When a doctor orders a genetic test, patients assume that the test will yield a useful result to guide how their physicians take care of them. That assumption is frequently correct, but not always. Until recently, a genetic test only interrogated the sequence of one or two genes. Now, DNA-sequencing technologies are so fast and cheap that they have enabled clinicians to sequence panels of genes that may or may not be relevant to the patient's condition. The technology has outpaced our ability to interpret the results. Connecting approval of clinical tests to data sharing could help close this gap.