http://www.bioinf.jku.at/software/podkathttp://www.1000genomes.org/wiki/analysis/variant-call-format/vcf-variant-call-format-version-42
Li, H., Handsaker, B., Wysoker, A., Fenell, T., Ruan, J., Homer, N.,
Marth, G., Abecasis, G., Durbin, R., and 1000 Genome Project Data
Processing Subgroup (2009) The Sequence Alignment/Map format and
SAMtools. Bioinformatics 25, 2078-2079.