The mechanism-level artifact sentinels of the certified QC report: the oxoG sentinel share (C>A channel mass in the pyrimidine-normalized SBS96 space, where the damaged-strand G>T of oxoG reads) and the FFPE sentinel share (C>T deamination mass), each with its frozen house verdict clause spoken per mechanism – `gt_verdict` "hit" at `gt_share >= gt_share_flag` (the artifact clause of the certified `qc_flag`), `ct_verdict` "watch" at `ct_share >= ct_share_watch` (the watch clause), "na" for zero-total samples whose shares are NA. The overall `qc_flag` column is the certified report verdict itself.
Value
An `MsQcSentries` data.frame, one row per sample, columns in the frozen order `sample`, `gt_share`, `ct_share`, `gt_verdict`, `ct_verdict`, `qc_flag`.
References
Design memo `vignettes/articles/devlog-2026-10-04-M4-02b-qc-memo.qmd` section 1 (mechanism labels, verified against the Excerno/FFPEsig records) and section 3 (frozen shares and the declared flag constants). oxoG: Costello et al., NAR 2013 (doi:10.1093/nar/gks1443); FFPE deamination: Guo et al., Nat Commun 2022 (doi:10.1038/s41467-022-32041-5). Computation core `R/ms-qc-report.R` (.ms_qc_gt_channels, .ms_qc_ct_channels, .ms_qc_shares, .ms_qc_defaults, .ms_qc_flag).