The best definition of a genetic test comes from the US National Library of Medicine (USNLM):
Genetic testing is a type of medical test that identifies changes in chromosomes, genes, or proteins. The results of a genetic test can confirm or rule out a suspected genetic condition or help determine a person’s chance of developing or passing on a genetic disorder. More than 1,000 genetic tests are currently in use, and more are being developed.
Several methods can be used for genetic testing:
- Molecular genetic tests (or gene tests) study single genes or short lengths of DNA to identify variations or mutations that lead to a genetic disorder.
- Chromosomal genetic tests analyze whole chromosomes or long lengths of DNA to see if there are large genetic changes, such as an extra copy of a chromosome, that cause a genetic condition.
- Biochemical genetic tests study the amount or activity level of proteins; abnormalities in either can indicate changes to the DNA that result in a genetic disorder.
Genetic testing is voluntary. Because testing has benefits as well as limitations and risks, the decision about whether to be tested is a personal and complex one. A geneticist or genetic counselor can help by providing information about the pros and cons of the test and discussing the social and emotional aspects of testing.
- What is genetic testing?
- What are the types of genetic tests?
- How is genetic testing done?
- What is direct-to-consumer genetic testing?
- How can consumers be sure a genetic test is valid and useful?
- What do the results of genetic tests mean?
- What is the cost of genetic testing, and how long does it take to get the results?
- Will health insurance cover the costs of genetic testing?
- What are the benefits of genetic testing?
- What are the risks and limitations of genetic testing?
- What is genetic discrimination?
- How does genetic testing in a research setting differ from clinical genetic testing?
- What is genetic ancestry testing?
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- NLM National Library of Medicine