OverviewSummary analysis of a single pre-adapter artifact. These artifacts occur on the original template strand, before the addition of adapters, so they correlate with read number / orientation in a specific way. For example, the well-known "Oxo-G" artifact occurs when a G on the template strand is oxidized, giving it an affinity for binding to A rather than the usual C. Thus PCR will introduce apparent G>T substitutions in read 1 and C>A in read 2. In the resulting alignments, a given G>T or C>A observation could either be: 1. a true mutation 2. an OxoG artifact 3. some other kind of artifact On average, we assume that 1 and 3 will not display this read number / orientation bias, so their contributions will cancel out in the calculation.
GATK version 18.104.22.168-SNAPSHOT built at Wed, 13 Apr 2022 13:12:10 -0700.