PGx: ClinPGx variant-based genes (PGX-008) and --guideline dpwg (PGX-025)

- fetch_sources.sh downloads ClinPGx clinicalVariants (CC BY-SA 4.0); pgx db build adds genotype-only
  variant-based genes (levels 1A-2B, level 3 for the parity list), rsIDs resolved from the manifest's probes:
  70 genes in the DB.
- pgx phenotype --guideline dpwg: CPIC mappings for CPIC genes (as ClinPGx curates DPWG), no phenotype for
  DPWG-only genes (flags dpwg_via_cpic_mapping / dpwg_mapping_not_available). K-029 updated.

docs/known_unknowns.md

@@ -4,7 +4,7 @@ Plan §20 lists the open questions; this file records what the implementation ha
 
 | ID | Date | Topic | Finding | Status |
 |---|---|---|---|---|
-| K-029 | 2026-09-29 | PGx star alleles (v2) | (1) PGX-012 error model: ε(GS) = 0.5·(1 − GS)² was replaced by ε = 1e-3 (GS ≥ 0.15) / 0.05 — after probe masking 0 of 9 740 GSA v4 PGx calls disagreed with 1000G 30x at any GS, and the old model made correct low-GS calls lose to the prior (spec amended). (2) PGX-010 masks derived from 14 individuals (spec: ≥ 100); a variant absent from the filtered 1000G panel counts as hom-ref only if rare (CYP2B6 rs2279343 is filtered out, not absent). (3) CPIC core-allele definitions use IUPAC wildcards; alleles without definitions (NUDT15 *2, structural CYP2D6) are not callable from SNVs. (4) GeT-RM uses legacy UGT1A1/SLCO1B1 names. Result vs GeT-RM (16 CEPH): 100/109 gene calls, CYP2D6/2C19/2C9 41/45. | Open: hybrids, G6PD/variant-based genes, PharmVar genes, phenotypes; larger/independent truth (`docs/validation/V2_pgx_star.md`). |
+| K-029 | 2026-09-29 | PGx star alleles (v2) | (1) PGX-012 error model: ε(GS) = 0.5·(1 − GS)² was replaced by ε = 1e-3 (GS ≥ 0.15) / 0.05 — after probe masking 0 of 9 740 GSA v4 PGx calls disagreed with 1000G 30x at any GS, and the old model made correct low-GS calls lose to the prior (spec amended). (2) PGX-010 masks derived from 14 individuals (spec: ≥ 100); a variant absent from the filtered 1000G panel counts as hom-ref only if rare (CYP2B6 rs2279343 is filtered out, not absent). (3) CPIC core-allele definitions use IUPAC wildcards; alleles without definitions (NUDT15 *2, structural CYP2D6) are not callable from SNVs. (4) GeT-RM uses legacy UGT1A1/SLCO1B1 names. Result vs GeT-RM (16 CEPH): 100/109 gene calls, CYP2D6/2C19/2C9 41/45. (5) DPWG: no public machine-readable genotype→phenotype mapping; CPIC mappings are used for genes CPIC covers (as ClinPGx does), DPWG-only genes (CYP1A2, CYP3A4, F5) get no phenotype. (6) GeT-RM definitions are older than CPIC/PharmVar for UGT1A1, SLCO1B1, CYP1A2 and CYP2C8 (e.g. PharmVar CYP2C8 *19 = rs2071426 alone). Result vs GeT-RM (16 CEPH, 21 genes): 154/168 comparable gene calls. | Open: larger/independent truth set; KNMP DPWG tables if they become available (`docs/validation/V2_pgx_star.md`). |
 | K-028 | 2026-09-29 | PGx CN (v2) | Deviations from PCN-009: the per-probe reference is the training cohort's median stored in the model (a calling-batch median is not CN 2 where deletions are common, e.g. GSTM1 null ≈ 50 %); no GC-correction step; the CN mixture is ours: µ_c = δ + γ·log2((c+1)/3) per region with a free lower CN-0 component and Hardy–Weinberg-constrained weights (probe compression differs by region: γ ≈ 0.19 CYP2D6.p5 … 0.56 GSTT1). Interim validation on the GSA v4 PGx demo — whose 36 arrays turned out to be 30 CEPH/1000G individuals — against NYGC 30x SV RD_CN: 224/240 region calls (GSTM1, UGT2B17 30/30), but in-sample (trained on the same arrays, < 96 samples, priors chosen with this truth in view). | Open: validate on an independent GSA-PGx cohort; CYP2D6 via GeT-RM star alleles (`docs/validation/V2_pgx_cn.md`). |
 | K-027 | 2026-09-29 | CN/LOH (v2) | CYTO-014 noise gate: the summary `logr_dev` also measures cluster-file mismatch (GSE165845: 0.246, all samples `SampleQuality`) while the LRR used after the batch reference has SD ≈ 0.1; the gate now uses the SD of the normalised LRR (the JSON still reports the summary value). Spec: built-in mask/cytobands from UCSC; the annotation bundle uses UCSC ncbiRefSeq instead of RefSeq GFF + Ensembl GTF + HGNC. Real-data result: constitutional DEL/DUP calls 74–77 % in NYGC truth, mosaic calls mostly false positives. Pi tuning: mosaic prior / switch distance barely matter; CYTO-041 (noise-normalised BAF split, complete-loss promotion) cuts PASS mosaic calls by ~30 % without losing implanted ≥ 15 % mosaics. Two limits remain: (1) without phasing, < 20 % mosaic losses are not separable from regional BAF noise; (2) common CNVs (carrier frequency > 20 %) are almost never detected (1/236 DEL) because the median-LRR batch reference absorbs them; rare DEL (< 5 %) 38 %. | Open: rare-event sensitivity as primary metric; phasing-based mosaic BAF (`docs/validation/V2_cn.md`). |
 | K-026 | 2026-09-29 | Methylation QC (v2) | Spec deviations: vendor EPIC manifests put a 5th field on some control lines (≥ 4 fields accepted); detection p follows sesame's pOOBAH (1 − max(F(M), F(U))) rather than the ambiguous "1 − ECDF(M + U)"; minfi-style `Sentrix_ID`/`Sentrix_Position` sheet keys accepted. Against sesame 1.28.1 on minfiDataEPIC: β r = 0.99998 (max \|Δβ\| 0.011), detection calls 99.1 % identical, noob signals within 0.5 % (median) / 5 % (max). The systematic remainder is unexplained; it is not the negative controls (sesame did not attach the supplied control table). | Open; `docs/validation/V2_methylation.md`. Next step: dump sesame's background vectors and noob parameters to find the difference. |