658
A commentary in the Journal of American Medical Association offers several
caveats and recommendations to help doctors and counselors as they consider offer-
ing these research-based tests in clinical practice (Offi t 2008 ):
- There is concern about the scientifi c accuracy of some of these tests, because
they have not yet been validated in prospective clinical studies. In addition, the
laboratory accuracy of these tests may vary. - Direct to consumer aspect of the marketing of these tests excludes guidance from
healthcare professionals. This limits the sources of information available to con-
sumers about these tests and their accuracy from those marketing the tests. This
critical lack of information raises concerns that patients/individuals may not
have the resources to make unbiased decisions regarding whether to proceed
with genetic testing. - Once these self-ordered test results are relayed, individuals receiving the results
may not receive counseling regarding appropriate medical interventions for pre-
vention and early detection of genetic disorders.
A follow-up of selected sample subjects who went DTC genomewide testing,
there were no measurable short-term changes in psychological health, diet or exer-
cise behavior, or use of screening tests (Bloss et al. 2011 ). A study by the Mayo
clinic showed that predictive genomic risk information from DTC testing modestly
infl uences risk perception and worry; the extent and direction of this infl uence may
depend on the condition being tested and its baseline prominence in preventive
health care, which may attenuate with time (James et al. 2011 ). The concern of the
medical profession about the potential harm of DTC is refl ected in the following
comments (Annes et al. 2010 ): - Most genetic screening currently cannot meet the expectations of established
principles in order to avoid undue harm and expense and may place a substantial
burden on the health care system without providing demonstrable benefi t. - US Government Accountability Offi ce’s investigative report in 2010 cited erro-
neous medical management advice from DTC genetic-testing companies, and a
lack of standardization of results – clinically valid tests for the same condition
should yield concordant results. - Potential harms of DTC genetic testing include the loss of protections for patients
offered by established health care delivery systems such as doctor–patient confi -
dentiality, invalid analytic or clinical results from medical devices, and popula-
tion screening without consensus on interpretation and follow-up.
Privacy Issues in Personalized Medicine
Genetic tests challenge privacy depending on how comprehensive the test is and how
the access to samples or digital information is controlled. Point-of-care (POC) tests
are likely to be limited in scope, fi t seamlessly into medical records and do not raise
new ethical and privacy challenges. Large-scale clinical trials, on the other hand,
21 Ethical Aspects of Personalized Medicine