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bioRxiv · 10.1101/2020.03.07.982314

mbImpute: an accurate and robust imputation method for microbiome data

Jiang, R.·Li, W. V.·Li, J. J.
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Abstract

Microbiome studies have gained increased attention since many discoveries revealed connections between human microbiome compositions and diseases. A critical challenge in microbiome research is that excess non-biological zeros distort taxon abundances, complicate data analysis, and jeopardize the reliability of scientific discoveries. To address this issue, we propose the first imputation method, mbImpute, to identify and recover likely non-biological zeros by borrowing information jointly from similar samples, similar taxa, and optional metadata including sample covariates and taxon phylogeny. Comprehensive simulations verified that mbImpute achieved better imputation accuracy under multiple measures than five state-of-the-art imputation methods designed for non-microbiome data. In real data applications, we demonstrate that mbImpute improved the power and reproducibility of identifying disease-related taxa from microbiome data of type 2 diabetes and colorectal cancer.

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Jiang, R., Li, W. V., Li, J. J.. 2020-03-08. mbImpute: an accurate and robust imputation method for microbiome data. https://doi.org/10.1101/2020.03.07.982314

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