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The three-dimensional (3D) structure of chromatin is intrinsically associated with gene regulation and cell function1–3. Methods based on chromatin conformation capture have mapped chromatin structures in neuronal systems such as in vitro differentiated neurons, neurons isolated through fluorescence-activated cell sorting from cortical tissues pooled from different animals and from dissociated whole hippocampi4–6. However, changes in chromatin organization captured by imaging, such as the relocation of Bdnf away from the nuclear periphery after activation7, are invisible with such approaches8. Here we developed immunoGAM, an extension of genome architecture mapping (GAM)2,9, to map 3D chromatin topology genome-wide in specific brain cell types, without tissue disruption, from single animals. GAM is a ligation-free technology that maps genome topology by sequencing the DNA content from thin (about 220 nm) nuclear cryosections. Chromatin interactions are identified from the increased probability of co-segregation of contacting loci across a collection of nuclear slices. ImmunoGAM expands the scope of GAM to enable the selection of specific cell types using low cell numbers (approximately 1,000 cells) within a complex tissue and avoids tissue dissociation2,10. We report cell-type specialized 3D chromatin structures at multiple genomic scales that relate to patterns of gene expression. We discover extensive ‘melting’ of long genes when they are highly expressed and/or have high chromatin accessibility. The contacts most specific of neuron subtypes contain genes associated with specialized processes, such as addiction and synaptic plasticity, which harbour putative binding sites for neuronal transcription factors within accessible chromatin regions. Moreover, sensory receptor genes are preferentially found in heterochromatic compartments in brain cells, which establish strong contacts across tens of megabases. Our results demonstrate that highly specific chromatin conformations in brain cells are tightly related to gene regulation mechanisms and specialized functions., A new technique called immunoGAM, which combines genome architecture mapping (GAM) with immunoselection, enabled the discovery of specialized chromatin conformations linked to gene expression in specific cell populations from mouse brain tissues.

BACKGROUNDGenetic testing for breast cancer susceptibility is widely used, but for many genes,evidence of an association with breast cancer is weak, underlying risk estimatesare imprecise, and reliable subtype-specific risk estimates are lacking.METHODSWe used a panel of 34 putative susceptibility genes to perform sequencing onsamples from 60,466 women with breast cancer and 53,461 controls. In separateanalyses for protein-truncating variants and rare missense variants in these genes,we estimated odds ratios for breast cancer overall and tumor subtypes. We evaluatedmissense-variant associations according to domain and classification of pathogenicity.RESULTSProtein-truncating variants in 5 genes (ATM, BRCA1, BRCA2, CHEK2, and PALB2)were associated with a risk of breast cancer overall with a P value of less than0.0001. Protein-truncating variants in 4 other genes (BARD1, RAD51C, RAD51D,and TP53) were associated with a risk of breast cancer overall with a P value ofless than 0.05 and a Bayesian false-discovery probability of less than 0.05. Forprotein-truncating variants in 19 of the remaining 25 genes, the upper limit ofthe 95% confidence interval of the odds ratio for breast cancer overall was lessthan 2.0. For protein-truncating variants in ATM and CHEK2, odds ratios werehigher for estrogen receptor (ER)–positive disease than for ER-negative disease;for protein-truncating variants in BARD1, BRCA1, BRCA2, PALB2, RAD51C, andRAD51D, odds ratios were higher for ER-negative disease than for ER-positivedisease. Rare missense variants (in aggregate) in ATM, CHEK2, and TP53 wereassociated with a risk of breast cancer overall with a P value of less than 0.001.For BRCA1, BRCA2, and TP53, missense variants (in aggregate) that would be classified as pathogenic according to standard criteria were associated with a riskof breast cancer overall, with the risk being similar to that of protein-truncatingvariants.CONCLUSIONSThe results of this study define the genes that are most clinically useful for inclusion on panels for the prediction of breast cancer risk, as well as provide estimatesof the risks associated with protein-truncating variants, to guide genetic counseling. (Funded by European Union Horizon 2020 programs and others.)

This presentation describes ongoing work in the modelling of usage information in the context of the MORDigital project.

Background Protein truncating variants in ATM, BRCA1, BRCA2, CHEK2, and PALB2 are associated with increased breast cancer risk, but risks associated with missense variants in these genes are uncertain. Methods We analyzed data on 59,639 breast cancer cases and 53,165 controls from studies participating in the Breast Cancer Association Consortium BRIDGES project. We sampled training (80%) and validation (20%) sets to analyze rare missense variants in ATM (1146 training variants), BRCA1 (644), BRCA2 (1425), CHEK2 (325), and PALB2 (472). We evaluated breast cancer risks according to five in silico prediction-of-deleteriousness algorithms, functional protein domain, and frequency, using logistic regression models and also mixture models in which a subset of variants was assumed to be risk-associated. Results The most predictive in silico algorithms were Helix (BRCA1, BRCA2 and CHEK2) and CADD (ATM). Increased risks appeared restricted to functional protein domains for ATM (FAT and PIK domains) and BRCA1 (RING and BRCT domains). For ATM, BRCA1, and BRCA2, data were compatible with small subsets (approximately 7%, 2%, and 0.6%, respectively) of rare missense variants giving similar risk to those of protein truncating variants in the same gene. For CHEK2, data were more consistent with a large fraction (approximately 60%) of rare missense variants giving a lower risk (OR 1.75, 95% CI (1.47–2.08)) than CHEK2 protein truncating variants. There was little evidence for an association with risk for missense variants in PALB2. The best fitting models were well calibrated in the validation set. Conclusions These results will inform risk prediction models and the selection of candidate variants for functional assays and could contribute to the clinical reporting of gene panel testing for breast cancer susceptibility.

© 2022, Chora, Pedroso et al. This article is distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use and redistribution provided that the original author and source are credited., Anthracyclines are among the most used and effective anticancer drugs. Their activity has been attributed to DNA double-strand breaks resulting from topoisomerase II poisoning and to eviction of histones from select sites in the genome. Here, we show that the extensively used anthracyclines Doxorubicin, Daunorubicin, and Epirubicin decrease the transcription of nuclear factor kappa B (NF-κB)-dependent gene targets, but not interferon-responsive genes in primary mouse (Mus musculus) macrophages. Using an NMR-based structural approach, we demonstrate that anthracyclines disturb the complexes formed between the NF-κB subunit RelA and its DNA-binding sites. The anthracycline variants Aclarubicin, Doxorubicinone, and the newly developed Dimethyl-doxorubicin, which share anticancer properties with the other anthracyclines but do not induce DNA damage, also suppressed inflammation, thus uncoupling DNA damage from the effects on inflammation. These findings have implications for anticancer therapy and for the development of novel anti-inflammatory drugs with limited side effects for life-threatening conditions such as sepsis., This work was supported by the European Commission Horizon 2020 (ERC-2014-CoG 647888-iPROTECTION) and by Fundação para a Ciência e Tecnologia (FCT: PTDC/BIM-MEC/4665/2014 and EXPL/MED-IMU/0620/2021). SW is funded by the Deutsche Forschungsgemeinschaft, DFG, project number WE 4971/6-1, the Excellence Cluster Balance of the Microverse (EXC 2051; 390713860), and the Federal Ministry of Education and Research (BMBF) project number 01EN2001.

Malnutrition in the elderly is not only common but often overlooked which can result in multiple medical complications, hospital admissions and even death. Objective: The objective of this study was to evaluate the nutritional risk in institutionalized elderly in a Private Institution of Social Solidarity in the municipality of Vila Real. Material and Methods: The sample consists of 55 elderly people, aged between 65 and 101 years (84.69 +/- 8.303 years). Twenty are male and thirty-five are female. The prevalence of malnutrition and risk of malnutrition was obtained through anthropometric measurements, weight and height to calculate the Body Mass Index (BMI), arm circumference, geminal circumference and waist circumference and applying the Mini Nutritional Assessment (MNA) scale. Results: Men had greater weight and height than women (p

PALB2 loss-of-function variants confer high risk of developing breast cancer. Here, we present a systematic functional analysis of PALB2 splice-site variants detected in ~113,000 women of the large-scale sequencing project BRIDGES (Breast Cancer After Diagnostic Gene Sequencing; https://bridges-research.eu/). Eighty-two PALB2 variants at the intron-exon boundaries were analyzed with MaxEntScan. Forty-two variants were selected for the subsequent splicing functional assays. For this purpose, three splicing reporter minigenes comprising exons 1-12 were constructed. The 42 potential spliceogenic variants were introduced into the minigenes by site-directed mutagenesis and assayed in MCF-7/MDA-MB-231 cells. Splicing anomalies were observed in 35 variants, 23 of which showed no traces or minimal amounts of the expected full-length transcripts of each minigene. More than 30 different variant-induced transcripts were characterized, 23 of which were predicted to truncate the PALB2 protein. The pathogenicity of all variants was interpreted according to an in-house adaptation of the ACMG/AMP (American College of Medical Genetics and Genomics and the Association for Molecular Pathology) variant classification scheme. Up to 23 variants were classified as Pathogenic/Likely Pathogenic. Remarkably, three ±1,2 variants (c.49-2A>T, c.108+2T>C and c.211+1G>A) were classified as variants of unknown significance since they produced significant amounts of either in-frame transcripts of unknown impact on the PALB2 protein function or the minigene full-length transcripts. In conclusion, we have significantly contributed to the ongoing effort of identifying spliceogenic variants in the clinically relevant PALB2 cancer susceptibility gene. Moreover, we suggest some approaches to classify the findings in accordance with the ACMG/AMP rationale., PD, MPGV, DFE, MdlH, and EAV have received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement no. 634935. The laboratory of EAV is supported by grants from the Spanish Ministry of Science and Innovation, Plan Nacional de I+D+I 2013-2016, ISCIII (PI17/00227 and PI20/00225) co-funded by FEDER from Regional Development European Funds (European Union) and from the Consejería de Educacion, Junta de Castilla y Leon, ref. CSI242P18 (actuacion cofinanciada P.O. FEDER 2014-2020 de Castilla y Leon). The laboratory of MdlH is supported by a grant from the Spanish Ministry of Science and Innovation, Plan Nacional de I+D+I 2013-2016, ISCIII (PI20/00110) co-funded by FEDER from Regional Development European Funds (European Union). Programa Estratégico Instituto de Biología y Genética Molecular (IBGM), Escalera de Excelencia, Junta de Castilla y León (ref. CLU-2019-02). AV-P is supported by a predoctoral fellowship from the Consejería de Educación, Junta de Castilla y León (2018–2022). LS-M is supported by a predoctoral fellowship from the AECC-Scientific Foundation, Sede Provincial de Valladolid (2019–2023). AE-S is supported through the Operational Program for Youth Employment and Youth Employment Initiative (YEI), called by the Community of Madrid in 2020, and co-financed by the European Social Fund.