Test-drive the GATK tools and Best Practices pipelines on Terra
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CombineVariants and allele frequency
I recenltly ran -T CombineVariants on a set of samples and I noticed that the allele frequency (AF) in the info field changed. In the individual VCF, AF=0.3 for the particular variant I was looking at, however, after I combined multiple VCFs, AF=0.5.... however the variant was only seen in the one sample, so how could the frequency change?
Any insight is appreciated.