Genetic Testing
While genetic screening tests do not provide a conclusive answer, they can help guide next steps, such as whether additional, diagnostic testing is needed.
Abstract
Screening tests evaluate an individual’s risk of developing a genetic condition, while diagnostic tests identify genetic conditions. All genetic tests have both benefits and limitations. Genetic screening tests are generally used in people who do not have signs or symptoms of a disorder. These tests estimate whether an individual’s risk of having a certain condition is increased or decreased compared with the risk in other people in a similar population. A positive result means that a person’s risk of developing the condition is higher than average. A negative screening test means that a person’s risk is lower than average. However, having a positive screening result does not mean the individual has the condition. Because screening tests are only estimates, in some cases the results indicate an increased risk for a genetic abnormality when the person is actually unaffected (false positive), or the results indicate a decreased risk for a genetic abnormality when the person is really affected (false negative). While genetic screening tests do not provide a conclusive answer, they can help guide next steps, such as whether additional, diagnostic testing is needed. Genetic diagnostic tests are often used in people who have signs and symptoms. These tests are used to confirm or rule out suspected genetic conditions. Diagnostic tests can also help inform a person’s chance of developing a genetic condition or of passing on a genetic condition to their children. Diagnostic testing can be performed before birth or at any time during a person's life