Problem:
Classes in com.sun.javadoc.* are non-standard. Since we can't depend on their availability for
all users, the GATK proper should not have any runtime dependencies on this package.
Solution:
-Isolate com.sun.javadoc.* dependencies in a DocletUtils class for use only by doclets. The
only users who need to run our doclets are those who compile from source, and they
should be competent enough to figure out how to resolve a missing com.sun.* dependency.
-HelpUtils now contains no com.sun.javadoc.* dependencies and can be safely used by walkers/other
tools.
-Added comments with instructions on when it is safe to use DocletUtils vs. HelpUtils
[delivers #51450385]
[delivers #50387199]
Problem:
-Downsamplers were treating reduced reads the same as normal reads,
with occasionally catastrophic results on variant calling when an
entire reduced read happened to get eliminated.
Solution:
-Since reduced reads lack the information we need to do position-based
downsampling on them, best available option for now is to simply
exempt all reduced reads from elimination during downsampling.
Details:
-Add generic capability of exempting items from elimination to
the Downsampler interface via new doNotDiscardItem() method.
Default inherited version of this method exempts all reduced reads
(or objects encapsulating reduced reads) from elimination.
-Switch from interfaces to abstract classes to facilitate this change,
and do some minor refactoring of the Downsampler interface (push
implementation of some methods into the abstract classes, improve
names of the confusing clear() and reset() methods).
-Rewrite TAROrderedReadCache. This class was incorrectly relying
on the ReservoirDownsampler to preserve the relative ordering of
items in some circumstances, which was behavior not guaranteed by
the API and only happened to work due to implementation details
which no longer apply. Restructured this class around the assumption
that the ReservoirDownsampler will not preserve relative ordering
at all.
-Add disclaimer to description of -dcov argument explaining that
coverage targets are approximate goals that will not always be
precisely met.
-Unit tests for all individual downsamplers to verify that reduced
reads are exempted from elimination
We now run Smith-Waterman on the dangling tail against the corresponding reference tail.
If we can generate a reasonable, low entropy alignment then we trigger the merge to the
reference path; otherwise we abort. Also, we put in a check for low-complexity of graphs
and don't let those pass through.
Added tests for this implementation that checks exact SW results and correct edges added.
Principle is simple: when coverage is deep enough, any single-base read error will look like a rare k-mer but correct sequence will be supported by many reads to correct sequences will look like common k-mers. So, algorithm has 3 main steps:
1. K-mer graph buildup.
For each read in an active region, a map from k-mers to the number of times they have been seen is built.
2. Building correction map.
All "rare" k-mers that are sparse (by default, seen only once), get mapped to k-mers that are good (by default, seen at least 20 times but this is a CL argument), and that lie within a given Hamming distance (by default, =1). This map can be empty (i.e. k-mers can be uncorrectable).
3. Correction proposal
For each constituent k-mer of each read, if this k-mer is rare and maps to a good k-mer, get differing base positions in k-mer and add these to a list of corrections for each base in each read. Then, correct read at positions where correction proposal is unanimous and non-empty.
The algorithm defaults are chosen to be very stringent and conservative in the correction: we only try to correct singleton k-mers, we only look for good k-mers lying at Hamming distance = 1 from them, and we only correct a base in read if all correction proposals are congruent.
By default, algorithm is disabled but can be enabled in HaplotypeCaller via the -readErrorCorrect CL option. However, at this point it's about 3x-10x more expensive so it needs to be optimized if it's to be used.
Ns are treated as wildcards in the PairHMM so creating haplotypes with Ns gives them artificial advantages over other ones.
This was the cause of at least one FN where there were Ns at a SNP position.
Problem:
The sequence graphs can get very complex and it's not enough just to test that any given read has non-unique kmers.
Reads with variants can have kmers that match unique regions of the reference, and this causes cycles in the final
sequence graph. Ultimately the problem is that kmers of 10/25 may not be large enough for these complex regions.
Solution:
We continue to try kmers of 10/25 but detect whether cycles exist; if so, we do not use them. If (and only if) we
can't get usable graphs from the 10/25 kmers, then we start iterating over larger kmers until we either can generate
a graph without cycles or attempt too many iterations.
-- Reuse infrastructure for RODs for reads to implement general IntervalReferenceOrderedView so that both TraverseReads and TraverseActiveRegions can use the same underlying infrastructure
-- TraverseActiveRegions now provides a meaningful RefMetaDataTracker to ActiveRegionWalker.map
-- Cleanup misc. code as it came up
-- Resolves GSA-808: Write general utility code to do rsID allele matching, hook up to UG and HC
-- Variants will be considered matching if they have the same reference allele and at least 1 common alternative allele. This matching algorithm determines how rsID are added back into the VariantContext we want to annotate, and as well determining the overlap FLAG attribute field.
-- Updated VariantAnnotator and VariantsToVCF to use this class, removing its old stale implementation
-- Added unit tests for this VariantOverlapAnnotator class
-- Removed GATKVCFUtils.rsIDOfFirstRealVariant as this is now better to use VariantOverlapAnnotator
-- Now requires strict allele matching, without any option to just use site annotation.
The previous behavior is to process reads with N CIGAR operators as they are despite that many of the tools do not actually support such operator and results become unpredictible.
Now if the there is some read with the N operator, the engine returns a user exception. The error message indicates what is the problem (including the offending read and mapping position) and give a couple of alternatives that the user can take in order to move forward:
a) ask for those reads to be filtered out (with --filter_reads_with_N_cigar or -filterRNC)
b) keep them in as before (with -U ALLOW_N_CIGAR_READS or -U ALL)
Notice that (b) does not have any effect if (a) is enacted; i.e. filtering overrides ignoring.
Implementation:
* Added filterReadsWithMCigar argument to MalformedReadFilter with the corresponding changes in the code to get it to work.
* Added ALLOW_N_CIGAR_READS unsafe flag so that N cigar containing reads can be processed as they are if that is what the user wants.
* Added ReadFilterTest class commont parent for ReadFilter test cases.
* Refactor ReadGroupBlackListFilterUnitTest to extend ReadFilterTest and push up some functionality to that class.
* Modified MalformedReadFilterUnitTest to extend ReadFilterTest and to test the new filter functionality.
* Added AllowNCigarMalformedReadFilterUnittest to check on the behavior when the unsafe ALLOW_N_CIGAR_READS flag is used.
* Added UnsafeNCigarMalformedReadFilterUnittest to check on the behavior when the unsafe ALL flag is used.
* Updated a broken test case in UnifiedGenotyperIntegrationTest resulting from the new behavior.
* Updated EngineFeaturesIntegrationTest testdata to be compliant with new behavior
- Memoized MathUtil's cumulative binomial probability function.
- Reduced the default size of the read name map in reduced reads and handle its resets more efficiently.
-- Created a new annotation DepthPerSampleHC that is by default on in the HaplotypeCaller
-- The depth for the HC is the sum of the informative alleles at this site. It's not perfect (as we cannot differentiate between reads that align over the event but aren't informative vs. those that aren't even close) but it's a pretty good proxy and it matches with the AD field (i.e., sum(AD) = DP).
-- Update MD5s
-- delivers [#48240601]
-- In the case where we have multiple potential alternative alleles *and* we weren't calling all of them (so that n potential values < n called) we could end up trimming the alleles down which would result in the mismatch between the PerReadAlleleLikelihoodMap alleles and the VariantContext trimmed alleles.
-- Fixed by doing two things (1) moving the trimming code after the annotation call and (2) updating AD annotation to check that the alleles in the VariantContext and the PerReadAlleleLikelihoodMap are concordant, which will stop us from degenerating in the future.
-- delivers [#50897077]
-- This occurred because we were reverting reads with soft clips that would produce reads with negative (or 0) alignment starts. From such reads we could end up with adaptor starts that were negative and that would ultimately produce the "Only one of refStart or refStop must be < 0, not both" error in the FragmentUtils merging code (which would revert and adaptor clip reads).
-- We now hard clip away bases soft clipped reverted bases that fall before the 1-based contig start in revertSoftClippedBases.
-- Replace buggy cigarFromString with proper SAM-JDK call TextCigarCodec.getSingleton().decode(cigarString)
-- Added unit tests for reverting soft clipped bases that create a read before the contig
-- [delivers #50892431]
-- Ultimately this was caused by overly aggressive merging of CommonSuffixMerger. In the case where you have this graph:
ACT [ref source] -> C
G -> ACT -> C
we would merge into
G -> ACT -> C
which would linearlize into
GACTC
Causing us to add bases to the reference source node that couldn't be recovered. The solution was to ensure that CommonSuffixMerger only operates when all nodes to be merged aren't source nodes themselves.
-- Added a convenient argument to the haplotype caller (captureAssemblyFailureBAM) that will write out the exact reads to a BAM file that went into a failed assembly run (going to a file called AssemblyFailure.BAM). This can be used to rerun the haplotype caller to produce the exact error, which can be hard in regions of deep coverage where the downsampler state determines the exact reads going into assembly and therefore makes running with a sub-interval not reproduce the error
-- Did some misc. cleanup of code while debugging
-- [delivers #50917729]
-- Ultimately this was caused by an underlying bug in the reverting of soft clipped bases in the read clipper. The read clipper would fail to properly set the alignment start for reads that were 100% clipped before reverting, such as 10H2S5H => 10H2M5H. This has been fixed and unit tested.
-- Update 1 ReduceReads MD5, which was due to cases where we were clipping away all of the MATCH part of the read, leaving a cigar like 50H11S and the revert soft clips was failing to properly revert the bases.
-- delivers #50655421
-- Although the original bug report was about SplitSamFile it actually was an engine wide error. The two places in the that provide compression to the BAM write now check the validity of the compress argument via a static method in ReadUtils
-- delivers #49531009