Nature - 2019.08.29

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nature research | reporting summary

October 2018

Human research participants

Policy information about studies involving human research participants

Population characteristics Patients undergoing allogeneic hematopoietic stem cell transplantation were receiving care at Memorial Hospital. Healthy

human donors were employees of Memorial Sloan Kettering who consented to providing fecal samples for sequence analyses

and for culture.

Recruitment Patients were informed of the fecal collection study and consent was obtained prior to initiation of hematopoietic stem cell

transplantation. Healthy donors were informed of the study and consent was obtained to perform sequencing studies of fecal

samples and to culture bacterial species from the fecal sample.

Ethics oversight The fecal collection protocol and the healthy human donor protocol were approved by the Memorial Sloan Kettering

Institutional Review Board.

Note that full information on the approval of the study protocol must also be provided in the manuscript.