And some enforce their patents aggressively: Myriad Genetics, which holds the patents on the BRCA1 and BRCA2 genes responsible for most cases of hereditary breast and ovarian cancer, charges $3,000 to test for the genes. Myriad has been accused of creating a monopoly, since no one else can offer the test, and researchers can’t develop cheaper tests or new therapies without getting permission from Myriad and paying steep licensing fees.