Under what circumstances should one take a genetic test?

Not everyone needs to be genetically tested for IRDs. Below are the most common reasons individuals are advised to take a genetic test:

With respect to IRDs, diagnostic testing is used to confirm a clinical diagnosis made by an ophthalmologist. Studies have shown that 15% of clinical diagnoses change after genetic testing. This is due to the similar clinical presentation of some IRDs. A genetic test is the only method of definitively diagnosing an IRD.

Carrier testing is frequently carried out in individuals with a family history of a genetic disorder, to determine if they carry a mutated recessive allele for an IRD. Usually the carrier will not be affected by symptoms of the disease, nor is at risk of developing them, but may seek the information to make informed reproductive choices.

In the case of IRDs, a predictive test is recommended to a patient if a specific disease-causing mutation has been identified in an affected family member. This enables the patient, regardless of whether they are demonstrating symptoms of that genetic condition, to establish whether they have the same mutation, and if they are at risk of developing the condition later in life. Even in the absence of medical interventions, predictive testing can influence life-planning decisions.