“Some families are really open about sharing, and others aren’t,” says Anne Frankl, a genetic counselor at UnityPoint Health in Des Moines. “It’s an ethical conundrum if your family isn’t open. You’re wondering ‘Am I doing the right thing by telling people or not telling people? Am I being disruptive to their lives?’”

When Julie Gregory had her DNA analyzed by a testing company in 2012 and learned that she carried two copies of the gene that’s linked to Alzheimer’s disease, she tearfully told her family the news. She didn’t realize she inadvertently revealed a family trait they hadn’t been aware of: the AOPE4 gene is hereditary, and they were all potentially at risk.