smithlabcode / falco

A C++ drop-in replacement of FastQC to assess the quality of sequence read data
https://falco.readthedocs.io
GNU General Public License v3.0
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falco doesn't consider BAM flag bits #59

Open wm75 opened 1 week ago

wm75 commented 1 week ago

It seems that falco doesn't handle reverse-complemented read sequences in mapped BAM files correctly. Specifically, when flag bit 0x04 of a read is not set (i.e. when the read is mapped), falco should consider the status of the 0x10 bit and reverse-complement the sequence if that bit is set.

Example output of falco (multiqc visualized) on just the reverse-strand reads from a mapped bam:

image

and those same reads analyzed with fastqc:

image