We have identified a major bug in ReduceReads -- GATK versions 2.0 and 2.1. The effect of the bug is that variant regions with more than 100 reads and fewer than 250 reads get downsampled to 0 reads.

This has now been fixed in the most recent release.

To check if you are using a buggy version, run the following:

    samtools view -H $BAM

This will produce the following output:

    @PG ID:GATK ReduceReads VN:XXX

If XXX is 2.0 or 2.1, any results obtained with your current version are suspect, and you will need to upgrade to the most recent version then rerun your processing.

Our most sincere apologies for the inconvenience.

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@hoffsbeefs Yes, multithreading can explain some marginal differences. For purely deterministic behavior, it should be disabled.
25 Oct 16
@hoffsbeefs Yes it should be deterministic, given same data, same parameters and no multithreading.
25 Oct 16
RT @BroadGenomics: Missed #GATK WKSP at #ASHG16? 10am meet Geraldine at booth 329 - Broad’s GATK Guru @gatk_dev #BroadGenomicsExperts https…
20 Oct 16
RT @NJL_NGS: Broad Institute Workbench workshop now at #ashg16. https://t.co/t6L452mp8a
19 Oct 16
RT @konradjk: We're rebranding a bit! gnomAD now adds WGS regions, as well as doubling the data depth and increasing diversity (5K ASJ!) #A…
19 Oct 16

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Had a really nice time in Vancouver at #ASHG16, also known as "The @dgmacarthur Lab Meeting"
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Asked a question, speaker jokes not to edit your BAM header and expect GATK to let you get away with it.
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My new hobby: finding incomprehensible diagrams on office whiteboards and adding alarming conclusions to them https://t.co/7RAzBF0kYh
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I've easily written my first custom ReadFilter for GATK. The @gatk_dev 's toolkit is a great example of programming.
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