The last decade has seen a tremendous expansion of
scientific knowledge in human genetics. Our understanding of human genes
and of the genetic basis of disease has grown dramatically. Currently,
more than 4,000 diseases such as sickle cell anemia and cystic fibrosis
are known to be genetic and are passed on in families. Moreover, it is now
known that alterations in our genes play a role in such common conditions
as heart disease, diabetes, and many types of cancer.
The identification of disease-related genes has led to an increase in
the number of available genetic tests that detect disease or an
individual's risk of disease. As of this writing, gene tests are available
for many disorders, including Tay-Sachs disease and cystic fibrosis. New
tests are being developed to detect predispositions to Alzheimer's
disease, colon cancer, breast cancer, and other conditions.
As the number of available genetic tests increases, the use and
interpretation of those tests and the information they generate will
require a basic understanding of how genetic principles apply to different
health problems such as cancer. Scientists are concerned not only that
gene tests offered are reliable, but also that patients and health care
professionals understand the limitations of such testing. The disclosure
of test results could inflict psychological harm to a patient if safe and
effective interventions are not also available.
Understanding Gene Testing represents an effort by the National
Cancer Institute and the National Center for Human Genome Research to
provide basic information about gene testing and key genetic concepts.
This booklet also provides answers to a number of frequently asked
questions about the science, potential benefits, and potential risks of
gene testing.
As the relationships between genes and health become better understood
and new genetic technologies are developed, additional information about
gene testing and related issues will become available. Both the National
Cancer Institute and the National Center for Human Genome Research will
work hard to keep you up to date.
