Hello,

I downloaded the files from: https://bigd.big.ac.cn/gsa/

The file is ended with:  " *._f1.fq.gz" and " *._r2.fa.gz".

1. Is it single-end or paired-end sequencing?

2. If it is paired-end sequencing, the file should be:   " *._r1.fq.gz" and " *._r2.fa.gz", not " *._f1.fq.gz".

Thanks in advance for any help!

Best,


Yue


> If it is paired-end sequencing, the file should be: "._r1.fq.gz" and "._r2.fa.gz", not "*._f1.fq.gz".

There are no hard rules regarding the labeling of paired files, which is most likely what yours are. And if there are rules, they are not followed by everyone. In your case, these files are likely `forward` (r1) and `reverse` (r2). It is not difficult to verify this after you unpack the files and type:

    head *_??.fq

If both files have similar headers except where one of them has `1` the other has `2`, they are paired-end files.