Search results for "Germline"

The Clinical Significance of Unknown Sequence Variants in BRCA Genes.

2010

Abstract: Germline mutations in BRCA1/2 genes are responsible for a large proportion of hereditary breast and/or ovarian cancers. Many highly penetrant predisposition alleles have been identified and include frameshift or nonsense mutations that lead to the translation of a truncated protein. Other alleles contain missense mutations, which result in amino acid substitution and intronic variants with splicing effect. The discovery of variants of uncertain/unclassified significance (VUS) is a result that can complicate rather than improve the risk assessment process. VUSs are mainly missense mutations, but also include a number of intronic variants and in-frame deletions and insertions. Over …

The von Hippel-Lindau tumor suppressor gene

1997

Abstract The von Hippel-Lindau (VHL) disease is an inherited tumor susceptibility syndrome featuring a high variety of benign and malignant tumors. The gene has been localized and cloned at 3p25-26. Recent functional analysis defined the VHL gene product as an inhibitor of the transcription elongation process. Its possible involvement in the vascularization process may explain the histologic features of VHL tumors providing insight into basic mechanism of tumorigenesis. Direct genetic testing is available for patients affected with VHL. Seventy to eighty percent of the germline mutations expected could be detected. As first geno/phenotype correlations have been established, we are now begin…

Next generation sequencing of HCC from European and Asian HCC cohorts. Back to p53 and Wnt/β-catenin

2013

Hepatocellular carcinoma (HCC) is the most common pri- mary liver malignancy. Here, we performed high-resolution copy- number analysis on 125 HCC tumors and whole-exome sequencing on 24 of these tumors. We identified 135 homozygous deletions and 994 somatic mutations of genes with predicted functional conse- quences. We found new recurrent alterations in four genes (ARID1A, RPS6KA3, NFE2L2 and IRF2) not previously described in HCC. Func- tional analyses showed tumor suppressor properties for IRF2, whose inactivation, exclusively found in hepatitis B virus (HBV)-related tumors, led to impaired TP53 function. In contrast, inactivation of chromatin remodelers was frequent and predominant in al…

Histone-mediated transgenerational epigenetics

2019

Abstract Epigenetic mechanisms operate at the interface between the environment and genome, by converting the environmental stimuli to phenotypic responses through changes in the chromatin landscape, which ultimately affects gene expression in the absence of alterations in DNA sequence. In this scenario, transgenerational inheritance occurs when epigenetic variations induced by environmental stimuli are transmitted through the germ line to succeeding generations that had never experienced those stimuli. There is an ever-growing list of reports indicating that histones are fundamental players in these processes in a variety of organisms. In this chapter, we provide a perspective on histone-d…

Distinctive Patterns of Intraclonal Diversification In IGHV1-2*04 Immunoglobulin Receptors of Patients with Splenic Marginal Zone Lymphoma: A of Ongo…

2011

Abstract Abstract 2638 We recently demonstrated that over 30% of cases with splenic marginal-zone lymphoma (SMZL) express distinctive immunoglobulin (IG) receptors that utilize a single polymorphic variant of the IGHV1-2 gene (IGHV1-2*04) and also exhibit restricted antigen-binding site motifs and precise targeting of somatic hypermutation (SHM). On these grounds, we proposed the existence of molecular subtypes of SMZL defined by immunogenetic analysis of the IG receptors with implications for selection by specific (super) antigenic element(s) in the development of at least a major subset of SMZL. In order to gain insight as to whether antigen involvement is relevant only prior to the malig…

Hereditary Cancers and Genetics

2021

The study of hereditary syndromes is fundamentally based on the finding and identification of susceptibility genes underlying the pathology. Although hereditary tumors account for only a small fraction of all the tumors, the knowledge of underlying genetics changed the clinical management of affected patients and their families, also providing important information on the molecular mechanisms involved in the development of sporadic tumors. In the subjects who inherit a germline mutation, all the cells of the organism are carriers of that mutation, predisposing such subject to develop neoplasm more easily and earlier compared to the general population. The identification of individuals with …

Mutational analysis ofBRCA1andBRCA2in Mediterranean Spanish women with early-onset breast cancer: Identification of three novel pathogenic mutations

2003

In Spain, the contribution of BRCA mutations to the population incidence of early-onset breast cancer was unknown. We carried out a mutational analysis of the BRCA1 and BRCA2 genes in 124 Spanish women diagnosed with breast cancer before the age 41 and who were not selected for a family history of this disease. The genetic study was performed by PCR-SSCP analysis and DNA sequencing. We identified 6 pathogenic BRCA mutations in 7 unrelated probands (5.6%; 95% CI=2.3% to 11.3%): 1 BRCA1 (c.2080delA) and 5 BRCA2 (p.Y3006X, p.Q1994X, c.9204_9217del14, c.9254_9258del5 and c.295+2T>C). Three out of 6 mutations were novel (BRCA2 p.Y3006X, c.9204_9217del14, and c.295+2T>C), and two further mutation…

Analysis ofBRCA1andBRCA2genes in Spanish breast/ovarian cancer patients: A high proportion of mutations unique to Spain and evidence of founder effec…

2003

We screened index cases from 410 Spanish breast/ovarian cancer families and 214 patients (19 of them males) with breast cancer for germ-line mutations in the BRCA1 and BRCA2 genes, using SSCP, PTT, CSGE, DGGE, and direct sequencing. We identified 60 mutations in BRCA1 and 53 in BRCA2. Of the 53 distinct mutations observed, 11 are novel and 12 have been reported only in Spanish families (41.5%). The prevalence of mutations in this set of families was 26.3%, but the percentage was higher in the families with breast and ovarian cancer (52.1%). The lowest proportion of mutations was found in the site-specific female breast cancer families (15.4%). Of the families with male breast cancer cases, …

162P Prevalence and spectrum analysis of germline BRCA1 and BRCA2 variants of unclear significance in HBOC Syndrome: Decoding the mysterious signals …

2021

Pathogenic DDX3X mutations impair RNA metabolism and neurogenesis during fetal cortical development

2018

AbstractDe novo germline mutations in the RNA helicase DDX3X account for 1-3% of unexplained intellectual disability (ID) cases in females, and are associated with autism, brain malformations, and epilepsy. Yet, the developmental and molecular mechanisms by which DDX3X mutations impair brain function are unknown. Here we use human and mouse genetics, and cell biological and biochemical approaches to elucidate mechanisms by which pathogenic DDX3X variants disrupt brain development. We report the largest clinical cohort to date with DDX3X mutations (n=78), demonstrating a striking correlation between recurrent dominant missense mutations, polymicrogyria, and the most severe clinical outcomes.…