DaehwanKimLab / hisat2

Graph-based alignment (Hierarchical Graph FM index)
GNU General Public License v3.0
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A question about methylation information extraction #417

Closed kekaiko closed 11 months ago

kekaiko commented 11 months ago

Hi hisat-3n developers,

Thank you for building this wonderful aligner!

I use hisat-3n to align my WGBS data with code : hisat-3n --index $Index_filename_prefix \ -q -1 $trim_read1 -2 $trim_read2 \ --base-change C,T \ --sensitive \ --threads 40 \ --no-spliced-alignment \ --time --met 3 \ --repeat \ --new-summary --summary-file "$summary_file" \ --directional-mapping-reverse | ~/anaconda3/envs/WGBS/bin/samtools view -@ 40 -b -q 10 -o $bam_file

Then the outputs are removing duplication by sambamba.

After that I use MethylDackel to extract my methylation information with parameter: --fraction.

Curiously, The methylation percentage is almost 100%.

My guess is it has to do with the "--directional-mapping-reverse".

Do you any suggestions? Best wishes