Doctors Should Tell Patients About Some, But Not All, Unexpected Genetic Findings

On Thursday, the American College of Medical Genetics and Genomics recommended that doctors tell patients about certain genetic disease risks if they accidentally find them when exploring a patient’s genome for another reason. However, the group does not recommend that doctors tell patients about all incidental findings.

The issue concerns many medical geneticists and other clinicians who use genome data in their practice. When a patient gets genetic testing to hunt for an explanation for heart trouble, should a doctor tell that patient if he or she sees a predisposition for breast cancer or early-onset Alzheimer’s disease?

It depends on the disease. The authors of the recommendation write that nearly 60 genetic variants, corresponding to more than 20 conditions, should be examined in all clinical sequencing tests. They say the recommended conditions are all likely to be verified by other diagnostic methods and can be addressed be some sort of medical intervention.

Many variants on the list increase a person’s risk of different kinds of cancer and could inform doctors and patients to start a more intensive tumor-screening process than most patients get. Other conditions that the ACMG says should be reported are familial hypercholesterolemia (high cholesterol), retinitis pigmentosa (which leads to blindness), and connective tissue disorders. Risk factors for Alzheimer’s disease (for which there is no medical intervention available) are not on the list. (The full list can be found starting on page 25 of the document linked above.)

The group does not exclude children or decisionally impaired adults in its recommendations—a parent or guardian should be informed in those cases, the authors write. However, it does specifically exclude fetuses.

The ACMG is blazing a trail with its recommendations, reports Nature:

“Few, if any, countries worldwide have developed such specific guidelines. “This is a pioneering effort,” says Muin Khoury, who heads the office of public-health genomics at the US Centers for Disease Control and Prevention in Atlanta, Georgia. And there is a need.”