#include <string.h>
#include "bam.h"
#include "bam2bcf.h"
-#include "ksort.h"
#include "kaln.h"
#include "kprobaln.h"
#include "khash.h"
KHASH_SET_INIT_STR(rg)
+#include "ksort.h"
+KSORT_INIT_GENERIC(uint32_t)
+
#define MINUS_CONST 0x10000000
#define INDEL_WINDOW_SIZE 50
-#define MIN_SUPPORT_COEF 500
void *bcf_call_add_rg(void *_hash, const char *hdtext, const char *list)
{
for (k = 0; k < c->n_cigar; ++k) {
int op = cigar[k] & BAM_CIGAR_MASK;
int l = cigar[k] >> BAM_CIGAR_SHIFT;
- if (op == BAM_CMATCH) {
+ if (op == BAM_CMATCH || op == BAM_CEQUAL || op == BAM_CDIFF) {
if (c->pos > tpos) return y;
if (x + l > tpos) {
*_tpos = tpos;
return max_i - pos;
}
+/*
+ * @n: number of samples
+ */
int bcf_call_gap_prep(int n, int *n_plp, bam_pileup1_t **plp, int pos, bcf_callaux_t *bca, const char *ref,
const void *rghash)
{
- extern void ks_introsort_uint32_t(int, uint32_t*);
int i, s, j, k, t, n_types, *types, max_rd_len, left, right, max_ins, *score1, *score2, max_ref2;
int N, K, l_run, ref_type, n_alt;
- char *inscns = 0, *ref2, *query;
+ char *inscns = 0, *ref2, *query, **ref_sample;
khash_t(rg) *hash = (khash_t(rg)*)rghash;
if (ref == 0 || bca == 0) return -1;
// mark filtered reads
if (s == n) return -1; // there is no indel at this position.
for (s = N = 0; s < n; ++s) N += n_plp[s]; // N is the total number of reads
{ // find out how many types of indels are present
- int m, n_alt = 0, n_tot = 0;
+ bca->max_support = bca->max_frac = 0;
+ int m, n_alt = 0, n_tot = 0, indel_support_ok = 0;
uint32_t *aux;
aux = calloc(N + 1, 4);
m = max_rd_len = 0;
aux[m++] = MINUS_CONST; // zero indel is always a type
for (s = 0; s < n; ++s) {
+ int na = 0, nt = 0;
for (i = 0; i < n_plp[s]; ++i) {
const bam_pileup1_t *p = plp[s] + i;
if (rghash == 0 || p->aux == 0) {
- ++n_tot;
+ ++nt;
if (p->indel != 0) {
- ++n_alt;
+ ++na;
aux[m++] = MINUS_CONST + p->indel;
}
}
j = bam_cigar2qlen(&p->b->core, bam1_cigar(p->b));
if (j > max_rd_len) max_rd_len = j;
}
+ float frac = (float)na/nt;
+ if ( !indel_support_ok && na >= bca->min_support && frac >= bca->min_frac )
+ indel_support_ok = 1;
+ if ( na > bca->max_support && frac > 0 ) bca->max_support = na, bca->max_frac = frac;
+ n_alt += na;
+ n_tot += nt;
}
+ // To prevent long stretches of N's to be mistaken for indels (sometimes thousands of bases),
+ // check the number of N's in the sequence and skip places where half or more reference bases are Ns.
+ int nN=0; for (i=pos; i-pos<max_rd_len && ref[i]; i++) if ( ref[i]=='N' ) nN++;
+ if ( nN*2>i ) { free(aux); return -1; }
+
ks_introsort(uint32_t, m, aux);
// squeeze out identical types
for (i = 1, n_types = 1; i < m; ++i)
if (aux[i] != aux[i-1]) ++n_types;
- if (n_types == 1 || n_alt * MIN_SUPPORT_COEF < n_tot) { // no indels or too few supporting reads
- free(aux); return -1;
+ // Taking totals makes it hard to call rare indels
+ if ( !bca->per_sample_flt )
+ indel_support_ok = ( (float)n_alt / n_tot < bca->min_frac || n_alt < bca->min_support ) ? 0 : 1;
+ if ( n_types == 1 || !indel_support_ok ) { // then skip
+ free(aux); return -1;
+ }
+ if (n_types >= 64) {
+ free(aux);
+ if (bam_verbose >= 2)
+ fprintf(stderr, "[%s] excessive INDEL alleles at position %d. Skip the position.\n", __func__, pos + 1);
+ return -1;
}
types = (int*)calloc(n_types, sizeof(int));
t = 0;
for (t = 0; t < n_types; ++t)
if (types[t] == 0) break;
ref_type = t; // the index of the reference type (0)
- assert(n_types < 64);
}
{ // calculate left and right boundary
left = pos > INDEL_WINDOW_SIZE? pos - INDEL_WINDOW_SIZE : 0;
if (ref[i] == 0) break;
right = i;
}
+ /* The following block fixes a long-existing flaw in the INDEL
+ * calling model: the interference of nearby SNPs. However, it also
+ * reduces the power because sometimes, substitutions caused by
+ * indels are not distinguishable from true mutations. Multiple
+ * sequence realignment helps to increase the power.
+ *
+ * Masks mismatches present in at least 70% of the reads with 'N'.
+ */
+ { // construct per-sample consensus
+ int L = right - left + 1, max_i, max2_i;
+ uint32_t *cns, max, max2;
+ char *ref0, *r;
+ ref_sample = calloc(n, sizeof(void*));
+ cns = calloc(L, 4);
+ ref0 = calloc(L, 1);
+ for (i = 0; i < right - left; ++i)
+ ref0[i] = bam_nt16_table[(int)ref[i+left]];
+ for (s = 0; s < n; ++s) {
+ r = ref_sample[s] = calloc(L, 1);
+ memset(cns, 0, sizeof(int) * L);
+ // collect ref and non-ref counts
+ for (i = 0; i < n_plp[s]; ++i) {
+ bam_pileup1_t *p = plp[s] + i;
+ bam1_t *b = p->b;
+ uint32_t *cigar = bam1_cigar(b);
+ uint8_t *seq = bam1_seq(b);
+ int x = b->core.pos, y = 0;
+ for (k = 0; k < b->core.n_cigar; ++k) {
+ int op = cigar[k]&0xf;
+ int j, l = cigar[k]>>4;
+ if (op == BAM_CMATCH || op == BAM_CEQUAL || op == BAM_CDIFF) {
+ for (j = 0; j < l; ++j)
+ if (x + j >= left && x + j < right)
+ cns[x+j-left] += (bam1_seqi(seq, y+j) == ref0[x+j-left])? 1 : 0x10000;
+ x += l; y += l;
+ } else if (op == BAM_CDEL || op == BAM_CREF_SKIP) x += l;
+ else if (op == BAM_CINS || op == BAM_CSOFT_CLIP) y += l;
+ }
+ }
+ // determine the consensus
+ for (i = 0; i < right - left; ++i) r[i] = ref0[i];
+ max = max2 = 0; max_i = max2_i = -1;
+ for (i = 0; i < right - left; ++i) {
+ if (cns[i]>>16 >= max>>16) max2 = max, max2_i = max_i, max = cns[i], max_i = i;
+ else if (cns[i]>>16 >= max2>>16) max2 = cns[i], max2_i = i;
+ }
+ if ((double)(max&0xffff) / ((max&0xffff) + (max>>16)) >= 0.7) max_i = -1;
+ if ((double)(max2&0xffff) / ((max2&0xffff) + (max2>>16)) >= 0.7) max2_i = -1;
+ if (max_i >= 0) r[max_i] = 15;
+ if (max2_i >= 0) r[max2_i] = 15;
+ //for (i = 0; i < right - left; ++i) fputc("=ACMGRSVTWYHKDBN"[(int)r[i]], stderr); fputc('\n', stderr);
+ }
+ free(ref0); free(cns);
+ }
{ // the length of the homopolymer run around the current position
int c = bam_nt16_table[(int)ref[pos + 1]];
if (c == 15) l_run = 1;
}
}
// construct the consensus sequence
- max_ins = types[n_types - 1]; // max_ins is at least 0
+ max_ins = types[n_types - 1]; // max_ins is at least 0
if (max_ins > 0) {
- int *inscns_aux = calloc(4 * n_types * max_ins, sizeof(int));
+ int *inscns_aux = calloc(5 * n_types * max_ins, sizeof(int));
// count the number of occurrences of each base at each position for each type of insertion
for (t = 0; t < n_types; ++t) {
if (types[t] > 0) {
uint8_t *seq = bam1_seq(p->b);
for (k = 1; k <= p->indel; ++k) {
int c = bam_nt16_nt4_table[bam1_seqi(seq, p->qpos + k)];
- if (c < 4) ++inscns_aux[(t*max_ins+(k-1))*4 + c];
+ assert(c<5);
+ ++inscns_aux[(t*max_ins+(k-1))*5 + c];
}
}
}
inscns = calloc(n_types * max_ins, 1);
for (t = 0; t < n_types; ++t) {
for (j = 0; j < types[t]; ++j) {
- int max = 0, max_k = -1, *ia = &inscns_aux[(t*max_ins+j)*4];
- for (k = 0; k < 4; ++k)
+ int max = 0, max_k = -1, *ia = &inscns_aux[(t*max_ins+j)*5];
+ for (k = 0; k < 5; ++k)
if (ia[k] > max)
max = ia[k], max_k = k;
inscns[t*max_ins + j] = max? max_k : 4;
+ if ( max_k==4 ) { types[t] = 0; break; } // discard insertions which contain N's
}
}
free(inscns_aux);
else ir = est_indelreg(pos, ref, -types[t], 0);
if (ir > bca->indelreg) bca->indelreg = ir;
// fprintf(stderr, "%d, %d, %d\n", pos, types[t], ir);
- // write ref2
- for (k = 0, j = left; j <= pos; ++j)
- ref2[k++] = bam_nt16_nt4_table[bam_nt16_table[(int)ref[j]]];
- if (types[t] <= 0) j += -types[t];
- else for (l = 0; l < types[t]; ++l)
- ref2[k++] = inscns[t*max_ins + l];
- if (types[0] < 0) { // mask deleted sequences to avoid a particular error in the model.
- int jj, tmp = types[t] >= 0? -types[0] : -types[0] + types[t];
- for (jj = 0; jj < tmp && j < right && ref[j]; ++jj, ++j)
- ref2[k++] = 4;
- }
- for (; j < right && ref[j]; ++j)
- ref2[k++] = bam_nt16_nt4_table[bam_nt16_table[(int)ref[j]]];
- for (; k < max_ref2; ++k) ref2[k] = 4;
- if (j < right) right = j;
- // align each read to ref2
+ // realignment
for (s = K = 0; s < n; ++s) {
+ // write ref2
+ for (k = 0, j = left; j <= pos; ++j)
+ ref2[k++] = bam_nt16_nt4_table[(int)ref_sample[s][j-left]];
+ if (types[t] <= 0) j += -types[t];
+ else for (l = 0; l < types[t]; ++l)
+ ref2[k++] = inscns[t*max_ins + l];
+ for (; j < right && ref[j]; ++j)
+ ref2[k++] = bam_nt16_nt4_table[(int)ref_sample[s][j-left]];
+ for (; k < max_ref2; ++k) ref2[k] = 4;
+ if (j < right) right = j;
+ // align each read to ref2
for (i = 0; i < n_plp[s]; ++i, ++K) {
bam_pileup1_t *p = plp[s] + i;
- int qbeg, qend, tbeg, tend, sc;
+ int qbeg, qend, tbeg, tend, sc, kk;
uint8_t *seq = bam1_seq(p->b);
+ uint32_t *cigar = bam1_cigar(p->b);
+ if (p->b->core.flag&4) continue; // unmapped reads
+ // FIXME: the following loop should be better moved outside; nonetheless, realignment should be much slower anyway.
+ for (kk = 0; kk < p->b->core.n_cigar; ++kk)
+ if ((cigar[kk]&BAM_CIGAR_MASK) == BAM_CREF_SKIP) break;
+ if (kk < p->b->core.n_cigar) continue;
// FIXME: the following skips soft clips, but using them may be more sensitive.
// determine the start and end of sequences for alignment
qbeg = tpos2qpos(&p->b->core, bam1_cigar(p->b), left, 0, &tbeg);
indelQ2 = tmp > 111? 0 : (int)((1. - tmp/111.) * indelQ2 + .499);
// pick the smaller between indelQ1 and indelQ2
indelQ = indelQ1 < indelQ2? indelQ1 : indelQ2;
- p->aux = (sc[0]&0x3f)<<16 | seqQ<<8 | indelQ;
+ if (indelQ > 255) indelQ = 255;
+ if (seqQ > 255) seqQ = 255;
+ p->aux = (sc[0]&0x3f)<<16 | seqQ<<8 | indelQ; // use 22 bits in total
sumq[sc[0]&0x3f] += indelQ < seqQ? indelQ : seqQ;
-// fprintf(stderr, "pos=%d read=%d:%d name=%s call=%d q=%d\n", pos, s, i, bam1_qname(p->b), types[sc[0]&0x3f], indelQ);
+// fprintf(stderr, "pos=%d read=%d:%d name=%s call=%d indelQ=%d seqQ=%d\n", pos, s, i, bam1_qname(p->b), types[sc[0]&0x3f], indelQ, seqQ);
}
}
// determine bca->indel_types[] and bca->inscns
}
free(score1); free(score2);
// free
+ for (i = 0; i < n; ++i) free(ref_sample[i]);
+ free(ref_sample);
free(types); free(inscns);
return n_alt > 0? 0 : -1;
}
projects / rsem.git / blobdiff