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- Inadequate discussion or patient counseling
- Reduced opportunity for internal and external quality assurance, with associated
risk of misdiagnosis - Medicolegal implications
Future Prospects of Point-of-Care Diagnosis
POC-testing is destined to become a major force in the development of healthcare
delivery. Currently, POC devices account for approximately a quarter of the world-
wide market for clinical laboratory IVD products. Advances will be on four fronts:
- Scope: expanding the POC format into new categories of in vitro diagnostic
testing - Connectivity: communicating test results externally with ease and fl exibility
- Non-invasiveness: improving the way test samples are obtained from the body.
- Miniaturization: reducing the size of the devices to enable novel uses
The major technological requirements to reduce complications of POC have
been identifi ed by both the manufacturers and the regulators. These focus on reduc-
tion of dependence on the operator and seamless automation of quality control.
Genetic Testing for Disease Predisposition
Genetic testing is a broad term, which covers several techniques, including those
used to determine paternity and in forensic medicine. However, most genetic tests are
used to confi rm a suspected diagnosis, to predict susceptibility to an illness, to iden-
tify individuals who carry a specifi c genetic mutation but remain unaffected them-
selves, or to predict how an individual is likely to respond to a certain therapy.
Genetic tests are also used to screen fetuses, newborns, and embryos used in in vitro
fertilization for genetic defects. Over 1,800 genetic tests are available including those
that indicate susceptibility to cancer, neurological disorders, and heart disease.
An understanding of the disease-related effects of specifi c genetic variants pro-
vides the basis for direct genetic testing in individuals and alleviates reliance on
population categories to improve disease diagnosis and treatment (Rotimi and Jorde
2010 ). Testing for gene mutations that confer susceptibility to adult-onset disorders
has potential benefi ts, but these must be balanced against the psychological harms,
if any. The published fi ndings on the psychological effects of such testing, focusing
on Huntington’s disease, which has the most available data, and the hereditary can-
cer syndromes. Most of the evidence suggests that non-carriers and carriers differ
signifi cantly in terms of short-term, but not long-term, psychological adjustment to
test results. The psychological impact of genetic testing depends more on pretest
psychological distress than the test result itself.
2 Molecular Diagnostics in Personalized Medicine