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Genetic Testing
Overview of Genetic Testing
The term "genetic testing" covers an array of techniques including
analysis of human DNA, RNA or protein. Genetic tests are used as a health care
tool to detect gene variants associated with a specific disease or condition,
as well as for non-clinical uses such as paternity testing and forensics. In
the clinical setting, genetic tests can be performed to confirm a suspected
diagnosis, to predict the possibility of future illness, to detect the presence
of a carrier state in unaffected individuals (whose children may be at risk),
and to predict response to therapy. They are also performed to screen fetuses,
newborns or embryos used in in vitro fertilization for genetic defects.
Scientists are revealing ever more associations between particular gene mutations
and disease, and over a thousand tests can now determine whether a person carries
a particular disease-associated allele. As the number of tests continues to
rise, their use in the health care setting is becoming more commonplace. NHGRI
is funding research into innovative sequencing technologies so that, in a few
years, the sequencing of a patient's entire genome will be an affordable standard
diagnostic tool used in health care. Using genomic sequencing, it will be possible
to analyze all of a patient's genes to detect which disease-associated gene
variants they carry.
- A Brief Primer on Genetic Testing
A paper presented at the World Economic Forum in 2003 by Francis Collins.
Many genetic tests are marketed directly to consumers on the internet and
elsewhere. Some companies advertise clinical genetic tests directly to consumers.
This raises concern because it leads to instances where customers receive
clinically significant test results without appropriate counseling from a
health care professional, and are left to interpret complex results on their
own. Other companies offer tests and associated merchandise purported to help
clients select an optimal diet, stop smoking, or maintain a youthful appearance.
These claims lack sufficient scientific support to demonstrate their validity.
Several agencies are involved in oversight of genetic testing. The Centers
for Medicare and Medicaid Services (CMS) regulates clinical laboratory testing
to ensure laboratory compliance with the Clinical Laboratory Improvement Amendment
of 1988, showing accuracy and reliability in conducting assays. The Federal
Trade Commission (FTC) oversees advertising of tests and products. The Food
and Drug Administration (FDA) regulates tests sold as "diagnostic devices,"
that is, tests manufactured by one company and then sold as a kit to a laboratory
for genetic testing. However, the FDA does not regulate "home brew"
tests, that is, tests that are both manufactured and performed by the same laboratory.
Many common genetic tests (including the BRCA breast cancer gene tests) fall
into this category. Because of this regulatory exception, genetic testing services
using home brew tests can be marketed directly to the medical community - and
the public - without FDA regulation or oversight.
The Growth of Genetic Testing Raises Questions
- How should such tests be regulated? Should "home brew" tests be
regulated by the FDA just like diagnostic devices?
- What criteria should be used to determine whether a test can be patented
(See Intellectual Property and Genomics), and how do such patents affect scientific research?
- What level of analytical validity (accuracy of the test result), clinical
validity (use of the test as a diagnostic tool), or clinical utility (use
of test result for treatment) should be required for tests offered to the
public?
- What counseling should be provided for recipients of test results, and who
should provide that guidance?
- How can the public be protected from genetic discrimination?
Legislation on Genetic Testing
Legislation is being considered by Congress that would prohibit genetic discrimination
by employers or health insurance providers (See: Genetic Discrimination: Legislation).
Advisory Committees:
The Secretary's Advisory Committee on Genetics, Health, and Society (SACGHS) - staffed
by the National Institutes of Health (NIH) Office of Biotechnology Activities
- provides policy advice to the Department of Health and Human Services (DHHS)
on the broad array of complex medical, ethical, legal and social issues raised
by genetic testing.
NHGRI Interest in Genetic Testing
Concerns and Activities
Tests that detect gene variants associated with disease are diagnostic tools
that advance healthcare. Because of its increasing influence on public health,
the NHGRI is monitoring the development of genetic testing practices. NHGRI
is particularly interested in issues surrounding the establishment of clinical
utility and validity of such tests. As a member of SACGHS, NHGRI is participating
in designing advisory guidelines for the direct marketing of tests to consumers.
NHGRI is concerned that public fear of genetic discrimination is hindering scientific advances that would lead to diagnostic
genetic tests and drugs targeted to individuals with a specific genetic profile.
NHGRI is studying the possible effects of intellectual property on the future
of genetic testing and the integration of genomic medicine into health care
in the U.S.
Genetic counseling is important for those who are considering genetic testing.
NHGRI is interested in assuring high standards for the field and participates
in a joint training program for genetic counselors with Johns Hopkins University.
NHGRI is committed to helping ensure access to genetic counselors for those
in need.
Policy Recommendations
Discrimination in health insurance, and the fear of potential discrimination,
threaten both society's ability to use new genetic technologies to improve human
health and the ability to conduct the very research we need to understand, treat
and prevent genetic disease. NHGRI advocates for a federal resolution to the
public's concern that, by availing themselves to genetic tests, they risk being
discriminated against by employers and heath insurance providers (See: Genetic Discrimination).
NHGRI supports intellectual property [national academies.org] practices
that both enable research to advance and foster the development of genetic testing
products and associated medicines.
Reports on Genetic Testing
Last Updated: December 17, 2008
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