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PubMed2026

T-Cell Leukemia Cell Line Harboring Previously Undescribed CBFB::MYL11 Fusion Exhibits a Genome Profile Implicating Cytoskeletal Abnormality.

INTRODUCTION: Gene fusions involving core binding factors (CBFs), such as CBFB::MYH11, are major contributing factors to leukemia development. The pathogenic mechanism is believed to lie in abnormalities in CBF, however, myosin, the fusion partner, has received little attention. In a preliminary analysis, we identified a previously undescribed fusion transcript, CBFB::MYL11, in RNA-sequencing data from the T-cell leukemia cell line HPB-ALL. We hypothesized that leukemia cells harboring CBFB::MYH11 or CBFB::MYL11 may share a common pathological mechanism involving myosin fusion. METHODS: Fluorescence in situ hybridization was performed to analyze the structure of CBFB::MYL11 and Western blotting was performed to verify the fusion protein in HPB-ALL. Differentially expressed gene (DEG) and gene ontology (GO) analyses were performed on ME-1 harboring CBFB::MYH11 and HPB-ALL to investigate characteristics of gene expression and molecular function. RESULTS: In situ amplification of MYL11 and co-amplification of CBFB and MYL11 on a marker chromosome were observed. Elevated MYH11 and MYL11 expression and significant upregulation of genes related to the cytoskeleton were observed in the ME-1 and HPB-ALL cell lines. Bands consistent with the CBFB::MYL11 fusion protein were observed using Western blotting. CONCLUSION: This study underscores the pathological significance of cytoskeletal abnormalities in leukemia with CBFB/myosin fusion and provides a foundation for further investigation into their molecular mechanisms.

Journal Article↗
PubMed2026

Expanding the genetic landscape of SLC4A1-linked hereditary spherocytosis: discovery of a novel TM9 variant using high-resolution genomic profiling analysis.

INTRODUCTION: Hereditary spherocytosis (HS) is the most common inherited red cell membranopathy caused by defects in erythrocyte membrane and cytoskeletal proteins, including ankyrin, spectrin, band 3, and protein 4.2. Among these, mutations in SLC4A1, which encodes the erythrocyte anion exchanger band 3 (AE1), account for approximately 20-30% of HS cases and it is associated with distal renal tubular acidosis (dRTA), reflecting phenotypic and functional heterogeneity. METHODS: In this study, seven unrelated Indian patients with clinically suspected HS were investigated using detailed hematological, biochemical, and clinical evaluations along with eosin-5'-maleimide (EMA) binding assays. Molecular analysis was performed using targeted next-generation sequencing (t-NGS) covering 81 genes associated with red cell disorders, and the identified SLC4A1 variants were validated by Sanger sequencing. The structural and functional consequences of the variants were assessed through in silico tools including DynaMut, PolyPhen-2, and SIFT. RESULTS: Seven SLC4A1 variants were identified, including six previously reported variants and one novel variant, p.Phe702Ser, detected in heterozygous or compound heterozygous states. These variants were distributed across both cytoplasmic and transmembrane domains of the band 3 protein. Most patients presented with mild to moderate HS characterized by anemia, jaundice, splenomegaly, reticulocytosis, and reduced EMA fluorescence. One patient harboring compound heterozygous variants (p.Arg490His and p.Ala858Asp) exhibited HS associated with dRTA, highlighting the functional diversity of SLC4A1 mutations. The novel p.Phe702Ser variant, located in the transmembrane domain TM9, was predicted to destabilize AE1 structure and potentially impair anion transport. DISCUSSION: Marked intrafamilial phenotypic variability was observed despite identical genotypes. These findings expand the mutational spectrum of SLC4A1-related HS in Indian patients.

SLC4A1↗
PubMed2026

Comprehensive Genomic Profiling Reveals the Mutational Spectrum and Clinical Significance of BRCA1/2 and Other Cancer-Susceptibility Genes in Breast Cancer Patients from Southern Tunisia.

BACKGROUND/OBJECTIVES: This study aims to investigate the mutational spectrum of BRCA1 and BRCA2 genes in a cohort of breast cancer (BC) patients from southern Tunisia, and to evaluate their clinical and prognostic significance. Additionally, this study explores the contribution of other cancer predisposition genes and the prevalence of variants of uncertain significance (VUS). RESULTS: Among the 165 patients included, pathogenic or likely pathogenic variants (P/LPVs) in BRCA1/BRCA2 were identified in 19 cases (11.51%), including 8 in BRCA1 and 11 in BRCA2. The presence of BRCA P/LPVs associated with young patients (p = 0.006) and those with TNBC (p = 0.036). Beyond BRCA1/2, PV/LPVs were detected in other cancer-related genes, including TP53 (n = 3), CHEK2, RAD50 (n = 2 cases each), and MUTYH, BARD1, and BRIP1 (one case each). Furthermore, 56 VUS were identified; among them, 7 were prioritized based on in silico predictive analyses, suggesting a potential deleterious effect. However, these VUS should not be used for clinical decision-making without additional evidence from functional and familial segregation studies. CONCLUSIONS: Our findings provide novel insights into the genetic landscape of breast cancer in southern Tunisia, highlighting the clinical relevance of BRCA1/2 mutations and the contribution of other susceptibility genes. These results support the personalized management of breast cancer patients and the implementation of expanded multigene panel testing in routine clinical practice to improve genetic counseling.

BRCA1↗
PubMed2026

Age as a core disease modifier: Distinct clinical, molecular and prognostic landscapes of essential thrombocythaemia in adolescents and young adults.

Essential thrombocythaemia (ET) in adolescents and young adults (AYA, 15-39 years) is a distinct entity with an incompletely defined prognosis. In this multicentre retrospective study, 1728 ET patients from 29 centres across China were stratified into AYA (n = 328) and non-AYA (≥40 years, n = 1400) cohorts. We compared their clinical profiles, genomic landscapes, long-term outcomes and risk factors for progression to post-ET myelofibrosis (MF). AYA patients had fewer cardiovascular risks and lower thrombosis rates, but higher rates of extreme thrombocytosis. Molecularly, AYA patients were enriched for calreticulin (CALR) mutations, whereas Janus kinase 2 (JAK2) predominated in older patients. The burden of non-driver mutations (tet methylcytosine dioxygenase 2 [TET2], DNA methyltransferase 3A [DNMT3A], ASXL transcriptional regulator 1 [ASXL1], SH2‑B adaptor protein 3 [SH2B3]) was lower in AYA patients. Consequently, AYA patients achieved superior long-term outcomes across all key survival endpoints, including overall, myelofibrosis-free and leukaemia-free survival. Analysis of post-ET MF progression risks identified age-specific patterns: CALR mutations are enriched in younger patients and show an age-specific association with MF progression. AYA-ET constitutes a unique clinicomolecular subtype with a favourable prognosis, supporting age-stratified management. The enrichment of CALR mutations and their specific link to MF progression in young patients underscore the urgent need for targeted therapies against CALR-mutant clones.

adolescents and young adults (AYA)↗
PubMed2025

Genome-Wide Profiling of Histone Modifications in Fission Yeast Using CUT&Tag.

Eukaryotic DNA is organized in the nucleus in the form of chromatin. Nucleosomes, the fundamental unit of chromatin, are subject to many posttranslational modifications (PTMs) as well as compositional variations through incorporation of histone variants. These alterations play important roles in regulation of genome structure and activity. Genome-wide profiling of these regulatory features is essential for understanding of genome function. Chromatin immunoprecipitation coupled with next-generation sequencing (ChIP-Seq) is a widely used method to assay genome-wide localization in fission yeast but suffers from the requirement for a large amount of input chromatin, antibodies, and a cumbersome experimental pipeline. New methods such as Cleavage Under Targets and Tagmentation (CUT&Tag), which combine the specificity of targeted cleavage and adapter insertion with the sensitivity of next-generation sequencing, enable identification and characterization of various epigenetic marks affording low input requirement as well as more streamlined protocols. However, these approaches have not been adapted for use in fission yeast, Schizosaccharomyces pombe. Here, we describe an adapted CUT&Tag protocol for epigenomic profiling in fission yeast using the heterochromatin-associated histone H3K9 methylation PTM for benchmarking.

Schizosaccharomyces↗
PubMed2026

Tumor Mutational Landscape and Its Correlation With Histopathological Characteristics in Breast Cancer.

BACKGROUND/AIM: In breast cancer, knowledge of the associations between clinicopathologic characteristics, genetic changes, and subtype-specific patterns is expanding. This study investigated how pathological and clinical variables affect the actionability of Next Generation Sequencing (NGS)-based tumor molecular data. MATERIALS AND METHODS: 227 breast cancer patients referred to Genekor's laboratory for tumor molecular profile analysis were included in the study. Pathology records were used to assess critical clinicopathological features, including HER2, ER, PR, Ki67, grade, metastatic site, and age. A 1021-gene NGS-based multigene panel was utilized to assess tumor biology alongside tumor mutational burden (TMB) and microsatellite instability (MSI). RESULTS: Comprehensive genomic profiling revealed that 95.6% of the patients harbored at least one oncogenic or likely oncogenic alteration, highlighting the high diagnostic yield of NGS-based testing. Distinct subtype-specific patterns were observed: HR+/HER2- tumors were enriched for PIK3CA and ESR1 gene alterations, whereas triple-negative breast cancer (TNBC) was dominated by TP53 alterations. Clinically actionable alterations were most common in HR+/HER2- tumors (~60% on-label), whereas TNBC more often harbored off-label or trial-associated targets. The inclusion of tumor-agnostic biomarkers (TMB/MSI) increased on-label actionability up to 64.5% in HR+/HER2- tumors, primarily driven by TMB-high cases. Median TMB values were low, and age was the only independent predictor. Furthermore, the presence of actionable alterations was significantly higher in metastatic tumors, and TP53 alterations were associated with aggressive tumor characteristics. CONCLUSION: Comprehensive NGS-based genomic profiling identifies clinically actionable alterations in over half of breast cancer patients, with substantial variability across molecular subtypes. The HR+/HER2- subtype demonstrates the highest prevalence of on-label actionable biomarkers. These findings support the routine implementation of comprehensive genomic profiling, especially in metastatic HER2-negative breast cancer, to guide precision oncology strategies and enable enrollment in biomarker-driven clinical trials.

Humans↗
PubMed2025

Genome-wide profiling the integration patterns with T7-PCR.

Integration of exogenous gene fragments into the host genomes is a widely used and powerful method for studying gene functions, advancing molecular breeding, and conducting gene therapy. Accurately identifying the integration sites is essential for ensuring both the safety and efficacy of genome engineering efforts. However, current mapping techniques are constrained by high costs and a low signal-to-noise ratio. In this study, we developed an innovative tool for mapping integration sites, leveraging T7 polymerase-mediated in vitro transcription (T7-IVT) to capture the junction fragments surrounding integration loci. This approach converts genomic flanking sequences into RNA, enabling the simultaneous enrichment of junction fragments and the elimination of background genomic DNA, thereby significantly enhancing the signal-to-noise ratio. We have validated the efficiency of this method, named T7-PCR, across yeast, plant, and human cells under diverse integration scenarios. T7-PCR outperforms current next-generation sequencing (NGS)-based mapping strategies in terms of efficiency and accuracy, with minimal positional effects. This method is highly applicable for high-throughput transgene screening and also supports the development of next-generation tools for targeted integration of large fragments.

Humans↗
PubMed2026

Age- and sex-adjusted genomic differences between Korean and Beat AML cohorts.

Genomic profiling plays a central role in risk stratification and therapeutic decision-making in acute myeloid leukemia (AML), yet the clinical implications of population-specific genomic architectures remain incompletely defined. We conducted a prospective, multicenter study of 603 adults with newly diagnosed AML in Korea, integrating targeted sequencing of 83 recurrently mutated genes with comprehensive clinical annotation across treatment intensities, including allogeneic hematopoietic stem cell transplantation (allo-HSCT). For contextual comparison, genomic profiles were evaluated against the Beat AML cohort. The overall genomic landscape was broadly conserved, supporting shared core disease biology across populations. However, RUNX1::RUNX1T1, CEBPA, GATA2, KIT, and DDX41 mutations were more frequent in the Korean cohort, whereas FLT3 and NPM1 mutations were less common. These differences translated into a distinct distribution of European LeukemiaNet (ELN) 2022 risk categories, with implications for therapeutic stratification. Notably, most DDX41 alterations were germline (3.2%), highlighting the need for systematic germline evaluation with implications for genetic counseling and donor selection. Although unadjusted overall survival appeared longer in the Korean cohort, this difference was not significant after adjustment for key clinical variables. These findings indicate that population-specific genomic distributions reshape the clinical application of risk stratification and support population-aware precision medicine strategies in AML.

Journal Article↗
PubMed2026

Genome-wide profiling of histone modifications and transcription factor binding at single-cell resolution by DeChIC-seq.

Mapping of protein-DNA interactions at single-cell resolution remains a central challenge in epigenomics, particularly for transcription factors (TFs), whose sparse binding limits reliable detection. Here, we establish DeChIC-seq (DNA Deaminase-based Chromatin Immuno-Conversion sequencing), a conversion-based strategy that uses a protein A-DddAtox fusion to directly record protein-DNA interactions by inducing localized C-to-U conversions near antibody-bound chromatin. Retaining genome-wide background sequence information without immunoprecipitation, DeChIC-seq enables profiling of histone modifications and sensitive detection of TF binding. Integration with single-cell whole-genome amplification extends DeChIC-seq to single-cell applications (scDeChIC-seq), enabling chromatin profiling of individual cells. Applied to mouse embryogenesis, scDeChIC-seq resolves lineage-specific chromatin states through profiling of H3K4me3, CTCF, and RAD21 and sensitively detects TF binding, including that of NR5A2, TFAP2C, and KLF5, from extremely limited blastomere inputs. This underscores its strong potential for detecting TF-binding sites in scarce biological samples. DeChIC-seq establishes a conversion-based framework for chromatin profiling that enables mechanistic dissection of TF-driven gene regulation across rare cells, developmental systems, and disease contexts.

Animals↗
PubMed2026

Cost-Effectiveness and the Economics of Genomic Testing and Molecularly Matched Therapies.

Cost-effectiveness analysis of precision oncology can help guide value-driven care. Next-generation sequencing is increasingly cost-efficient over single gene testing because diagnostic algorithms require multiple individual gene tests to determine biomarker status. Matched targeted therapy is often not cost-effective due to the high cost associated with drug treatment. However, genomic profiling can promote cost-effective care by identifying patients who are unlikely to benefit from therapy. Additional applications of genomic profiling such as universal testing for hereditary cancer syndromes and germline testing in patients with cancer may represent cost-effective approaches compared with traditional history-based diagnostic methods.

Humans↗
PubMed2026

Translational case series comparing next-generation sequencing profiles of primary breast cancer and brain metastases.

BACKGROUND: Breast cancer (BC) is a heterogeneous disease, and its molecular and immunohistochemical (IHC) profiles may change over time, particularly under therapeutic pressure. IHC discordance between primary tumors and BC brain metastases (BCBM) has been reported, yet its biological and clinical significance remains incompletely defined. Genomic profiling using next-generation sequencing (NGS) may provide additional insight into tumor evolution and clonal selection, although data from paired BC and BCBM are limited. METHODS: This translational case series included six patients randomly selected from an institutional cohort of BC patients who underwent neurosurgical resection of BCBM. IHC reassessment (ER, PR, and HER2) and NGS profiling using targeted panels were performed. RESULTS: Three of the six cases presented with IHC discordance, mainly loss of HR expression and gain of HER2 in BCBM. Genomic profiling identified 23 mutations in primary tumors compared with four in BCBM. BRCA1/2 variants predominated in primary tumors (21/23, 91%), most predicted to result in loss-of-function alterations. One mutation (PIK3CA/N345K) was shared between primary and metastatic tissues within the same patient. Overall survival ranged from 28 to 146 months. CONCLUSION: This paired analysis demonstrates immunophenotypic and genomic divergence between BC and BCBM, supporting the concept of dynamic tumor evolution. Receptor conversion and emergence or loss of actionable genomic alterations highlight the potential value of repeat molecular assessment in advanced stages. Although limited by a small sample size, retrospective design, and absence of matched germline testing, these findings reinforce the importance of integrating biomarker reevaluation into the management of selected patients.

Humans↗
PubMed2025

Q RadFusion: Hybrid Quantum Classical Radiogenomic Framework for Breast Cancer Diagnosis.

BACKGROUND AND PURPOSE: Breast cancer remains the most common cancer in women worldwide, with early and accurate diagnosis critical for patient survival. Radiogenomics integrates imaging phenotypes with genomic profiles, offering a pathway to precision diagnostics. However, existing classical machine learning models often struggle with the high dimensionality and heterogeneity of multimodal data, leading to issues in calibration and reproducibility. This study presents Q RadFusion, a hybrid quantum-classical framework designed to enhance breast cancer diagnosis by fusing mammography and genomics data. METHODS: Q RadFusion was implemented on two publicly available datasets: CBIS-DDSM (2,600 curated mammography cases, TCIA) and TCGA-BRCA (1,000 genomic profiles, GDC). Imaging preprocessing included bias-field correction, segmentation, and harmonization, while genomic data underwent normalization and imputation. Feature selection was performed using the Quantum Approximate Optimization Algorithm (QAOA), and features were mapped into a quantum Hilbert space using Variational Quantum Circuits (VQC). For multimodal fusion, ResNet encoded mammography features, and a Transformer encoded genomic features. Patient-level and site-held-out splits were used for evaluation. RESULTS: Q RadFusion achieved an AUC of 0.96 and accuracy of 94%, outperforming baselines including CNN-LSTM, ResNet + XGBoost, and multimodal Transformers. Ablation studies confirmed the contribution of quantum components, with optimal performance observed at circuit depth, qubits, and QAOA layers. The model also demonstrated improved calibration and ~ 80% fewer parameters compared to deep fusion networks. CONCLUSION: Q RadFusion demonstrates that hybrid quantum-classical radiogenomic integration can deliver accurate, reproducible, and clinically meaningful diagnostic support for breast cancer, with strong potential for future clinical translation.

Breast Cancer↗
PubMed2025

Small cell bladder carcinoma with a high tumor mutational burden responding to sequential cisplatin-etoposide and pembrolizumab: a case report.

Small cell carcinoma of the urinary bladder (SCCB) is a rare and aggressive malignancy with limited treatment options and a poor prognosis. We present the case of a 63-year-old man who was initially diagnosed to have non-metastatic high-grade non-muscle invasive urothelial carcinoma with sarcomatoid subtype and later developed bone metastases. A bone biopsy confirmed small cell carcinoma, and retrospective review of the original tumor revealed mixed histology comprising small cell, sarcomatoid-like, and conventional urothelial carcinoma components. The patient was treated with six cycles of cisplatin and etoposide, during which genomic profiling identified a high tumor mutational burden (22 mutations/megabase). Based on this finding, pembrolizumab was administered sequentially as monotherapy. The patient achieved a complete response that lasted for more than 1 year, but subsequently developed lymph node metastases and recurrences in bone. This case highlights the role of genomic profiling test for clinical decision-making as tumor mutational burden predicts the efficacy of immune checkpoint inhibitor therapy in SCCB. This case also underscores the urgent need for novel treatment approaches for SCCB.

Case report↗
PubMed2026

Futibatinib after non-covalent FGFR inhibitors in FGFR2-rearranged intrahepatic cholangiocarcinoma: clinical activity and resistance patterns.

PURPOSE: The optimal sequencing of non-covalent and covalent FGFR inhibitors in FGFR2-rearranged intrahepatic cholangiocarcinoma (iCCA) remains undefined. Futibatinib, an irreversible FGFR1-4 inhibitor, may retain activity in the setting of acquired resistance to non-covalent FGFR inhibitors, but data on the patterns of acquired alterations are limited. METHODS: We conducted a retrospective multicenter study across three European centers including patients with advanced FGFR2-rearranged iCCA treated with futibatinib after progression on non-covalent FGFR inhibitors. Clinical outcomes and safety were evaluated. Available genomic profiling at progression was analyzed to characterize resistance mechanisms and their association with outcomes. RESULTS: Sixteen patients were included. Median progression-free survival (mPFS) with prior non-covalent FGFR inhibitors was 10.2 months (95% CI 7.0-15.5), with an objective response rate (ORR) of 60.0%. Among patients with post-progression genomic profiling (n = 11), all harbored FGFR2 resistance mutations, with polyclonal alterations (≥2) in 45.5%. A higher burden of FGFR2 mutations and the presence of co-alterations were associated with shorter mPFS on non-covalent inhibitors. Futibatinib was administered at a median of fourth-line therapy. ORR was 31.3% and disease control rate was 50.0%. Median PFS and overall survival were 4.5 months (95% CI 2.0-9.1) and 9.9 months (95% CI 5.7-not reached), respectively. Notably, outcomes with futibatinib were independent of the number of acquired FGFR2 resistance mutations, and the adverse impact of co-alterations appeared attenuated. Safety was consistent with the known profile. CONCLUSIONS: Futibatinib demonstrates clinically meaningful activity after progression on non-covalent FGFR inhibitors, supporting its use in FGFR2-rearranged iCCA, including in the post-non-covalent inhibitor setting. The distinct resistance patterns provide a biological rationale for the continued efficacy of covalent FGFR inhibition. Prospective studies incorporating longitudinal molecular profiling are needed to optimize treatment sequencing.

Drug resistance↗
PubMed2026

Limitations of serial cloning in mammals: unresolved donor-cell genomic integrity challenges broad claims of cloning limits.

Wakayama et al. describe an extraordinary 20-year serial cloning study in mice, concluding that serial cloning in mammals is ultimately limited by the accumulation of genetic anomalies. However, their whole-genome sequencing (WGS) analysis characterized selected cloned animals but did not include matched genomic profiling of the corresponding cumulus cell (CC)-donor mice, the source CC populations, or developmental stages. Because each reconstructed embryo originated from a single CC nucleus and re-cloned animals were used to advance the lineage, pre-existing somatic variation could have entered the lineage and subsequently been propagated. Consequently, variants detected in later generations cannot be assigned definitively to pre-existing donor-cell mosaicism, donor-cell handling, somatic cell nuclear transfer manipulation, or early embryogenesis. Thus, the observed decline cannot be attributed exclusively to genetic lesions arising during repeated cloning, but the unresolved genomic status of the lineage-founding donor cells remains a plausible but unproven contributor. The study therefore demonstrates the transmission and propagation of genetic lesions through serial cloning more directly than it establishes that all initiating lesions arose because of repeated cloning. Paired genomic profiling of donor-cell populations, embryos, and offspring would help resolve the origins of accumulated genetic lesions and determine whether donor-cell screening could extend serial cloning.

Animals↗
PubMed2022

Profiling Genome-Wide DNA Methylation in Children with Autism Spectrum Disorder and in Children with Fragile X Syndrome.

Autism spectrum disorder (ASD) is an early onset, developmental disorder whose genetic cause is heterogeneous and complex. In total, 70% of ASD cases are due to an unknown etiology. Among the monogenic causes of ASD, fragile X syndrome (FXS) accounts for 2-4% of ASD cases, and 60% of individuals with FXS present with ASD. Epigenetic changes, specifically DNA methylation, which modulates gene expression levels, play a significant role in the pathogenesis of both disorders. Thus, in this study, using the Human Methylation EPIC Bead Chip, we examined the global DNA methylation profiles of biological samples derived from 57 age-matched male participants (2-6 years old), including 23 subjects with ASD, 23 subjects with FXS with ASD (FXSA) and 11 typical developing (TD) children. After controlling for technical variation and white blood cell composition, using the conservatory threshold of the false discovery rate (FDR ≤ 0.05), in the three comparison groups, TD vs. AD, TD vs. FXSA and ASD vs. FXSA, we identified 156, 79 and 3100 differentially methylated sites (DMS), and 14, 13 and 263 differential methylation regions (DMRs). Interestingly, several genes differentially methylated among the three groups were among those listed in the SFARI Gene database, including the PAK2, GTF2I and FOXP1 genes important for brain development. Further, enrichment analyses identified pathways involved in several functions, including synaptic plasticity. Our preliminary study identified a significant role of altered DNA methylation in the pathology of ASD and FXS, suggesting that the characterization of a DNA methylation signature may help to unravel the pathogenicity of FXS and ASD and may help the development of an improved diagnostic classification of children with ASD and FXSA. In addition, it may pave the way for developing therapeutic interventions that could reverse the altered methylome profile in children with neurodevelopmental disorders.

Child↗
PubMed2026

One chromatin, many structures: From ensemble contact maps to single-cell 3D organization.

Understanding how chromatin folds in three dimensions remains challenging because most experimental assays capture low-dimensional projections of an underlying, highly heterogeneous polymer. Here, we present an ensemble-based interpretive framework built on the previously introduced Self-Returning Excluded Volume (SR-EV) model, a minimal generator of chromatin conformations using a nucleosome-indexed coarse-grained representation based on stochastic return rules and excluded-volume geometry. Despite its simplicity, SR-EV recapitulates key experimental signatures across scales: heterogeneous nanoscale packing domains resembling ChromEMT and ChromSTEM observations, sparse and highly variable single-configuration contact patterns analogous to single-cell chromosome conformation capture (Hi-C), and robust ensemble-level contact enrichment consistent with topologically associating domains (TADs). In this framework, Hi-C loop and TAD signatures are interpreted as ensemble-level statistical enrichments rather than invariant features of single-cell conformations. SR-EV is explicitly designed to generate large ensembles of complete three-dimensional chromatin configurations that can be projected consistently onto two-dimensional contact maps and one-dimensional genomic profiles. By introducing architectural-protein effects only through ensemble selection rather than explicit forces, SR-EV supports a separation between intrinsic polymer geometry and regulatory bias and suggests that TAD-like features can emerge as statistical enrichments rather than deterministic three-dimensional structures. Coordination number and probe-based accessibility computed directly from SR-EV provide a unified link between three-dimensional packing, two-dimensional contact maps, and one-dimensional genomic profiles. The main contribution of this work is to show, within a single coarse-grained framework, how these multimodal observables arise as linked projections of the same heterogeneous chromatin ensemble through averaging and conditional sampling. Together, these results establish SR-EV as a minimal and geometrically grounded mesoscale reference framework for interpreting how heterogeneous chromatin ensembles give rise to multimodal experimental observables while remaining consistent with the fact that chromatin organization is realized in individual cells.

Chromatin↗