Unusual feature table generated by joined reads without errors reported

I am a new Qiime 2 user. When analyzing joined reads (result from QIIME1 by running convert_fastaqual_fastq.py), I met some troubles. No error was reported. However, the results of feature table and rep-seqs seemed not right. Each feature was observed in one sample! It is unusual and I don’t know how to deal with it.

The screenshots are shown as fellows and data were attached.

data: https://cloud.tsinghua.edu.cn/f/465d8da6b24b4d329b80/?dl=1

It would be great if some help can be provided.

Thank you in advance.

Hi @Jiaying,
Without having looked at your actual data my first guess is that this is an issue of non-biological reads, particularly, barcodes not being removed from your reads. Have you made sure to remove the barcodes (and any other non-biological sequences) from your reads?

Hi @Mehrbod!
Thank you very much! When using Deblur, “–p-left-trim-len 15” was missed.
Now, all is OK!

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