PubMed HealthSearch

SEARCH · PubMed Health

Results for “INDEL Mutation”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources

Duplex-Indel: a Snakemake pipeline for somatic Indel calling in Tn5 transposase-based duplex sequencing data.

SUMMARY: Duplex-Indel is a novel Snakemake workflow for detecting somatic small insertions and deletions (Indels) from Tn5 transposase-based duplex sequencing data. Duplex-Indel enhances the accuracy of mutation calling at the single-molecule level by requiring consensus support from both DNA strands for each somatic Indel, minimizing confounding from technical artifacts. Duplex-Indel extends somatic mutation calling in Tn5 transposase-based duplex sequencing data to include Indels. We have demonstrated the accuracy and robustness of Duplex-Indel using cancer cell lines. AVAILABILITY AND IMPLEMENTATION: Source code and documentation are available under the MIT license on GitHub at https://github.com/ealee-lab/duplex-indel and archived on Zenodo at https://doi.org/10.5281/zenodo.19228799.

Transposases

IMPACT OF FLUORESCENT DYES ON MUTATIONS IN NEXT GENERATION SEQUENCING LIBRARY GENERATION.

DNA labelling fluorescent dyes such as ethidium bromide have long been considered to be highly mutagenic during DNA replication. While recent studies have pushed back on this narrative, the intercalative nature of these dyes continues to raise the possibility that these dyes can induce mutations. The iconPCR instrument by n6tec uses fluorescent dyes to measure amplification in real time and to adjust cycling conditions. However, since this use of qPCR is preparative and not analytical, mutations introduced by fluorescent dyes would be propagated into the sequencing reaction. To address the impact of these dyes on downstream analyses, we have performed routine mutation calling as well as mutational signature analysis on samples amplified using the iconPCR in the presence of either SYBR or EvaGreen. Sequence analysis revealed very minimal impacts of dyes on the reactions, largely within the noise regimen with only subtle changes in mutation rates seen. Mutational signature analysis was unable to identify any key signatures assignable to the dyes in either substitutions or indel domains. The mutational impact of intercalating dyes during fluorescence-guided amplification is therefore minimal and can be disregarded in all but the most sensitive NGS applications.

Fluorescent Dyes

Inflammation and mutational burden differentially associated with nivolumab or ipilimumab combination efficacy in colorectal cancer.

Nivolumab alone and in combination with ipilimumab demonstrated durable clinical benefit in patients with previously treated microsatellite instability-high/mismatch repair-deficient metastatic colorectal cancer in the phase 2 CheckMate 142 study. Here, we report exploratory biomarker analyses from CheckMate 142 evaluating associations between various tissue biomarkers and the efficacy of nivolumab monotherapy and nivolumab plus ipilimumab combination in these patients. Higher expression of inflammation-related gene expression signatures is associated with improved response per investigator assessment and survival benefit with nivolumab monotherapy. In contrast, higher tumor mutational burden, tumor indel burden, and degrees of microsatellite instability are associated with improved response per investigator assessment and survival benefit with nivolumab plus ipilimumab. While interpretation is limited by the exploratory nature of these analyses, they suggest that tumor antigenicity rather than baseline tumor inflammation might be important for the combinatorial efficacy. Validation of these findings in larger, randomized studies is necessary.

Humans

Rat somatic genome editing enables ER+ breast cancer modeling.

Genetically engineered mouse models have advanced cancer research but often fail to capture key features of certain human tumors. Rats, with distinct physiology and tumor biology, offer a powerful alternative, yet their use has been constrained by technical barriers to genome editing. Here, we report efficient somatic genome editing in rats, enabling both Indel and substitution mutations. We then apply this approach to model estrogen receptor (ER)-positive breast cancer, which accounts for ~70% of human cases but remains poorly represented in mice. The resulting rat tumors reproduce hallmarks of human ER+ breast cancer, including ductal histology, hormone responsiveness, and immune-microenvironmental features. By contrast, identical genetic alterations in mice failed to yield ER+ tumors, underscoring critical species differences in tumorigenesis. Together, this work establishes a versatile platform for rapid generation of clinically relevant rat tumor models, opening new avenues to dissect tumor biology, therapeutic response, and immune interactions in previously inaccessible cancer subtypes.

Journal Article

Enhanced exonuclease-Cas9 systems promote multiple nucleotide deletions with higher efficiency and broader targeting scope in plants.

CRISPR-Cas9 is a widely used platform for plant genome editing, but its outcomes are typically dominated by small insertions and deletions (indels). Such limited mutation profiles restrict its utility in functional studies of non-coding RNAs and regulatory elements, such as microRNAs (miRNAs), untranslated regions (UTRs), and promoter sequences, where larger sequence disruptions are often required. Here, we developed enhanced exonuclease-Cas9 platforms, termed multiple nucleotide deletion Cas9 (MND-Cas9) systems, for efficient generation of large deletions in rice. By screening four exonucleases (RecJ, T5, TREX2, and SbcB), we established MND-Cas9v1 systems based on TREX2 or SbcB that produced substantially larger deletions without reducing editing efficiency. Further optimization with an inserted DNA-binding domain (DBD) between Cas9 and exonuclease yielded MND-Cas9v2, which simultaneously enhanced efficiency and deletion size. To expand PAM compatibility, we introduced PAM-relaxed Cas9-NG and SpG variants, generating MND-Cas9-NG/SpGv2 systems with broader targeting scope and superior performance compared to their parental nucleases. Finally, we demonstrated the utility of these systems in two applications: MND-Cas9v2 efficiently knocked out the miRNA gene OsMIR530, producing larger seeds, and generated extended deletions in the 3'UTR of OsGhd2, which upregulated its expression and increased grain size. These results demonstrate that MND-Cas9 systems enable high-efficiency generation of extended deletions and facilitate functional analyses of non-coding RNAs and regulatory sequences. Overall, this work establishes a versatile and expandable exonuclease-Cas9 platform that substantially broadens the mutational spectrum and application potential of CRISPR-Cas9 for plant genome engineering.

CRISPR-Cas Systems

Co-occurrence of bronchiolar adenoma and lung adenocarcinoma: a study of nine cases revealing distinct clonal origins via integrated histologic, immunophenotypic and molecular analysis.

PURPOSE: This study sought to elucidate the possible biological association between BA and lung adenocarcinoma through an analysis of cases in which both lesions coexist within the same specimen. METHODS: In our cohort, the BA and lung cancer components of nine concurrent-type BAs were microdissected using the Millisect system and subjected to whole-exome sequencing (WES). Their histopathological, immunohistochemical, and genomic profiles were comparatively evaluated. RESULTS: Histopathologically, the BA regions of concurrent-type BAs exhibited a classic bilayered architecture, composed of continuous luminal and basal cell layers. The adjacent monolayered concurrent components were diagnosed as adenocarcinoma in situ (AIS, N = 4), minimally invasive adenocarcinoma (MIA, N = 2), and invasive adenocarcinoma (ADC, N = 3). Immunohistochemically, both luminal and basal cells in BA regions expressed thyroid transcription factor 1 (TTF1), albeit with more heterogeneous staining intensity compared to that observed in tumor components. Molecularly, EGFR mutations were the most frequently identified in either BA or tumor components, or in both (Case 9). In BA components, mutations included exon 19 p.S752F, exon 19 deletions (p.L747_T751delinsP and p.E746_T751delinsVP), and compound G719C/S768I mutations. Tumor components harbored exon 28 S1130C, exon 19 indel (p.E746_S752delins), and exon 18 p.G719C mutations. Notably, only three cases demonstrated limited overlap of mutations and copy number variations (CNVs) between the two components. Phylogenetic analysis revealed that six cases shared truncal alterations in genes including KMT2A, PIK3CA, SETD2, MITF, PBRM1, and SRSF3, one case harbored a shared canonical EGFR mutation (p.G719C), with an additional p.S768I alteration uniquely detected in the BA component. CONCLUSION: There is insufficient evidence to support BA as a premalignant lesion for lung adenocarcinoma base on morphological and molecular variables, and they may represent distinct pathological entities.

Concurrent-type bronchiolar adenoma

Lineage-associated small inversions disrupt dosT, dnaE2, and a promoter-adjacent region in some Mycobacterium tuberculosis isolates.

UNLABELLED: Large molecular inversions in the genome of Mycobacterium tuberculosis (Mtb) due to factors like the presence of insertion sequences and transposases are widely known. However, smaller inversions within coding sequences and non-coding control elements are rarely reported. The present study aims to identify inversions and their potential impact on Mtb biology in a lineage-specific manner. Structural variants (SVs) could only be detected by long reads. For this, we simulated long reads by de novo assembling the short-read sequencing data sets and subsequently aligned representative strains from each lineage using the Progressive Mauve algorithm. Independently, long-read sequencing from the Pacific Biosciences platform was acquired and analyzed using the structural variant identification method. Variants were merged, and Fisher's exact test was carried out to identify the inversion association with lineages. To visualize deoxyribonucleic acid (DNA) features, the DNA-features-viewer tool was used. Simulated reads from short-read sequencing gave indications of lineage (L)-specific inversions. The long-read sequencing approach led to the identification of seven unique inversions: two positively associated with L1, one positively associated with L3, two negatively associated with L4, and two positively associated with L3 but negatively associated with L4 (P < 0.05). The inversions encompassed primarily non-essential genes like sdaA, dosT, Rv2026c, dnaE2, Rv1341, Rv1342, and lprD. An interesting inversion was observed in the upstream control element of purB and Rv0776c. The study sheds light on small inversions that may be causing alterations in expression, formation of fusion genes, and nonsense mutations that may have a role in lineage-specific phenotypic changes. IMPORTANCE: The role of mutations like SNPs and INDELs and their association with drug resistance is well known in Mycobacterium tuberculosis (Mtb). However, structural variations, especially inversions, are largely overlooked and unreported. In this paper, publicly available whole-genome sequencing datasets from Illumina and Pacific Biosciences-Oxford Nanopore Technologies platform have been used to detect inversions and report seven unreported Mtb lineage-specific small inversions.

Mycobacterium tuberculosis

Discovering human transcription factor physical interactions with genetic variants, novel DNA motifs, and repetitive elements using enhanced yeast one-hybrid assays.

Identifying transcription factor (TF) binding to noncoding variants, uncharacterized DNA motifs, and repetitive genomic elements has been technically and computationally challenging. Current experimental methods, such as chromatin immunoprecipitation, generally test one TF at a time, and computational motif algorithms often lead to false-positive and -negative predictions. To address these limitations, we developed an experimental approach based on enhanced yeast one-hybrid assays. The first variation of this approach interrogates the binding of >1000 human TFs to repetitive DNA elements, while the second evaluates TF binding to single nucleotide variants, short insertions and deletions (indels), and novel DNA motifs. Using this approach, we detected the binding of 75 TFs, including several nuclear hormone receptors and ETS factors, to the highly repetitive Alu elements. Further, we identified cancer-associated changes in TF binding, including gain of interactions involving ETS TFs and loss of interactions involving KLF TFs to different mutations in the TERT promoter, and gain of a MYB interaction with an 18-bp indel in the TAL1 superenhancer. Additionally, we identified TFs that bind to three uncharacterized DNA motifs identified in DNase footprinting assays. We anticipate that these enhanced yeast one-hybrid approaches will expand our capabilities to study genetic variation and undercharacterized genomic regions.

Algorithms

Mutation accumulation in a hybrid parthenogenetic vertebrate.

Asexual lineages are thought to experience elevated extinction rates compared with sexual species, yet direct evidence for the underlying genetic causes remains scarce. Muller's ratchet predicts that the absence of recombination in asexual organisms facilitates the accumulation of deleterious mutations, thereby reducing long-term fitness. Here, we test this hypothesis in the hybrid-origin, parthenogenetic whiptail lizard Aspidoscelis tesselatus by integrating short-read RNAseq and long-read IsoSeq data from both the asexual lineage and its parental sexual species. We reconstructed phased transcripts for A. tesselatus to quantify mutation accumulation relative to the parental sexual species. Comparative analyses revealed elevated &#x3c9; ratios in both parental genomic complements (subgenomes) of the parthenogenetic lineage, consistent with accelerated accumulation of nonsynonymous mutations. Structural variant analyses identified multiple indels in expressed transcripts predicted to disrupt protein domains. Functional annotation indicated that genes affected by both single-nucleotide variants and indels were enriched for roles in chromatin organization, apoptosis regulation, and transcriptional control. While both parental subgenomes showed similar evolutionary patterns, the maternal complement exhibited more structural and missense mutations than the paternal complement. Together, these results provide evidence that mutations accumulate in asexual A. tesselatus in genes involved in core cellular functions, supporting theoretical predictions that Muller's ratchet contributes to mutation accumulation in asexual lineages.

Animals

Targeted multiplex gene knockouts in Lemna minor using CRISPR/Cas9.

Lemna minor (commonly known as duckweed) is a fast-growing aquatic plant recognized as a promising green bioreactor for recombinant protein production. Its rapid proliferation, high protein yield, environmental adaptability, and edibility make it highly attractive for biotechnological applications. It is essential to develop and expand genetic tools tailored to this species to maximize these advantages and further unlock its biotechnological potential. A key strategy for achieving this goal is the implementation of advanced genome editing technologies, such as the CRISPR/Cas9 system. Although multiplex CRISPR/Cas9 gene editing has previously been successfully applied in Lemna aequinoctialis, the capability of the endogenous plant tRNA processing system for multiplex editing in L. minor using the polycistronic tRNA-sgRNA (PTG)/Cas9 system has not yet been explored. In this study, a PTG construct was engineered to include four sgRNAs designed to simultaneously target two plant-specific glycosyltransferase genes: &#x3b1;-1,3-fucosyltransferase (FucT) and &#x3b2;-1,2-xylosyltransferase (XylT). As anticipated, the PTG-Cas9 system successfully induced frameshift mutations, characterized by insertions and deletions (indels), in regenerated L. minor plants derived from transformed calli. Validation via PCR and RT-PCR analysis, followed by sequencing of the target loci, confirmed the presence of indels at the target sites. Furthermore, western blot analyses utilizing antibodies specific to XylT and FucT in two homozygous lines (lines 44 and 217) revealed truncated XylT proteins in both lines. Moreover, an in-frame FucT protein was detected in line 217, whereas FucT expression was absent in line 44. This study marked the first successful demonstration of PTG-Cas9 system for multiplex genome editing in L. minor, paving the way for advanced genetic engineering in this species.

CRISPR-Cas Systems

The shape of fitness functions and the distribution of mutational effect sizes jointly limit adaptation by regulatory mutations.

Mutations in gene regulatory regions have been shown to play a role in rapid adaptation, but the factors determining their contribution are largely unknown. Here, using the metabolic enzyme cytosine deaminase of budding yeast, we examine whether adaptation to 5-fluorocytosine, which requires reduced cytosine deamination and can readily arise from amino acid substitutions, may be reached by single promoter mutations. We generated all single-nucleotide substitutions and indels in the FCY1 promoter and assayed the resulting mutants in presence of 5-fluorocytosine. This revealed that no promoter mutation is sufficient for adaptation to occur. We next investigated how this inaccessibility of adaptation arises by combining large-scale expression measurements with the experimental characterization of the corresponding expression-fitness function. These experiments showed that the shape of this function precludes single promoter mutations from being adaptive. Although 24% of mutations significantly affect expression, the fitness curve is flat around wild-type level. As such, adaptation can only emerge from a severe reduction of expression, which cannot occur from a single mutation in the promoter. Our results show that the contribution of regulatory mutations to rapid adaptation depends not only on the distribution of mutational effect sizes on expression level but also on the shape of the function linking fitness to expression levels.

Promoter Regions, Genetic

Incorporating indel channels into average-case analysis of seed-chain-extend.

MOTIVATION: Given a sequence s1 of n letters drawn independently and identically (i.i.d.) from an alphabet of size &#x3c3; and a mutated substring s2 of length m<n, we want to recover the mutation history that generated s2 from s1. Many modern sequence aligners for this task use seed-chain-extend with k-mer seeds. Previously, Shaw and Yu showed linear-gap cost chaining can produce a chain with 1-O(1m) recoverability, the proportion of the mutation history that is recovered, in O(mn2.43&#x3b8;&#x2009;log&#x2009;n) expected time for seed-chain-extend (assuming pre-seeded reference), where &#x3b8;<0.206 is the mutation rate under a substitution-only channel and s1 is uniformly random. A gap remains between theory and practice, as real genomes include insertions and deletions (indels). RESULTS: We introduce mathematical machinery to deal with the two new obstacles introduced by indel channels: the dependence of neighbouring anchors and the presence of anchors that are only partially correct. We prove that expected recoverability of an optimal chain is &#x2265;1-O(1m) and expected runtime is O(mn3.15&#xb7;&#x3b8;T&#x2009;log&#x2009;n), given the total mutation rate &#x3b8;T=&#x3b8;i+&#x3b8;d+&#x3b8;s (sum of substitution, insertion, and deletion rates) is &#x3b8;T&#x2264;0.159. We thus narrow (but not close) the gap between theory and practice. AVAILABILITY AND IMPLEMENTATION: https://github.com/Lazarus42/seed_chainer_indels.

INDEL Mutation

Comparisons Between Large-Scale Genomic Variants and SNPs in Driving Population Divergence and Local Adaptation.

Genomic variations, such as indels (2-49 bp) and structural variants (SVs, &#x2265;50 bp), are larger-scale mutations than single nucleotide polymorphisms (SNPs) and can substantially impact evolutionary processes, including speciation, adaptation, and phenotypes. Despite their functional importance, integrative population genetic analyses that jointly consider genome-wide SNPs, indels, and SVs remain under-explored. The ground tit (Pseudopodoces humilis), an endemic species to the Qinghai-Tibet Plateau (QTP), exhibits divergence across distinct glacial refugia, accompanied by habitat and morphological divergence, making it an excellent example for investigating how different types of genomic variants contribute to population divergence and local adaptation. Here, by retrieving 81 whole-genome sequence data, over 13 million SNPs, 2 million indels, and 22,101 SVs were identified. Variants were unevenly distributed across the genome, characterized by distinct hotspot regions. Indels and SVs revealed four genetic clusters consistent with previous SNP-based results, thereby validating the reliability of our variant datasets. FST and genotype-environment association (GEA) analyses independently revealed numerous candidate indels and SVs; each showed minimal overlap with previously identified SNPs, and were enriched in similar functional pathways such as signal transduction, skeletal muscle development, water transport, DNA repair, reproduction, nervous system development, and immunity. Collectively, our results demonstrated that indels and SVs could capture additional signatures besides SNPs. Furthermore, similar but distinct gene functions among different types of genomic variants collectively and complementarily drive genomic divergence across environmental gradients in such a high-elevation endemic species, underscoring its evolutionary relevance in local adaptation.

indels

Safe and Stable Germline Transmission of MSTN Mutations in Cattle.

With the global population expected to reach 10 billion by 2050, sustainable livestock production is critical. Gene editing of the myostatin (MSTN) gene represents a promising strategy to enhance muscle growth in cattle. In this study, MSTN-mutated founder (F0) cows were used to generate F1 offspring via ovum pick-up, in&#xa0;vitro fertilization, and embryo transfer. Four F1 calves were born, all confirmed to be heterozygous for the MSTN mutation. Long-term monitoring showed normal growth and no visible health abnormalities. Whole-genome sequencing identified SNPs, INDELs, and structural variants, most with minimal predicted functional effects. Proteomic profiling of Longissimus dorsi muscle quantified 2947 proteins, revealing only subtle expression differences between MSTN-mutated and wild-type cattle. These results demonstrate stable inheritance and confirm that MSTN editing does not disrupt genome integrity or protein expression. Overall, our findings support the safety and utility of MSTN gene editing to improve livestock productivity for future food security.

Animals

Mutagenic Impact and Evolutionary Influence of Chemoradiotherapy in Hematologic Malignancies.

UNLABELLED: Ionizing radiotherapy (RT) is a widely used treatment strategy for malignancies. In solid tumors, RT-induced double-strand breaks lead to the accumulation of insertion-deletions (indels; ID), and their repair by nonhomologous end joining has been linked to the ID8 mutational signature in surviving cells. However, the extent of RT-induced mutagenesis in hematologic malignancies and its impact on their mutational profiles and interplay with commonly used chemotherapies has not yet been explored. In this study, we interrogated 580 whole-genome sequence (WGS) samples from patients with large B-cell lymphoma, multiple myeloma, and myeloid neoplasms and identified ID8 only in relapsed disease. Yet ID8 was detected after exposure to both RT and mutagenic chemotherapy (i.e., platinum and melphalan). Using WGS of single-cell colonies derived from treated lymphoma cells, we revealed a dose-response relationship between RT and platinum and ID8. Finally, using ID8 as a genomic barcode, we demonstrate that a single RT-surviving cell may seed distant relapse. SIGNIFICANCE: RT and the ID8 indel signature are related, but their genomic impact on hematologic malignancies is unclear. Leveraging WGS, we linked ID8 to both RT and mutagenic chemotherapy and validated that platinum can induce ID8. We used ID8 as a genomic barcode to reveal that RT-resistant cells may seed systemic relapse.

Humans

Whole genome and exome sequencing of pancreatic neuroendocrine tumour to investigate PRRT response.

Patients with pancreatic neuroendocrine tumours (PNETs) often have similar baseline clinical characteristics, including grade and molecular imaging phenotype, yet have highly variable responses to peptide receptor radionuclide therapy (PRRT). To identify genomic alterations and mutational patterns associated with PRRT treatment response and acquired somatic changes following PRRT exposure, whole genome or exome sequencing was applied to 40 PNET samples from 32 patients, including eight paired pre- or post-PRRT samples. The genomic profile of tumours reflected the known mutational landscape of PNET with MEN1 (34%), ATRX/DAXX (47%) alterations and a recurrent pattern of aneuploidy (38%) detected. A recurrent PSIP1::TBL1X fusion of unknown function was also identified in four tumours. The disease control rate following PRRT using RECIST1.1 and molecular imaging criteria was 88% (28/32). No mutational features were found to be statistically associated with progression-free survival. There was no significant increase in tumour mutational burden in the post-PRRT tumours, nor recurrent emergent mutational changes in cancer driver genes to explain progression to higher-grade disease, when observed. However, a small indel signature (ID8) previously associated with DNA damage repair by non-homologous end joining (NHEJ) was higher in PRRT-exposed compared with PRRT-naive samples (23.8 vs 4.8%, respectively; P < 0.001). Thus, comprehensive DNA analysis of pancreatic NETs did not identify biomarkers predictive of PRRT response nor evidence for high-level PRRT-induced genomic instability or hypermutation, yet mutation signature analysis supports NHEJ as being important for DNA repair and survival of neuroendocrine cells following exposure to beta-particle radiation.

Humans

fRagmentomics: an R package for integrating cell-free DNA fragment features with mutational status to support liquid biopsy interpretation.

SUMMARY: Liquid biopsy offers a non-invasive approach to study tumor-derived genetic material circulating in plasma. Beyond genetic alterations, the fragmentomic features of cell-free DNA-such as fragment size, genomic position, and end-motifs-provide valuable insights into the biological and clinical context of DNA release. fRagmentomics is a user-friendly R package designed to characterize cfDNA fragments overlapping one or multiple small mutations of any type, starting from an aligned sequencing file (BAM). It supports multiple mutation input formats, accommodates one-based and zero-based genomic conventions, resolves mutation representation ambiguities, and accepts any reference file in FASTA format. For each fragment overlapping a mutation of interest, fRagmentomics outputs fragment-level features including its fragment size, end-motifs, and mutational status, along with additional fragment-level or read-level information. The package implements an indel-aware and optionally soft-clip-preserving fragment size computation that improves accuracy over conventional size estimates based solely on aligned positions. AVAILABILITY AND IMPLEMENTATION: fRagmentomics is licensed under GNU General Public License v3.0 and available at https://github.com/ElsaB-Lab/fRagmentomics, https://anaconda.org/elsab-lab/r-fragmentomics and https://bioconductor.org/packages/fRagmentomics, with documentation and a tutorial. CONTACT: yoann.pradat@gustaveroussy.fr, elsa.bernard@gustaveroussy.fr. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Software

Genome-scale multi-organ analysis of mutagenic effects of ethanol and acetaldehyde in Sprague Dawley rats.

Alcohol consumption is a major cancer risk factor, particularly for head and neck cancers, including the oral cavity. Acetaldehyde, the primary genotoxic metabolite of ethanol, may play key roles in oral carcinogenesis, though the mechanisms remain unclear. While mutational signatures SBS16, DBS4, and ID11 have been tentatively linked to alcohol use, they are not exclusive to alcohol-related cancers. In this study, we examined the genome-wide in vivo mutagenic effects of ethanol and acetaldehyde by analyzing tumors from the cheek, Zymbal gland, larynx, forestomach, and liver of rats chronically exposed to these compounds. Signature analysis revealed exposure-specific, early-onset formation of SBS17 in ~28% of head and neck tumors, suggesting inflammation and/or oxidative damage as potential mediators of carcinogenesis. Cancer driver gene analysis identified a relative enrichment of exposed tumors with mutations in the Tp53 and Mtor genes. No notable exposure-specific changes were observed in doublet-base substitutions, indel signatures, or copy number variants. Notably, SBS16, DBS4, and ID11 were absent. Our findings suggest direct mutagenicity may not be the main driver of alcohol-related cancer. Other harmful cellular effects, undetectable by whole genome sequencing, may be involved. Our findings suggest that SBS17 could function as a potential exposure-specific molecular marker of alcohol-related cancers in humans.

Journal Article