Understanding a VCF - Genotype likelihoods and genotype call
0
0
Entering edit mode
5.8 years ago
cetin.m ▴ 50

I calculated genotype likelihoods from a BAM file with the command: "samtools mpileup -g -f filename" and got the BCF file.

Then I used "bcftools call -c -v filename" to get the VCF.

In the VCF file, I see the following two:

1 589051 . G A 7.79993 . DP=1;SGB=-0.379885;MQ0F=0;AF1=1;AC1=2;DP4=0,0,1,0;MQ=37;FQ=-29.991 GT:PL 1/1:37,3,0

1 700436 . G A 4.77219 . DP=1;SGB=-0.379885;MQ0F=0;AF1=1;AC1=2;DP4=0,0,0,1;MQ=37;FQ=-29.9923 GT:PL 0/1:33,3,0

In the top SNP I get that the most likely genotype is 1/1 (given by the lowest Phred score of 0). Therefore the called genotype is 1/1.

However in the below one even though the loweest Phred score of 0 belongs to the 1/1 genotype, the called genotype is given by 0/1.

What am I missing?

I am new so this is probably obvious to many.

Thanks.

sequence sequencing next-gen • 2.0k views
ADD COMMENT
0
Entering edit mode

both variants doesn't mean much things: they both have only one read(DP=1) overlapping the variant....

ADD REPLY
0
Entering edit mode

I know. I am just trying to understand how the genotype likelihood part works.

Do you have a comment about that?

Thanks.

ADD REPLY

Login before adding your answer.

Traffic: 2526 users visited in the last hour
Help About
FAQ
Access RSS
API
Stats

Use of this site constitutes acceptance of our User Agreement and Privacy Policy.

Powered by the version 2.3.6