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Spinal muscular atrophy, a leading cause of early infant death, is caused by bi-allelic mutations of SMN1. Sequence analysis of SMN1 is challenging due to high sequence similarity with its paralog SMN2. Both genes have variable copy numbers across populations. Furthermore, without pedigree information, it is currently not possible to identify silent carriers (2+0) with two copies of SMN1 on one chromosome and zero copies on the other. We developed Paraphase, an informatics method that identifies full-length SMN1 and SMN2 haplotypes, determines the gene copy numbers, and calls phased variants using long-read PacBio HiFi data. The SMN1 and SMN2 copy-number calls by Paraphase are highly concordant with orthogonal methods (99.2% for SMN1 and 100% for SMN2). We applied Paraphase to 438 samples across 5 ethnic populations to conduct a population-wide haplotype analysis of these highly homologous genes. We identified major SMN1 and SMN2 haplogroups and characterized their co-segregation through pedigree-based analyses. We identified two SMN1 haplotypes that form a common two-copy SMN1 allele in African populations. Testing positive for these two haplotypes in an individual with two copies of SMN1 gives a silent carrier risk of 88.5%, which is significantly higher than the currently used marker (1.7%-3.0%). Extending beyond simple copy-number testing, Paraphase can detect pathogenic variants and enable potential haplotype-based screening of silent carriers through statistical phasing of haplotypes into alleles. Future analysis of larger population data will allow identification of more diverse haplotypes and genetic markers for silent carriers.
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Atrofia Muscular Espinal , Lactante , Humanos , Atrofia Muscular Espinal/genética , Atrofia Muscular Espinal/diagnóstico , Mutación , Dosificación de Gen , Linaje , Análisis de Secuencia , Proteína 1 para la Supervivencia de la Neurona Motora/genética , Proteína 2 para la Supervivencia de la Neurona Motora/genéticaRESUMEN
Copy-number changes generate phenotypic variability in health and disease. Whether organisms protect against copy-number changes is largely unknown. Here, we show that Saccharomyces cerevisiae monitors the copy number of its ribosomal DNA (rDNA) and rapidly responds to copy-number loss with the clonal amplification of extrachromosomal rDNA circles (ERCs) from chromosomal repeats. ERC formation is replicative, separable from repeat loss, and reaches a dynamic steady state that responds to the addition of exogenous rDNA copies. ERC levels are also modulated by RNAPI activity and diet, suggesting that rDNA copy number is calibrated against the cellular demand for rRNA. Last, we show that ERCs reinsert into the genome in a dosage-dependent manner, indicating that they provide a reservoir for ultimately increasing rDNA array length. Our results reveal a DNA-based mechanism for rapidly restoring copy number in response to catastrophic gene loss that shares fundamental features with unscheduled copy-number amplifications in cancer cells.
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Variaciones en el Número de Copia de ADN/fisiología , ADN Circular/fisiología , ADN Ribosómico/fisiología , Variaciones en el Número de Copia de ADN/genética , Replicación del ADN/fisiología , ADN Circular/genética , ADN Circular/metabolismo , ADN Ribosómico/genética , Proteínas de Unión al ADN/fisiología , Genómica , ARN Ribosómico/genética , Recombinación Genética/genética , Ribosomas/fisiología , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genéticaRESUMEN
Gestational diabetes mellitus (GDM) is a common complication of pregnancy, which has significant adverse effects on both the mother and fetus. The incidence of GDM is increasing globally, and early diagnosis is critical for timely treatment and reducing the risk of poor pregnancy outcomes. GDM is usually diagnosed and detected after 24 weeks of gestation, while complications due to GDM can occur much earlier. Copy number variations (CNVs) can be a possible biomarker for GDM diagnosis and screening in the early gestation stage. In this study, we proposed a machine-learning method to screen GDM in the early stage of gestation using cell-free DNA (cfDNA) sequencing data from maternal plasma. Five thousand and eighty-five patients from north regions of Mainland China, including 1942 GDM, were recruited. A non-overlapping sliding window method was applied for CNV coverage screening on low-coverage (~0.2×) sequencing data. The CNV coverage was fed to a convolutional neural network with attention architecture for the binary classification. The model achieved a classification accuracy of 88.14%, precision of 84.07%, recall of 93.04%, F1-score of 88.33% and AUC of 96.49%. The model identified 2190 genes associated with GDM, including DEFA1, DEFA3 and DEFB1. The enriched gene ontology (GO) terms and KEGG pathways showed that many identified genes are associated with diabetes-related pathways. Our study demonstrates the feasibility of using cfDNA sequencing data and machine-learning methods for early diagnosis of GDM, which may aid in early intervention and prevention of adverse pregnancy outcomes.
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Ácidos Nucleicos Libres de Células , Aprendizaje Profundo , Diabetes Gestacional , beta-Defensinas , Femenino , Embarazo , Humanos , Diabetes Gestacional/diagnóstico , Diabetes Gestacional/genética , Variaciones en el Número de Copia de ADN , Resultado del Embarazo , Ácidos Nucleicos Libres de Células/genéticaRESUMEN
Replication stress (RS) is a key trait of cancer cells, and a potential actionable target in cancer treatment. Accurate methods to measure RS in tumour samples are currently lacking. DNA fibre analysis has been used as a common technique to measure RS in cell lines. Here, we investigated DNA fibre analysis on fresh breast cancer specimens and correlated DNA replication kinetics to known RS markers and genomic alterations. Fresh, treatment-naïve primary breast cancer samples (n = 74) were subjected to ex vivo DNA fibre analysis to measure DNA replication kinetics. Tumour cell proliferation was confirmed by EdU incorporation and cytokeratin AE1/AE3 (CK) staining. The RS markers phospho-S33-RPA and γH2AX and the RS-inducing proto-oncogenes Cyclin E1 and c-Myc were analysed by immunohistochemistry. Copy number variations (CNVs) were assessed from genome-wide single nucleotide polymorphism (SNP) arrays. We found that the majority of proliferating (EdU-positive) cells in each sample were CK-positive and therefore considered to be tumour cells. DNA fibre lengths varied largely in most tumour samples. The median DNA fibre length showed a significant inverse correlation with pRPA expression (r = -0.29, p = 0.033) but was not correlated with Cyclin E1 or c-Myc expression and global CNVs in this study. Nuclear Cyclin E1 expression showed a positive correlation with pRPA levels (r = 0.481, p < 0.0001), while cytoplasmic Cyclin E1 expression exhibited an inverse association with pRPA expression (r = -0.353, p = 0.002) and a positive association with global CNVs (r = 0.318, p = 0.016). In conclusion, DNA fibre analysis performed with fresh primary breast cancer samples is feasible. Fibre lengths were associated with pRPA expression. Cyclin E1 expression was associated with pRPA and the percentage of CNVs. © 2024 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
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Neoplasias de la Mama , Ciclina E , Replicación del ADN , Humanos , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Neoplasias de la Mama/metabolismo , Femenino , Ciclina E/genética , Ciclina E/metabolismo , Replicación del ADN/genética , Polimorfismo de Nucleótido Simple , Proliferación Celular , Variaciones en el Número de Copia de ADN , Persona de Mediana Edad , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Proteínas Oncogénicas/genética , Proteínas Oncogénicas/metabolismo , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Anciano , ADN de Neoplasias/genética , ADN de Neoplasias/metabolismo , AdultoRESUMEN
Mesonephric-like adenocarcinoma (MLA) of the female genital tract is an uncommon histotype that can arise in both the endometrium and the ovary. The exact cell of origin and histogenesis currently remain unknown. Here, we investigated whole genome DNA methylation patterns and copy number variations (CNVs) in a series of MLAs in the context of a large cohort of various gynaecological carcinoma types. CNV analysis of 19 MLAs uncovered gains of chromosomes 1q (18/19, 95%), 10 (15/19, 79%), 12 (14/19, 74%), and 2 (10/19, 53%), as well as loss of chromosome 1p (7/19, 37%). Gains of chromosomes 1q, 10, and 12 were also identified in the majority of mesonephric adenocarcinomas of the uterine cervix (MAs) as well as subsets of endometrioid carcinomas (ECs) and low-grade serous carcinomas of the ovary (LGSCs) but only in a minority of serous carcinomas of the uterine corpus (USCs), clear cell carcinomas (CCCs), and tubo-ovarian high-grade serous carcinomas (HGSCs). While losses of chromosome 1p together with gains of chromosome 1q were also identified in both MA and LGSC, gains of chromosome 2 were almost exclusively identified in MLA and MA. Unsupervised hierarchical clustering and t-SNE analysis of DNA methylation data (Illumina EPIC array) identified a co-clustering for MLAs and MAs, which was distinct from clusters of ECs, USCs, CCCs, LGSCs, and HGSCs. Group-wise comparisons confirmed a close epigenetic relationship between MLA and MA. These findings, in conjunction with the established histological and immunophenotypical overlap, suggest bona fide mesonephric differentiation, and support a more precise terminology of mesonephric-type adenocarcinoma instead of MLA in these tumours. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
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Carcinoma Endometrioide , Cistadenocarcinoma Seroso , Neoplasias Ováricas , Femenino , Humanos , Cuello del Útero/patología , Variaciones en el Número de Copia de ADN , Metilación de ADN , Carcinoma Endometrioide/genética , Carcinoma Endometrioide/patología , Cistadenocarcinoma Seroso/genética , Carcinoma Epitelial de Ovario/genética , Neoplasias Ováricas/genética , Neoplasias Ováricas/patologíaRESUMEN
Technologies for detecting structural variation (SV) have advanced with the advent of long-read sequencing, which enables the validation of SV at a nucleotide level. Optical genome mapping (OGM), a technology based on physical mapping, can also provide comprehensive SVs analysis. We applied long-read whole genome sequencing (LRWGS) to accurately reconstruct breakpoint (BP) segments in a patient with complex chromosome 6q rearrangements that remained elusive by conventional karyotyping. Although all BPs were precisely identified by LRWGS, there were two possible ways to construct the BP segments in terms of their orders and orientations. Thus, we also used OGM analysis. Notably, OGM recognized entire inversions exceeding 500 kb in size, which LRWGS could not characterize. Consequently, here we successfully unveil the full genomic structure of this complex chromosomal 6q rearrangement and cryptic SVs through combined long-molecule genomic analyses, showcasing how LRWGS and OGM can complement each other in SV analysis.
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Cryptorchidism is the most common urologic birth defect in men and is a predisposing factor of male infertility and testicular cancer, yet the etiology remains largely unknown. E2F1 microdeletions and microduplications contribute to cryptorchidism, infertility and testicular tumors. Although E2f1 deletion or overexpression in mice causes spermatogenic failure, the mechanism by which E2f1 influences testicular function is unknown. This investigation revealed that E2f1-null mice develop cryptorchidism with severe gubernacular defects and progressive loss of germ cells resulting in infertility and, in rare cases, testicular tumors. It was hypothesized that germ cell depletion resulted from an increase in WNT4 levels. To test this hypothesis, the phenotype of a double-null mouse model lacking both Wnt4 and E2f1 in germ cells was analyzed. Double-null mice are fertile. This finding indicates that germ cell maintenance is dependent on E2f1 repression of Wnt4, supporting a role for Wnt4 in germ cell survival. In the future, modulation of WNT4 expression in men with cryptorchidism and spermatogenic failure due to E2F1 copy number variations may provide a novel approach to improve their spermatogenesis and perhaps their fertility potential after orchidopexy.
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Factor de Transcripción E2F1/metabolismo , Espermatogénesis , Testículo/metabolismo , Proteína Wnt4/metabolismo , Envejecimiento/patología , Animales , Animales Recién Nacidos , Barrera Hematotesticular/patología , Ciclo Celular/genética , Criptorquidismo/genética , Criptorquidismo/patología , Factor de Transcripción E2F1/deficiencia , Fertilidad , Regulación de la Expresión Génica , Masculino , Ratones Endogámicos C57BL , Modelos Biológicos , Transducción de Señal , Espermatozoides/metabolismo , Testículo/patologíaRESUMEN
BACKGROUND: Genetic disorders often manifest as abnormal fetal or childhood development. Copy number variations (CNVs) represent a significant genetic mechanism underlying such disorders. Despite their importance, the effectiveness of clinical exome sequencing (CES) in detecting CNVs, particularly small ones, remains incompletely understood. We aimed to evaluate the detection of both large and small CNVs using CES in a substantial clinical cohort, including parent-offspring trios and proband only analysis. METHODS: We conducted a retrospective analysis of CES data from 2428 families, collected from 2018 to 2021. Detected CNV were categorized as large or small, and various validation techniques including chromosome microarray (CMA), Multiplex ligation-dependent probe amplification assay (MLPA), and/or PCR-based methods, were employed for cross-validation. RESULTS: Our CNV discovery pipeline identified 171 CNV events in 154 cases, resulting in an overall detection rate of 6.3%. Validation was performed on 113 CNVs from 103 cases to assess CES reliability. The overall concordance rate between CES and other validation methods was 88.49% (100/113). Specifically, CES demonstrated complete consistency in detecting large CNV. However, for small CNVs, consistency rates were 81.08% (30/37) for deletions and 73.91% (17/23) for duplications. CONCLUSION: CES demonstrated high sensitivity and reliability in CNV detection. It emerges as an economical and dependable option for the clinical CNV detection in cases of developmental abnormalities, especially fetal structural abnormalities.
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Variaciones en el Número de Copia de ADN , Secuenciación del Exoma , Enfermedades Genéticas Congénitas , Humanos , Variaciones en el Número de Copia de ADN/genética , Enfermedades Genéticas Congénitas/diagnóstico , Enfermedades Genéticas Congénitas/genética , Reproducibilidad de los Resultados , Femenino , Valor Predictivo de las Pruebas , Masculino , Estudios RetrospectivosRESUMEN
BACKGROUND: Diagnosis and monitoring of leptomeningeal malignancy remain challenging, and are usually based on neurological, radiological, cerebrospinal fluid (CSF) and pathological findings. This study aimed to investigate the diagnostic performance of CSF metagenomic next-generation sequencing (mNGS) and chromosome copy number variations (CNVs) analysis in the detection of leptomeningeal malignancy. METHODS: Of the 51 patients included in the study, 34 patients were diagnosed with leptomeningeal malignancies, and 17 patients were diagnosed with central nervous system (CNS) inflammatory diseases. The Sayk's spontaneous cell sedimentation technique was employed for CSF cytology. And a well-designed approach utilizing the CSF mNGS-CNVs technique was explored for early diagnosis of leptomeningeal malignancy. RESULTS: In the tumor group, 28 patients were positive for CSF cytology, and 24 patients were positive for CSF mNGS-CNVs. Sensitivity and specificity of CSF cytology were 82.35% (95% CI: 66.83-92.61%) and 94.12% (95% CI: 69.24-99.69%). In comparison, sensitivity and specificity of CSF mNGS-CNV were 70.59% (95% CI: 52.33-84.29%) and 100% (95% CI: 77.08-100%). There was no significant difference in diagnostic consistency between CSF cytology and mNGS-CNVs (p = 0.18, kappa = 0.650). CONCLUSIONS: CSF mNGS-CNVs tend to have higher specificity compared with traditional cytology and can be used as a complementary diagnostic method for patients with leptomeningeal malignancies.
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Variaciones en el Número de Copia de ADN , Secuenciación de Nucleótidos de Alto Rendimiento , Neoplasias Meníngeas , Metagenómica , Humanos , Masculino , Femenino , Neoplasias Meníngeas/líquido cefalorraquídeo , Neoplasias Meníngeas/genética , Neoplasias Meníngeas/diagnóstico , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Persona de Mediana Edad , Variaciones en el Número de Copia de ADN/genética , Adulto , Metagenómica/métodos , Anciano , Adulto Joven , Sensibilidad y Especificidad , Adolescente , CitologíaRESUMEN
Schizophrenia is a neuropsychiatric disorder characterized by various symptoms such as hallucinations, delusions, and disordered thinking. The etiology of this disease is unknown; however, it has been linked to many microdeletion syndromes that are likely to contribute to the pathology of schizophrenia. In this review we have comprehensively analyzed the role of various microdeletion syndromes, like 3q29, 15q13.3, and 22q11.2, which are known to be involved with schizophrenia. A variety of factors lead to schizophrenia phenotypes, but copy number variants that disrupt gene regulation and impair brain function and cognition are one of the causes that have been identified. Multiple case studies have shown that loss of one or more genes in the microdeletion regions lead to brain activity defects. In this article, we present a coherent paradigm that connects copy number variations (CNVs) to numerous neurological and behavioral abnormalities associated with schizophrenia. It would be helpful in understanding the different aspects of the microdeletions and how they contribute in the pathophysiology of schizophrenia.
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Deleción Cromosómica , Variaciones en el Número de Copia de ADN , Esquizofrenia , Humanos , Esquizofrenia/genética , Variaciones en el Número de Copia de ADN/genética , Fenotipo , Cromosomas Humanos Par 15/genética , Predisposición Genética a la Enfermedad , Discapacidad Intelectual/genética , Trastornos de los Cromosomas/genética , Discapacidades del Desarrollo , Cromosomas Humanos Par 3 , ConvulsionesRESUMEN
OBJECTIVE: To examine the prenatal profiles of pregnancies affected by an atypical chromosomal aberration, focusing on pathogenic copy number variants (pCNVs). Further, we wanted to quantify the performance of combined first-trimester screening (cFTS) and a second-trimester anomaly scan in detecting these conditions. Finally, we aimed to estimate the consequences of a policy of using non-invasive prenatal testing (NIPT) rather than invasive testing with chromosomal microarray (CMA) to manage pregnancies identified as high risk from cFTS. METHODS: A retrospective review of the Danish fetal medicine database identified all pregnant women who had cFTS and a trisomy 21 risk-assessment between January 1, 2008, and December 31, 2018. Chromosomal aberrations diagnosed prenatally, postnatally, or from fetal tissue following pregnancy loss or termination of pregnancy (TOP) were identified. Chromosomal aberrations were grouped into one of six categories: 1) Triploidy; 2) Common trisomies (trisomies 21, 18, and 13); 3) Monosomy X; 4) Other sex chromosome aberrations (SCAs); 5) pCNVs; and 6) Rare autosomal trisomies (RATs) and mosaicisms. The prevalence of each aberration-category was stratified by the individual cFTS markers and risk estimate, and the size of each pCNV diagnosed from CMA was calculated. RESULTS: We included data on 565,708 pregnancies of which 3,982 were diagnosed with a fetal chromosomal aberration (0.70%). cFTS performed well in identifying triploidies (86%), monosomy X (92%), atypical SCAs (58%), and RATs and mosaicisms (70%). pCNVs comprised 28% (n = 1,091) of the chromosomal aberrations diagnosed overall, and the prevalence increased during the study period with more prenatal chromosomal microarray analysis being performed. In pregnancies with maternal age <30 years, NT <95th percentile, PAPP-A MoM ≥ 1, or trisomy 21 risk ≥1 in 1000, the prevalence of pCNVs significantly exceeded the prevalence of trisomies 21, 18, and 13. Pregnancies affected by a pCNV had significantly increased nuchal translucency thickness (NT) and decreased maternal biomarkers pregnancy associated plasma protein-A (PAPP-A) and ß-human chorionic gonadotropin (ß-hCG) compared with unaffected pregnancies. However, only 23% of these pregnancies screened positive from cFTS and 51% were not detected until after birth. Amongst high-risk pregnancies diagnosed with a chromosomal aberration, pCNVs comprised 14% and when other atypical aberrations were considered, conventional NIPT (screening for trisomies 21, 18, and 13, and monosomy X) would miss 28% of all pathogenic aberrations diagnosed following a high-risk cFTS result. Thus, 1 in 26 pregnancies at high-risk following cFTS would be affected by a chromosomal aberration despite a normal conventional NIPT result. In a contingent screening model with NIPT provided for the "intermediate" risk group (T21 risk of 1 in 100-300), 50% of the aberrations would be missed. In our cohort, 80% of the pCNVs diagnosed were <5Mb and therefore not detectable using current forms of "genome wide" NIPT. CONCLUSION: As a by-product to screening for trisomies 21, 18, and 13, most triploidies and the majority of atypical SCAs, RATs, and mosaicisms are detected before birth. However, only 23% of pCNVs are high-risk from cFTS and only half are diagnosed before birth. Replacing invasive testing with NIPT for high-risk pregnancies would substantially decrease the first-trimester detection of pathogenic chromosomal anomalies. This article is protected by copyright. All rights reserved.
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INTRODUCTION: While most melanocytic neoplasms can be classified as either benign or malignant by histopathology alone, ancillary molecular diagnostic tests can be necessary to establish the correct diagnosis in challenging cases. Currently, the detection of copy number variations (CNVs) by fluorescence in situ hybridization and chromosomal microarray (CMA) are the most popular methods, but remain expensive and inaccessible. We aim to develop a relatively inexpensive, fast, and accessible molecular assay to detect CNVs relevant to melanoma using droplet digital polymerase chain reaction (ddPCR) technology. METHODS: In this proof-of-concept study, we evaluated CNVs in MYC and MYB genes from 73 cases of benign nevi, borderline melanocytic lesions, and primary and metastatic melanoma at our institution from 2015 to 2022. A multiplexed ddPCR assay and CMA were performed on each sample, and the results were compared. RESULTS: Concordance analysis of ddPCR with CMA for quantification of MYC and MYB CNVs revealed a sensitivity and specificity of 89% and 86% for MYC and 83% and 74% for MYB, respectively. CONCLUSION: We demonstrate the first use of a multiplexed ddPCR assay to identify CNVs in melanocytic neoplasms. With further improvement and validation, ddPCR may represent a low-cost and rapid tool to aid in the diagnosis of histopathologically ambiguous melanocytic tumors.
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Melanoma , Neoplasias Cutáneas , Humanos , Melanoma/diagnóstico , Melanoma/genética , Variaciones en el Número de Copia de ADN , Hibridación Fluorescente in Situ , Genes myb/genética , Reacción en Cadena de la Polimerasa/métodos , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patologíaRESUMEN
Tetralogy of Fallot (TOF) and double-outlet right ventricle (DORV) are conotruncal defects resulting from disturbances of the second heart field and the neural crest, which can occur as isolated malformations or as part of multiorgan syndromes. Their etiology is multifactorial and characterized by overlapping genetic causes. In this chapter, we present the different genetic alterations underlying the two diseases, which range from chromosomal abnormalities like aneuploidies and structural mutations to rare single nucleotide variations affecting distinct genes. For example, mutations in the cardiac transcription factors NKX2-5, GATA4, and HAND2 have been identified in isolated TOF cases, while mutations of TBX5 and 22q11 deletion, leading to haploinsufficiency of TBX1, cause Holt-Oram and DiGeorge syndrome, respectively. Moreover, genes involved in signaling pathways, laterality determination, and epigenetic mechanisms have also been found mutated in TOF and/or DORV patients. Finally, genome-wide association studies identified common single nucleotide polymorphisms associated with the risk for TOF.
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Ventrículo Derecho con Doble Salida , Tetralogía de Fallot , Humanos , Tetralogía de Fallot/genética , Ventrículo Derecho con Doble Salida/genética , Mutación , Estudio de Asociación del Genoma Completo , Polimorfismo de Nucleótido Simple/genética , Predisposición Genética a la Enfermedad/genética , Factores de Transcripción/genéticaRESUMEN
Defects of situs are associated with complex sets of congenital heart defects in which the normal concordance of asymmetric thoracic and abdominal organs is disturbed. The cellular and molecular mechanisms underlying the formation of the embryonic left-right axis have been investigated extensively in the past decade. This has led to the identification of mutations in at least 33 different genes in humans with heterotaxy and situs defects. Those mutations affect a broad range of molecular components, from transcription factors, signaling molecules, and chromatin modifiers to ciliary proteins. A substantial overlap of these genes is observed with genes associated with other congenital heart diseases such as tetralogy of Fallot and double-outlet right ventricle, d-transposition of the great arteries, and atrioventricular septal defects. In this chapter, we present the broad genetic heterogeneity of situs defects including recent human genomics efforts.
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Mutación , Humanos , Síndrome de Heterotaxia/genética , Cardiopatías Congénitas/genética , Situs Inversus/genéticaRESUMEN
Previous researches revealed a copy number variation (CNV) region in the bovine fibroblast growth factor 13 (FGF13) gene. However, its effects remain unknown. This study detected the various copy number types in seven Chinese cattle breeds and analysed their population genetic characteristics and effects on growth traits and transcription levels. Copy number Loss was more frequent in Caoyuan Red cattle and Xianan cattle than in the other breeds. Association analysis between CNV and growth traits of Qinchuan indicated that the CNV was significantly related to chest depth, hip width and hucklebone width (P < 0.05). Additionally, the growth traits of individuals with copy number Loss were significantly inferior to those with copy number Gain or Median (P < 0.05). Besides, we found two splicing isoforms, AS1 and AS2, in FGF13 gene, which resulted from alternative 5' splicing sites of intron 1. These isoforms showed varied expression levels in various tissues. Moreover, CNV was significantly and negatively associated with the mRNA expression of AS1 (r = -0.525, P < 0.05). The CNVs in bovine FGF13 gene negatively regulated growth traits and gene transcription. These observations provide new insights into bovine FGF13 gene, delivering potentially useful information for future Chinese cattle breeding programs.
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Empalme Alternativo , Variaciones en el Número de Copia de ADN , Factores de Crecimiento de Fibroblastos , Humanos , Animales , Bovinos/genética , Variaciones en el Número de Copia de ADN/genética , Empalme Alternativo/genética , Fenotipo , Isoformas de Proteínas/genéticaRESUMEN
PURPOSE: This study aimed to investigate the correlation between chromosomal abnormalities in spontaneous abortion with clinical features and seek copy number variations (CNVs) and genes that might be connected to spontaneous abortion. METHODS: Over 7 years, we used CNV-seq and STR analysis to study POCs, comparing chromosomal abnormalities with clinical features and identifying critical CNVs and genes associated with spontaneous abortion. RESULTS: Total chromosomal variants in the POCs were identified in 66.8% (2169/3247) of all cases, which included 45.2% (1467/3247) numerical abnormalities and 21.6% (702/3247) copy number variants (CNVs). Chromosome number abnormalities, especially aneuploidy abnormalities, were more pronounced in the group of mothers aged ≥ 35 years, the early miscarriage group, and the chorionic villi group. We further analyzed 212 pathogenic and likely pathogenic CNVs in 146 POCs as well as identified 8 statistically significant SORs through comparison with both a healthy population and a group of non-spontaneously aborted fetuses. Our analysis suggests that these CNVs may play a crucial role in spontaneous abortion. Furthermore, by utilizing the RVIS score and MGI database, we identified 86 genes associated with spontaneous abortion, with particular emphasis on PARP6, ISLR, ULK3, FGFRL1, TBC1D14, SCRIB, and PLEC. CONCLUSION: We found variability in chromosomal abnormalities across clinical features, identifying eight crucial copy number variations (CNVs) and multiple key genes that may be linked to spontaneous abortion. This research enhances the comprehension of genetic factors contributing to spontaneous abortion.
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Aborto Espontáneo , Aberraciones Cromosómicas , Variaciones en el Número de Copia de ADN , Humanos , Femenino , Aborto Espontáneo/genética , Aborto Espontáneo/patología , Variaciones en el Número de Copia de ADN/genética , Embarazo , Adulto , AneuploidiaRESUMEN
OBJECTIVE: To assess the efficacy of copy number variation sequencing (CNV-seq) and karyotyping for prenatal detection of chromosomal abnormalities in fetuses with increased nuchal translucency. METHODS: Amniotic fluid samples were extracted from 205 fetuses with increased nuchal translucency (NT ≥ 2.5 mm), diagnosed by ultrasound between gestational ages of 11 and 13 + 6 weeks. Karyotyping and CNV-seq were performed for detecting chromosomal abnormalities. RESULTS: There are 40 fetuses (19.51%) showing increased NT detected with chromosomal abnormalities in karyotyping, and trisomy 21 was found to be the most common abnormalities. There are 50 fetuses (24.39%) identified with chromosomal abnormalities by CNV-seq. The detection of the applied techniques indicated that CNV-seq revealed higher chromosomal aberrations. The risk of chromosomal abnormalities was significantly increased with NT thickening, from 13.64% in the NT group of 2.5-3.4 mm, 38.64% in the NT group of 3.5-4.4 mm, and to 51.72% in the NT group of over 4.5 mm (P < 0.05). The investigated cases with increased NT with presence of soft markers in ultrasound or high risk in non-invasive prenatal testing presented chromosomal abnormalities in higher rates, comparing with those with isolated NT or low risk (P < 0.05). CONCLUSION: The results indicated that the risk of chromosomal abnormalities was associated with the NT thickness, detected by karyotype or CNV-seq. The combination application of two analysis was efficient to reveal the possible genetic defects in prenatal diagnosis. The finding suggested that the detection should be considered with ultrasonographic soft markers, and the NT thickness of 2.5-3.4 mm could be a critical value for detecting chromosomal abnormalities to prevent the occurrence of missed diagnosis.
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Variaciones en el Número de Copia de ADN , Medida de Translucencia Nucal , Embarazo , Femenino , Humanos , Estudios Retrospectivos , Medida de Translucencia Nucal/métodos , Aberraciones Cromosómicas , Feto , Ultrasonografía PrenatalRESUMEN
Despite the widely accepted involvement of DNA methylation in the regulation of rDNA transcription, the relative participation of different cytosine methylation pathways is currently described only for a few model plants. Using PacBio, Bisulfite, and RNA sequencing; PCR; Southern hybridizations; and FISH, the epigenetic consequences of rDNA copy number variation were estimated in two T. porrifolius lineages, por1 and por2, the latter with more than twice the rDNA copy numbers distributed approximately equally between NORs on chromosomes A and D. The lower rDNA content in por1 correlated with significantly reduced (>90%) sizes of both D-NORs. Moreover, two (L and S) prominent rDNA variants, differing in the repetitive organization of intergenic spacers, were detected in por2, while only the S-rDNA variant was detected in por1. Transcriptional activity of S-rDNA in por1 was associated with secondary constriction of both A-NORs. In contrast, silencing of S-rDNA in por2 was accompanied by condensation of A-NORs, secondary constriction on D-NORs, and L-rDNA transcriptional activity, suggesting (i) bidirectional nucleolar dominance and (ii) association of S-rDNAs with A-NORs and L-rDNAs with D-NORs in T. porrifolius. Each S- and L-rDNA array was formed of several sub-variants differentiating both genetically (specific SNPs) and epigenetically (transcriptional efficiency and cytosine methylation). The most significant correlations between rDNA silencing and methylation were detected for symmetric CWG motifs followed by CG motifs. No correlations were detected for external cytosine in CCGs or asymmetric CHHs, where methylation was rather position-dependent, particularly for AT-rich variants. We conclude that variations in rDNA copy numbers in plant diploids can be accompanied by prompt epigenetic responses to maintain an appropriate number of active rDNAs. The methylation dynamics of CWGs are likely to be the most responsible for regulating silent and active rDNA states.
Asunto(s)
Citosina , Metilación de ADN , ADN Ribosómico , Silenciador del Gen , Citosina/metabolismo , ADN Ribosómico/genética , Variaciones en el Número de Copia de ADN , Transcripción Genética , Epigénesis Genética , Regulación de la Expresión Génica de las Plantas , Cromosomas de las Plantas/genéticaRESUMEN
Recurrent tumor copy number variations (CNVs) in prostate cancer (PrCa) have predominantly been discovered in sporadic tumor cohorts. Here, we examined familial prostate tumors for novel CNVs as prior studies suggest these harbor distinct CNVs. Array comparative genomic hybridization of 12 tumors from an Australian PrCa family, PcTas9, highlighted multiple recurrent CNVs, including amplification of EEF2 (19p13.3) in 100% of tumors. The EEF2 CNV was examined in a further 26 familial and seven sporadic tumors from the Australian cohort and in 494 tumors unselected for family history from The Cancer Genome Atlas (TCGA). EEF2 overexpression was observed in seven PcTas9 tumors, in addition to seven other predominantly familial tumors (ntotal = 34%). EEF2 amplification was only observed in 1.4% of TCGA tumors, however 7.5% harbored an EEF2 deletion. Analysis of genes co-expressed with EEF2 revealed significant upregulation of two genes, ZNF74 and ADSL, and downregulation of PLSCR1 in both EEF2 amplified familial tumors and EEF2 deleted TCGA tumors. Furthermore, in TCGA tumors, EEF2 amplification and deletion were significantly associated with a higher Gleason score. In summary, we identified a novel PrCa CNV that was predominantly amplified in familial tumors and deleted in unselected tumors. Our results provide further evidence that familial tumors harbor distinct CNVs, potentially due to an inherited predisposition, but also suggest that regardless of how EEF2 is dysregulated, a similar set of genes involved in key cancer pathways are impacted. Given the current lack of gene-based biomarkers and clinical targets in PrCa, further investigation of EEF2 is warranted.
Asunto(s)
Síndromes Neoplásicos Hereditarios , Neoplasias de la Próstata , Humanos , Masculino , Australia , Hibridación Genómica Comparativa , Variaciones en el Número de Copia de ADN , Amplificación de Genes , Recurrencia Local de Neoplasia/genética , Síndromes Neoplásicos Hereditarios/genética , Neoplasias de la Próstata/genética , Factores de Elongación de Péptidos/genéticaRESUMEN
In 2004, we started the initial attempt to evaluate the efficacy of SLIT for Japanese cedar pollinosis (JCP) using Japanese cedar (JC) pollen extract solution through a multicenter, placebo-controlled, double-blind comparative study. Based on its success in demonstrating the substantial efficacy of SLIT, we next conducted a larger-scale study by administering JC pollen to all JCP patients recruited. It was because of aiming to ascertain the effectiveness and safety of SLIT and its underlying mechanisms by comparing high- and non-responder patients. Despite limitations posed by liquid medication, significant effectiveness and safety demonstrated by the 2-year treatment served as the foundation for launching the first SLIT medicine for JCP, in 2014. Furthermore, in addition to the clearer Th1/Th2-imbalanced property in the high-responders, the possible involvement of bitter taste receptors in CD4+ T cells, apoptosis pathways in CD4+ T cells and basophils, and inducing a mast cell degranulation inhibitory molecule in the effect of SLIT was demonstrated. To solve the limitations posed by liquid medication, clinical trials evaluating JC pollen sublingual tablets started in 2014. Due to the minimal side effects, ease of administration, and convenient storage, the sublingual tablet medicine was launched in 2018. Giving the ongoing rise in demand for SLIT and considering that more than 1% of JCP patients are currently undergoing SLIT, the practical use of this treatment for multiple allergens is becoming increasingly important.