Genetic Testing
Overview
Genetic testing, also known as DNA 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.
Types of Genetic Testing
There are several types of genetic testing that are commonly used today. These include:
- 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.
Process of Genetic Testing
The process of genetic testing involves the collection of a sample of blood, hair, skin, amniotic fluid (the fluid that surrounds a fetus during pregnancy), or other tissue. The sample is then sent to a laboratory where technicians look for specific changes in chromosomes, DNA, or proteins, depending on the suspected disorder. The laboratory reports the test results in writing to a person's doctor or genetic counselor.
Benefits and Risks of Genetic Testing
The potential benefits of genetic testing include a confirmed diagnosis, an early diagnosis, and the ability to make informed decisions about managing health care. For some people, test results can help them make decisions about having children. Genetic testing can also provide information for diagnosing, treating and managing a person’s illness or disease.
However, genetic testing has limitations and risks as well. The test might not be able to provide helpful information about a person's condition, or it might produce uncertain results. Genetic testing can also be emotionally uncomfortable and cause people to worry about their health. It can also have serious financial and social implications.
Ethical, Legal, and Social Implications
Genetic testing raises many ethical, legal, and social issues. Genetic information can be sensitive because it might affect a person's chances of getting certain jobs or insurance. Some people might choose not to have genetic testing because they fear discrimination. However, in the United States, the Genetic Information Nondiscrimination Act (GINA) helps protect people from health insurance or employment discrimination based on their genetic information.
Future of Genetic Testing
The future of genetic testing is likely to involve more widespread use of whole genome sequencing, a process that determines the complete DNA sequence of an organism's genome at a single time. This could provide a more complete picture of a person's genetic makeup and could potentially identify genetic mutations that could lead to disease.