Hi

I have a vcf file that looks like this:

4   169239903   M1  G   A   .   PASS    .   GT  0/0 1/1 1/1 1/1 1/1 1/1 1/1 1/1 ./. 1/1 1/1 1/1 1/1 1/1 ./. 1/1 1/0 1/1 1/1 ./.
4   169832919   M2  A   C   .   PASS    .   GT  0/0 ./. 1/1 1/1 ./. 1/1 1/1 1/1 1/1 1/1 1/1 1/1 1/1 ./. 1/1 ./. ./. 1/1 1/1 ./.
4   169989920   M3  C   T   .   PASS    .   GT  0/0 ./. ./. 1/1 1/1 1/1 1/1 1/1 1/1 1/1 1/1 1/1 1/1 1/1 ./. 1/1 ./. 1/1 ./. ./.

Now I will like to obtain a contex sequence with around 15 nucleotides upstream the SNP and 15 nucleotides downstream the SNP from the reference genome to have something like this:

>4_169239903
ATCCCGGTTCCCTCTgTTTCCTTTCCTTGCT
>4_169832919
ATCGTAGTTAGCTAAaTTTCGTACTGACTGA
>4_169989920
CGTGCTGCATGATCCcTTGGCAGTACGTACC

Do you known how to obtain it?

Thank you