Recent evidence suggests that genome-wide allelic imbalances are inducible by carcinogens and may occur as cells adapt to carcinogenic exposure during tumorigenesis. We investigated the role of carcinogenic exposure on global and selected loss of heterozygosity (LOH) during mouse lung adenocarcinogenesis. Tumor induction by 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) or vinyl carbamate (VC) resulted in a significant overall increase in the number of chromosomes affected by LOH per tumor when compared with spontaneous lung tumors. Allelic loss on chromosome 12 occurred at a frequency of 35% and 40% in NNK- and VC-induced tumors, respectively, compared with 8.3% in spontaneous tumors (P < 0.01). In contrast, spontaneous lung adenocarcinomas displayed LOH on chromosome 4 at a frequency of 77%, whereas a frequency of only 36% (P < 0.001) was observed in tumors induced by NNK. Sixty-four percent of the VC-induced tumors displayed LOH on chromosome 4. In addition, allelic losses on chromosomes 12 and 14 were significantly associated with an increase in chromosomal instability, suggesting that genes inactivated on these chromosomes may contribute to this effect. The results from this study demonstrate that genotoxic carcinogens increase chromosome instability, as evidenced by a significant increase in global LOH frequency, and significantly alter the selection of chromosomal alterations during lung tumor development.
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Mol Biol Rep
January 2025
Zoological Survey of India, Kolkata, 700053, India.
Background: The endangered Kashmir musk deer (Moschus cupreus), native to high-altitude Himalayas, is an ecological significant and endangered ungulate, threatened by habitat loss and poaching for musk pod distributed in western Himalayan ranges of India, Nepal and Afghanistan. Despite its critical conservation status and ecological importance in regulating vegetation dynamics, knowledge gaps persist regarding its population structure and genetic diversity, hindering effective management strategies.
Methods And Results: We aimed to understand the population genetics of Kashmir musk deer in north-western Himalayas using two mitochondrial DNA (mtDNA) regions and 11 microsatellite loci.
Hybridisation is a source of genetic diversity, can drive adaptation to new niches and has been found to be a frequent event in lineages harbouring pathogenic fungi. However, little is known about the genomic implications of hybridisation nor its impact on pathogenicity-related traits. A common limitation for addressing these questions is the narrow representativity of sequenced genomes, mostly corresponding to strains isolated from infected patients.
View Article and Find Full Text PDFRemnant populations of endangered species often have complex demographic histories associated with human impact. This can present challenges for conservation as populations modified by human activity may require bespoke management. The Eurasian red squirrel, (L.
View Article and Find Full Text PDFCell
January 2025
European Molecular Biology Laboratory, European Bioinformatics Institute, Hinxton CB10 1SA, UK. Electronic address:
Osteosarcoma is the most common primary cancer of the bone, with a peak incidence in children and young adults. Using multi-region whole-genome sequencing, we find that chromothripsis is an ongoing mutational process, occurring subclonally in 74% of osteosarcomas. Chromothripsis generates highly unstable derivative chromosomes, the ongoing evolution of which drives the acquisition of oncogenic mutations, clonal diversification, and intra-tumor heterogeneity across diverse sarcomas and carcinomas.
View Article and Find Full Text PDFNeurol Genet
February 2025
Memory Center, Keio University School of Medicine, Tokyo, Japan.
Background And Objectives: A previous postmortem study of men with Christianson syndrome, a disorder caused by loss-of-function mutations in the gene , reported a mechanistic link between pathologic tau accumulation and progressive symptoms such as cerebellar atrophy and cognitive decline. This study aimed to characterize the relationships between neuropathologic manifestations and tau accumulation in heterozygous women with mutation.
Methods: We conducted a multimodal neuroimaging and plasma biomarker study on 3 middle-aged heterozygous women with mutations (proband 1: mid-50s; proband 2: early 50s; proband 3: mid-40s) presenting with progressive extrapyramidal symptoms.
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