Personal genome testing: Test characteristics to clarify the discourse on ethical, legal and societal issues

Background: As genetics technology proceeds, practices of genetic testing have become more heterogeneous: many different types of tests are finding their way to the public in different settings and for a variety of purposes. This diversification is relevant to the discourse on ethical, legal and societal issues (ELSI) surrounding genetic testing, which must evolve to encompass these differences. One important development is the rise of personal genome testing on the basis of genetic profiling: the testing of multiple genetic variants simultaneously for the prediction of common multifactorial diseases. Currently, an increasing number of companies are offering personal genome tests directly to consumers and are spurring ELSI-discussions, which stand in need of clarification. This paper presents a systematic approach to the ELSI-evaluation of personal genome testing for multifactorial diseases along the lines of its test characteristics. Discussion: This paper addresses four test characteristics of personal genome testing: its being a non-targeted type of testing, its high analytical validity, low clinical validity and problematic clinical utility. These characteristics raise their own specific ELSI, for example: non-targeted genetic profiling poses serious problems for information provision and informed consent. Questions about the quantity and quality of the necessary information, as well as about moral responsibilities with regard to the provision of information are therefore becoming central themes within ELSI-discussions of personal genome testing. Further, the current low level of clinical validity of genetic profiles raises questions concerning societal risks and regulatory requirements, whereas simultaneously it causes traditional ELSI-issues of clinical genetics, such as psychological and health risks, discrimination, and stigmatization, to lose part of their relevance. Also, classic notions of clinical utility are challenged by the newer notion of 'personal utility.' Summary: Consideration of test characteristics is essential to any valuable discourse on the ELSI of personal genome testing for multifactorial diseases. Four key characteristics of the test - targeted/non-targeted testing, analytical validity, clinical validity and clinical utility - together determine the applicability and the relevance of ELSI to specific tests. The paper identifies and discusses four areas of interest for the ELSI-debate on personal genome testing: informational problems, risks, regulatory issues, and the notion of personal utility

Perceived Impact of Diabetes Genetic Risk Testing Among Patients at High Phenotypic Risk for Type 2 Diabetes

Objective: Rapid advances in diabetes genetic epidemiology may lead to a new era of “personalized medicine” based on individual genetic risk assessment. There is minimal experience to guide how best to clinically implement such testing so that results (e.g., “higher” or “lower” relative genetic risk) improve rather than reduce patient motivation for behavior change. Research Design and Methods: Between November 2009 and May 2010, we conducted in-depth interviews with 22 overweight participants at high phenotypic risk for type 2 diabetes to explore perceptions of diabetes genetic risk testing compared with currently available prediction using nongenetic risk factors (e.g., family history, abnormal fasting glucose, obesity). We used hypothetical scenarios to specifically investigate the impact of both “higher” and “lower” relative genetic risk results on participants’ views about diabetes prevention. Results: Many participants conferred a unique value on personal genetic risk information relative to nongenetic risk based on the perceived scientific certainty and durability of genetic results. In contrast, other participants considered their genetic risk within the overall context of their other measured risk factors. Reactions to diabetes genetic test results differed by current motivation levels. Whereas most subjects reported that “higher” risk results would motivate behavior change, subjects with lower current motivation often reported that “lower” genetic risk results would further reduce their motivation to engage in diabetes prevention behaviors. Conclusions: To be effective, future clinical implementation of type 2 diabetes genetic risk testing should be individualized based on each patient’s risk perception and current level of motivation to prevent diabetes