def check_fastq_files(fastq_files, segment_length, trim5, trim3):
# check that input fastq files exist
read_lengths = []
for mate,fastq_file in enumerate(fastq_files):
if not os.path.isfile(fastq_file):
raise AlignError("mate '%d' fastq file '%s' is not valid" %
(mate, fastq_file))
logging.debug("Checking read length for file %s" % (fastq_file))
read_lengths.append(get_read_length(fastq_file))
logging.debug("Read length for file %s: %d" %
(fastq_file, read_lengths[-1]))
# check that mate read lengths are equal
if len(set(read_lengths)) > 1:
logging.error("read lengths mate1=%d and mate2=%d are unequal" %
(read_lengths[0], read_lengths[1]))
return False
rlen = read_lengths[0]
trimmed_rlen = rlen - trim5 - trim3
# check that segment length >= MIN_SEGMENT_LENGTH
if segment_length < MIN_SEGMENT_LENGTH:
raise AlignError("segment length (%d) too small (min is %d)" %
(segment_length, MIN_SEGMENT_LENGTH))
# check that segment length < trimmed read length
if segment_length > trimmed_rlen:
raise AlignError("segment length (%d) longer than trimmed read length (%d)" %
(segment_length, trimmed_rlen))
return read_lengths[0]
def check_command_line_args(options, args, parser):
# check command line arguments
if len(args) < 3:
parser.error("Incorrect number of command line arguments")
fastq_files = args[0:2]
output_dir = args[2]
# check that input fastq files exist
read_lengths = []
for mate, fastq_file in enumerate(fastq_files):
if not os.path.isfile(args[0]):
parser.error("mate '%d' fastq file '%s' is not valid" %
(mate, fastq_file))
logging.debug("Checking read length for file %s" % (fastq_file))
read_lengths.append(get_read_length(fastq_file))
logging.debug("Read length for file %s: %d" %
(fastq_file, read_lengths[-1]))
# check that mate read lengths are equal
if len(set(read_lengths)) > 1:
parser.error("read lengths mate1=%d and mate2=%d are unequal" %
(read_lengths[0], read_lengths[1]))
# check that seed length < read length
if any(options.segment_length > rlen for rlen in read_lengths):
parser.error("seed length %d cannot be longer than read length" %
(options.segment_length))
# check that output dir is not a regular file
if os.path.exists(output_dir) and (not os.path.isdir(output_dir)):
parser.error(
"Output directory name '%s' exists and is not a valid directory" %
(output_dir))
if check_executable(options.bowtie_build_bin):
logging.debug("Checking for 'bowtie-build' binary... found")
else:
parser.error("bowtie-build binary not found or not executable")
# check that bowtie program exists
if check_executable(options.bowtie_bin):
logging.debug("Checking for 'bowtie' binary... found")
else:
parser.error("bowtie binary not found or not executable")
# check that alignment index exists
if os.path.isdir(options.index_dir):
logging.debug("Checking for chimerascan index directory... found")
else:
parser.error("chimerascan alignment index directory '%s' not valid" %
(options.index_dir))
# check that alignment index file exists
align_index_file = os.path.join(options.index_dir,
config.BOWTIE_INDEX_FILE)
if os.path.isfile(align_index_file):
logging.debug("Checking for bowtie index file... found")
else:
parser.error("chimerascan bowtie index file '%s' invalid" %
(align_index_file))
# check for sufficient processors
if options.num_processors < config.BASE_PROCESSORS:
logging.warning(
"Please specify >=2 processes using '-p' to allow program to run efficiently"
)
def check_config(self):
# check that input fastq files exist
config_passed = True
read_lengths = []
for mate,fastq_file in enumerate(self.fastq_files):
if not os.path.isfile(fastq_file):
logging.error("mate '%d' fastq file '%s' is not valid" %
(mate, fastq_file))
config_passed = False
read_lengths.append(get_read_length(fastq_file))
logging.debug("Checking file %s" % (fastq_file))
logging.debug("File %s read length=%d" % (fastq_file, read_lengths[-1]))
# check that mate read lengths are equal
if len(set(read_lengths)) > 1:
logging.error("Unequal read lengths mate1=%d and mate2=%d" %
(read_lengths[0], read_lengths[1]))
config_passed = False
# check that seed length < read length
if any(self.segment_length > rlen for rlen in read_lengths):
logging.error("seed length %d cannot be longer than read length" %
(self.segment_length))
config_passed = False
# check that output dir is not a regular file
if os.path.exists(self.output_dir) and (not os.path.isdir(self.output_dir)):
logging.error("Output directory name '%s' exists and is not a valid directory" %
(self.output_dir))
config_passed = False
if check_executable(self.bowtie_build_bin):
logging.debug("Checking for 'bowtie-build' binary... found")
else:
logging.error("bowtie-build binary not found or not executable")
config_passed = False
# check that bowtie program exists
if check_executable(self.bowtie_bin):
logging.debug("Checking for 'bowtie' binary... found")
else:
logging.error("bowtie binary not found or not executable")
config_passed = False
# check that alignment index exists
if os.path.isdir(self.index_dir):
logging.debug("Checking for chimerascan index directory... found")
# check that alignment index file exists
align_index_file = os.path.join(self.index_dir, config.BOWTIE_INDEX_FILE)
if os.path.isfile(align_index_file):
logging.debug("Checking for bowtie index file... found")
else:
logging.error("chimerascan bowtie index file '%s' invalid" % (align_index_file))
config_passed = False
else:
logging.error("chimerascan alignment index directory '%s' not valid" %
(self.index_dir))
config_passed = False
# check for sufficient processors
if self.num_processors < config.BASE_PROCESSORS:
logging.warning("Please specify >=2 processes using '-p' to allow program to run efficiently")
return config_passed
def align_pe_full(fastq_files,
bowtie_index,
output_bam_file,
unaligned_fastq_param,
maxmultimap_fastq_param,
min_fragment_length=0,
max_fragment_length=1000,
trim5=0,
trim3=0,
library_type="fr",
num_processors=1,
fastq_format="phred33-quals",
multihits=100,
mismatches=2,
bowtie_bin="bowtie",
bowtie_mode="-n",
log_file=None):
read_length = get_read_length(fastq_files[0])
args = [bowtie_bin, "-q", "-S",
"-p", str(num_processors),
"--%s" % fastq_format,
"-k", str(multihits),
"-m", str(multihits),
bowtie_mode, str(mismatches),
"--minins", min_fragment_length,
"--maxins", max_fragment_length,
"--trim5", trim5,
"--trim3", trim3,
"--%s" % library_type,
"--un", unaligned_fastq_param,
"--max", maxmultimap_fastq_param]
# use the entire read length as the "seed" here
if bowtie_mode == "-n":
args.extend(["-l", str(read_length)])
args += [bowtie_index,
"-1", fastq_files[0],
"-2", fastq_files[1]]
#aligned_sam_file]
args = map(str, args)
logging.debug("Bowtie alignment args: %s" % (' '.join(args)))
aln_p = subprocess.Popen(args, stdout=subprocess.PIPE)
# pipe the bowtie SAM output to a filter that writes BAM format
args = [sys.executable, __file__, "--multihits", str(multihits),
output_bam_file, fastq_files[0]]
logging.debug("SAM to BAM converter args: %s" % (' '.join(args)))
if log_file is not None:
logfh = open(log_file, "w")
else:
logfh = None
retcode = subprocess.call(args, stdin=aln_p.stdout, stderr=logfh)
if logfh is not None:
logfh.close()
if retcode != 0:
return retcode
return aln_p.wait()
def align_pe_full(fastq_files,
bowtie_index,
output_bam_file,
unaligned_fastq_param,
maxmultimap_fastq_param,
min_fragment_length=0,
max_fragment_length=1000,
trim5=0,
trim3=0,
library_type="fr",
num_processors=1,
fastq_format="phred33-quals",
multihits=100,
mismatches=2,
bowtie_bin="bowtie",
bowtie_mode="-n",
log_file=None):
read_length = get_read_length(fastq_files[0])
args = [
bowtie_bin, "-q", "-S", "-p",
str(num_processors),
"--%s" % fastq_format, "-k",
str(multihits), "-m",
str(multihits), bowtie_mode,
str(mismatches), "--minins", min_fragment_length, "--maxins",
max_fragment_length, "--trim5", trim5, "--trim3", trim3,
"--%s" % library_type, "--un", unaligned_fastq_param, "--max",
maxmultimap_fastq_param
]
# use the entire read length as the "seed" here
if bowtie_mode == "-n":
args.extend(["-l", str(read_length)])
args += [bowtie_index, "-1", fastq_files[0], "-2", fastq_files[1]]
#aligned_sam_file]
args = map(str, args)
logging.debug("Bowtie alignment args: %s" % (' '.join(args)))
aln_p = subprocess.Popen(args, stdout=subprocess.PIPE)
# pipe the bowtie SAM output to a filter that writes BAM format
args = [
sys.executable, __file__, "--multihits",
str(multihits), output_bam_file, fastq_files[0]
]
logging.debug("SAM to BAM converter args: %s" % (' '.join(args)))
if log_file is not None:
logfh = open(log_file, "w")
else:
logfh = None
retcode = subprocess.call(args, stdin=aln_p.stdout, stderr=logfh)
if logfh is not None:
logfh.close()
if retcode != 0:
return retcode
return aln_p.wait()
def check_command_line_args(options, args, parser):
# check command line arguments
if len(args) < 3:
parser.error("Incorrect number of command line arguments")
fastq_files = args[0:2]
output_dir = args[2]
# check that input fastq files exist
read_lengths = []
for mate,fastq_file in enumerate(fastq_files):
if not os.path.isfile(args[0]):
parser.error("mate '%d' fastq file '%s' is not valid" %
(mate, fastq_file))
logging.debug("Checking read length for file %s" %
(fastq_file))
read_lengths.append(get_read_length(fastq_file))
logging.debug("Read length for file %s: %d" %
(fastq_file, read_lengths[-1]))
# check that mate read lengths are equal
if len(set(read_lengths)) > 1:
parser.error("read lengths mate1=%d and mate2=%d are unequal" %
(read_lengths[0], read_lengths[1]))
# check that seed length < read length
if any(options.segment_length > rlen for rlen in read_lengths):
parser.error("seed length %d cannot be longer than read length" %
(options.segment_length))
# check that output dir is not a regular file
if os.path.exists(output_dir) and (not os.path.isdir(output_dir)):
parser.error("Output directory name '%s' exists and is not a valid directory" %
(output_dir))
if check_executable(options.bowtie_build_bin):
logging.debug("Checking for 'bowtie-build' binary... found")
else:
parser.error("bowtie-build binary not found or not executable")
# check that bowtie program exists
if check_executable(options.bowtie_bin):
logging.debug("Checking for 'bowtie' binary... found")
else:
parser.error("bowtie binary not found or not executable")
# check that alignment index exists
if os.path.isdir(options.index_dir):
logging.debug("Checking for chimerascan index directory... found")
else:
parser.error("chimerascan alignment index directory '%s' not valid" %
(options.index_dir))
# check that alignment index file exists
align_index_file = os.path.join(options.index_dir, config.BOWTIE_INDEX_FILE)
if os.path.isfile(align_index_file):
logging.debug("Checking for bowtie index file... found")
else:
parser.error("chimerascan bowtie index file '%s' invalid" % (align_index_file))
# check for sufficient processors
if options.num_processors < config.BASE_PROCESSORS:
logging.warning("Please specify >=2 processes using '-p' to allow program to run efficiently")
def run_chimerascan(runconfig):
# normal run
config_passed = runconfig.check_config()
if not config_passed:
logging.error("Invalid run configuration, aborting.")
sys.exit(JOB_ERROR)
# create output dir if it does not exist
if not os.path.exists(runconfig.output_dir):
os.makedirs(runconfig.output_dir)
logging.info("Created output directory: %s" % (runconfig.output_dir))
# create log dir if it does not exist
log_dir = os.path.join(runconfig.output_dir, config.LOG_DIR)
if not os.path.exists(log_dir):
os.makedirs(log_dir)
logging.debug("Created directory for log files: %s" % (log_dir))
# create tmp dir if it does not exist
tmp_dir = os.path.join(runconfig.output_dir, config.TMP_DIR)
if not os.path.exists(tmp_dir):
os.makedirs(tmp_dir)
logging.debug("Created directory for tmp files: %s" % (tmp_dir))
# write the run config to a file
xmlstring = runconfig.to_xml()
runconfig_xml_file = os.path.join(runconfig.output_dir,
config.RUNCONFIG_XML_FILE)
fh = open(runconfig_xml_file, "w")
print >> fh, xmlstring
fh.close()
# gather and parse run parameters
library_type = parse_library_type(runconfig.library_type)
gene_feature_file = os.path.join(runconfig.index_dir,
config.GENE_FEATURE_FILE)
bowtie_mode = "-v" if runconfig.bowtie_mode_v else "-n"
bowtie_index = os.path.join(runconfig.index_dir, config.ALIGN_INDEX)
original_read_length = get_read_length(runconfig.fastq_files[0])
# minimum fragment length cannot be smaller than the trimmed read length
trimmed_read_length = original_read_length - runconfig.trim5 - runconfig.trim3
min_fragment_length = max(runconfig.min_fragment_length,
trimmed_read_length)
#
# Initial Bowtie alignment step
#
# align in paired-end mode, trying to resolve as many reads as possible
# this effectively rules out the vast majority of reads as candidate
# fusions
unaligned_fastq_param = os.path.join(tmp_dir, config.UNALIGNED_FASTQ_PARAM)
maxmultimap_fastq_param = os.path.join(tmp_dir,
config.MAXMULTIMAP_FASTQ_PARAM)
aligned_bam_file = os.path.join(runconfig.output_dir,
config.ALIGNED_READS_BAM_FILE)
aligned_log_file = os.path.join(log_dir, "bowtie_alignment.log")
if all(up_to_date(aligned_bam_file, fq) for fq in runconfig.fastq_files):
logging.info("[SKIPPED] Alignment results exist")
else:
logging.info("Aligning full-length reads in paired-end mode")
retcode = align_pe_full(
runconfig.fastq_files,
bowtie_index,
aligned_bam_file,
unaligned_fastq_param,
maxmultimap_fastq_param,
min_fragment_length=min_fragment_length,
max_fragment_length=runconfig.max_fragment_length,
trim5=runconfig.trim5,
trim3=runconfig.trim3,
library_type=runconfig.library_type,
num_processors=runconfig.num_processors,
fastq_format=runconfig.fastq_format,
multihits=runconfig.multihits,
mismatches=runconfig.mismatches,
bowtie_bin=runconfig.bowtie_bin,
bowtie_mode=bowtie_mode,
log_file=aligned_log_file)
if retcode != 0:
logging.error("Bowtie failed with error code %d" % (retcode))
sys.exit(retcode)
#
# Get insert size distribution
#
isize_dist_file = os.path.join(runconfig.output_dir,
config.ISIZE_DIST_FILE)
isize_dist = InsertSizeDistribution()
if up_to_date(isize_dist_file, aligned_bam_file):
logging.info("[SKIPPED] Profiling insert size distribution")
isize_dist.from_file(open(isize_dist_file, "r"))
else:
logging.info("Profiling insert size distribution")
max_isize_samples = config.ISIZE_MAX_SAMPLES
bamfh = pysam.Samfile(aligned_bam_file, "rb")
isize_dist.from_bam(bamfh,
min_isize=min_fragment_length,
max_isize=runconfig.max_fragment_length,
max_samples=max_isize_samples)
isize_dist.to_file(open(isize_dist_file, "w"))
bamfh.close()
logging.info("Insert size samples=%d mean=%f std=%f median=%d mode=%d" %
(isize_dist.n, isize_dist.mean(), isize_dist.std(),
isize_dist.percentile(50.0), isize_dist.mode()))
#
# Discordant reads alignment step
#
discordant_bam_file = os.path.join(tmp_dir, config.DISCORDANT_BAM_FILE)
discordant_log_file = os.path.join(log_dir,
"bowtie_segmented_alignment.log")
unaligned_fastq_files = [
os.path.join(tmp_dir, fq) for fq in config.UNALIGNED_FASTQ_FILES
]
# get the segments used in discordant alignment to know the effective
# read length used to align. we used this to set the 'padding' during
# spanning read discovery
segments = determine_read_segments(original_read_length,
segment_length=runconfig.segment_length,
segment_trim=True,
trim5=runconfig.trim5,
trim3=runconfig.trim3)
segmented_read_length = segments[-1][1]
logging.debug("Segmented alignment will use effective read length of %d" %
(segmented_read_length))
if all(
up_to_date(discordant_bam_file, fq)
for fq in runconfig.fastq_files):
logging.info("[SKIPPED] Discordant alignment results exist")
else:
logging.info("Aligning initially unmapped reads in single read mode")
align(unaligned_fastq_files,
runconfig.fastq_format,
bowtie_index,
discordant_bam_file,
bowtie_bin=runconfig.bowtie_bin,
num_processors=runconfig.num_processors,
segment_length=runconfig.segment_length,
segment_trim=True,
trim5=runconfig.trim5,
trim3=runconfig.trim3,
multihits=runconfig.multihits,
mismatches=runconfig.mismatches,
bowtie_mode=bowtie_mode,
best_strata=runconfig.best_strata,
log_file=discordant_log_file)
#
# Merge paired-end reads step
#
paired_bam_file = os.path.join(tmp_dir, config.DISCORDANT_PAIRED_BAM_FILE)
if up_to_date(paired_bam_file, discordant_bam_file):
logging.info("[SKIPPED] Read pairing results exist")
else:
logging.info("Pairing aligned reads")
bamfh = pysam.Samfile(discordant_bam_file, "rb")
paired_bamfh = pysam.Samfile(paired_bam_file, "wb", template=bamfh)
merge_read_pairs(bamfh, paired_bamfh, runconfig.min_fragment_length,
runconfig.max_fragment_length, library_type)
paired_bamfh.close()
bamfh.close()
#
# Find discordant reads step
#
discordant_gene_bedpe_file = \
os.path.join(tmp_dir, config.DISCORDANT_GENE_BEDPE_FILE)
discordant_genome_bedpe_file = \
os.path.join(tmp_dir, config.DISCORDANT_GENOME_BEDPE_FILE)
padding = original_read_length - segmented_read_length
if (up_to_date(discordant_gene_bedpe_file, paired_bam_file)
and up_to_date(discordant_genome_bedpe_file, paired_bam_file)):
logging.info("[SKIPPED] Finding discordant reads")
else:
logging.info("Finding discordant reads")
bamfh = pysam.Samfile(paired_bam_file, "rb")
find_discordant_reads(bamfh,
discordant_gene_bedpe_file,
discordant_genome_bedpe_file,
gene_feature_file,
max_indel_size=runconfig.max_indel_size,
max_isize=runconfig.max_fragment_length,
max_multihits=runconfig.multihits,
library_type=library_type,
padding=padding)
bamfh.close()
#
# Extract full sequences of the discordant reads
#
extended_discordant_gene_bedpe_file = \
os.path.join(tmp_dir,
config.EXTENDED_DISCORDANT_GENE_BEDPE_FILE)
if up_to_date(extended_discordant_gene_bedpe_file,
discordant_gene_bedpe_file):
logging.info(
"[SKIPPED] Retrieving full length sequences for realignment")
else:
logging.info("Retrieving full length sequences for realignment")
extend_sequences(unaligned_fastq_files, discordant_gene_bedpe_file,
extended_discordant_gene_bedpe_file)
#
# Sort discordant reads
#
sorted_discordant_gene_bedpe_file = os.path.join(
tmp_dir, config.SORTED_DISCORDANT_GENE_BEDPE_FILE)
if (up_to_date(sorted_discordant_gene_bedpe_file,
extended_discordant_gene_bedpe_file)):
logging.info("[SKIPPED] Sorting discordant BEDPE file")
else:
logging.info("Sorting discordant BEDPE file")
sort_discordant_reads(extended_discordant_gene_bedpe_file,
sorted_discordant_gene_bedpe_file)
#
# Nominate chimeras step
#
encompassing_bedpe_file = os.path.join(
tmp_dir, config.ENCOMPASSING_CHIMERA_BEDPE_FILE)
if (up_to_date(encompassing_bedpe_file,
sorted_discordant_gene_bedpe_file)):
logging.info("[SKIPPED] Nominating chimeras from discordant reads")
else:
logging.info("Nominating chimeras from discordant reads")
nominate_chimeras(open(sorted_discordant_gene_bedpe_file, "r"),
open(encompassing_bedpe_file, "w"),
gene_feature_file,
trim=config.EXON_JUNCTION_TRIM_BP)
#
# Filter encompassing chimeras step
#
filtered_encomp_bedpe_file = \
os.path.join(tmp_dir,
config.FILTERED_ENCOMPASSING_CHIMERA_BEDPE_FILE)
if (up_to_date(filtered_encomp_bedpe_file, encompassing_bedpe_file)):
logging.info("[SKIPPED] Filtering encompassing chimeras")
else:
logging.info("Filtering encompassing chimeras")
# max_isize = isize_mean + runconfig.filter_isize_stdevs*isize_std
filter_encompassing_chimeras(
encompassing_bedpe_file,
filtered_encomp_bedpe_file,
gene_feature_file,
max_multimap=runconfig.filter_max_multimaps,
multimap_cov_ratio=runconfig.filter_multimap_ratio,
max_isize=-1,
strand_pval=runconfig.filter_strand_pval)
#
# Nominate spanning reads step
#
spanning_fastq_file = os.path.join(runconfig.output_dir,
config.SPANNING_FASTQ_FILE)
if all(up_to_date(spanning_fastq_file, f) for f in unaligned_fastq_files):
logging.info("[SKIPPED] Preparing junction spanning reads")
else:
logging.info("Preparing junction spanning reads")
outfh = open(spanning_fastq_file, "w")
for f in unaligned_fastq_files:
shutil.copyfileobj(open(f), outfh)
outfh.close()
# TODO: skip this step for now, and simply realign all the reads
# spanning_fastq_file = os.path.join(runconfig.output_dir, config.SPANNING_FASTQ_FILE)
# if (up_to_date(spanning_fastq_file, extended_discordant_bedpe_file) and
# up_to_date(spanning_fastq_file, filtered_encomp_bedpe_file)):
# logging.info("[SKIPPED] Nominating junction spanning reads")
# else:
# logging.info("Nominating junction spanning reads")
# nominate_spanning_reads(open(extended_discordant_bedpe_file, 'r'),
# open(filtered_encomp_bedpe_file, 'r'),
# open(spanning_fastq_file, 'w'))
#
# Extract junction sequences from chimeras file
#
ref_fasta_file = os.path.join(runconfig.index_dir,
config.ALIGN_INDEX + ".fa")
junc_fasta_file = os.path.join(tmp_dir, config.JUNC_REF_FASTA_FILE)
junc_map_file = os.path.join(tmp_dir, config.JUNC_REF_MAP_FILE)
spanning_read_length = get_read_length(spanning_fastq_file)
if (up_to_date(junc_fasta_file, filtered_encomp_bedpe_file)
and up_to_date(junc_map_file, filtered_encomp_bedpe_file)):
logging.info("[SKIPPED] Extracting junction read sequences")
else:
logging.info("Extracting junction read sequences")
bedpe_to_junction_fasta(filtered_encomp_bedpe_file,
ref_fasta_file, spanning_read_length,
open(junc_fasta_file, "w"),
open(junc_map_file, "w"))
#
# Build a bowtie index to align and detect spanning reads
#
bowtie_spanning_index = os.path.join(tmp_dir, config.JUNC_BOWTIE_INDEX)
bowtie_spanning_index_file = os.path.join(tmp_dir,
config.JUNC_BOWTIE_INDEX_FILE)
if (up_to_date(bowtie_spanning_index_file, junc_fasta_file)):
logging.info(
"[SKIPPED] Building bowtie index for junction-spanning reads")
else:
logging.info("Building bowtie index for junction-spanning reads")
args = [
runconfig.bowtie_build_bin, junc_fasta_file, bowtie_spanning_index
]
f = open(os.path.join(log_dir, "bowtie_build.log"), "w")
subprocess.call(args, stdout=f, stderr=f)
f.close()
#
# Align unmapped reads across putative junctions
#
junc_bam_file = os.path.join(tmp_dir, config.JUNC_READS_BAM_FILE)
junc_log_file = os.path.join(log_dir, "bowtie_spanning_alignment.log")
if (up_to_date(junc_bam_file, bowtie_spanning_index_file)
and up_to_date(junc_bam_file, spanning_fastq_file)):
logging.info("[SKIPPED] Aligning junction spanning reads")
else:
logging.info("Aligning junction spanning reads")
retcode = align_sr_full(spanning_fastq_file,
bowtie_spanning_index,
junc_bam_file,
trim5=runconfig.trim5,
trim3=runconfig.trim3,
num_processors=runconfig.num_processors,
fastq_format=runconfig.fastq_format,
multihits=runconfig.multihits,
mismatches=runconfig.mismatches,
bowtie_bin=runconfig.bowtie_bin,
bowtie_mode=bowtie_mode,
log_file=junc_log_file)
if retcode != 0:
logging.error("Bowtie failed with error code %d" % (retcode))
sys.exit(retcode)
#
# Merge spanning and encompassing read information
#
raw_chimera_bedpe_file = os.path.join(tmp_dir,
config.RAW_CHIMERA_BEDPE_FILE)
if (up_to_date(raw_chimera_bedpe_file, junc_bam_file)
and up_to_date(raw_chimera_bedpe_file, junc_map_file)):
logging.info(
"[SKIPPED] Merging spanning and encompassing read alignments")
else:
logging.info("Merging spanning and encompassing read alignments")
merge_spanning_alignments(junc_bam_file,
junc_map_file,
raw_chimera_bedpe_file,
anchor_min=0,
anchor_max=0,
anchor_mismatches=0)
#
# Choose best isoform for each junction
#
chimera_bedpe_file = os.path.join(tmp_dir, config.CHIMERA_BEDPE_FILE)
if (up_to_date(chimera_bedpe_file, raw_chimera_bedpe_file)):
logging.info("[SKIPPED] Filtering chimeras")
else:
logging.info("Filtering chimeras")
# get insert size at prob
max_isize = isize_dist.percentile(runconfig.filter_isize_percentile)
filter_spanning_chimeras(raw_chimera_bedpe_file,
chimera_bedpe_file,
gene_feature_file,
mate_pval=runconfig.filter_strand_pval,
max_isize=max_isize)
#
# Rank chimeras
#
ranked_chimera_bedpe_file = os.path.join(runconfig.output_dir,
config.RANKED_CHIMERA_BEDPE_FILE)
if (up_to_date(ranked_chimera_bedpe_file, chimera_bedpe_file)):
logging.info("[SKIPPED] Ranking chimeras")
else:
logging.info("Ranking chimeras")
rank_chimeras(chimera_bedpe_file,
ranked_chimera_bedpe_file,
empirical_prob=runconfig.empirical_prob)
#
# Cleanup
#
#shutil.rmtree(tmp_dir)
#
# Done
#
logging.info("Finished run. Chimeras written to file %s" %
(ranked_chimera_bedpe_file))
return JOB_SUCCESS
def check_config(self):
# check that input fastq files exist
config_passed = True
read_lengths = []
for mate, fastq_file in enumerate(self.fastq_files):
if not os.path.isfile(fastq_file):
logging.error("mate '%d' fastq file '%s' is not valid" %
(mate, fastq_file))
config_passed = False
read_lengths.append(get_read_length(fastq_file))
logging.debug("Checking file %s" % (fastq_file))
logging.debug("File %s read length=%d" %
(fastq_file, read_lengths[-1]))
# check that mate read lengths are equal
if len(set(read_lengths)) > 1:
logging.error("Unequal read lengths mate1=%d and mate2=%d" %
(read_lengths[0], read_lengths[1]))
config_passed = False
# check that seed length < read length
if any(self.segment_length > rlen for rlen in read_lengths):
logging.error("seed length %d cannot be longer than read length" %
(self.segment_length))
config_passed = False
# check that output dir is not a regular file
if os.path.exists(
self.output_dir) and (not os.path.isdir(self.output_dir)):
logging.error(
"Output directory name '%s' exists and is not a valid directory"
% (self.output_dir))
config_passed = False
if check_executable(self.bowtie_build_bin):
logging.debug("Checking for 'bowtie-build' binary... found")
else:
logging.error("bowtie-build binary not found or not executable")
config_passed = False
# check that bowtie program exists
if check_executable(self.bowtie_bin):
logging.debug("Checking for 'bowtie' binary... found")
else:
logging.error("bowtie binary not found or not executable")
config_passed = False
# check that alignment index exists
if os.path.isdir(self.index_dir):
logging.debug("Checking for chimerascan index directory... found")
# check that alignment index file exists
align_index_file = os.path.join(self.index_dir,
config.BOWTIE_INDEX_FILE)
if os.path.isfile(align_index_file):
logging.debug("Checking for bowtie index file... found")
else:
logging.error("chimerascan bowtie index file '%s' invalid" %
(align_index_file))
config_passed = False
else:
logging.error(
"chimerascan alignment index directory '%s' not valid" %
(self.index_dir))
config_passed = False
# check for sufficient processors
if self.num_processors < config.BASE_PROCESSORS:
logging.warning(
"Please specify >=2 processes using '-p' to allow program to run efficiently"
)
return config_passed
def run_chimerascan(runconfig):
# normal run
config_passed = runconfig.check_config()
if not config_passed:
logging.error("Invalid run configuration, aborting.")
sys.exit(JOB_ERROR)
# create output dir if it does not exist
if not os.path.exists(runconfig.output_dir):
os.makedirs(runconfig.output_dir)
logging.info("Created output directory: %s" % (runconfig.output_dir))
# create log dir if it does not exist
log_dir = os.path.join(runconfig.output_dir, config.LOG_DIR)
if not os.path.exists(log_dir):
os.makedirs(log_dir)
logging.debug("Created directory for log files: %s" % (log_dir))
# create tmp dir if it does not exist
tmp_dir = os.path.join(runconfig.output_dir, config.TMP_DIR)
if not os.path.exists(tmp_dir):
os.makedirs(tmp_dir)
logging.debug("Created directory for tmp files: %s" % (tmp_dir))
# write the run config to a file
xmlstring = runconfig.to_xml()
runconfig_xml_file = os.path.join(runconfig.output_dir, config.RUNCONFIG_XML_FILE)
fh = open(runconfig_xml_file, "w")
print >>fh, xmlstring
fh.close()
# gather and parse run parameters
library_type = parse_library_type(runconfig.library_type)
gene_feature_file = os.path.join(runconfig.index_dir, config.GENE_FEATURE_FILE)
bowtie_mode = "-v" if runconfig.bowtie_mode_v else "-n"
bowtie_index = os.path.join(runconfig.index_dir, config.ALIGN_INDEX)
original_read_length = get_read_length(runconfig.fastq_files[0])
# minimum fragment length cannot be smaller than the trimmed read length
trimmed_read_length = original_read_length - runconfig.trim5 - runconfig.trim3
min_fragment_length = max(runconfig.min_fragment_length,
trimmed_read_length)
#
# Initial Bowtie alignment step
#
# align in paired-end mode, trying to resolve as many reads as possible
# this effectively rules out the vast majority of reads as candidate
# fusions
unaligned_fastq_param = os.path.join(tmp_dir, config.UNALIGNED_FASTQ_PARAM)
maxmultimap_fastq_param = os.path.join(tmp_dir, config.MAXMULTIMAP_FASTQ_PARAM)
aligned_bam_file = os.path.join(runconfig.output_dir, config.ALIGNED_READS_BAM_FILE)
aligned_log_file = os.path.join(log_dir, "bowtie_alignment.log")
if all(up_to_date(aligned_bam_file, fq) for fq in runconfig.fastq_files):
logging.info("[SKIPPED] Alignment results exist")
else:
logging.info("Aligning full-length reads in paired-end mode")
retcode = align_pe_full(runconfig.fastq_files,
bowtie_index,
aligned_bam_file,
unaligned_fastq_param,
maxmultimap_fastq_param,
min_fragment_length=min_fragment_length,
max_fragment_length=runconfig.max_fragment_length,
trim5=runconfig.trim5,
trim3=runconfig.trim3,
library_type=runconfig.library_type,
num_processors=runconfig.num_processors,
fastq_format=runconfig.fastq_format,
multihits=runconfig.multihits,
mismatches=runconfig.mismatches,
bowtie_bin=runconfig.bowtie_bin,
bowtie_mode=bowtie_mode,
log_file=aligned_log_file)
if retcode != 0:
logging.error("Bowtie failed with error code %d" % (retcode))
sys.exit(retcode)
#
# Get insert size distribution
#
isize_dist_file = os.path.join(runconfig.output_dir, config.ISIZE_DIST_FILE)
isize_dist = InsertSizeDistribution()
if up_to_date(isize_dist_file, aligned_bam_file):
logging.info("[SKIPPED] Profiling insert size distribution")
isize_dist.from_file(open(isize_dist_file, "r"))
else:
logging.info("Profiling insert size distribution")
max_isize_samples = config.ISIZE_MAX_SAMPLES
bamfh = pysam.Samfile(aligned_bam_file, "rb")
isize_dist.from_bam(bamfh, min_isize=min_fragment_length,
max_isize=runconfig.max_fragment_length,
max_samples=max_isize_samples)
isize_dist.to_file(open(isize_dist_file, "w"))
bamfh.close()
logging.info("Insert size samples=%d mean=%f std=%f median=%d mode=%d" %
(isize_dist.n, isize_dist.mean(), isize_dist.std(),
isize_dist.percentile(50.0), isize_dist.mode()))
#
# Discordant reads alignment step
#
discordant_bam_file = os.path.join(tmp_dir, config.DISCORDANT_BAM_FILE)
discordant_log_file = os.path.join(log_dir, "bowtie_segmented_alignment.log")
unaligned_fastq_files = [os.path.join(tmp_dir, fq) for fq in config.UNALIGNED_FASTQ_FILES]
# get the segments used in discordant alignment to know the effective
# read length used to align. we used this to set the 'padding' during
# spanning read discovery
segments = determine_read_segments(original_read_length,
segment_length=runconfig.segment_length,
segment_trim=True,
trim5=runconfig.trim5,
trim3=runconfig.trim3)
segmented_read_length = segments[-1][1]
logging.debug("Segmented alignment will use effective read length of %d" %
(segmented_read_length))
if all(up_to_date(discordant_bam_file, fq) for fq in runconfig.fastq_files):
logging.info("[SKIPPED] Discordant alignment results exist")
else:
logging.info("Aligning initially unmapped reads in single read mode")
align(unaligned_fastq_files, runconfig.fastq_format, bowtie_index,
discordant_bam_file,
bowtie_bin=runconfig.bowtie_bin,
num_processors=runconfig.num_processors,
segment_length=runconfig.segment_length,
segment_trim=True,
trim5=runconfig.trim5,
trim3=runconfig.trim3,
multihits=runconfig.multihits,
mismatches=runconfig.mismatches,
bowtie_mode=bowtie_mode,
best_strata=runconfig.best_strata,
log_file=discordant_log_file)
#
# Merge paired-end reads step
#
paired_bam_file = os.path.join(tmp_dir, config.DISCORDANT_PAIRED_BAM_FILE)
if up_to_date(paired_bam_file, discordant_bam_file):
logging.info("[SKIPPED] Read pairing results exist")
else:
logging.info("Pairing aligned reads")
bamfh = pysam.Samfile(discordant_bam_file, "rb")
paired_bamfh = pysam.Samfile(paired_bam_file, "wb", template=bamfh)
merge_read_pairs(bamfh, paired_bamfh,
runconfig.min_fragment_length,
runconfig.max_fragment_length,
library_type)
paired_bamfh.close()
bamfh.close()
#
# Find discordant reads step
#
discordant_gene_bedpe_file = \
os.path.join(tmp_dir, config.DISCORDANT_GENE_BEDPE_FILE)
discordant_genome_bedpe_file = \
os.path.join(tmp_dir, config.DISCORDANT_GENOME_BEDPE_FILE)
padding = original_read_length - segmented_read_length
if (up_to_date(discordant_gene_bedpe_file, paired_bam_file) and
up_to_date(discordant_genome_bedpe_file, paired_bam_file)):
logging.info("[SKIPPED] Finding discordant reads")
else:
logging.info("Finding discordant reads")
bamfh = pysam.Samfile(paired_bam_file, "rb")
find_discordant_reads(bamfh,
discordant_gene_bedpe_file,
discordant_genome_bedpe_file,
gene_feature_file,
max_indel_size=runconfig.max_indel_size,
max_isize=runconfig.max_fragment_length,
max_multihits=runconfig.multihits,
library_type=library_type,
padding=padding)
bamfh.close()
#
# Extract full sequences of the discordant reads
#
extended_discordant_gene_bedpe_file = \
os.path.join(tmp_dir,
config.EXTENDED_DISCORDANT_GENE_BEDPE_FILE)
if up_to_date(extended_discordant_gene_bedpe_file, discordant_gene_bedpe_file):
logging.info("[SKIPPED] Retrieving full length sequences for realignment")
else:
logging.info("Retrieving full length sequences for realignment")
extend_sequences(unaligned_fastq_files,
discordant_gene_bedpe_file,
extended_discordant_gene_bedpe_file)
#
# Sort discordant reads
#
sorted_discordant_gene_bedpe_file = os.path.join(tmp_dir, config.SORTED_DISCORDANT_GENE_BEDPE_FILE)
if (up_to_date(sorted_discordant_gene_bedpe_file, extended_discordant_gene_bedpe_file)):
logging.info("[SKIPPED] Sorting discordant BEDPE file")
else:
logging.info("Sorting discordant BEDPE file")
sort_discordant_reads(extended_discordant_gene_bedpe_file, sorted_discordant_gene_bedpe_file)
#
# Nominate chimeras step
#
encompassing_bedpe_file = os.path.join(tmp_dir, config.ENCOMPASSING_CHIMERA_BEDPE_FILE)
if (up_to_date(encompassing_bedpe_file, sorted_discordant_gene_bedpe_file)):
logging.info("[SKIPPED] Nominating chimeras from discordant reads")
else:
logging.info("Nominating chimeras from discordant reads")
nominate_chimeras(open(sorted_discordant_gene_bedpe_file, "r"),
open(encompassing_bedpe_file, "w"),
gene_feature_file,
trim=config.EXON_JUNCTION_TRIM_BP)
#
# Filter encompassing chimeras step
#
filtered_encomp_bedpe_file = \
os.path.join(tmp_dir,
config.FILTERED_ENCOMPASSING_CHIMERA_BEDPE_FILE)
if (up_to_date(filtered_encomp_bedpe_file, encompassing_bedpe_file)):
logging.info("[SKIPPED] Filtering encompassing chimeras")
else:
logging.info("Filtering encompassing chimeras")
# max_isize = isize_mean + runconfig.filter_isize_stdevs*isize_std
filter_encompassing_chimeras(encompassing_bedpe_file,
filtered_encomp_bedpe_file,
gene_feature_file,
max_multimap=runconfig.filter_max_multimaps,
multimap_cov_ratio=runconfig.filter_multimap_ratio,
max_isize=-1,
strand_pval=runconfig.filter_strand_pval)
#
# Nominate spanning reads step
#
spanning_fastq_file = os.path.join(runconfig.output_dir,
config.SPANNING_FASTQ_FILE)
if all(up_to_date(spanning_fastq_file, f) for f in unaligned_fastq_files):
logging.info("[SKIPPED] Preparing junction spanning reads")
else:
logging.info("Preparing junction spanning reads")
outfh = open(spanning_fastq_file, "w")
for f in unaligned_fastq_files:
shutil.copyfileobj(open(f), outfh)
outfh.close()
# TODO: skip this step for now, and simply realign all the reads
# spanning_fastq_file = os.path.join(runconfig.output_dir, config.SPANNING_FASTQ_FILE)
# if (up_to_date(spanning_fastq_file, extended_discordant_bedpe_file) and
# up_to_date(spanning_fastq_file, filtered_encomp_bedpe_file)):
# logging.info("[SKIPPED] Nominating junction spanning reads")
# else:
# logging.info("Nominating junction spanning reads")
# nominate_spanning_reads(open(extended_discordant_bedpe_file, 'r'),
# open(filtered_encomp_bedpe_file, 'r'),
# open(spanning_fastq_file, 'w'))
#
# Extract junction sequences from chimeras file
#
ref_fasta_file = os.path.join(runconfig.index_dir, config.ALIGN_INDEX + ".fa")
junc_fasta_file = os.path.join(tmp_dir, config.JUNC_REF_FASTA_FILE)
junc_map_file = os.path.join(tmp_dir, config.JUNC_REF_MAP_FILE)
spanning_read_length = get_read_length(spanning_fastq_file)
if (up_to_date(junc_fasta_file, filtered_encomp_bedpe_file) and
up_to_date(junc_map_file, filtered_encomp_bedpe_file)):
logging.info("[SKIPPED] Extracting junction read sequences")
else:
logging.info("Extracting junction read sequences")
bedpe_to_junction_fasta(filtered_encomp_bedpe_file, ref_fasta_file,
spanning_read_length,
open(junc_fasta_file, "w"),
open(junc_map_file, "w"))
#
# Build a bowtie index to align and detect spanning reads
#
bowtie_spanning_index = os.path.join(tmp_dir, config.JUNC_BOWTIE_INDEX)
bowtie_spanning_index_file = os.path.join(tmp_dir, config.JUNC_BOWTIE_INDEX_FILE)
if (up_to_date(bowtie_spanning_index_file, junc_fasta_file)):
logging.info("[SKIPPED] Building bowtie index for junction-spanning reads")
else:
logging.info("Building bowtie index for junction-spanning reads")
args = [runconfig.bowtie_build_bin, junc_fasta_file, bowtie_spanning_index]
f = open(os.path.join(log_dir, "bowtie_build.log"), "w")
subprocess.call(args, stdout=f, stderr=f)
f.close()
#
# Align unmapped reads across putative junctions
#
junc_bam_file = os.path.join(tmp_dir, config.JUNC_READS_BAM_FILE)
junc_log_file = os.path.join(log_dir, "bowtie_spanning_alignment.log")
if (up_to_date(junc_bam_file, bowtie_spanning_index_file) and
up_to_date(junc_bam_file, spanning_fastq_file)):
logging.info("[SKIPPED] Aligning junction spanning reads")
else:
logging.info("Aligning junction spanning reads")
retcode = align_sr_full(spanning_fastq_file,
bowtie_spanning_index,
junc_bam_file,
trim5=runconfig.trim5,
trim3=runconfig.trim3,
num_processors=runconfig.num_processors,
fastq_format=runconfig.fastq_format,
multihits=runconfig.multihits,
mismatches=runconfig.mismatches,
bowtie_bin=runconfig.bowtie_bin,
bowtie_mode=bowtie_mode,
log_file=junc_log_file)
if retcode != 0:
logging.error("Bowtie failed with error code %d" % (retcode))
sys.exit(retcode)
#
# Merge spanning and encompassing read information
#
raw_chimera_bedpe_file = os.path.join(tmp_dir, config.RAW_CHIMERA_BEDPE_FILE)
if (up_to_date(raw_chimera_bedpe_file, junc_bam_file) and
up_to_date(raw_chimera_bedpe_file, junc_map_file)):
logging.info("[SKIPPED] Merging spanning and encompassing read alignments")
else:
logging.info("Merging spanning and encompassing read alignments")
merge_spanning_alignments(junc_bam_file, junc_map_file,
raw_chimera_bedpe_file,
anchor_min=0,
anchor_max=0,
anchor_mismatches=0)
#
# Choose best isoform for each junction
#
chimera_bedpe_file = os.path.join(tmp_dir, config.CHIMERA_BEDPE_FILE)
if (up_to_date(chimera_bedpe_file, raw_chimera_bedpe_file)):
logging.info("[SKIPPED] Filtering chimeras")
else:
logging.info("Filtering chimeras")
# get insert size at prob
max_isize = isize_dist.percentile(runconfig.filter_isize_percentile)
filter_spanning_chimeras(raw_chimera_bedpe_file,
chimera_bedpe_file,
gene_feature_file,
mate_pval=runconfig.filter_strand_pval,
max_isize=max_isize)
#
# Rank chimeras
#
ranked_chimera_bedpe_file = os.path.join(runconfig.output_dir,
config.RANKED_CHIMERA_BEDPE_FILE)
if (up_to_date(ranked_chimera_bedpe_file, chimera_bedpe_file)):
logging.info("[SKIPPED] Ranking chimeras")
else:
logging.info("Ranking chimeras")
rank_chimeras(chimera_bedpe_file, ranked_chimera_bedpe_file,
empirical_prob=runconfig.empirical_prob)
#
# Cleanup
#
#shutil.rmtree(tmp_dir)
#
# Done
#
logging.info("Finished run. Chimeras written to file %s" %
(ranked_chimera_bedpe_file))
return JOB_SUCCESS
