Extraction of SNPs from the 1000G vcf file for a set of regions

Question

[SGMS]

Hi all,

I am trying to extract SNPs from the vcf file of the 1000G using bcftools. I managed to extract the SNPs in a separate file, but I want to get the SNPs only in the regions which I'm interested in. I found that -R option provides me with this but I tried it in several ways and I didn't make it work. So the following works:

bcftools query -f'%CHROM\t%POS\t%REF,%ALT\n' ALL.wgs.phase3_shapeit2_mvncall_integrated_v5b.20130502.sites.vcf.gz > extraction.txt

But then the following does not:

bcftools query -f'%CHROM\t%POS\t%ID\t%REF,%ALT\n' -R regions.bed ALL.wgs.phase3_shapeit2_mvncall_integrated_v5b.20130502.sites.vcf.gz > extraction.txt

I'm suspecting that the problem is the bed file which initially was a .txt file. The original format was:

1:150748683-150800917
1:151758546-151824348
1:154520256-154572353

and now:

1:150718683-150830917   150718682       150830917
1:151728546-151854348   151728545       151854348
1:154490256-154602353   154490255       154602353

If someone could give me a hint, that would be great.

Thank you!

[trausch]

Try tab-delimited chrom, start, end and possibly identifier.

1   150718682       150830917 1:150718683-150830917
1   151728545       151854348 1:151728546-151854348
1   154490255       154602353 1:154490256-154602353

[venu]

Did you look at tabix?

Usage:   tabix [OPTIONS] [FILE] [REGION [...]]
tabix -h file.vcf.gz 1:150718683-150830917

Loop over a set of regions in your bed file.

[SGMS]

Sorry, I'm not sure whether I got this.. My initial file has the chr:start-end format and I don't know how to turn the bed file into a format accepted by bcftools..

[venu]

@StatGen Its not for bcftools solution. Its is for your entire task to create a new VCF file with a set of regions in bed file.

[SGMS]

Hi venu,

Thanks.. The task though is not to create a new vcf with a set of regions in a bed file.. I want to extract the SNPs from the 1000G vcf, whose positions overlap with the regions I will specify.. My regions though are in a text format which I turned into a bed format which is most probably not acceptable by the bcftools..

[venu]

Can you just show how you are expecting the output file?

[SGMS]

After I use bcftools I'm expecting:

1       10177   rs367896724     A,AC
1       10235   rs540431307     T,TA
1       10352   rs555500075     T,TA
1       10505   rs548419688     A,T
1       10506   rs568405545     C,G
1       10511   rs534229142     G,A

i.e CHR POS ID REF,ALT

Thanks

[venu]

tabix file.vcf.gz 1-10177-10177 | cut -f 1-5 > out.vcf

Select required fields with cut.