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How are genetic conditions diagnosed?
A doctor may suspect a diagnosis of a genetic condition on the basis of a person’s physical characteristics and family history, or on the results of a screening test.
Genetic testing is one of several tools that doctors use to diagnose genetic conditions. The approaches to making a genetic diagnosis include:
Genetic testing is currently available for many genetic conditions. However, some conditions do not have a genetic test; either the genetic cause of the condition is unknown or a test has not yet been developed. In these cases, a combination of the approaches listed above may be used to make a diagnosis. Even when genetic testing is available, the tools listed above are used to narrow down the possibilities (known as a differential diagnosis) and choose the most appropriate genetic tests to pursue.
A diagnosis of a genetic disorder can be made anytime during life, from before birth to old age, depending on when the features of the condition appear and the availability of testing. Sometimes, having a diagnosis can guide treatment and management decisions. A genetic diagnosis can also suggest whether other family members may be affected by or at risk of a specific disorder. Even when no treatment is available for a particular condition, having a diagnosis can help people know what to expect and may help them identify useful support and advocacy resources.
For more information about diagnosing genetic conditions:
Genetics Home Reference provides information about genetic testing and the importance of family medical history. Additionally, links to information about the diagnosis of specific genetic disorders are available in each condition summary under the heading “Where can I find information about diagnosis or management of...?”
The National Center for Biotechnology Information (NCBI) provides an in-depth guide called Understanding
The Centers for Disease Control and Prevention (CDC) offers a fact sheet about the diagnosis of birth
Boston Children’s Hospital provides this brief overview of testing for genetic
The American College of Medical Genetics offers practice
The Agency for Healthcare Research and Quality’s (AHRQ) National Guideline Clearinghouse has compiled screening, diagnosis, treatment, and management