Food Science and Technology Department
Department of Food Science and Technology: Faculty Publications
ORCID IDs
Document Type
Article
Date of this Version
5-25-2016
Citation
Cancer Epidemiology Biomarkers and Prevention (May 2016) 25(5): 869
doi: 10.1158/1055-9965.EPI-16-0063
Disclosure of Potential Conflicts of Interest: Huttenhower is a consultant/advisory board member for Seres Therapeutics. No potential conflicts of interest were disclosed by the other authors.
Abstract
We congratulate Sinha and colleagues on their recent report comparing fecal sample collection methods for epidemiologic studies of the gut microbiome. These data contribute to the increasing body of literature describing robust methodological frameworks for specimen collection and processing. However, their claim that fixation of stool using RNAlater® results in “considerable changes to the microbiome diversity” contrasts with previous findings, including those from their earlier reports. We have previously demonstrated that self-collected stool stabilized with RNAlater® or other fixatives yields high fidelity and reproducibility in compositional profiling of DNA and RNA from shotgun sequence data, compared to immediately-frozen specimens. Additionally, fixation offers several distinct advantages crucial for large-scale population-based studies: a straightforward self-collection procedure; sample stabilization without deep-freezing during shipping, receiving, and processing; and versatility for multiple molecular analyses. The authors’ finding that specimens preserved in RNAlater® had poor correlation with immediately frozen specimens could be explained, for example, by improper fixation resulting from an excess of specimen relative to preservative volume (1–2 g:2.5 ml, compared to the manufacturer-recommended ratio of 1 g:5–10 ml; Thermo Fisher Scientific Inc., Waltham, Massachusetts).
Comments
Copyright © 2016, American Association for Cancer Research. Used by permission