A genetic test examines the
DNA (deoxyribonucleic acid) of a person's cells.
Genetic testing can identify changes in
genes or can analyze the number, arrangement, and
characteristics of the
The results of genetic
testing depend on the type of test done. Genetic testing is used to:
- Diagnose an inherited
- Provide information about how likely it is that you will
develop a disease in the future.
- Determine whether you are a
carrier of the disease.
- Provide information about the severity of
an inherited disease.
- Help choose appropriate treatment for some
diseases, such as
HIV infection or some types of cancer.
What Affects the Test
Having a blood transfusion
within a week before the test can interfere with your test or the accuracy of
What To Think About
The information obtained from a
genetic test can have a profound impact on your life. Genetic counselors are
trained to help you understand your risk for having a child with an inherited
(genetic) disease, such as
sickle cell disease,
cystic fibrosis, or
genetic counselor can help you make well-informed
decisions. Ask to have
genetic counseling before making a decision about
- A genetic test result is sensitive information.
Your confidentiality should be maintained, and the release of information
should be limited to those who are authorized to receive it.
- The discovery of a genetic disease that is not causing symptoms
now (such as breast cancer or Huntington's disease) should not affect your
future ability to gain employment or health insurance coverage. A law in the
United States, called the Genetic Information Nondiscrimination Act of 2008
(GINA), protects people who have DNA differences that may affect their health.
This law does not cover life insurance, disability insurance, or long-term care
- A genetic test can
sometimes reveal unintended information, such as the identity of a child's
fetal genetic test may detect a serious disease or disorder (such as
Down syndrome) that will greatly impact your child's
life and the lives of caregivers. A pregnant woman who is considering genetic
testing may want to consider her ethical, social, and religious beliefs to help
her determine the actions she would take if test results are positive.
- A karyotype can be used to examine the size, shape, and number of
chromosomes. Extra or missing chromosomes, or abnormal positions of chromosome pieces, can
cause problems with a person's growth, development, and body functions. To learn more, see the topic
- A breast cancer (BRCA) gene test is done to
evaluate your risk of developing breast cancer. To learn more, see the
Breast Cancer (BRCA) Gene Test.
- A type of genetic test (DNA fingerprinting) can be used to
determine paternity, help solve crimes, and identify a body. DNA fingerprinting
is more accurate than dental records, blood type, or traditional fingerprints.
To learn more, see the topic