Daniel:Notebook/GenomeMiner/2013-8-7
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HL155
Continuing the analysis of the HL155 data. I looked through the information on the bowtie2 manual. The 12th column of a SAM output contains several possibly useful pieces of information:
From Bowtie2 manual
XM:i:<N> The number of mismatches in the alignment. Only present if SAM record is for an aligned read. NM:i:<N> The edit distance; that is, the minimal number of one-nucleotide edits (substitutions, insertions and deletions) needed to transform the read string into the reference string. Only present if SAM record is for an aligned read.
Basically, these should be able to give me an idea of the number of mismatches. I'm not really sure yet whether XM or NM is better, so I'm taking them both. First I awked the data from the 3rd, and 12-20th columns.
Awk Command
awk '{print $3,\t,$12,\t,$13,\t,$14,\t,$15,\t,$16,\t,$17,\t,$18,\t,$19,\t,$20}' hcrp_onlymapped_hl155.sam > /home/djacobse/hl155/hl155_3_12_andbeyond.txt
Perl Script
#!usr/bin/perl use strict; use warnings; #should count the NM:i:digit column of the script and return #the probe name, mismatches, and edit number open READS, "hl155_3_12_andbeyond.txt"; while (<READS>) { my($probe)=$_=~/(Probe_set\d_\d\d?\d?\d?\d?)/; my($mismatch) = $_ =~/(XM:i:\d)/; my($mismatch2)= $mismatch =~ /(\d)/ ; my($editnum)= $_ =~ /(NM:i:\d)/; my($editnum2) = $editnum =~ /(\d)/; print $probe."\t".$mismatch2."\t".$editnum2."\n"; }