demux emp-paired error: No sequences were mapped to samples.

Hello,

I am trying to run an analysis on the pair-end data that is multiplexed. I used qiime1(extract_barcodes.py) to generate barcode file, and imported the data use qiime2(version:2019.10.0) . When demuxing using qiime2, I could not suceed. These are my commands and error messages:

qiime demux emp-paired
–m-barcodes-file sample-metadata.tsv
–m-barcodes-column barcode-sequence
–p-no-golay-error-correction
–p-rev-comp-mapping-barcodes
–i-seqs emp-paired-end-sequences.qza
–o-per-sample-sequences demux.qza
–o-error-correction-details demux-detail.qza

Plugin error from demux:
No sequences were mapped to samples. Check that your barcodes are in the correct orientation (see the rev_comp_barcodes and/or rev_comp_mapping_barcodes options).
Debug info has been saved to /tmp/qiime2-q2cli-err-nttlh1wa.log

I tried every combination of adding the reverse complement barcodes/ reverse complement mapping barcodes options but they all give me the same error as above.
I also checked the barcodes and sequences files, which are not swapped. The 'sequences.fastq.gz` did not contain the barcodes.

Thanks very much.

Hello Matthew,

Could you help me to solve this problem? I have posted it on the forum,but no answers. I could not proceed before working out the following problem.

I am trying to run an analysis on the pair-end data that is multiplexed. I used qiime1(extract_barcodes.py) to generate barcode file, and imported the data use qiime2(version:2019.10.0) . When demuxing using qiime2, I could not suceed. These are my commands and error messages:

qiime demux emp-paired
–m-barcodes-file sample-metadata.tsv
–m-barcodes-column barcode-sequence
–p-no-golay-error-correction
–p-rev-comp-mapping-barcodes
–i-seqs emp-paired-end-sequences.qza
–o-per-sample-sequences demux.qza
–o-error-correction-details demux-detail.qza

Plugin error from demux:
No sequences were mapped to samples. Check that your barcodes are in the correct orientation (see the rev_comp_barcodes and/or rev_comp_mapping_barcodes options).
Debug info has been saved to /tmp/qiime2-q2cli-err-nttlh1wa.log

I tried every combination of adding the reverse complement barcodes/ reverse complement mapping barcodes options but they all give me the same error as above.
I also checked the barcodes and sequences files, which are not swapped. The 'sequences.fastq.gz` did not contain the barcodes.

Thanks very much.

Hi @terren - hopefully @ebolyen will get a chance to reply soon.

In the meantime, please consult with your sequencing center, they can tell you the orientation of barcodes and reads, which will help you make the decision on which flags to use.

:qiime2:

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