Demulitplexing issue

[Nicholas_Bokulich]

@ben

Also, there’s an option to disable Golay barcodes.

@Vandana please see this topic for more description of disabling golay error correction (which you should do if your reads are not golay barcodes, e.g., if you are not following the EMP protocol):

Clarification of a bug/or not a bug? qiime2 demux with little reads (2019.4 version to 2019.7 version)

Hi @ben! I think the parameter you are referring to is --p-no-golay-error-correction Nope, not a fluke, just poorly described. Let me try and summarize! Without Golay error correction, it doesn't matter the orientation your barcodes sequences are in, so long as they are the same orientation as the barcode mapping in your metadata file. If they aren't, you can use --p-rev-comp-barcodes to reverse complement the barcode sequences to match the barcode map OR use the --p-rev-comp-mapping…

@Vandana

This data set is already analysed in Usearch but not in Qiime

That helps, since you should know the correct orientations for demultiplexing and can adapt whatever parameters you used in that analysis. As I suggested above:

@Nicholas_Bokulich

it is just a matter of figuring out the orientation of your barcode reads and whether any actually match your EMP barcodes.