Should people who volunteer for genomic studies be told about unrelated disease mutations that turn up in their sequence data? The decadeslong debate about such “incidental findings,” which can include genes that boost risk for cancer or heart disease, flared up again last week after bioethicists at the National Institutes of Health (NIH) published a study showing many participants who at first refuse those findings can change their minds. Controversially, it went on to suggest all research participants should routinely be told about their genetic risks for conditions that can be prevented or treated—a change from current practice.

The controversy pits researchers, many of them physicians, who see incidental findings as an opportunity to boost the health of the millions who have had their genomes analyzed, against others, mainly bioethicists, who stress the need to respect study participants’ hesitation about receiving information that might expose them to genetic discrimination or simply be unwelcome. Deepening the divide, the study showed Black participants were more likely to refuse incidental results. “That strengthens the argument for saying we’ve really got to get true consent, opt-in consent from everyone,” says Susan Wolf, a lawyer who teaches health law and bioethics at the University of Minnesota  Law School.

In the study, researchers re-contacted research participants in a large NIH study 1 to 3 years after they enrolled. Initially, 1.9% of participants had declined to receive incidental findings. The team reports in Genetics in Medicine that of the 83 initial refusers, 41 changed their minds and accepted after being presented with new information, including an assurance that researchers would only return results on genes that raised the risk for serious conditions that were preventable or treatable, such as cancer and heart disease. (Six participants who initially accepted the findings changed their minds and refused after being reapproached.)