Search results for "deletion"
showing 10 items of 383 documents
Chromosome 1 abnormalities in myeloid malignancies: a literature survey and karyotype-phenotype associations.
2009
Chromosome 1 is the largest human chromosome and contains over 1600 known genes and 1000 novel coding sequences or transcripts. It is, therefore, not surprising that recurrent chromosome 1 abnormalities are regularly encountered in both neoplastic and non-neoplastic medical conditions. The current review is focused on myeloid malignancies where we summarize the relevant published literature and discuss specific karyotype-phenotype associations. We show that chromosome 1 abnormalities are most frequent in BCR-ABL-negative classic myeloproliferative neoplasms (MPN): polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). Specific abnormalities include duplicat…
Identification of a novel recurrent 1q42.2-1qter deletion in high risk MYCN single copy 11q deleted neuroblastomas
2012
Neuroblastoma is an aggressive embryonal tumor that accounts for similar to 15% of childhood cancer deaths. Hitherto, despite the availability of comprehensive genomic data on DNA copy number changes in neuroblastoma, relatively little is known about the genes driving neuroblastoma tumorigenesis. In this study, high resolution array comparative genome hybridization (CGH) was performed on 188 primary neuroblastoma tumors and 33 neuroblastoma cell lines to search for previously undetected recurrent DNA copy number gains and losses. A new recurrent distal chromosome 1q deletion (del(1)(q42.2qter)) was detected in seven cases. Further analysis of available array CGH datasets revealed 13 additio…
A nonsense mutation abrogates production of a functional enterotoxin A in Clostridium difficile toxinotype VIII strains of serogroups F and X.
1999
Clostridium difficile strains of toxinotype VIII from serogroups F and X are described as toxin B-positive, toxin A-negative (TcdB+ A-), although they harbour almost the entire tcdA gene. To identify the reason for the lack of TcdA detection, we analyzed catalytic and ligand domains of TcdA-1470 of the type strain of serogroup F, strain 1470. Using recombinant fragments, the C-terminal immunodominant ligand domain TcdA3-1470, spanning amino acid residues 1694-2711 (corresponding to VPI 10463 sequence), was detected in Western blots. Similar experiments using the recombinant N-terminal catalytic fragment TcdAc1-2-1470 (amino acid positions 1-544) failed. In addition, this fragment showed no …
Illumina-based RiboMethSeq approach for mapping of 2'-O-Me residues in RNA
2016
International audience; RNA 2'-O-methylation is one of the ubiquitous nucleotide modifications found in many RNA types from Bacteria, Archaea and Eukarya. RNAs bearing 2'-O-methylations show increased resistance to degradation and enhanced stability in helices. While the exact role of each 2'-O-Me residue remained elusive, the catalytic protein Fibrillarin (Nop1 in yeast) responsible for 2'-O-methylation in eukaryotes, is associated with human pathologies. Therefore, there is an urgent need to precisely map and quantify hundreds of 2'-O-Me residues in RNA using high-throughput technologies. Here, we develop a reliable protocol using alkaline fragmentation of total RNA coupled to a commonly …
The loss of the inducible Aspergillus carbonarius MFS transporter MfsA leads to ochratoxin A overproduction
2014
Ochratoxin A (OTA), a nephrotoxic compound produced by certain Aspergillus and Penicillium species, is one of the most abundant mycotoxins in food commodities. Aspergillus carbonarius is the main source of OTA in wine, grape juice and dried vine fruits. Although many studies have focused on OTA production by A. carbonarius, little is known about the genes related to OTA production and transport. We have found a transporter that belongs to the major facilitator superfamily (MfsA) which is highly expressed with a 102-fold induction in an ochratoxigenic A. carbonarius strain compared to a low OTA producer strain. The encoding mfsA gene shows similarity to the multidrug efflux transporter flu1 …
Perfil genómico del neuroblastoma de alto riesgo mediante hibridación genómica comparada
2006
El neuroblastoma presenta alteraciones genéticas que predicen su evolución clínica. Ganancias cromosómicas completas están asociadas a estadios clínicos no avanzados y evolución favorable, mientras que pérdidas de 1p, ganancia de 17q y amplificación del gen MYCN (MNA) son indicativas de estadios clínicos avanzados y pronóstico desfavorable. Son neuroblastomas de alto riesgo (NB-HR) los presentes en niños mayores de un año: estadio 4 o MNA en cualquier estadio de enfermedad, excluyendo estadio 1. El pronóstico de estos enfermos es malo, incluso con tratamientos agresivos. Sólo MNA confiere valor pronóstico negativo. Se remitieron al Centro de Referencia Nacional del neuroblastoma 60 casos de…
Response to lenalidomide in myelodysplastic syndromes with del(5q): influence of cytogenetics and mutations.
2012
Summary Lenalidomide is an effective drug in low-risk myelodysplastic syndromes (MDS) with isolated del(5q), although not all patients respond. Studies have suggested a role for TP53 mutations and karyotype complexity in disease progression and outcome. In order to assess the impact of complex karyotypes on treatment response and disease progression in 52 lenalidomide-treated patients with del(5q) MDS, conventional G-banding cytogenetics (CC), single nucleotide polymorphism array (SNP-A), and genomic sequencing methods were used. SNP-A analysis (with control sample, lymphocytes CD3+, in 30 cases) revealed 5q losses in all cases. Other recurrent abnormalities were infrequent and were not ass…
Myelodysplastic Syndromes with 20q Deletion: Incidence, Prognostic Value and Impact on Response to Azacitidine of ASXL1 Chromosomal Deletion and Gene…
2020
Introduction : The 20q deletion [del(20q)] is a recurrent chromosomal aberration in myelodysplastic syndromes (MDS) and, as a single abnormality, is associated according to the Revised International Prognostic Scoring System (IPSS-R) with a favorable outcome. However, the breakpoint of del(20q) is very heterogeneous and may cause deletion of the ASXL1 gene (20q11.21). This gene is an important epigenetic regulator of hematopoiesis and its mutations have been associated in MDS with a shorter overall survival (OS) and a lower response to azacitidine (AZA). Aim: To assess the incidence, prognostic value and impact on response to AZA of ASXL1 chromosomal alterations and genetic mutations in MDS…
The yeast inositol monophosphatase is a lithium- and sodium-sensitive enzyme encoded by a non-essential gene pair
1999
Inositol monophosphatases (IMPases) are lithium-sensitive enzymes that participate in the inositol cycle of calcium signalling and in inositol biosynthesis. Two open reading frames (YHR046c and YDR287w) with homology to animal and plant IMPases are present in the yeast genome. The two recombinant purified proteins were shown to catalyse inositol-1-phosphate hydrolysis sensitive to lithium and sodium. A double gene disruption had no apparent growth defect and was not auxotroph for inositol. Therefore, lithium effects in yeast cannot be explained by inhibition of IMPases and inositol depletion, as suggested for animal systems. Overexpression of yeast IMPases increased lithium and sodium toler…
Common variants conferring risk of schizophrenia
2009
Schizophrenia is a complex disorder, caused by both genetic and environmental factors and their interactions. Research on pathogenesis has traditionally focused on neurotransmitter systems in the brain, particularly those involving dopamine. Schizophrenia has been considered a separate disease for over a century, but in the absence of clear biological markers, diagnosis has historically been based on signs and symptoms. A fundamental message emerging from genome-wide association studies of copy number variations (CNVs) associated with the disease is that its genetic basis does not necessarily conform to classical nosological disease boundaries. Certain CNVs confer not only high relative ris…