vcf (5) - Linux Manuals

vcf: Variant Call Format

NAME

vcf - Variant Call Format

DESCRIPTION

The Variant Call Format (VCF) is a TAB-delimited format with each data line consisting of the following fields:
   CHROMCHROMosome name
   POSthe left-most POSition of the variant
   IDunique variant IDentifier
   REFthe REFerence allele
   ALTthe ALTernate allele(s) (comma-separated)
   QUALvariant/reference QUALity
   FILTERFILTERs applied
   INFOINFOrmation related to the variant (semicolon-separated)
   FORMATFORMAT of the genotype fields (optional; colon-separated)
10+    SAMPLESAMPLE genotypes and per-sample information (optional)

The following table gives the INFO tags used by samtools and bcftools.

AF1
Max-likelihood estimate of the site allele frequency (AF) of the first ALT allele (double)
DP
Raw read depth (without quality filtering) (int)
DP4
# high-quality reference forward bases, ref reverse, alternate for and alt rev bases (int[4])
FQ
Consensus quality. Positive: sample genotypes different; negative: otherwise (int)
MQ
Root-Mean-Square mapping quality of covering reads (int)
PC2
Phred probability of AF in group1 samples being larger (,smaller) than in group2 (int[2])
PCHI2
Posterior weighted chi^2 P-value between group1 and group2 samples (double)
PV4
P-value for strand bias, baseQ bias, mapQ bias and tail distance bias (double[4])
QCHI2
Phred-scaled PCHI2 (int)
RP
# permutations yielding a smaller PCHI2 (int)
CLR
Phred log ratio of genotype likelihoods with and without the trio/pair constraint (int)
UGT
Most probable genotype configuration without the trio constraint (string)
CGT
Most probable configuration with the trio constraint (string)
VDB
Tests variant positions within reads. Intended for filtering RNA-seq artifacts around splice sites (float)
RPB
Mann-Whitney rank-sum test for tail distance bias (float)
HWE
Hardy-Weinberg equilibrium test (Wigginton et al) (float)

SEE ALSO

https://github.com/samtools/hts-specs
The full VCF/BCF file format specification
A note on exact tests of Hardy-Weinberg equilibrium
Wigginton JE et al PMID:15789306