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  • kakar_nipun
    Junior Member
    • Jul 2009
    • 3

    Calling indels from samtools-pileup

    Hi Guys

    I was not clear on the samtools indel calling documentation, and therefore wanted to clarify a few things. I observe the following cases in my samtools-indel calling output.

    chr10 215923 * +G/* 943 1614 59 84 +G * 1 83 0 0 0

    chr10 278061 * */+G 284 284 60 24 * +G 23 1 0 0 0

    chr10 257113 * +GCAAG/+GAC 266 1710 59 88 +GCAAG +GAC 1 1 86 11 26

    I am unable to understand the difference between the first and the second case; according to me both show an insertion of one base(G). However what i am not clear about is the difference between :+G/* and */+G.?

    Regarding the third case shown above, the question is kind of related to the above question. What does +GCAAG/+GAC mean?. Looking at the no. reads columns it seems,
    1 read saw +GCAAG
    1 read saw +GAC
    but, what is the third allele in this case, as there are 86 reads seeing some third allele.?
  • dnusol
    Senior Member
    • Jul 2009
    • 136

    #2
    Chech the SAM FAQ for samtools on page 2. There is no difference in the two results.

    To me, +GCAAG/+GAC seems to be that there could be a het insertion, but I cannot guess what the third allele value could indicate.

    HTH

    Comment

    • Gangcai
      Member
      • Nov 2009
      • 30

      #3
      Unclear about Indels calling in samtools pileup file

      Hi everyone,
      Has anybody solved the problem already? I also meet the same problem. In my case,
      I want to know if an Indel is homozygous or heterzygous. The pileup file(from Sanger SNP pileup file) looks like this:
      1 3000648 * -CTTACA/* 367 747 58 17 -CTTACA * 11 6 00 0

      1 3004544 * -C/-C 71 381 60 11 -C * 8 3 0 00

      My question is how does it look like for all the 17 and 11 reads mapped? Are all of them have such deletions?

      Originally posted by kakar_nipun View Post
      Hi Guys

      I was not clear on the samtools indel calling documentation, and therefore wanted to clarify a few things. I observe the following cases in my samtools-indel calling output.

      chr10 215923 * +G/* 943 1614 59 84 +G * 1 83 0 0 0

      chr10 278061 * */+G 284 284 60 24 * +G 23 1 0 0 0

      chr10 257113 * +GCAAG/+GAC 266 1710 59 88 +GCAAG +GAC 1 1 86 11 26

      I am unable to understand the difference between the first and the second case; according to me both show an insertion of one base(G). However what i am not clear about is the difference between :+G/* and */+G.?

      Regarding the third case shown above, the question is kind of related to the above question. What does +GCAAG/+GAC mean?. Looking at the no. reads columns it seems,
      1 read saw +GCAAG
      1 read saw +GAC
      but, what is the third allele in this case, as there are 86 reads seeing some third allele.?
      Last edited by Gangcai; 01-21-2011, 03:34 AM.

      Comment

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