in order to explore their reporting practices. Participants highlighted that the classification of variants is a real challenge despite the presence of classification guidelines. We identified variation in the reporting practices of VUS across the laboratories within the study. While some laboratories limit their reporting to variants that are pathogenic and thought to be causative of the phenotype, more commonly laboratories report VUS when they are identified in genes related to the clinical question. Some laboratories will also report VUS in candidate genes. VUS that are secondary findings are generally not reported. While it is unclear whether uniformity in reporting is desirable, exploring the perspectives of laboratory personnel undertaking these analyses are critical to ensure the feasibility of any future reporting recommendations.