Genetic testing is often considered to explain the cause of PAH and to identify if other family members are or are not at risk and accurately determine the risk of PAH in future children if that is a concern. The most commonly cited reason for genetic testing for PAH is to provide information to children. Pre-implantation genetic diagnosis has been used to avoid passing on the PAH gene to children once the familial mutation was identified, especially in families with childhood onset PAH.
Genetic testing identifies a genetic mutation in approximately 75% of PAH patients with a family history of PAH, most commonly in the gene BMPR2. A mutation is identified in approximately 20% of idiopathic PAH patients, even when there is no family history of PAH. Clinical genetic testing generally takes 4-8 weeks for results. Once the mutation in a family is known, testing other family members for a family-specific mutation is relatively inexpensive, accurate, and fast. Within a family, not everyone with the genetic risk will develop PAH. For BMPR2 carriers approximately 35% of women will develop PAH over a lifetime but only about 18% of men will develop PAH. Genetic testing is most helpful when it is able to identify members of the family who are not genetically at risk for PAH, and who can then forgo the otherwise recommended serial evaluations to screen for development of PAH. For at risk family members, regular screening by echocardiogram every 3 years and awareness of disease symptoms should enable early diagnosis and treatment which may improve outcomes.
There are sometimes concerns about discrimination or loss of insurance. For symptomatic individuals, there should be no concerns about genetic discrimination since any discrimination would be based upon a PAH diagnosis, not the genetic basis of the PAH. Asymptomatic individuals are protected under the Genetic Information Non-Discrimination Act (GINA) from having their health insurance access or rates changed based upon genetic test results. However, GINA does not provide protection again discrimination in life, disability, or long term care insurance although such discrimination has rarely been documented based upon genetic testing information alone. Genetic testing is available for PAH and should be considered in families to identify individuals who are at increased risk of developing PAH. Genetic testing is a personal choice.