Nature 549, 48–53 (2017); doi:https://doi.org/10.1038/nature23874

In this Article, the description in the Methods of the human stool samples used for the analysis presented in Extended Data Fig. 9 was incomplete. All samples were collected with informed consent under protocol numbers 09-067, 09-141 and 06-107 at Memorial Sloan Kettering Cancer Center (MSKCC) and stored as part of a biospecimen repository. All sample processing was done at MSKCC. All patients underwent a bone marrow transplant which was standard of care and part of an observational study (not a clinical trial, as originally stated in the Methods). Patient age, gender and transplant indication are provided in the table now added to Extended Data Fig. 9. The Reporting Summary has been updated (the original uncorrected Reporting Summary is provided as the Supplementary Information to this Corrigendum). The original Letter has been corrected online.