["Bioethics, EarlyView. ", "\nABSTRACT\nGenome editing in human embryos could raise new ethical issues by changing future people's narrative and numerical identity. Most philosophers agree that some genetic modifications would have larger effects on identity than others, but they disagree on what criteria might explain these differences and have not supported their claims experimentally. We recruited 416 Americans through the crowdsourcing website Mechanical Turk. Participants were presented with 30 genetic modifications commonly discussed in bioethics and completed a questionnaire about how each modification might affect future people's narrative identity and social treatment. Perceived effects of genome editing on narrative identity correlate moderately with effects on social treatment, suggesting a large role for social construction. The largest changes to identity were associated with changing biological sex, enhancing intelligence, adding abilities from other species and introducing or preventing deafness. The smallest changes to identity were from making people right‐handed, lowering the need for sleep, preventing dementia and changing eye or hair colour. Modifications of the same characteristic in opposite directions, such as making someone more or less aggressive, generally had significantly different effects on societal treatment but not on narrative identity. Specifying gender by describing the genetically modified person as a ‘son’ or ‘daughter’ did not have significant effects. These findings offer a new direction for research on genome editing and the identity of genetically modified people.\n"]