OTU vs. ASV is a critical choice in targeted (e.g. 16S) microbiome sequencing. This blog and video will help you understand the key differences in these methods, whether you are a beginner to microbiome analysis or already have experience.

Feb 24, 2022 · We compared the effects of ASV vs. OTU approaches using two different identity thresholds to those with varying levels of sequence rarefaction, and eight contrasting alpha and beta-diversity metrics.

One pipeline (VSEARCH) employs clustering methods, generating individual operational taxonomic units (OTUs), while the other (DADA2) is based on sequencing error correction algorithms and generates exact amplicon sequence variants (ASVs). The outcomes of both pipelines were compared within the framework of ecological-driven data analysis.

Jul 21, 2017 · Recent advances have made it possible to analyze high-throughput marker-gene sequencing data without resorting to the customary construction of molecular operational taxonomic units (OTUs):...

The detection of true biological and ecological variations appears to be robust to the choice of sequencing processing method (OTU vs. ASV) in a few studies on soil, mouse feces, and human intestinal biopsies [12–14], but head-to-head comparisons are …

Feb 24, 2022 · We compared the respective influences of two widely used methods, namely DADA2 (a denoising method) vs. Mothur (a clustering method) on 16S rRNA gene amplicon datasets (hypervariable region v4), and compared such effects to the rarefaction of the community table and OTU identity threshold (97% vs. 99%) on the ecological signals detected.

Oct 3, 2024 · Two levels of progressive OTUs clustering, (99% and 97%) were compared with the ASV data. The results showed that the OTUs clustering proportionally led to a marked underestimation of the ecological indicators values for species diversity and to a distorted behaviour of the dominance and evenness indexes with respect to the direct use of the ...

Oct 3, 2024 · In this work, dealing with bacteria, we sought to address particularly the aspect of OTUs vs. ASV handling, which can be critical for the applied aspects of environmental impact assessment, or to measure the effects of different agricultural management practices on soil ecology, as well as to compare between natural and anthropized landscapes ...

Jul 13, 2022 · OTU and ASV are used for taxonomic identifications in amplicon sequencing. OTU is rounding sequences to a percent similarity reading where ASV is to specific sequences. ASV gives better resolution, OTU is outdated at this stage.

Define and explain the concepts of metadata, OTU, rarefaction curve. A definition of rarefaction curves and why we use them: https://blogs.iu.edu/ncgas/2019/09/04/rarefaction-curves-for-metagenomic-datasets/ Rarefying data can be “controversial.”