Supplementary Figure S8. Myeloid cell transcriptional diversity in response to mutant-selective and broad spectrum RAS inhibitors.

Supplementary Figure S15. Clinical implications of mucinous lineage differentiation in human KRAS-mutant NSCLC cohorts

Supplementary Figure S3. Acute effects of active RAS inhibition in the KP2 and KL2 KrasG12C-mutant lung adenocarcinoma models

Supplementary Figure S10. MAPK pathway modulation in immune and stromal cell subsets in response to active RAS inhibition.

Supplementary Figure S4. Acute inhibition of active RAS in KRASG12C-mutant lung adenocarcinoma.

Linkage disequilibrium (LD) underpins mapping studies of Quantitative Trait Loci Regions (QTLRs). A common yet misled assumption assumes the closest sites to a significant marker as causative mutation candidates. We studied chicken LD of mapped chicken QTLRs for Marek’s Disease resistance in numerous populations and estimated background LD by random sampling of non-syntenic and syntenic marker pairs from different or same chromosomes. We defined LD blocks as marker groups located on the same chromosome having significant moderate (0.15 ≥ r2 < 0.7) or high (r2 ≥ 0.7) LD, regardless of distance and excluding mixed markers with no LD as a part of the block. We studied QTLR LD using SNP markers within the QTLRs. We found very complex LD patterns, with fragmented and interdigitated LD blocks. Exceptional high LD was found between two particular QTLRs, with shared protein networks suggesting possible functional relationships. Thus, causative candidates could be found beyond non-LD sites, occasionally at a very large distance from a significant marker, even in another QTLR. Multiple effects might make LD extremely complex, thus limiting GWAS informativity and repeatability. Complex LD challenges practical use across populations, and must be accounted for while interpreting genetic mapping studies.

Supplementary Figure S1. Activity of RAS inhibitors in immune-competent pre-clinical models of KRASG12C-mutated NSCLC.

Supplementary Figure S2. Models and mechanisms of acquired resistance to RAS inhibitors

Supplementary Figure S9. Stromal cell remodeling in response to RAS inhibition.

Supplementary Figure S11. Characterization of tumor-cell transcriptional heterogeneity following RAS inhibition.

Supplementary Table S2. Multivariate analyses.

Supplementary table S3. List of antibodies used for immunohistochemical studies.

Supplementary Figure S14. Mucinous tumor cells exhibit higher baseline expression of phospho-ERK1/2 and relative refractoriness to MAPK suppression following treatment with RMC-7977.

Supplementary Figure S6. Histological heterogeneity of lung tumors in the KrasG12C/+;Lkb1-/- GEM model.

Supplementary Figure S5. Active RAS inhibition in KrasG12C/+;Lkb1-/- GEMMs.

Supplementary Figure S13. Correlates of mucinous markers in human KRAS-mutant NSCLC

Supplementary Figure S7. Single-cell atlas of tumor infiltrating lymphoid cells in response to RAS inhibition.

Supplementary Table S9 shows datasets used for PK/Efficacy and PK/PD modeling.

The chicken is a valuable model for understanding fundamental biology and vertebrate evolution and is a major global source of nutrient-dense and lean protein. Despite being the first non-mammalian amniote to have its genome sequenced, a systematic characterization of functional variation on the chicken genome remains lacking. Here, we integrated bulk RNA sequencing (RNA-seq) data from 7,015 samples, single-cell RNA-seq data from 127,598 cells and 2,869 whole-genome sequences to present a pilot atlas of regulatory variants across 28 chicken tissues. This atlas reveals millions of regulatory effects on primary expression (protein-coding genes, long non-coding RNA and exons) and post-transcriptional modifications (alternative splicing and 3'-untranslated region alternative polyadenylation). We highlighted distinct molecular mechanisms underlying these regulatory variants, their context-dependent behavior and their utility in interpreting genome-wide associations for 39 chicken complex traits. Finally, our comparative analyses of gene regulation between chickens and mammals demonstrate how this resource can facilitate cross-species gene mapping of complex traits.

The discovery of elironrasib (RMC-6291) represents a significant breakthrough in targeting the previously deemed undruggable GTP-bound, active KRASG12C. To target the active state of RAS (RAS(ON)) directly, we have employed an innovative tri-complex inhibitor (TCI) modality involving formation of a complex with an inhibitor, the intracellular chaperone protein CypA, and the target protein KRASG12C in its GTP-bound form. The resulting tri-complex inhibits oncogenic signaling, inducing tumor regressions across various preclinical models of KRASG12C mutant human cancers. Here we report structure-guided medicinal chemistry efforts that led to the discovery of elironrasib, a potent, orally bioavailable, RAS(ON) G12C-selective, covalent, tri-complex inhibitor. The investigational agent elironrasib is currently undergoing phase 1 clinical trials (NCT05462717, NCT06128551, NCT06162221), with preliminary data indicating clinical activity in patients who had progressed on first-generation inactive state-selective KRASG12C inhibitors.