def _generate_pileups(self):
bam_file = pysam.AlignmentFile(self.bam_file_path)
info_of_interest = ['A', 'C', 'G', 'T', 'insertions', 'deletions']
indel_positions = [4, 5]
# Last number in shape - 5 - is for letters other than A, C, G and T.
mapping = {
'A': 0,
'a': 0,
'C': 1,
'c': 1,
'G': 2,
'g': 2,
'T': 3,
't': 3
}
total_options = len(info_of_interest) + 1
pileups = [
np.zeros((bam_file.get_reference_length(contig_name),
len(info_of_interest)))
for contig_name in bam_file.references
]
y_oh = [
np.zeros(
(bam_file.get_reference_length(contig_name), total_options))
for contig_name in bam_file.references
]
total_length = np.sum([
bam_file.get_reference_length(contig_name)
for contig_name in bam_file.references
])
progress_counter = 0
contig_names = bam_file.references
with progressbar.ProgressBar(max_value=total_length) as progress_bar:
for contig_id, contig_name in enumerate(contig_names):
for record in pysamstats.stat_variation(
bam_file,
chrom=contig_name,
fafile=self.reference_fasta_path):
progress_bar.update(progress_counter)
progress_counter += 1
curr_position = record['pos']
for i, info in enumerate(info_of_interest):
pileups[contig_id][curr_position][i] += record[info]
pileup_argmax = np.argmax(
pileups[contig_id][curr_position])
if pileup_argmax in indel_positions:
y_oh[contig_id][curr_position][pileup_argmax] = 1
else:
y_oh[contig_id][curr_position][mapping.get(
record['ref'], -1)] = 1
return pileups, y_oh, contig_names
def populateDict():
global holdingDict
if not os.path.isfile(JSONProfile):
for rec in pysamstats.stat_variation(alignmentfile=bamFile, fafile=target):
# holdingDict[rec['chrom'].split("_")[0]] = {}
# geneName = rec['chrom'].split(".")[0]
aros = re.findall("(?<=ARO:)3\d{6}", rec['chrom'])
aro = " ".join(aros)
# if len(aros) > 1:
# print str(aros)
# aros = rec['chrom'].split("!")[1].split("_")[0]
if rec['matches'] - rec['mismatches'] > 0:
holdingDict[rec['chrom']][int(rec['pos'])] = rec['reads_all']
dotter()
JSONreport = open(JSONProfile, "wb")
output = json.dumps(holdingDict, sort_keys=True, indent=4, separators=(',', ': '))
JSONreport.write(output)
JSONreport.close()
else:
with open(JSONProfile, "rb") as jsonReport:
# Load the data
# print strain, targetName, JSONProfile, jsonReport
holdingDict.update(json.load(jsonReport))
def parse_bam(bam, Chr, Pos, End, Ref, Alt, REF, ):
# exec_pysamstats = '/home/liaoth/tools/pysamstats_venv/bin/pysamstats'
#
# t_result = os.popen(
# '{exe} --fasta {fa} --type variation {t_f} -c {chr} -s {start} -e {end} -u'
# .format(exe=exec_pysamstats, fa=fasta, t_f=bam_path, chr=Chr, start=Pos, end=End + 1)).read()
result = pysamstats.stat_variation(bam,
REF,
chrom=Chr,
start=Pos,
end=End + 1,
truncate=True,
one_based=True)
result_dict = {}
for idx, record in enumerate(result):
result_dict[idx] = record
data_df = pd.DataFrame.from_dict(result_dict, orient='index')
if data_df.shape[0] == 0:
data_df = data_df.append(pd.DataFrame(columns=tmp))
data_df.loc[0, :] = 0
if Ref in ['A', 'C', 'G', 'T'] and Alt in ['A', 'C', 'G', 'T']:
ref_cov, mut_cov, cov = data_df.loc[0,
[Ref + '_pp',
Alt + '_pp',
'reads_pp']]
if cov != 0:
mut_per = mut_cov / float(cov)
else:
mut_per = 0
else:
if data_df.sum()['reads_pp'] > 0 and len(data_df) > 0:
if Ref == '-' or len(Alt) > len(Ref):
# insertions
mut_per = data_df.sum()['insertions_pp'] / float(data_df.sum()['reads_pp'])
ref_cov = data_df.sum()['matches_pp'] / float(len(data_df))
mut_cov = data_df.sum()['insertions_pp'] / float(len(data_df))
elif Alt == '-' or len(Ref) > len(Alt):
# deletions
mut_per = data_df.sum(0)['deletions_pp'] / float(data_df.sum()['reads_pp'])
ref_cov = data_df.sum(0)['matches_pp'] / float(len(data_df))
mut_cov = data_df.sum(0)['deletions_pp'] / float(len(data_df))
else:
return ['Wrong pos'] * 3
else:
return ['Off target'] * 3
return mut_cov, mut_per, ref_cov
def filter_germline(chr, t_columns_pos, ref_seq, alt_base):
n_alt_A=0; n_alt_C=0; n_alt_G=0; n_alt_T=0; n_refcount=0
for rec in pysamstats.stat_variation(n_samfile, ref, chrom=str(chr), start=int(t_columns_pos), end=int(t_columns_pos)+1):
chr = rec['chrom']; pos = rec['pos']; ref_seq = rec['ref']
if pos == t_columns_pos:
if rec['reads_pp'] > 4:
if float(rec['mismatches_pp']/rec['reads_pp']) <= 0.10:
for n_columns in n_samfile.pileup(chr, int(t_columns_pos), int(t_columns_pos)+1, truncate=True):
if n_columns.pos == t_columns_pos:
(n_alt_A, n_alt_C, n_alt_G, n_alt_T, n_refcount) = process_reads(n_columns, n_columns.pos, ref_seq, "N");
else:
n_alt_A = rec['mismatches_pp']; n_alt_C = rec['mismatches_pp']; n_alt_G = rec['mismatches_pp']; n_alt_T = rec['mismatches_pp']; n_refcount = rec['reads_pp']-rec['mismatches_pp']
else:
n_alt_A=0; n_alt_G=0; n_alt_C=0; n_alt_T=0; n_refcount=rec['reads_pp']
if alt_base == "A":
return n_alt_A, n_refcount
if alt_base == "G":
return n_alt_G, n_refcount
if alt_base == "T":
return n_alt_T, n_refcount
if alt_base == "C":
return n_alt_C, n_refcount
def parse(self):
import pysamstats
import operator
import numpy
while True:
sample, analysistype = self.parsequeue.get()
# Initialise dictionaries to store parsed data
matchdict = dict()
depthdict = dict()
seqdict = dict()
snpdict = dict()
gapdict = dict()
maxdict = dict()
mindict = dict()
deviationdict = dict()
sample[analysistype].results = dict()
sample[analysistype].avgdepth = dict()
sample[analysistype].resultssnp = dict()
sample[analysistype].resultsgap = dict()
sample[analysistype].sequences = dict()
sample[analysistype].maxcoverage = dict()
sample[analysistype].mincoverage = dict()
sample[analysistype].standarddev = dict()
# Variable to store the expected position in gene/allele
pos = 0
try:
# Use the stat_variation function of pysam stats to return records parsed from sorted bam files
# Values of interest can be retrieved using the appropriate keys
for rec in pysamstats.stat_variation(alignmentfile=sample[analysistype].sortedbam,
fafile=sample[analysistype].baitfile,
max_depth=1000000):
# Initialise seqdict with the current gene/allele if necessary with an empty string
if rec['chrom'] not in seqdict:
seqdict[rec['chrom']] = str()
# Since this is the first position in a "new" gene/allele, reset the pos variable to 0
pos = 0
# Initialise gap dict with 0 gaps
if rec['chrom'] not in gapdict:
gapdict[rec['chrom']] = 0
# If there is a gap in the alignment, record the size of the gap in gapdict
if int(rec['pos']) > pos:
# Add the gap size to gap dict
gapdict[rec['chrom']] += rec['pos'] - pos
# Set the expected position to the current position
pos = int(rec['pos'])
# Increment pos in preparation for the next iteration
pos += 1
# Initialise snpdict if necessary
if rec['chrom'] not in snpdict:
snpdict[rec['chrom']] = 0
# Initialise the current gene/allele in depthdict with the depth (reads_all) if necessary,
# otherwise add the current depth to the running total
if rec['chrom'] not in depthdict:
depthdict[rec['chrom']] = int(rec['reads_all'])
else:
depthdict[rec['chrom']] += int(rec['reads_all'])
# Dictionary of bases and the number of times each base was observed per position
bases = {'A': rec['A'], 'C': rec['C'], 'G': rec['G'], 'T': rec['T']}
# If the most prevalent base (calculated with max() and operator.itemgetter()) does not match the
# reference base, add this prevalent base to seqdict
if max(bases.items(), key=operator.itemgetter(1))[0] != rec['ref']:
seqdict[rec['chrom']] += max(bases.items(), key=operator.itemgetter(1))[0]
# Increment the running total of the number of SNPs
snpdict[rec['chrom']] += 1
else:
# If the bases match, add the reference base to seqdict
seqdict[rec['chrom']] += (rec['ref'])
# Initialise posdict if necessary, otherwise, increment the running total of matches
if rec['chrom'] not in matchdict:
matchdict[rec['chrom']] = 1
else:
matchdict[rec['chrom']] += 1
# Find the max and min coverage for each strain/gene combo
try:
maxdict[rec['chrom']] = int(rec['reads_all']) if \
int(rec['reads_all']) >= maxdict[rec['chrom']] else maxdict[rec['chrom']]
except KeyError:
maxdict[rec['chrom']] = int(rec['reads_all'])
try:
mindict[rec['chrom']] = int(rec['reads_all']) if \
int(rec['reads_all']) <= mindict[rec['chrom']] else mindict[rec['chrom']]
except KeyError:
mindict[rec['chrom']] = int(rec['reads_all'])
# Create a list of all the depths in order to calculate the standard deviation
try:
deviationdict[rec['chrom']].append(int(rec['reads_all']))
except KeyError:
deviationdict[rec['chrom']] = list()
deviationdict[rec['chrom']].append(int(rec['reads_all']))
# If there are no results in the bam file, then pass over the strain
except ValueError:
pass
# Iterate through all the genes/alleles with results above
for allele in sorted(matchdict):
# If the length of the match is greater or equal to the length of the gene/allele (multiplied by the
# cutoff value) as determined using faidx indexing, then proceed
if matchdict[allele] >= sample[analysistype].faidict[allele] * self.cutoff:
# Calculate the average depth by dividing the total number of reads observed by the
# length of the gene
averagedepth = float(depthdict[allele]) / float(matchdict[allele])
percentidentity = float(matchdict[allele]) / float(sample[analysistype].faidict[allele]) * 100
# Only report a positive result if this average depth is greater than 10X
if averagedepth > 10:
# Populate resultsdict with the gene/allele name, the percent identity, and the average depth
sample[analysistype].results.update({allele: '{:.2f}'.format(percentidentity)})
sample[analysistype].avgdepth.update({allele: '{:.2f}'.format(averagedepth)})
# Add the SNP and gap results to dictionaries
sample[analysistype].resultssnp.update({allele: snpdict[allele]})
sample[analysistype].resultsgap.update({allele: gapdict[allele]})
sample[analysistype].sequences.update({allele: seqdict[allele]})
sample[analysistype].maxcoverage.update({allele: maxdict[allele]})
sample[analysistype].mincoverage.update({allele: mindict[allele]})
sample[analysistype]\
.standarddev.update({allele: '{:.2f}'.format(numpy.std(deviationdict[allele], ddof=1))})
self.parsequeue.task_done()
ref_genome='' if 'mature' in file: ref_genome='../../../Reference_Genomes/Modifications_files/Ref_seq/families_tRNA_refgenome.fa' if 'PG' in file: ref_genome='../../../Reference_Genomes/Modifications_files/Ref_seq/precursor_tRNA_refgenome.fa' file_base_call=open(sample+'_'+bam_type+'_'+'base_calling_CORRECT_OK.txt','w') #BASE CALLING #pysam will give us the base calling for each trna (max_depth is used becouse by default the maximum number of reads that will read in a position is 8000, so we increse the number to a high number in order to have the total number of reads correct in a ceratin position.) for record in pysamstats.stat_variation(bamfile, fafile=ref_genome, max_depth=10000000): ref_base=record['ref'] tRNA_info='REF-'+str(record['ref'])+':'+str(record[ref_base])+' '+'A:'+str(record['A'])+' '+'C:'+str(record['C'])+' '+'G:'+str(record['G'])+' '+'T:'+str(record['T']) tRNA=record['chrom'] pos='' ref=record['ref'] #Positions of the precursor are not the same as the positions in the mature genome since we have the leading and trailing regions and the introns. So we have to transform the positions from the precursor genome to be like the mature ones. if bam_type=='precursor': pos_i=record['pos'] #take in to acount the leading and trailing regions. if pos_i > 49 and pos_i < int(prec_length[tRNA])-50: pos=pos_i-49
def parse_bam(
bam,
Chr,
Pos,
End,
Ref,
Alt,
REF,
sig='N',
):
#exec_pysamstats = '/home/liaoth/tools/pysamstats_venv/bin/pysamstats'
#
# t_result = os.popen(
# '{exe} --fasta {fa} --type variation {t_f} -c {chr} -s {start} -e {end} -u'
# .format(exe=exec_pysamstats, fa=fasta, t_f=bam_path, chr=Chr, start=Pos, end=End + 1)).read()
result = pysamstats.stat_variation(bam,
REF,
chrom=Chr,
start=Pos,
end=End + 1,
truncate=True,
one_based=True)
result_dict = {}
for idx, record in enumerate(result):
result_dict[idx] = record
t_data_df = pd.DataFrame.from_dict(result_dict, orient='index')
if t_data_df.shape[0] == 0:
t_data_df = t_data_df.append(pd.DataFrame(columns=tmp))
t_data_df.loc[0, :] = 0
if Ref in ['A', 'C', 'G', 'T'] and Alt in ['A', 'C', 'G', 'T']:
T_ref_cov, T_mut_cov, T_cov = t_data_df.loc[
0, [Ref + '_pp', Alt + '_pp', 'reads_pp']]
if T_cov != 0:
T_mut_per = T_mut_cov / float(T_cov)
else:
T_mut_per = 0
added_col['%s_mut_per' % sig].append(T_mut_per)
added_col['%s_ref_cov' % sig].append(T_ref_cov)
added_col['%s_mut_cov' % sig].append(T_mut_cov)
else:
if t_data_df.sum()['reads_pp'] > 0 and len(t_data_df) > 0:
if Ref == '-' or len(Alt) > len(Ref):
# insertions
added_col['%s_mut_per' %
sig].append(t_data_df.sum()['insertions_pp'] /
float(t_data_df.sum()['reads_pp']))
added_col['%s_ref_cov' % sig].append(
t_data_df.sum()['matches_pp'] / float(len(t_data_df)))
added_col['%s_mut_cov' % sig].append(
t_data_df.sum()['insertions_pp'] / float(len(t_data_df)))
elif Alt == '-' or len(Ref) > len(Alt):
# deletions
added_col['%s_mut_per' % sig].append(
t_data_df.sum(0)['deletions_pp'] /
float(t_data_df.sum()['reads_pp']))
added_col['%s_ref_cov' % sig].append(
t_data_df.sum(0)['matches_pp'] / float(len(t_data_df)))
added_col['%s_mut_cov' % sig].append(
t_data_df.sum(0)['deletions_pp'] / float(len(t_data_df)))
else:
for _key in [_ for _ in added_col.keys() if sig in _]:
added_col[_key].append('Wrong pos')
else:
for _key in [_ for _ in added_col.keys() if sig in _]:
added_col[_key].append('Off target')
import pysam
import pysamstats
bamfile = pysam.AlignmentFile('picared.bam')
print("P"),
print("A"),
print("C"),
print("G"),
print("T"),
print("I"),
print("D")
for record in pysamstats.stat_variation(bamfile,
chrom='gi|11|ref|TL|E1E2J6',
fafile="ref_E1E2.fa"):
print(record['pos']),
print(record['A']),
print(record['C']),
print(record['G']),
print(record['T']),
print(record['insertions']),
print(record['deletions'])
if alt_base == "A":
return n_alt_A, n_refcount
if alt_base == "G":
return n_alt_G, n_refcount
if alt_base == "T":
return n_alt_T, n_refcount
if alt_base == "C":
return n_alt_C, n_refcount
foundReg=[]; raws=[]
cov = 0
ftemp = open(tempfile, 'w')
print >>ftemp, "#chr\tpos\tref\talt\tt_ref\tt_alt\tn_ref\tn_alt\tjudge"
print "calling raw variants..."
for bedline in ( raw.strip().split() for raw in open(bed)):
for rec in pysamstats.stat_variation(t_samfile, ref, chrom=str(bedline[0]), start=int(bedline[1]), end=int(bedline[2])):
if rec['reads_pp'] > 4:
if (rec['mismatches_pp'] > 2) and (rec['insertions'] <= 3) and (rec['deletions'] <= 3):
chr = rec['chrom']; pos = rec['pos'];
ref_seq = rec['ref']
for t_columns in t_samfile.pileup(chr, int(pos), int(pos)+1, truncate=True):
try:
foundReg.index(str(chr)+"\t"+str(t_columns.pos))
except ValueError:
foundReg.append(str(chr)+"\t"+str(t_columns.pos))
(t_alt_A, t_alt_C, t_alt_G, t_alt_T, t_refcount, altReadPosE_f_A, altReadPosE_r_A, altReadPosE_f_G, altReadPosE_r_G, altReadPosE_f_C, altReadPosE_r_C, altReadPosE_f_T, altReadPosE_r_T, altReadPosS_f_A, altReadPosS_r_A, altReadPosS_f_G, altReadPosS_r_G, altReadPosS_f_C, altReadPosS_r_C, altReadPosS_f_T, altReadPosS_r_T) = process_reads(t_columns, t_columns.pos, ref_seq, "Y")
totalcount = t_refcount + t_alt_A + t_alt_G + t_alt_C + t_alt_T
if totalcount > 4:
if (t_alt_A > tumor_alt_cutoff) and ((t_alt_A/totalcount) > tumor_alf_cutoff):
if (all(5 >= i for i in altReadPosS_f_A) and all(5 >= i for i in altReadPosS_r_A)) or (all(5 >= i for i in altReadPosE_f_A) and all(5 >= i for i in altReadPosE_r_A)):
raw_calls = (chr+"\t"+str(pos+1)+"\t"+ref_seq.upper()+"\t"+"A"+"\t"+str(t_refcount)+"\t"+str(t_alt_A)+"\t"+"0"+"\t"+"0"+"\t"+"clustered_pos")
def parse(self):
import pysamstats
import operator
while True:
sample, vtx = self.parsequeue.get()
# Initialise dictionaries to store parsed data
matchdict = dict()
depthdict = dict()
seqdict = dict()
resultsdict = dict()
snpdict = dict()
gapdict = dict()
faidict = dict()
uniqueresults = dict()
refdict = dict()
# Variable to store the expected position in gene/allele
pos = 0
# Get the fai file into a dictionary to be used in parsing results
with open(sample[self.analysistype].faifile[vtx], 'rb') as faifile:
for line in faifile:
data = line.split('\t')
faidict[data[0]] = int(data[1])
try:
# Use the stat_variation function of pysam stats to return records parsed from sorted bam files
# Values of interest can be retrieved using the appropriate keys
correction = 0
for rec in pysamstats.stat_variation(alignmentfile=sample[self.analysistype].sortedbam[vtx],
fafile=sample[self.analysistype].targetfiles[vtx],
max_depth=1000000):
# Add the reference sequence to the dictionary
if rec['chrom'] not in refdict:
refdict[rec['chrom']] = str()
refdict[rec['chrom']] += rec['ref']
# Initialise seqdict with the current gene/allele if necessary with an empty string
if rec['chrom'] not in seqdict:
seqdict[rec['chrom']] = str()
# Since this is the first position in a "new" gene/allele, reset the pos variable to 0
pos = 0
# There seems to be a bug in pysamstats with how gaps at the start of the sequence are treated.
# Although the position is correct, the whole reference sequence is still included, rather than
# starting at where the gap ends
if rec['pos'] > pos:
# If there is a gap of 173 bases at the beginning of the match, the reference sequence
# still should start at 0, but it starts at 173, therefore, the match actually starts at
# 2 * 173 = 346
correction = 2 * rec['pos']
# The number of gaps is equal to the starting position
gapdict[rec['chrom']] = rec['pos']
# The actual position will be rec['pos']
pos = rec['pos']
# Allow the position to reach the calculated correction factor
if rec['pos'] >= correction:
# Initialise gap dict with 0 gaps
if rec['chrom'] not in gapdict:
gapdict[rec['chrom']] = 0
# If there is a gap in the alignment, record the size of the gap in gapdict
if int(rec['pos']) > pos:
# Add the gap size to gap dict
gapdict[rec['chrom']] += rec['pos'] - pos
# Add dashes to the sequence to indicate the gap
seqdict[rec['chrom']] += 'N' * (int(rec['pos'] - pos))
# Set the expected position to the current position
pos = int(rec['pos'])
# Increment pos in preparation for the next iteration
pos += 1
# Initialise snpdict if necessary
if rec['chrom'] not in snpdict:
snpdict[rec['chrom']] = 0
# Initialise the current gene/allele in depthdict with the depth (reads_all) if necessary,
# otherwise add the current depth to the running total
if rec['chrom'] not in depthdict:
depthdict[rec['chrom']] = int(rec['reads_all'])
else:
depthdict[rec['chrom']] += int(rec['reads_all'])
# Dictionary of bases and the number of times each base was observed per position
bases = {'A': rec['A'], 'C': rec['C'], 'G': rec['G'], 'T': rec['T']}
# Track any deletions prior to the sequence
if rec['deletions'] > rec['matches']:
seqdict[rec['chrom']] += 'N'
# Increment the running total of the number of SNPs
snpdict[rec['chrom']] += 1
else:
if rec['matches'] > 0 or rec['mismatches'] > 0:
# If the most prevalent base (calculated with max() and operator.itemgetter())
# doesn't match the reference base, add this prevalent base to seqdict
if max(bases.iteritems(), key=operator.itemgetter(1))[0] != rec['ref']:
seqdict[rec['chrom']] += max(bases.iteritems(), key=operator.itemgetter(1))[0]
# Increment the running total of the number of SNPs
snpdict[rec['chrom']] += 1
else:
# If the bases match, add the reference base to seqdict
seqdict[rec['chrom']] += (rec['ref'])
# Initialise posdict if necessary, otherwise, increment the running total of matches
if rec['chrom'] not in matchdict:
matchdict[rec['chrom']] = 1
else:
matchdict[rec['chrom']] += 1
# If there are no results in the bam file, then pass over the strain
except ValueError:
pass
# Iterate through all the genes/alleles with results above
for allele in sorted(matchdict):
# If the length of the match is greater or equal to the length of the gene/allele (multiplied by the
# cutoff value) as determined using faidx indexing, then proceed
# Calculate the average depth by dividing the total number of reads observed by the length of the gene
averagedepth = float(depthdict[allele]) / float(matchdict[allele])
percentidentity = float(matchdict[allele]) / float(faidict[allele]) * 100
if percentidentity == self.cutoff * 100:
# Only report a positive result if this average depth is greater than 4X
if averagedepth > 4:
# Populate resultsdict with the gene/allele name, the percent identity, and the average depth
resultsdict.update({allele: {'{:.2f}'.format(percentidentity): '{:.2f}'.format(averagedepth)}})
# Add the results to the object
sample[self.analysistype].allelematches[vtx] = resultsdict
# Determine if there are alleles without a 100% match
if not resultsdict:
for allele in sorted(matchdict):
# Filter the alleles to only include the vtx subunit
if vtx in allele:
percentidentity = float(matchdict[allele]) / float(faidict[allele]) * 100
# Use a more relaxed cutoff to find the closest alleles
if percentidentity >= self.cutoff * 50:
uniqueresults.update({allele: percentidentity})
try:
# Find the best match (highest percent identity)
closestallele = max(uniqueresults.iteritems(), key=operator.itemgetter(1))[0]
percentidentity = max(uniqueresults.iteritems(), key=operator.itemgetter(1))[1]
averagedepth = float(depthdict[closestallele]) / float(matchdict[closestallele])
# Populate the metadata with the results
sample[self.analysistype].newsequences[vtx] = seqdict[closestallele]
sample[self.analysistype].newseqclosestmatch[vtx] = \
{closestallele: {'{:.2f}'.format(percentidentity): '{:.2f}'.format(averagedepth)}}
sample[self.analysistype].newseqclosestseq[vtx] = {closestallele: refdict[closestallele]}
except ValueError:
pass
self.parsequeue.task_done()
