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Le synovialosarcome est une tumeur maligne rare, soit 10% des sarcomes des tissus mous. Il se développe habituellement au niveau des membres et sa localisation pulmonaire est exceptionnelle. Nous rapportons un cas clinique de synovialosarcome du poumon chez un homme de 54 ans découvert à un stade localisé. Cette tumeur, extrêmement rare, présente un phénotype immunohistochimique particulier, qui contribue fortement au diagnostic. L´étude cytogénétique confirme le diagnostic en montrant la présence de la translocation spécifique t (X; 18), qui caractérise le synovialosarcome quelle que soit sa localisation anatomique. À travers cette observation, nous insistons sur les caractéristiques anatomo-cliniques, thérapeutiques et pronostiques de cette tumeur rare souvent méconnue par les cliniciens.

Pulmonary synovial sarcoma is a rare malignant tumor accounting for 10% of soft tissue sarcomas. It usually arises from the limbs and its occurrence in the lung is exceptional. We here report a clinical case of pulmonary synovial sarcoma in a 54-year-old man detected at a localised stage. This extremely rare tumor has a specific immunohistochemical phenotype. This provides strong support for diagnosis. Cytogenetic study confirms the diagnosis by showing the presence of specific translocation t (X; 18). This is highly characteristic of synovial sarcoma regardless of its anatomical location. This study highlights the anatomo-clinical, therapeutic and prognostic characteristics of this rare tumor often unknown to clinicians. [ABSTRACT FROM AUTHOR]

The prognostic evaluation of myelodysplastic syndromes has evolved considerably over time, both due to the evolution of diagnostic classifications and the improvement in the prediction of the outcome. Many prognostic scores that have been developed over time take into account number and depth of blood cytopenias, as well bone marrow blast, cytogenetic, and more recently, molecular mutations. All these variables have been grouped together in IPSS-M score since 2022, which should quickly become a reference for the prognostic evaluation of MDS, as soon as molecular information is available for the patient., (Copyright © 2023 Société Française du Cancer. Published by Elsevier Masson SAS. All rights reserved.)

For commercial oyster aquaculture, triploidy has significant advantages. To produce triploids, the principal technology uses diploid × tetraploid crosses. The development of tetraploid brood stock for this purpose has been successful, but as more is understood about tetraploids, it seems clear that chromosome instability is a principal feature in oysters. This paper is a continuation of work to investigate chromosome instability in polyploid Crassostrea virginica. We established families between tetraploids-apparently stable (non-mosaic) and unstable (mosaic)-and normal reference diploids, creating triploid groups, as well as tetraploids between mosaic and non-mosaic tetraploids. Chromosome loss was about the same for triploid juveniles produced from either mosaic or non-mosaic tetraploids or from either male or female tetraploids. However, there was a statistically significant difference in chromosome loss in tetraploid juveniles produced from mosaic versus non-mosaic parents, with mosaics producing more unstable progeny. These results confirm that chromosome instability, as manifested in mosaic tetraploids, is of little concern for producing triploids, but it is clearly problematic for tetraploid breeding. Concordance between the results from cytogenetics and flow cytometry was also tested for the first time in oysters, by assessing the ploidy of individuals using both techniques. Results between the two were non-concordant. [ABSTRACT FROM AUTHOR]

The genus Eucalyptus L'Herit. is the most cytologically studied group of plants in the family Myrtaceae. Despite the ecological and economic importance of this genus, much of its biology remains poorly understood. Cytological methods are useful in evolutionary studies; however, karyomorphological descriptions of the Eucalyptus species are limited. In this study, we developed a cytogenetic methodology that facilitates karyogram assembly and chromosome classification of Eucalyptus citriodora. The protocol includes treatment of root tips with amiprophos-methyl in Hoagland's solution, slide preparation by cell dissociation, and an air-drying technique. Using this method, well-resolved metaphasic chromosomes with different compaction levels were obtained. A chromosome number of 2n = 22 was confirmed. On the basis of metaphasic chromosomes with limited condensation, E. citriodora showed six metacentric and four submetacentric chromosomes, and one submetacentric chromosome with a nucleolus organizer region (NOR). Thus, the informative chromosomes obtained in this study has enabled the most precise karyotype description of a Eucalyptus species, to date. [ABSTRACT FROM AUTHOR]

Failure of seed production in the genus Arundo L. (Poaceae) is often attributed to polyploidy. This study tested the impact of two ploidy levels ( 2n = 12 and 18 x ) on the fertility of four Mediterranean Arundo. Viable pollen was screened from its production to its germination, and seed occurrence was monitored in admixture or isolated conditions. In addition, insights on restructuration of polyploid genomes were analysed using molecular cytogenetics. Our results show that high ploidy levels do not automatically induce failure of sexual reproduction . The two ploidy levels are able to produce viable pollen and seed set depending on species and cultural conditions. The sterility of A. micrantha ( 2n = 12 x ) and A. donax ( 2n = 18 x ) is due to the early failures of gametogenesis steps. For 18 x cytotypes of A. donaciformis and A. plinii , seed absence for isolated genotype vs. seed production in admixed culture support their auto-incompatibility. [ABSTRACT FROM AUTHOR]

Résumé Le biologiste est en première ligne pour le diagnostic, la classification et le suivi des leucémies aiguës. En ville, l’hémogramme et l’analyse du frottis de sang restent les examens majeurs pour la détection et le suivi d’une leucémie aiguë. En milieu spécialisé, le myélogramme, l’immunophénotypage, les études cytogénétique et moléculaire de la population blastique permettent une sous-classification précise selon les critères actuels de l’OMS 2008, qui conduira à une thérapeutique adaptée et un suivi approprié de la maladie résiduelle. Summary The clinical pathologist is in first line for the diagnosis and follow-up of acute leukemia. In private practice, the complete blood count and the peripheral blood smear examination remain the major tests for the detection and the follow-up of acute leukemia. In specialized institution, bone marrow aspirates, flow cytometry analysis, cytogenetic and molecular studies allow a specific sub-classification according to the WHO 2008, which will lead to an adapted treatment and an appropriate follow-up of residual disease. [ABSTRACT FROM AUTHOR]

In this study we describe the karyotypes and molecular phylogenetic relationships of the leaf frogs Phyllomedusa bahiana Lutz, 1925, Phyllomedusa burmeisteri Boulenger, 1882, Phyllomedusa nordestina Caramaschi, 2006, Phyllomedusa rohdei Mertens, 1926, Phyllomedusa hypochondrialis (Daudin, 1800), and Phasmahyla spectabilis Cruz, Feio and Nascimento, 2008. We analyzed the karyotypes using C-banding, fluorochrome staining, and fluorescence in situ hybridization of telomeric probe, and inferred phylogeny using nuclear tyrosinase and mitochondrial 16S rDNA sequences. Heterochromatin distribution in P. nordestina diverged from the other species, and P. bahiana and P. rohdei showed evident interstitial telomere sequences. Molecular analyzes confirmed the current taxonomic classification, grouping mitochondrial DNA sequences of each species, and usually without haplotype sharing in the nuclear gene. We also extended the distribution of P. burmeisteri to northern Bahia state and restricted P. bahiana to southern Bahia state, with a discrete extension of the range of P. bahiana to the north and northeast of Minas Gerais state. The tyrosinase haplotype network showed a haplotype shared between P. bahiana and P. burmeisteri from Porto Seguro, Bahia. Based on this, we suggest a new distribution in the overlapping area between these two species, which according to our data ranges between Porto Seguro and Camacan, in Bahia state. [ABSTRACT FROM AUTHOR]

Phyllomys (Echimyidae, Rodentia) is a genus of Neotropical rodents with available cytogenetic data restricted to six out of 13 species, mainly based on simple staining methods, without detailed analyses. In this work, we present new karyotypes for Phyllomys lamarum (diploid number 2 n = 56, fundamental number or number of autosomal arms FN = 102) and Phyllomys sp. (2 n = 74, FN = 140) from the state of Minas Gerais, southeastern Brazil. We provide the first GTG- and CBG-banding patterns, silver-staining of the nucleolar organizer regions (Ag-NORs), and fluorescence in situ hybridization (FISH) with telomeric and 45S rDNA probes of Phyllomys. In addition to examining their chromosomes and phenotypic characters, we sequenced mitochondrial DNA from the specimens analyzed to confirm their taxonomic identification. The comparison of the distinctive chromosome complements of our specimens with those of other species of Phyllomys already published allowed us to conclude that chromosome data may be very useful for the taxonomy of the genus, as no two species analyzed presented the same diploid and fundamental numbers (2 n and FN). [ABSTRACT FROM AUTHOR]

Résumé: L’histoire des lymphomes et de leurs classifications commence au XIXe siècle, avec la description des premières maladies par les pionniers de la méthode anatomo-clinique : tels que Hodgkin, Virchow, Ewing… Durant le XXe siècle jusqu’à nos jours, les classifications des lymphomes deviennent de plus en plus élaborées et consensuelles alors que les critères morphologiques seront complétés par un colossal travail multidisciplinaire incluant des données cliniques, immuno-histochimiques, cytogénétiques, génotypiques, bioinformatiques et bio-statistiques. Les progrès de la science ainsi que de la médecine qui devient «fondée sur les faits » aboutissent à une compréhension accrue et une prise en charge améliorée des patients. Les classifications successives mises au point pour décrire les lymphomes sont le reflet de l’état des connaissances et des techniques en hématologie, immunologie, génétique et en imagerie microscopique d’une époque donnée. La première nomenclature historique des leucémies et lymphomes publiée en 1903 tenait en quatre petits groupes de mots et celle du « livre bleu » de l’OMS 2008 est un référentiel de 439 pages incluant 2510 références. Cet ouvrage regroupe un vaste ensemble structuré de données multifactorielles susceptibles d’aboutir à l’élaboration de nouvelles thérapies ciblées. En survolant chronologiquement les principales classifications de lymphomes, nous tentons d’extraire pour chaque période un paradigme dominant qui sert de fil conducteur à la pensée de l’époque et permet de construire un modèle hiérarchisé de connaissance qui s’enrichit et se consolide au fur et à mesure que la science et la médecine progressent. [Copyright &y& Elsevier]

The cytogenetic characteristics of 17 species of bushcricket belonging to eight genera of the tribe Barbitistini were examined by fluorescence in situ hybridization with 18S rDNA and (TTAGG n) telomeric as probes and by C-banding, silver, and fluorochrome staining. These markers were used to understand chromosomal organization and evolutionary relationships between genera or species within the same genus. The number of 18S rDNA clusters per haploid genome that co-localized with active nucleolus organizer regions (NORs) ranged from one to five, with the most common pattern being the presence of one NOR-bearing chromosome. This ribosomal cistron was preferentially located in the paracentromeric region of autosomes and very rarely in the sex chromosome. The results demonstrated coincidence between the localization of major ribosomal genes and active NORs and the position of C-band and GC-rich regions. The rDNA/NOR distribution and the composition of chromosome heterochromatin proved to be good cytogenetic markers for distinguishing species and phylogenetic lines and for understanding the genomic differentiation and evolution of Barbitistini. A comparison of cytogenetic and morphological or behavioral traits suggests that morphological and behavioral specialization in this group was not followed by major karyotype modification (except for Leptophyes). However, the occurrence and distribution of different repetitive DNA sites tends to vary among the taxa. [ABSTRACT FROM AUTHOR]

Résumé: La LLC typique constitue le principal diagnostic des lymphocytoses de l’adulte. Si l’examen du frottis sanguin peut permettre à lui seul d’en proposer le diagnostic, il existe néanmoins des LLC cytologiquement et parfois immunologiquement atypiques qui posent un problème de diagnostic différentiel avec les disséminations sanguines des lymphomes à petites cellules B, en particulier avec le lymphome splénique des cellules de la zone marginale, parfois le lymphome des cellules du manteau et plus rarement le lymphome folliculaire. Si dans ces cas de cytologie difficile, une analyse précise du frottis sanguin peut orienter le diagnostic, celui-ci devra être confirmé par les investigations complémentaires que sont l’immunophénotypage par cytométrie en flux (CMF) et l’analyse en cytogénétique conventionnelle ou moléculaire, telles que les techniques d’hybridation in situ (FISH), associées aux autres paramètres clinico-biologiques. Dans le but d’optimiser la démarche diagnostique le rôle de l’expertise cytologique reste néanmoins primordial permettant d’orienter le choix du panel d’anticorps utilisé en CMF et celui des sondes fluorescentes utilisées en FISH. En conclusion, devant toute lymphocytose, l’examen cytologique attentif du frottis sanguin doit rester à la base ou à la première étape du diagnostic, et s’il est suffisamment informatif dans la LLC typique, le diagnostic précis doit être pluridisciplinaire (morphologique, immunologique, cytogénétique et moléculaire) dans les formes plus atypiques. [Copyright &y& Elsevier]

Résumé: Les syndromes lymphoprolifératifs chroniques matures B regroupent un grand nombre d’hémopathies clonales avec des caractéristiques cliniques, biologiques, histologiques et génétiques variées. Le diagnostic repose essentiellement sur l’aspect morphologique et la présence de marqueurs de membrane détectés en cytométrie en flux, cependant il existe des formes frontières ou atypiques nécessitant une caractérisation génétique complémentaire. La cytogénétique et la biologie moléculaire sont des techniques complémentaires pour l’aide au diagnostic dans ces cas. Dans le cas très particulier de la leucémie lymphoïde chronique (LLC), ces outils aident à classer les patients dans des groupes pronostiques afin de déterminer les meilleures stratégies thérapeutiques. Dans cet article, nous présentons en premier, les intérêts de la cytogénétique et de la biologie moléculaire comme aide au diagnostic des hémopathies lymphoïdes. Dans une seconde partie, nous présentons l’apport de la cytogénétique et de la biologie moléculaire dans l’identification de facteurs pronostiques dans la LLC, en particulier le statut mutationnel des gènes des immunoglobulines, les mutations de TP53 et la détection des anomalies cytogénétiques par hybridation in situ en fluorescence (FISH). [Copyright &y& Elsevier]

Abstract: Fanconi anemia (FA) is a recessive chromosomal instability syndrome that is clinically characterized by multiple symptoms. Chromosome breakage hypersensitivity to alkylating agents is the gold standard test for FA diagnosis. In this study, we provide a detailed laboratory protocol for accurate assessment of FA diagnosis based on mitomycin C (MMC) test. Induced chromosomal breakage study was successful in 171 out of 205 aplastic anemia (AA) patients. According to the sensitivity of MMC at 50ng/ml, 38 patients (22.22%) were diagnosed as affected and 132 patients (77.17%) as unaffected. Somatic mosaicism was suspected in an 11-year-old patient with a FA phenotype. Twenty-six siblings of FA patients were also evaluated and five of them (19.23%) were diagnosed as FA. From this study, a standard protocol for diagnosis of FA was developed. It is routinely used as a diagnostic test of FA in Tunisia. [Copyright &y& Elsevier]

Abstract: The specific identification and systematic of triatomines have been based fundamentally on morphological observations. These organisms are classified into complexes and specific subcomplexes, principally for morphological parameters and geographical disposition. The use of cytogenetic analyzes has been represented as a tool in systematic and taxonomy of triatomines. Thus, the present work, through the analysis of spermiogenesis, aims to characterize this stage of spermatogenesis in triatomines little studied, and especially to compare it among the species Triatoma lenti and T. sherlocki, to assist in the diagnosis of differentiation of these insects. The presence of the heteropyknotic corpuscle is shown as a diagnostic tool to differentiate T. sherlocki and T. lenti, since it is absent in T. lenti. The analysis of the spermiogenesis in T. sherlocki also allowed us to address morphological differences between elongating cells, which were relatively smaller and more filamentous when compared to T lenti. Furthermore, the flagellum was observed in all stages of cell differentiation and elongation. This structure, which helps in the locomotion of the sperm, is hardly observed in cytogenetic analysis, especially throughout spermiogenesis. Thus, although other comparative approaches should be taken, this paper allowed emphasizing the analysis of spermiogenesis as an important cytotaxonomic tool that assists in the differentiation of morphologically related species, such as T. lenti and T. sherlocki. [Copyright &y& Elsevier]

In these last years of revolutionary tyrosine kinase inhibitor treatments, patients with chronic myeloid leukemia are most commonly monitored by regular examination of bone marrow and peripheral blood in order to assess the quality of the response to treatment. Biological criteria and adapted methodologies in cytogenetics and molecular biology have been established from clinical trials. To date, it is essential to know these criteria for an optimal therapeutic management of these patients, in order to guarantee a better overall survival and an event-free survival. [ABSTRACT FROM AUTHOR]

Interspecific hybridization in Tecoma Juss. was conducted to develop novel forms for the nursery industry. We report fertile hybrids from the cross T. garrocha Hieron. (pistillate parent) × T. stans (L.) Juss. ex Kunth. Leaf morphology of the F1 hybrids of T. garrocha × T. stans was intermediate between the parents. GISH also confirmed hybridity. The F1 hybrids were successfully backcrossed to both parents and self-pollinated to produce BC and F2 progeny. Tecoma garrocha, T. stans, and T. guarume A. DC. 'Tangelo' were self-fertile. The F1 hybrids also were crossed with T. capensis (Thunb.) Lindl. and T. guarume 'Tangelo', resulting in three-species hybrids. FISH conducted on F1 hybrids identified four copies of the 18S internal transcribed spacer region. Further analysis using FISH has the potential to provide information on the evolution of Bignoniaceae and the potential role of polyploidy. [ABSTRACT FROM AUTHOR]

An integrated approach based on cytogenetics, molecular genetics, and ecology was used to examine diversity in the black fly Simulium angulistylum Takaoka & Davies in Thailand. Cytological analysis revealed three cytoforms (A, B, and C) of S. angulistylum differentiated by fixed chromosome inversions. Distributions of these cytoforms were associated with ecology. Cytoforms A and B were found in low-altitude habitats (<600 m above sea level), whereas cytoform C occurred at high altitudes (>1000 m above sea level). Mitochondrial DNA sequences of the cytochrome oxidase subunit I barcoding region revealed significant genetic differentiation among the cytoforms. The mitochondrial DNA haplotype network revealed divergent lineages within cytoforms, indicating additional hidden diversity. Therefore, integrated approaches are necessary for fully understanding black fly biodiversity. Population genetic analysis revealed high genetic structuring that could be due to the habitat preferences of S. angulistylum. Phylogeographic analyses indicated population demographic expansion at the mid-Pleistocene (900 000 years ago), which is older than for other black flies and insects in the Southeast Asian mainland. The high level of genetic structure and diversity, therefore, could also be due to the long demographic history of S. angulistylum. [ABSTRACT FROM AUTHOR]

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Copyright of Journal Africain D'Hépato-Gastroentérologie is the property of Lavoisier and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article discusses the component of the plant Arabidopsis thaliana. It notes that the plant which is a member of the brassicaceae family has a plastic component called heterochromatin. It describes heterochromatin as a large fraction of active eurochromatin that contain heterochromatic sequences.

The Brassica B-genome species possess many valuable agronomic and disease resistance traits. To transfer traits from the B genome of B. carinata into B. napus, an interspecific cross between B. napus and B. carinata was performed and a doubled haploid (DH) population was generated from the BC2S3 generation. Successful production of interspecific DH lines as identified using B-genome microsatellite markers is reported. Five percent of DH lines carry either intact B-genome chromosomes or chromosomes that have deletions. All of the DH lines have linkage group J13/B7 in common. This was further confirmed using B. nigra genomic DNA in a fluorescent in situ hybridization assay where the B-genome chromosomes were visualized and distinguished from the A- and C-genome chromosomes. The 60 DH lines were also evaluated for morphological traits in the field for two seasons and were tested for resistance to blackleg, caused by Leptosphaeria maculans, under greenhouse conditions. Variation in the DH population followed a normal distribution for several agronomic traits and response to blackleg. The lines with B-genome chromosomes were significantly different (p < 0.01) from the lines without B-genome chromosomes for both morphological and seed quality traits such as days to flowering, days to maturity, and erucic acid content. [ABSTRACT FROM AUTHOR]

Copyright of African Journal of Cancer / Journal Africain du Cancer is the property of Lavoisier and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of African Journal of Cancer / Journal Africain du Cancer is the property of Lavoisier and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Andrologie (11662654) is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ginecología y Obstetricia de México is the property of Federacion Mexicana de Ginecologia y Obstetricia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Waldenström macroglobulinemia (WM) is now defined as an uncommon lymphoplasmocytic proliferation associated with an immunoglobulin M peak. The associated chromosomal abnormalities are not specific to the disease, and changes in the diagnostic criteria and techniques used as well as low-level abnormal cell proliferation made their analysis difficult. A literature review however, shows that if specific abnormalities were not recognized until now, it is the frequency of some chromosomal abnormalities (for instance partial deletion of the long arm of chromosome 6 and trisomy 4) that distinguishes WM from other chronic malignant B-cell proliferations. The data collected in the present review show directions for future research which will benefit from use of more recent techniques such as fluorescent in situ hybridization, comparative genomic hybridization and expression microarrays. [Copyright &y& Elsevier]

The SalI satellite repeat previously identified in Haliotis L. (abalone) was thought to be present in H. rufescens and absent in H. fulgens. However, we show here that SalI is also found in H. fulgens and is not useful for screening hybrid individuals bred in aquaculture or occurring naturally in the wild. SalI is a family of predominantly subtelomeric tandemly repeated sequences, and sequenced clones revealed clustering to species and little intraspecific variation. Analysis of SalI sequence divergence between Haliotis species of the Northeast Pacific revealed that evolutionary distances correlate well with bathymetric and latitudinal species distributions. Analysis of the structure of the tandem repeats revealed two regions of high sequence conservation that may contain conserved transcription factor binding sites, a surprise for an apparently “non-coding” tandem repeat. We speculate that these regions might be involved in heterochromatin silencing, perhaps mediated via transcriptional activity and RNA interference. The repeats show substantial differences in their chromosomal distributions, even between individuals of the same species, indicating a dynamic organization of repeats, perhaps mediated via sequence homogenization. L’ADN satellite SalI identifié antérieurement chez le Haliotis L. (ormeau nordique) était présumé présent chez le H. rufescens et absent chez le H. fulgens. Les auteurs montrent ici que le satellite SalI est également présent chez le H. fulgens et n’est donc pas utile pour identifier des hybrides produits en aquaculture ou survenant naturellement. Le satellite SalI est une séquence répétée principalement subtélomérique et les clones séquencés suggèrent un groupement sur la base des espèces et peu de variation intraspécifique. L’analyse de la divergence nucléotidique entre les espèces de l’Haliotis du nord-est du Pacifique a révélé que les distances évolutives sont bien corrélées avec la répartition latitudinale et bathymétrique des espèces. L’analyse de la structure des répétitions en tandem révèle deux régions de forte conservation des séquences qui pourraient contenir des sites conservés de liaison de facteurs de transcription, une observation surprenante au sein d’une région apparemment « non-codante ». Les auteurs spéculent que ces régions sont peut-être impliquées dans l’inactivation de l’hétérochromatine obtenue via l’activité transcriptionnelle et l’interférence à l’ARN. Les répétitions affichent des différences substantielles dans leur distribution chromosomique, même entre individus de la même espèce ce qui indique une organisation dynamique des répétitions, peut-être via l’homogénéisation des séquences. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: Recent development of interphase fluorescence in situ hybridization (FISH) allows analysis on non-proliferant plasma cells. We describe the most frequent genetic abnormalities in multiple myeloma and their prognostic value. Current knowledge and key points: Most frequent genetic abnormalities are illegitimate rearrangements involving the IGH gene at 14q32 (60% of patients), hyperdiploidy (50 to 60% of patients), chromosome 13 deletion (40 to –50% of patients), chromosome 1q gain (30 to –40% of patients) chromosome 17 deletion (10% of patients). Some of these genetics abnormalities are observed in monoclonal gammopathy of undetermined significance (MGUS) a pre-malignant state. t(4;14) and t(14;16) translocations and chromosome 17 deletion negatively impact the overall survival. Patients with these genomic aberrations should be treated with specific treatment. Future prospects and projects: Identification of genetic abnormalities is important for evaluation of prognosis and treatment protocol in multiple myeloma. [Copyright &y& Elsevier]

In an earlier study, the progenies of intergeneric hybrids Brassica napus (2n = 38) × Orychophragmus violaceus (2n = 24) were investigated in successive generations (F1–F4) for the cytological phenomenon of parental genome separation during mitotic and meiotic division. In the present study, inbred lines (F5–F8) derived from 1 such hybrid were characterized for morphology, chromosome pairing behaviour, and genome composition. One F5 plant (2n = 31) with slightly yellow petals and 12:19 and 15:16 segregation ratios in its pollen mother cells (PMCs) produced F6 plants with distinct morphological characteristics and wide variations in fertility and chromosome numbers (2n = 25–38). F7 and F8 lines with distinctive morphology and wide ranges in chromsome numbers were established. In PMCs of F7 plants from 4 F6 plants, 0–12 labelled chromosomes from O. violaceus, which predominantly appeared as bivalents, were identified by genomic in situ hybridization. They behaved synchronously with B. napus chromosomes during meiotic division. The results provide molecular cytogenetic evidence of the inclusion of O. violaceus chromosomes in the original hybrids and the cytology in the hybrids documented earlier. They also show that chromosome behaviour was altered and the parental chromosomes became synchronized after successive generations. [ABSTRACT FROM AUTHOR]

Abstract: Myelofibrosis with myeloid metaplasia (MMM) is a rare myeloproliferative disorder (MPD) characterized by clonal proliferation of hematopoietic progenitors. 40–50% of karyotypes on blood (or more rarely on bone marrow) revealed at least one abnormality: 30% at diagnosis and 90% in blastic transformation phase. A minority of patients with newly diagnosed polycythemia vera (PV) presented chromosomal abnormalities in their myeloid cells. The most frequent visible alteration in MMM and PV is a 20q deletion, also characterized in other MPDs and myeloid malignancies. Among other chromosomal changes, deletion 13q is more common in MMM than in other MPDs, trisomy 9 and 9p alterations appear more frequent in PV. Cytogenetic studies have disclosed cryptic anomalies and pointed out the high frequency of 9p alterations. JAK2 (V617F) mutation was found in almost all PV patients and near half of MMM patients. This molecular abnormality takes an increased importance in the knowledge of the physiopathology of MPDs, particularly in PV and also in prognosis of MMM patients. [Copyright &y& Elsevier]

Abstract: Chromosomal aberrations are the first cause of mental impairment and dysmorphism. Rearrangements involving large chromosomal segments can be detected by standard chromosome analysis using GTG-banding, but this technique is not suited for the detection of small chromosome abnormalities. Array comparative genomic hybridisation (array-CGH) is a method used to detect segmental DNA copy number alterations. Recently, advances in this technology have enabled high-resolution examination for identifying genetic alterations and copy number variations on a genome-wide scale. This review describes the current genomic array platforms and CGH methodologies and highlights their applications for studying constitutional disease. [Copyright &y& Elsevier]

Abstract: The correct enumeration of human chromosomes, only established in 1956, has marked the starting point of the modern cytogenetics. The introduction of banding techniques, then of in situ hybridization techniques, and now of genomic microarray technology allowed a dramatic development of cytogenetics of which the main applications to basic and medical research are evoked in this review. [Copyright &y& Elsevier]

Follicular lymphoma is the second most frequent lymphoma entity. Its main features are well known in morphology, immunology and genetics. Lymphoma cells carry the t(14;18)(q32 ; q21) translocation, which rearranges the BCL2 gene and protects them against apoptosis. Detection of this molecular abnormality for diagnosis and therapy evaluation still appears difficult to interpret. Recent data provided by gene expression profiling experiments underline the role of tumour microenvironment in follicular lymphoma: the presence of specific immune cells in the lymph node may contribute to the disease aggressiveness. These data help to reexamine various models for the understanding of lymphoma development, while new therapeutic options are improving the prognosis of the patients. [ABSTRACT FROM AUTHOR]

The B chromosome of maize undergoes frequent non-disjunction at the second pollen mitosis. In B–A translocations, the B–A chromosome retains the capacity for non-disjunction. We have collected deletion-derivative TB-9Sb stocks. One derivative, the "type 1 telocentric", has a B–9 chromosome that lacks centric heterochromatin. It produces few recessive (non-disjunctional) phenotypes in pollen parent testcrosses of the translocation heterozygote, 9 9–B telo B–9. The finding helped demonstrate the role of centric heterochromatin in non-disjunction. An isochromo some derivative of the type 1 telocentric was also recovered. It was tested in the 9–B 9–B iso B–9 constitution. This is equivalent to 9 9–B telo B–9 in terms of chromosome 9 dosage. Surprisingly, crosses with the isochromosome gave significant levels of recessive phenotypes. In addition, high levels of variegated phenotypes were found. Recently, a circumstance was found that makes inheritance of the type 1 telocentric chromosome somewhat similar to that of the isochromosome. Crosses with hypoploid 9–B 9–B telo B–9 plants showed significant levels of recessive and variegated phenotypes. These crosses were investigated to help explain the source(s) of the phenotypes. Cytological and genetic studies were performed. Centric misdivision was found to account for the variegated phenotypes. A mixture of conventional B non-disjunction and centric misdivision produced the recessive phenotypes. The significance of conventional non-disjunction in the absence of centric heterochromatin is discussed. [ABSTRACT FROM AUTHOR]

In this review, we combine the results of our published and unpublished work with the published results of other laboratories to provide an updated map of the centromeric heterochromatin of chromosome 3 in Drosophila melanogaster. To date, we can identify more than 20 genes (defined DNA sequences with well-characterized functions and (or) defined genetic complementation groups), including at least 16 essential loci. With the ongoing emergence of data from genetic, cytological, and genome sequencing studies, we anticipate continued, substantial progress towards understanding the function, structure, and evolution of centric heterochromatin. [ABSTRACT FROM AUTHOR]