Difference between revisions of "Variant classification"

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(Created page with "= Introduction = The Variant Call Format (VCF) is a flexible file format specification that allows us to represent many different variant types ranging from SNPs, indels to c...")
 
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= Definitions =
 
= Definitions =
  
The normalization of a variant representation in VCF consists of two parts: parsimony and left alignment pertaining to the nature of a variant's length and position respectively.  
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The normalization of a variant representation in VCF consists of two parts: parsimony and left alignment pertaining to the nature of a variant's length and position respectively.
  
 +
== Example ==
  
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 +
Summarizes the variants in a VCF file
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 +
<div class=" mw-collapsible mw-collapsed">
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  #summarizes the variants found in mills.vcf
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  vt peek mills.vcf
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 +
<div class="mw-collapsible-content">
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  usage : vt peek [options] <in.vcf>
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  options : -o  output VCF file [-]
 +
            -I  file containing list of intervals []
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            -i  intervals []
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            -r  reference sequence fasta file []
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            --  ignores the rest of the labeled arguments following this flag
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            -h  displays help
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</div>
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</div>
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#This is a sample output of a peek command which summarizes the variants found in a VCF file.
 +
  stats: no. of samples                    :          0
 +
          no. of chromosomes                :        22<br>
 +
          ========== Micro variants ==========<br>
 +
          no. of SNPs                        :  77228885
 +
              2 alleles (ts/tv)              :        77011302 (2.11) [52287790/24723512]
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              3 alleles (ts/tv)              :          216560 (0.75) [185520/247600]
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              4 alleles (ts/tv)              :            1023 (0.50) [1023/2046]<br>
 +
          no. of MNPs                        :          0
 +
              2 alleles (ts/tv)              :              0 (-nan) [0/0]
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              >=3 alleles (ts/tv)            :              0 (-nan) [0/0]<br>
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          no. Indels                        :    2147564
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              2 alleles (ins/del)            :        2124842 (0.47) [683250/1441592]
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              >=3 alleles (ins/del)          :          22722 (2.12) [32411/15286]<br>
 +
          no. SNP/MNP                        :          0
 +
              3 alleles (ts/tv)              :              0 (-nan) [0/0]
 +
              >=4 alleles (ts/tv)            :              0 (-nan) [0/0] <br>
 +
          no. SNP/Indels                    :      12913
 +
              2 alleles (ts/tv) (ins/del)    :            412 (0.41) [120/292] (3.68) [324/88]
 +
              >=3 alleles (ts/tv) (ins/del)  :          12501 (0.43) [7670/17649] (18.64) [12434/667]<br>
 +
          no. MNP/Indels                    :        153
 +
              2 alleles (ts/tv) (ins/del)    :              0 (-nan) [0/0] (-nan) [0/0]
 +
              >=3 alleles (ts/tv) (ins/del)  :            153 (0.30) [138/465] (0.27) [67/248]<br>
 +
          no. SNP/MNP/Indels                :          2
 +
              3 alleles (ts/tv) (ins/del)    :              0 (-nan) [0/0] (-nan) [0/0]
 +
              4 alleles (ts/tv) (ins/del)    :              2 (0.00) [3/5] (1.00) [3/3]
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              >=5 alleles (ts/tv) (ins/del)  :              0 (-nan) [0/0] (-nan) [0/0]<br>
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          no. of clumped variants            :      19025
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              2 alleles                      :              0 (-nan) [0/0] (-nan) [0/0]
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              3 alleles                      :          18508 (0.16) [12152/75366] (0.00) [93/18653]
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              4 alleles                      :            451 (0.15) [369/2390] (0.33) [201/609]
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              >=5 alleles                    :              66 (0.09) [37/414] (1.19) [107/90]<br>
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          ====== Other useful categories =====<br>
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          no. complex variants              :      32093
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              2 alleles (ts/tv) (ins/del)    :            412 (0.41) [120/292] (3.68) [324/88]
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              >=3 alleles (ts/tv) (ins/del)  :          31681 (0.21) [20369/96289] (0.64) [12905/20270]<br>
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          ======= Structural variants ========<br>
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          no. of structural variants        :      41217
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              2 alleles                      :          38079
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                  deletion                  :                13135
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                  insertion                  :                16451
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                    mobile element          :                    16253
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                        ALU                  :                        12513
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                        LINE1                :                        2911
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                        SVA                  :                          829
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                    numt                    :                      198
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                  duplication                :                  664
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                  inversion                  :                  100
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                  copy number variation      :                7729
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              >=3 alleles                    :            3138
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                  copy number variation      :                3138 <br>
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          ========= General summary ========== <br>
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          no. of reference                  :          0 <br>
 +
          no. of observed variants          :  79449759
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          no. of unclassified variants      :          0
  
 
= Maintained by =
 
= Maintained by =
  
 
This page is maintained by  [mailto:atks@umich.edu Adrian].
 
This page is maintained by  [mailto:atks@umich.edu Adrian].

Revision as of 10:13, 5 September 2014

Introduction

The Variant Call Format (VCF) is a flexible file format specification that allows us to represent many different variant types ranging from SNPs, indels to copy number variations. However, variant representation in VCF is non-unique for variants that have explicitly expressed reference and alternate sequences.

On this wiki page, we describe a a variant classification system for VCF variants.

Definitions

The normalization of a variant representation in VCF consists of two parts: parsimony and left alignment pertaining to the nature of a variant's length and position respectively.

Example

Summarizes the variants in a VCF file

  #summarizes the variants found in mills.vcf
  vt peek mills.vcf
 usage : vt peek [options] <in.vcf>
 options : -o  output VCF file [-]
           -I  file containing list of intervals []
           -i  intervals []
           -r  reference sequence fasta file []
           --  ignores the rest of the labeled arguments following this flag
           -h  displays help
#This is a sample output of a peek command which summarizes the variants found in a VCF file.
  stats: no. of samples                     :          0
         no. of chromosomes                 :         22
========== Micro variants ==========
no. of SNPs : 77228885 2 alleles (ts/tv) : 77011302 (2.11) [52287790/24723512] 3 alleles (ts/tv) : 216560 (0.75) [185520/247600] 4 alleles (ts/tv) : 1023 (0.50) [1023/2046]
no. of MNPs : 0 2 alleles (ts/tv) : 0 (-nan) [0/0] >=3 alleles (ts/tv) : 0 (-nan) [0/0]
no. Indels : 2147564 2 alleles (ins/del) : 2124842 (0.47) [683250/1441592] >=3 alleles (ins/del) : 22722 (2.12) [32411/15286]
no. SNP/MNP : 0 3 alleles (ts/tv) : 0 (-nan) [0/0] >=4 alleles (ts/tv) : 0 (-nan) [0/0]
no. SNP/Indels : 12913 2 alleles (ts/tv) (ins/del) : 412 (0.41) [120/292] (3.68) [324/88] >=3 alleles (ts/tv) (ins/del) : 12501 (0.43) [7670/17649] (18.64) [12434/667]
no. MNP/Indels : 153 2 alleles (ts/tv) (ins/del) : 0 (-nan) [0/0] (-nan) [0/0] >=3 alleles (ts/tv) (ins/del) : 153 (0.30) [138/465] (0.27) [67/248]
no. SNP/MNP/Indels : 2 3 alleles (ts/tv) (ins/del) : 0 (-nan) [0/0] (-nan) [0/0] 4 alleles (ts/tv) (ins/del) : 2 (0.00) [3/5] (1.00) [3/3] >=5 alleles (ts/tv) (ins/del) : 0 (-nan) [0/0] (-nan) [0/0]
no. of clumped variants : 19025 2 alleles : 0 (-nan) [0/0] (-nan) [0/0] 3 alleles : 18508 (0.16) [12152/75366] (0.00) [93/18653] 4 alleles : 451 (0.15) [369/2390] (0.33) [201/609] >=5 alleles : 66 (0.09) [37/414] (1.19) [107/90]
====== Other useful categories =====
no. complex variants : 32093 2 alleles (ts/tv) (ins/del) : 412 (0.41) [120/292] (3.68) [324/88] >=3 alleles (ts/tv) (ins/del) : 31681 (0.21) [20369/96289] (0.64) [12905/20270]
======= Structural variants ========
no. of structural variants : 41217 2 alleles : 38079 deletion : 13135 insertion : 16451 mobile element : 16253 ALU : 12513 LINE1 : 2911 SVA : 829 numt : 198 duplication : 664 inversion : 100 copy number variation : 7729 >=3 alleles : 3138 copy number variation : 3138
========= General summary ==========
no. of reference : 0
no. of observed variants : 79449759 no. of unclassified variants : 0

Maintained by

This page is maintained by Adrian.