Fecal Sample Collection for Gut Microbiome Research in a Prospective Cohort: A Pilot Study within the Australian Breakthrough Cancer Study.

Large prospective analyses of human gut microbiome profiles are needed to elucidate the role of microbiome variation in the development of disease. We conducted a pilot study to assess the feasibility of home fecal sample collection within a cohort study. A subset of cohort study participants was randomly selected and randomized into four groups defined by fecal sample collection method and questionnaire components. Of 1,093 invited participants, 610 (56%) opted-in, and of those, 88% returned a sample. Of those asked to provide a fecal sample via fecal occult blood test (FOBT) card and complete a short "day-of-sample" questionnaire, 49% returned a sample. Sample return was comparable for participants additionally asked to provide a sample via ethanol tube (51%), complete a food frequency questionnaire (48%), or complete both additional activities (49%). Whole-genome sequencing and metagenomic analysis on paired FOBT and ethanol samples showed that both collection methods provided sufficient quality and quantity of DNA for downstream metagenomic analyses and displayed highly concordant microbiome profiles. Home fecal sample collection for microbiome analysis is feasible in a large prospective cohort. Including additional components did not reduce the likelihood of participants completing all requested items. SIGNIFICANCE: The expansion of this successful pilot to the larger Australian Breakthrough Cancer Study will facilitate future metagenomic and other host- and microbiome-related analyses in this large prospective cohort and potentially as part of an extended international pooling project.