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1 #!/usr/bin/env python
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2
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3 #PRADA: Pipeline for RnAseq Data Analysis
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4 #Fusion detection module, algorithm published by Michael Berger et al (Genome Res, 2010) at Broad Institute.
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5 #Implemented by Siyuan Zheng, Wandaliz Torres-Garcia and Rahul Vegesna.
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6 #Copy Right: The Univ of Texas MD Anderson Cancer Center, Department of Bioinformatics and Computational Biology
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7 #Contact: Roel Verhaak (rverhaak@mdanderson.org)
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8 #Citation: to be added
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9 #Tested with Python v2.6 and v2.7
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10 #The program requires NM tag and high quality mapping reads with mapping score more than -minmapq.
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11 #Last modified: 04/11/2013
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12
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13 ######################################################################################
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14 import sys
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15 import time
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16 import os
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17 import os.path
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18 import subprocess
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19 import operator
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20 import pysam
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21 import bioclass
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22 import gfclass
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23 import ioprada
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24 import privutils
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25 from Bio import SeqIO,Seq
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26
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27 ######################################################################################
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28 args=sys.argv
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29
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30 help_menu='''\nPipeline for RNAseq Data Analaysis - fusion detection (PRADA).
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31 **Command**:
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32 prada-fusion -bam XX.bam -conf xx.txt -tag XX -mm 1 -junL XX -minmapq 30 -outdir ./
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33 **Parameters**:
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34 -h print help message
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35 -bam input BAM file, must has a .bam suffix. BAM is the output from PRADA preprocess module.
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36 -conf config file for references and parameters. Use conf.txt in py-PRADA installation folder if none specified.
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37 -tag a tag to describe the sample, used to name output files. Default is ''.
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38 -mm number of mismatches allowed in discordant pairs and fusion spanning reads.Default is 1.
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39 -junL length of sequences taken from EACH side of exons when making hypothetical junctions. No default.
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40 -minmapq minimum read mapping quality to be considered as fusion evidences. Default is 30.
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41 -outdir output directory.
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42 -v print version
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43 '''
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44
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45 if '-h' in args or '-help' in args or len(args)==1:
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46 print help_menu
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47 sys.exit(0)
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48
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49 if '-v' in args:
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50 import version
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51 print version.version
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52 sys.exit(0)
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53
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54 if '-bam' not in args:
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55 sys.exit('ERROR: BAM file needed')
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56 i=args.index('-bam')
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57 bampath=args[i+1]
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58 bampath=os.path.abspath(bampath)
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59 bam=os.path.basename(bampath)
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60 if bam[-4:] != '.bam':
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61 sys.exit('ERROR: BAM file must have suffix .bam')
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62
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63 #Mismatch allowed. This filter is applied at the very end of the pipeline.
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64 #I strongly suggest 1. We also record how many junction spanning reads (JSRs) are perfect matched.
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65 if '-mm' not in args:
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66 mm=1
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67 else:
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68 i=args.index('-mm')
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69 mm=int(args[i+1])
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70
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71 #junL should be less than the read length in the dataset. I suggest it to be read_length*0.8
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72 if '-junL' not in args:
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73 sys.exit('ERROR: junL must be specified')
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74 i=args.index('-junL')
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75 overlap=int(args[i+1])
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76
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77 #minimum mapping quality for reads as fusion evidences
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78 if '-minmapq' not in args:
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79 minmapq=30
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80 else:
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81 i=args.index('-minmapq')
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82 minmapq=int(args[i+1])
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83
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84 if '-outdir' not in args:
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85 outpath=os.path.abspath('./')
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86 else:
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87 i=args.index('-outdir')
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88 outpath=os.path.abspath(args[i+1])
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89 if os.path.exists(outpath):
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90 print 'WARNING: outdir %s exists'%outpath
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91 else:
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92 os.mkdir(outpath)
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93
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94 if '-tag' not in args:
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95 docstring='prada'
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96 else:
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97 i=args.index('-tag')
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98 docstring=args[i+1]
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99
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100 #by default, search conf.txt in the prada folder
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101 prada_path=os.path.dirname(os.path.abspath(__file__)) #path to find libraries and executives.
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102 ref_search_path=[prada_path,os.getcwd()] #search path for conf file if not specified in command line
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103
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104 if '-conf' in args:
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105 i=args.index('-ref')
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106 reffile=args[i+1]
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107 if os.path.exists(reffile):
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108 pass
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109 else:
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110 for pth in ref_search_path:
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111 new_reffile='%s/%s'%(pth, os.path.basename(reffile))
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112 if os.path.exists(new_reffile):
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113 reffile=new_reffile
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114 break
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115 else:
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116 sys.exit('ERROR: conf file %s not found'%reffile)
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117 else:
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118 reffile='%s/conf.txt'%prada_path
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119 if not os.path.exists(reffile):
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120 sys.exit('ERROR: No default conf.txt found and none specified')
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121
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122 #Now print all input parameters
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123 print 'CMD: %s'%('\t'.join(args))
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124
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125 #reference files pointing to the annotation files.
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126 refdict=ioprada.read_conf(reffile)
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127 featurefile=refdict['--REF--']['feature_file']
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128 txseqfile=refdict['--REF--']['tx_seq_file']
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129 txcatfile=refdict['--REF--']['txcat_file']
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130 cdsfile=refdict['--REF--']['cds_file']
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131
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132 #underlying utilities, automatically detected
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133 #these are customized tools. update is needed.
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134 samtools='%s/tools/samtools-0.1.16/samtools'%prada_path
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135 bwa='%s/tools/bwa-0.5.7-mh/bwa'%prada_path
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136 blastn='%s/tools/blastn'%prada_path
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137
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138 ######################################################################################
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139 print 'step 0: loading gene annotations @ %s'%time.ctime()
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140 #call functions in ioprada module //
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141 txdb,genedb=ioprada.read_feature(featurefile,verbose=True)
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142 tx_primary=ioprada.read_tx_cat(txcatfile)
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143 tx_cds=ioprada.read_cds(cdsfile)
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144
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145 ######################################################################################
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146 print 'step 1: finding discordant pairs @ %s'%time.ctime()
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147
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148 #We sift through all exons of protein coding genes and get the mapping reads.
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149 #Within, we exclude low mapping quality reads and PCR duplicates. For pairs that the two ends
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150 #map to different genes, we all it a discordant pair.
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151 #This is a step for finding all possible candidate fusions.
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152
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153 samfile=pysam.Samfile(bampath,'rb')
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154
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155 read1_ab={}
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156 read2_ab={}
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157 db1={}
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158 db2={}
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159
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160 i,N=0,len(genedb)
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161 for gene in genedb:
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162 i+=1
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163 if i%200==0:
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164 print '%d/%d genes processed for discordant pairs'%(i,N)
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165 g=genedb[gene]
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166 exons=g.get_exons()
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167 for e in exons.values():
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168 for rd in samfile.fetch(e.chr,e.start-1,e.end):
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169 if rd.mapq < minmapq:
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170 continue
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171 if rd.is_duplicate:
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172 continue
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173 if rd.mate_is_unmapped: #at this point, only consider pairs
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174 continue
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175 if rd.rnext == rd.tid and rd.mpos <= g.end and rd.mpos >= g.start-1: #remove reads that fall into the same gene range
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176 continue
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177 if rd.is_read1:
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178 if read1_ab.has_key(rd.qname):
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179 read1_ab[rd.qname].add(gene)
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180 else:
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181 read1_ab[rd.qname]=set([gene])
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182 db1[rd.qname]=rd
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183 if rd.is_read2:
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184 if read2_ab.has_key(rd.qname):
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185 read2_ab[rd.qname].add(gene)
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186 else:
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187 read2_ab[rd.qname]=set([gene])
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188 db2[rd.qname]=rd
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189
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190 ##output the discordant pairs and determine the orientation of candidate fusions
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191 discordant={} #catalogue all discordant pairs, using gene pairs as keys
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192 outfile=open('%s/%s.discordant.txt'%(outpath,docstring),'w')
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193 title=['read','gene1','gene1_chr','read1_pos','read1_mm','read1_strand','read1_orient','gene2',\
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194 'gene2_chr','read2_pos','read2_mm','read2_strand','read2_orient']
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195 outfile.write('%s\n'%('\t'.join(title)))
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196 i=0
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197 for rdid in read1_ab:
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198 i+=1
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199 if i%10000==0:
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200 print '%d discordant pairs processed'%i
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201 if not read2_ab.has_key(rdid): #skip if not all ends are catalogued
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202 continue
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203 g1set=read1_ab[rdid] #consider all combinations if a read maps to multiple genes
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204 g2set=read2_ab[rdid] #consider all combinations if a read maps to multiple genes
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205 r1,r2=db1[rdid],db2[rdid]
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206 read1strd='-1' if r1.is_reverse else '1'
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207 read2strd='-1' if r2.is_reverse else '1'
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208 for g1 in g1set:
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209 for g2 in g2set:
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210 if g1==g2: #for some uncasual cases
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211 continue
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212 g1obj,g2obj=genedb[g1],genedb[g2]
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213 read1orient='F' if read1strd == g1obj.strand else 'R' #read1 --> gene1
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214 read2orient='F' if read2strd == g2obj.strand else 'R' #read2 --> gene2
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215 fkey=''
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216 if read1orient=='F' and read2orient=='R': ##scenario I, gene1-gene2
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217 fkey=g1+'_'+g2
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218 if read1orient=='R' and read2orient=='F': ##scenario II, gene2-gene1
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219 fkey=g2+'_'+g1
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220 if fkey:
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221 if discordant.has_key(fkey):
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222 discordant[fkey].update({rdid:'%s:%s'%(read1orient,read2orient)})
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223 else:
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224 discordant[fkey]={rdid:'%s:%s'%(read1orient,read2orient)}
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225 ##output
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226 nm1=str([x[1] for x in r1.tags if x[0]=='NM'][0]) #output mismatch, but does not consider it at this point
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227 nm2=str([x[1] for x in r2.tags if x[0]=='NM'][0])
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228 uvec=[rdid,g1,g1obj.chr,str(r1.pos+1),nm1,read1strd,read1orient,g2,g2obj.chr,str(r2.pos+1),nm2,read2strd,read2orient]
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229 outfile.write('%s\n'%('\t'.join(uvec)))
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230 outfile.close()
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231
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232 ##########################################################################
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233 print 'step 2: finding recurrent pairs (candidates) @ %s'%time.ctime()
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234
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235 #step 2 finds all candidates that have at least 2 discordant pairs. Meanwhile, filter out potential
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236 #read through events. read through is defined as reads with mapping position less than 1M, while meeting
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237 #the strand expectation.
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238
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239 guess=[]
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240 outfile=open('%s/%s.recurrent.txt'%(outpath,docstring),'w')
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241 title=['geneA','geneA_chr','geneB','geneB_chr','num_pairs','IDs']
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242 outfile.write('%s\n'%('\t'.join(title)))
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243 for pp in discordant:
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244 if len(discordant[pp]) < 2: #consider only "recurrent" (more than 1 pair support) cases
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245 continue
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246 gene1,gene2=pp.split('_')
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247 g1obj,g2obj=genedb[gene1],genedb[gene2]
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248 rdset=discordant[pp].keys()
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249 #filter read-through
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250 #readthrough is defined at read level, regardless of mapping genes
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251 for rd in rdset:
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252 r1,r2=db1[rd],db2[rd]
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253 read1strd='-1' if r1.is_reverse else '1'
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254 read2strd='-1' if r2.is_reverse else '1'
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255 readthrough=False
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256 if db1[rd].tid == db2[rd].tid and abs(db1[rd].pos - db2[rd].pos) <= 1000000:
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257 if discordant[pp][rd]=='F:R':
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258 if read1strd=='1' and read2strd=='-1' and db1[rd].pos < db2[rd].pos:
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259 readthrough=True
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260 if read1strd=='-1' and read2strd=='1' and db1[rd].pos > db2[rd].pos:
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261 readthrough=True
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262 if discordant[pp][rd]=='R:F':
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263 if read2strd=='1' and read1strd=='-1' and db2[rd].pos < db1[rd].pos:
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264 readthrough=True
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265 if read2strd=='-1' and read1strd=='1' and db2[rd].pos > db1[rd].pos:
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266 readthrough=True
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267 if readthrough:
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268 del discordant[pp][rd] #in-place deletion!!!! Change the discordant variable in place!
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269 if len(discordant[pp]) < 2: #skip all that have less than 2 supporting discordant read pairs after readthrough filter
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270 continue
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271 guess.append(pp)
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272 #output
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273 uvec2=[gene1,g1obj.chr,gene2,g2obj.chr,str(len(discordant[pp])),'|'.join(discordant[pp])]
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274 outfile.write('%s\n'%('\t'.join(uvec2)))
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275 outfile.close()
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276
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277 ##########################################################################
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278 print 'step 3: finding potential junction spanning reads @ %s'%time.ctime()
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279
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280 #For all candidates, find potential junction spanning reads (JSRs). A JSR is defined as a unmapped read but with the mate mapping
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281 #to either F or R partner, with high mapping quality. Since the JSR is unmapped, it is not practical to consider PCR duplicate
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282 #because they are not properly marked.
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283
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284 Fpartners=set()
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285 Rpartners=set()
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286 for pp in guess:
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287 gs=pp.split('_')
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288 Fpartners.add(gs[0])
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289 Rpartners.add(gs[1])
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290 AllPartners=Fpartners|Rpartners
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291
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292 samfile.reset()
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293 posjun={} ##catalogue all JSRs, with track of the mate mapping genes and orientation.
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294 i,N=0,len(AllPartners)
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295 for gene in AllPartners:
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296 i+=1
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297 if i%200==0:
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298 print '%d/%d genes processed for potential junc reads'%(i,N)
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299 g=genedb[gene]
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300 exons=g.get_exons().values()
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301 for e in exons:
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302 for rd in samfile.fetch(e.chr,e.start-1,e.end):
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303 if rd.mapq < minmapq:
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304 continue
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305 if not rd.mate_is_unmapped:
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306 continue
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307 readstrd='-1' if rd.is_reverse else '1'
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308 orient='F' if readstrd == g.strand else 'R' #mapping info of mate read. JSR per se is unmapped in BAM
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309 posjun[rd.qname]={'gene':gene,'orient':orient}
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310
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311 samfile.reset()
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312 outfile=open('%s/%s.pos_junc_unmapped.fastq'%(outpath,docstring),'w')
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313 i,N=0,len(posjun)
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314 for rd in samfile:
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315 if rd.mate_is_unmapped: #since the read is potential jun spanning read, all mate map to A or B
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316 continue
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317 if rd.is_unmapped:
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318 if posjun.has_key(rd.qname):
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319 i+=1
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320 if i%10000==0:
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321 print 'extracted %d/%d potential junc reads'%(i,N)
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322 rdname='%s_prada_%s_prada_%s'%(rd.qname,posjun[rd.qname]['gene'],posjun[rd.qname]['orient']) #_prada_ as split
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323 outfile.write('@%s\n'%rdname)
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324 outfile.write('%s\n'%rd.seq)
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325 outfile.write('+\n')
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326 outfile.write('%s\n'%rd.qual)
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327 outfile.close()
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328
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329 ######################################################################################
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330 print 'step 4: building junction database @ %s'%time.ctime()
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331
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332 #Make hypothetical junctions between candidate fusion partners. To improve speed, we make a big junction database comprising
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333 #exons of all candidates, instead of by candidate individually. This also gives the possibility to assess the JSR mapping ambiguity
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334 #across many junctions. It turned out very useful in filtering out false positives.
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335 #Note that in PRADA transcript sequence file, all sequences are + strand sequences. For - strand transcript, one need to
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336 #reverse complement the sequence to get the real transcript sequences.
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337
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338 seqdb={}
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339 for record in SeqIO.parse(txseqfile,'fasta'):
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340 seqdb[record.name]=record
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341
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342 outfile=open('%s/%s.junction.fasta'%(outpath,docstring),'w')
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343 i,N=0,len(guess)
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344 for pp in guess:
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345 i+=1
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346 if i%100==0:
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347 print 'building junction for %d/%d pairs'%(i,N)
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348 gene1,gene2=pp.split('_')
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349 g1obj,g2obj=genedb[gene1],genedb[gene2]
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350 eset1=g1obj.get_exons() #unique exons in gene 1
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351 eset2=g2obj.get_exons() #unique exons in gene 2
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352 #collect unique junctions
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353 juncseqdict={} #save junction sequences
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354 for e1 in eset1.values():
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355 for e2 in eset2.values():
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356 e1_jun_name='%s:%s:%s'%(gene1,e1.chr,e1.end) if e1.strand=='1' else '%s:%s:%s'%(gene1,e1.chr,e1.start)
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357 e2_jun_name='%s:%s:%s'%(gene2,e2.chr,e2.start) if e2.strand=='1' else '%s:%s:%s'%(gene2,e2.chr,e2.end)
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358 jun_name=e1_jun_name+'_'+e2_jun_name
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359 tx1,tx2=txdb[e1.transcript],txdb[e2.transcript]
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360 max_a=tx1.exon_relative_pos()[e1.name][1]
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361 min_a=0 if max_a - overlap < 0 else max_a - overlap
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362 min_b=tx2.exon_relative_pos()[e2.name][0]-1
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363 max_b=tx2.length if min_b + overlap > tx2.length else min_b + overlap
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364 #reverse complementary when necessary
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365 try:
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366 tx1seq=seqdb[tx1.name].seq.tostring() if tx1.strand=='1' else seqdb[tx1.name].reverse_complement().seq.tostring()
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367 tx2seq=seqdb[tx2.name].seq.tostring() if tx2.strand=='1' else seqdb[tx2.name].reverse_complement().seq.tostring()
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368 except KeyError: #in case transcript not found in sequence file
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369 continue
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370 jun_seq=tx1seq[min_a:max_a]+tx2seq[min_b:max_b]
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371 juncseqdict[jun_name]=jun_seq
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372 for junc in juncseqdict:
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373 outfile.write('>%s\n'%junc)
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374 outfile.write('%s\n'%juncseqdict[junc])
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375 outfile.close()
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376 samfile.close()
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377
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378 #for memory efficiecy, del seqdb
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379 del seqdb
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380
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381 ########################################################################################
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382 print 'step 5: aligning potential junction reads to junction database @ %s'%time.ctime()
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383
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384 #Mapping potential JSRs to hypothetical junction database.
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385 #Allow 4 mismatches at the beginning.
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386
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387 idx_cmd='%s index %s/%s.junction.fasta'%(bwa,outpath,docstring)
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388 os.system(idx_cmd)
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389 aln_cmd='%s aln -n 4 -R 100 %s/%s.junction.fasta %s/%s.pos_junc_unmapped.fastq > %s/%s.juncmap.sai'%(bwa,outpath,docstring,outpath,docstring,outpath,docstring)
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390 os.system(aln_cmd)
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391 samse_cmd='%s samse -n 1000 -s %s/%s.junction.fasta %s/%s.juncmap.sai %s/%s.pos_junc_unmapped.fastq > %s/%s.juncmap.sam'%(bwa,outpath,docstring,outpath,docstring,outpath,docstring,outpath,docstring)
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392 os.system(samse_cmd)
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393 sam2bam_cmd='%s view -bS %s/%s.juncmap.sam -o %s/%s.juncmap.bam'%(samtools,outpath,docstring,outpath,docstring)
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394 os.system(sam2bam_cmd)
|
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395
|
|
396 jsam=pysam.Samfile('%s/%s.juncmap.bam'%(outpath,docstring),'rb')
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397 #get the junction name directory
|
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398 junctions=jsam.references
|
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399 junname=dict(zip(range(0,len(junctions)),junctions)) #this is essential for quick speed.
|
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400 junc_align={}
|
|
401
|
|
402 #go through the BAM file for meaningful (meeting fusion orientation etc) reads
|
|
403 strd_right_reads={}
|
|
404 rdb={} #collect all junction spanning reads
|
|
405 i=0
|
|
406 for rd in jsam:
|
|
407 i+=1
|
|
408 if i%100000==0:
|
|
409 print '%d junction alignments parsed'%i
|
|
410 if rd.is_unmapped:
|
|
411 continue
|
|
412 read,mate_gene,mate_orient=rd.qname.split('_prada_')
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|
413 junc=junname[rd.tid]
|
|
414 tmp=junc.split('_')
|
|
415 gene1,gene2=[x.split(':')[0] for x in tmp]
|
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416 if gene1==mate_gene:
|
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417 if mate_orient=='F':
|
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418 if rd.is_reverse:
|
|
419 if strd_right_reads.has_key(rd.qname):
|
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420 strd_right_reads[rd.qname]+=1 #count how many times the read maps
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421 else:
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422 strd_right_reads[rd.qname]=1
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|
423 rdb[rd.qname]={'read':rd,'gene1':gene1,'gene2':gene2,'junc':junc} #will overwrite, but it is OK since we only look at unique ones
|
|
424 elif gene2==mate_gene:
|
|
425 if mate_orient == 'R':
|
|
426 if not rd.is_reverse:
|
|
427 if strd_right_reads.has_key(rd.qname):
|
|
428 strd_right_reads[rd.qname]+=1
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429 else:
|
|
430 strd_right_reads[rd.qname]=1
|
|
431 rdb[rd.qname]={'read':rd,'gene1':gene1,'gene2':gene2,'junc':junc} #will overwrite, but it is OK since we only look at unique ones
|
|
432
|
|
433 #find uniquely mapped reads and their gene pairs
|
|
434 junc_map={} #a dictionary from junction to mapping reads
|
|
435 for rdname in strd_right_reads:
|
|
436 if strd_right_reads[rdname] > 1: #remove non-unique junction spanning reads
|
|
437 continue
|
|
438 infodict=rdb[rdname]
|
|
439 pp=infodict['gene1']+'_'+infodict['gene2']
|
|
440 if junc_map.has_key(pp):
|
|
441 junc_map[pp].add(rdname)
|
|
442 else:
|
|
443 junc_map[pp]=set([rdname])
|
|
444
|
|
445 ########################################################################################
|
|
446 print 'step 6: summarizing fusion evidences @ %s'%time.ctime()
|
|
447
|
|
448 #Now, time to apply mismatch filter and summarize the results
|
|
449 #Candidate fusions --> guess
|
|
450 #Discordant pairs --> discordant, db1, db2
|
|
451 #Junction reads --> junc_map, rdb
|
|
452 #Gene info --> genedb
|
|
453
|
|
454 outfile_s=open('%s/%s.fus.candidates.txt'%(outpath,docstring),'w')
|
|
455 outfile_d=open('%s/%s.fus.evidences.txt'%(outpath,docstring),'w')
|
|
456
|
|
457 title=['Gene_A','Gene_B','A_chr','B_chr','A_strand','B_strand','Discordant_n','JSR_n','perfectJSR_n','Junc_n','Position_Consist','Junction']
|
|
458 outfile_s.write('%s\n'%('\t'.join(title)))
|
|
459
|
|
460 for pp in junc_map: #all pairs with junc reads
|
|
461 gene1,gene2=pp.split('_')
|
|
462 g1obj,g2obj=genedb[gene1],genedb[gene2]
|
|
463 fus_disc=[] #collecting discordant pairs
|
|
464 for rdname in discordant[pp]:
|
|
465 #arrange read1/read2 into F/R so it will be easier for GeneFusion obj to handle
|
|
466 r1,r2=db1[rdname],db2[rdname]
|
|
467 orient=discordant[pp][rdname]
|
|
468 if orient=='F:R':
|
|
469 fus_disc.append((r1,r2))
|
|
470 elif orient=='R:F':
|
|
471 fus_disc.append((r2,r1))
|
|
472 fus_jsr=[]
|
|
473 if junc_map.has_key(pp):
|
|
474 for rdname in junc_map[pp]:
|
|
475 r=rdb[rdname]['read']
|
|
476 junc=rdb[rdname]['junc']
|
|
477 jsr=gfclass.JSR(r,junc)
|
|
478 fus_jsr.append(jsr)
|
|
479 gf=gfclass.GeneFusion(gene1,gene2,fus_disc,fus_jsr)
|
|
480 gf_new=gf.update(mm=mm) ##apply the mismatch parameter, default is 1
|
|
481 #output the results
|
|
482 disc_n=str(len(gf_new.discordantpairs))
|
|
483 junctions=sorted(gf_new.get_junction_freq(),key=operator.itemgetter(1),reverse=True) #sort junc by # of JSRs
|
|
484 junc_n=str(len(junctions))
|
|
485 junc_str='|'.join([','.join([x[0],str(x[1])]) for x in junctions])
|
|
486 jsr_n=str(len(gf_new.fusionreads))
|
|
487 pjsr_n=str(len(gf_new.get_perfect_JSR()))
|
|
488 pos_consist=gf_new.positioncheck()
|
|
489 svec=[gene1,gene2,g1obj.chr,g2obj.chr,g1obj.strand,g2obj.strand,disc_n,jsr_n,pjsr_n,junc_n,pos_consist,junc_str]
|
|
490 outfile_s.write('%s\n'%('\t'.join(svec)))
|
|
491 outfile_d.write('@@\t%s,%s,%s\t%s,%s,%s\n'%(gene1,g1obj.chr,g1obj.strand,gene2,g2obj.chr,g2obj.strand))
|
|
492 outfile_d.write('\n')
|
|
493 outfile_d.write('>discordant\n')
|
|
494 for rp in gf_new.discordantpairs:
|
|
495 rf,rr=rp
|
|
496 nm1=[x[1] for x in rf.tags if x[0]=='NM'][0]
|
|
497 nm2=[x[1] for x in rr.tags if x[0]=='NM'][0]
|
|
498 outfile_d.write('%s\tF\t%s.%s.mm%d\n'%(rf.qname,gene1,rf.pos+1,nm1)) ##0-based coordinates
|
|
499 outfile_d.write('%s\tR\t%s.%s.mm%d\n'%(rr.qname,gene2,rr.pos+1,nm2)) ##0-based coordinates
|
|
500 outfile_d.write('\n')
|
|
501 outfile_d.write('>spanning\n')
|
|
502 for jsr in gf_new.fusionreads:
|
|
503 r=jsr.read
|
|
504 nm=[x[1] for x in r.tags if x[0]=='NM'][0]
|
|
505 outfile_d.write('%s\t%s.mm%d\n'%(r.qname,jsr.junction,nm))
|
|
506 outfile_d.write('\n')
|
|
507 outfile_d.write('>junction\n')
|
|
508 for junc_info in junctions:
|
|
509 outfile_d.write('%s\t%d\n'%(junc_info[0],junc_info[1]))
|
|
510 outfile_d.write('\n')
|
|
511 outfile_d.write('>summary\n')
|
|
512 outfile_d.write('Number of Discordant Pairs = %s\n'%disc_n)
|
|
513 outfile_d.write('Number of Fusion Reads = %s\n'%jsr_n)
|
|
514 outfile_d.write('Number of Perfect Fusion Reads = %s\n'%pjsr_n)
|
|
515 outfile_d.write('Number of Distinct Junctions = %s\n'%junc_n)
|
|
516 outfile_d.write('Position Consistency = %s\n'%pos_consist)
|
|
517 outfile_d.write('\n')
|
|
518
|
|
519 outfile_s.close()
|
|
520 outfile_d.close()
|
|
521
|
|
522 ########################################################################################
|
|
523 print 'step 7: generating fusion lists @ %s'%time.ctime()
|
|
524
|
|
525 #For convenience, filter the lists to candidates with
|
|
526 # 1) at least 2 discordant pairs
|
|
527 # 2) at least 1 perfect JSR
|
|
528 #meanwhile, calculate sequence similarity for each pair
|
|
529 #user may need to manually filter the lists per this measure.
|
|
530
|
|
531 #The following code is a copy of prada-homology
|
|
532 outfile_o=open('%s/%s.fus.summary.txt'%(outpath,docstring),'w')
|
|
533 ifname='%s/%s.fus.candidates.txt'%(outpath,docstring)
|
|
534 if not os.path.exists(ifname):
|
|
535 sys.exit('ERROR: %s was not found'%ifname)
|
|
536
|
|
537 blastseq_tmp_dir='%s/blast_tmp/'%outpath
|
|
538 if not os.path.exists(blastseq_tmp_dir):
|
|
539 os.mkdir(blastseq_tmp_dir)
|
|
540
|
|
541 flists=[]
|
|
542 infile=open(ifname)
|
|
543 iN=0
|
|
544 for line in open(ifname):
|
|
545 info=line.strip().split('\t')
|
|
546 if iN==0:
|
|
547 iN+=1 #skip title
|
|
548 flists.append(info)
|
|
549 continue
|
|
550 else:
|
|
551 if int(info[6])>=2 and int(info[8])>=1 and info[10] in ['PARTIALLY','YES']:
|
|
552 flists.append(info)
|
|
553 infile.close()
|
|
554
|
|
555 if len(flists)==1: #if no candidate passes the filters
|
|
556 outfile_o.write('%s\n'%'\t'.join(flists[0]))
|
|
557 outfile_o.close()
|
|
558 print 'step done @ %s'%time.ctime()
|
|
559 sys.exit(0)
|
|
560
|
|
561 candidates={}
|
|
562 for line in flists[1:]:
|
|
563 geneA,geneB=line[0],line[1]
|
|
564 key='%s_%s'%(geneA,geneB)
|
|
565 candidates[key]=''
|
|
566
|
|
567 selecttranscript={}
|
|
568 for gene in genedb:
|
|
569 txs=genedb[gene].transcript
|
|
570 stx=txs[0]
|
|
571 initlen=stx.length
|
|
572 for tx in txs:
|
|
573 if tx.length >= initlen:
|
|
574 stx=tx
|
|
575 initlen=stx.length
|
|
576 selecttranscript[gene]=stx.name
|
|
577
|
|
578 allpartners=set()
|
|
579 for item in candidates:
|
|
580 sset=set(item.split('_'))
|
|
581 allpartners=allpartners.union(sset)
|
|
582
|
|
583 presenttxs=[] #tx that is present in our annotation
|
|
584 absent=[] #tx that is not in our annotation
|
|
585 for gene in allpartners:
|
|
586 if selecttranscript.has_key(gene):
|
|
587 presenttxs.append(selecttranscript[gene])
|
|
588 else:
|
|
589 absent.append(gene)
|
|
590
|
|
591 for seq_record in SeqIO.parse(txseqfile,'fasta'):
|
|
592 sid=seq_record.id
|
|
593 seq=seq_record.seq
|
|
594 if sid in presenttxs:
|
|
595 g=txdb[sid].gene
|
|
596 fastafile=open('%s/%s.fasta'%(blastseq_tmp_dir,g),'w')
|
|
597 SeqIO.write(seq_record,fastafile,'fasta')
|
|
598 fastafile.close()
|
|
599
|
|
600 for gp in candidates:
|
|
601 geneA,geneB=gp.split('_')
|
|
602 if geneA in absent or geneB in absent:
|
|
603 candidates[gp]=['NA']*4
|
|
604 else:
|
|
605 gaseq='%s/%s.fasta'%(blastseq_tmp_dir,geneA)
|
|
606 gaobj=SeqIO.parse(gaseq,'fasta').next()
|
|
607 gbseq='%s/%s.fasta'%(blastseq_tmp_dir,geneB)
|
|
608 gbobj=SeqIO.parse(gbseq,'fasta').next()
|
|
609 ga_len,gb_len=str(len(gaobj.seq)),str(len(gbobj.seq))
|
|
610 a=privutils.seqblast(gaseq,gbseq,blastn)
|
|
611 if a==None:
|
|
612 candidates[gp]=['NA','NA','100','0']
|
|
613 else:
|
|
614 candidates[gp]=a
|
|
615
|
|
616 header=flists[0][:]
|
|
617 header.extend(['Identity','Align_Len','Evalue','BitScore'])
|
|
618 outfile_o.write('%s\n'%('\t'.join(header)))
|
|
619
|
|
620 for info in flists[1:]:
|
|
621 geneA,geneB=info[0],info[1]
|
|
622 key='%s_%s'%(geneA,geneB)
|
|
623 vv=candidates[key]
|
|
624 row=info[:]
|
|
625 row.extend(vv)
|
|
626 outfile_o.write('%s\n'%('\t'.join(row)))
|
|
627 outfile_o.close()
|
|
628
|
|
629 ########################################################################################
|
|
630 print 'step done @ %s'%time.ctime()
|