Warranted confusion

see Consumers report lower confidence in their genetics knowledge following direct-to-consumer personal genomic testing

Many consumers realize they don’t really understand genetics after receiving direct-to-consumer test results from companies, according to a study of 23andMe and Pathway Genomics customers. Faced with detailed reports that highlight the complexity of interpreting genomic test results, consumers became less confident in their own understanding of genetics. The study results, reported in this issue, highlight the gap between what even highly educated and informed consumers think they know about genetics versus its inherent complexities. The Impact of Personal Genomics study, conducted by the PGen Study Group based at the University of Michigan, surveyed 998 customers before they purchased kits from two companies selling direct-to-consumer genetic tests and then followed up six months later. The surveys revealed that people who purchase these tests tend to be wealthy, college-educated, and overwhelmingly of non-Hispanic white ethnicity. They scored highly on baseline genetic knowledge, with the exception of one true–false question, “Most genetic disorders are caused by only a single gene,” which most participants thought was true. The research team suggests that the follow-up survey revealed a reevaluation of self-knowledge and a consequent better understanding of both the customers’ own limitations and the inherent complexities of the genomic tests currently being offered to the public. Few participants (20) consulted with a health-care provider before ordering the test, but those who did reported a better understanding of results, suggesting that greater involvement by health-care providers in the testing process may help consumers’ confidence in interpreting results. —Karyn Hede, News Editor

Variant interpretations inconsistent among genetic testing laboratories

see The challenge of comprehensive and consistent sequence variant interpretation between clinical laboratories

A comparison among a small sample of variant interpretations conducted by a variety of testing laboratories reveals that inconsistencies among reported results are alarmingly common. The Collagen Diagnostic Laboratory (CDL) at the University of Washington, a university-based clinical and research laboratory specializing in heritable connective-tissue disorders, studied reported results of 38 cases in which they were called in to offer a second opinion. These cases involved situations in which variant results identified a gene among those studied in the CDL. Data came from five private commercial laboratories (20 cases) and six academic laboratories (12 cases); the remaining 6 cases were from unidentified laboratories. The research team found 27 discrepant results, one-third of which were attributed to lack of access to private CDL data. However, half of the discrepant results could be attributed to lack of reference to current understanding of the biology of the investigated gene, and 19% could be attributed to lack of reference to publicly available data. The investigators concluded that laboratories are not making use of readily available public information that could improve the quality and consistency of variant interpretation and point out that data sharing among laboratories could also help minimize discrepant variant interpretations. To minimize inconsistent results, variant interpreters at different clinical genetics laboratories should be using the same interpretative tools, data sources, and variant-classification guidelines. The ACMG’s recent promulgation of interpretive standards may help this situation. —Karyn Hede, News Editor