Removal of short sequence from DADA2 results

Technical Support
#1

Dear developer,
I perfomed dada2 for 16S amplicon sequences (341F-785R on MiSeq 300x2), and the result contained short sequences (about 260 bp).

qiime dada2 denoise-paired
–i-demultiplexed-seqs paired-end-demux.qza
–p-trim-left-f 17
–p-trim-left-r 21
–p-trunc-len-f 280
–p-trunc-len-r 230
–o-table table.qza
–o-representative-sequences rep-seqs.qza
–o-denoising-stats denoising-stats.qza

How can I remove shorter and longer sequences than expected?

Best,

#2

Hi @John9,

Could you clarify? Are you saying that your raw reads are shorter than 300 in some cases (i.e. some reads were sequenced through your reverse adapters and then ran out of molecule?) Or is something else the case?