Diagnostic testing

Diagnostic Testing vs. Predictive Testing:

Diagnostic testing is used to identify if an individual has a condition associated with symptoms they are showing. Predictive testing is used to search for gene changes associated with a condition before the individual develops symptoms.

The Genetic Testing Stories monograph is a collection of real stories from people who had all different types of genetic testing, including diagnostic testing.

If you think you need diagnostic testing, find a genetic counselor in your area to help you make the decision.

What Is Diagnostic Testing?

Diagnostic genetic testing can usually work out if you have a specific genetic condition that your provider is concerned about. It gives a “yes or no” answer. Your doctor may suggest a diagnostic genetic test if you have a medical problem. For example, people with a particular genetic condition may show symptoms similar to yours.

A diagnostic genetic test can:

  1. Diagnose the condition.
  2. Rule out the genetic condition as the cause of your health problem.
  3. Help prepare for other health concerns that may go along with the genetic condition.

Diagnostic genetic testing may help even if your doctor already has diagnosed the cause of your illness. Diagnostic testing can identify the particular genetic link to your condition.

Overall, diagnostic test results can help you and your doctor make choices about your treatment and care. Results also may help family members make healthcare decisions. Some genetic conditions run in the family, and others are “de novo” or start with the person who is affected. Figuring out if your condition is de novo or inherited can help other family members decide if they want to be tested, too.

Who Should Think about Diagnostic Testing?

You should think about diagnostic testing if:

  • You show signs of a problem, and
  • Your doctor wants to find out if a genetic condition is the cause of your health problem.
  • Your doctor is concerned you have a genetic syndrome and wants to be able to prepare for and manage other aspects of the syndrome.

Another way to diagnose your condition may exist. A genetic test is not always necessary. But, in some cases genetic testing may offer more information about your condition.


How Can I Get Diagnostic Testing?

Your doctor, a genetic specialist or a nurse practitioner can order diagnostic genetic testing. Your provider will make sure that the right test is ordered. Your provider also should explain to you what will happen during the testing and what the testing can and cannot tell you. See the genetic testing page for more details about the testing process.

Everyone should think carefully before being tested. A discussion with a genetic counselor can help you through this process. Be sure to talk about your results in depth with a healthcare professional so that you understand what the results mean for you now, in the future, and for your family.

Sometimes your doctor may think that you have a genetic disease, but diagnostic genetic testing is not available. In this situation the diagnosis is made clinically, or based on what the provider sees and observes. New tests are being developed as we learn more about disease and the cause of disease. A diagnosis is not a cure. However, it can help us better understand, prepare for, and treat our conditions.