High number of reads in blank controls for Amplicon sequencing data?

20 May 2022 0 2K Report

Hi Community,

Recently I have submitted samples for amplicon and found an unusually high number of reads being present in my negative control blank samples. Yet, when I ordinated those samples in PCA, Negative controls stand out completely from my actual samples, indicating this might be something different. Did anyone faced such issues with negative control for 16S amplicon and can suggest me possible explanations. I used a positive control mock community which is giving me desired result. I wonder how could this happen?

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