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Corn is the second most cultivated crop in Brazil, the number-one country in pesticide consumption. Chemical control of weeds is performed using herbicides such as S-metolachlor with pre- and post-emergence action and thus the toxicity of herbicides constitutes a matter of great concern. The present investigation aimed to examine the effects of an S-metolachlor-based herbicide on Lactuca sativa L. (lettuce) and Zea mays L. (maize) utilizing various bioassays. The test solutions were prepared from commercial products containing the active ingredient. Seeds from the plant models were exposed in petri dishes and maintained under biochemical oxygen demand (BOD) at 24°C. Distilled water was negative and aluminium positive control. Macroscopic analyses (germination and growth) were conducted for both plant species, and microscopic analysis (cell cycle and chromosomal alterations) were performed for L. sativa root tip cells. Detrimental interference of S-metolachlor-based herbicide was noted with lettuce for all parameters tested reducing plant germination by over 50% and the germination speed by over 45% and showing a significant decrease in mitotic index, from 16.25% to 9,28% even on the lowest concentration tested. In maize, there was no significant interference in plant germination; however, speed of germination was significantly hampered, reaching a 51.22% reduction for the highest concentration tested. Data demonstrated that the herbicide was toxic as evidenced by its phyto- and cytotoxicity in L. sativa L. and Z. mays L. [ABSTRACT FROM AUTHOR]

Sex chromosomes have evolved in many plant species with separate sexes. Current plant research is shifting from examining the structure of sex chromosomes to exploring their functional aspects. New studies are progressively unveiling the specific genetic and epigenetic mechanisms responsible for shaping distinct sexes in plants. While the fundamental methods of molecular biology and genomics are generally employed for the analysis of sex chromosomes, it is often necessary to modify classical procedures not only to simplify and expedite analyses but sometimes to make them possible at all. In this review, we demonstrate how, at the level of structural and functional genetics, cytogenetics, and bioinformatics, it is essential to adapt established procedures for sex chromosome analysis. [ABSTRACT FROM AUTHOR]

Summary Monoclonal Immunoglobulin deposition disease (MIDD) is characterised by deposits of intact monoclonal light chains in the kidney leading to renal dysfunction. In this study, we retrospectively investigated the underlying plasma cell cytogenetic abnormalities in MIDD. CyclinD1 (11;14) translocation was identified in 12/27 (45%) patients. Among the patients without translocation, del13q and hyperdiploidy were the most common abnormalities. Patients in the non‐t (11;14) group had a higher baseline light‐chain ratio, higher proteinuria and lower eGFR as compared to patients with t (11;14). Haematological VGPR or higher was seen in 58% of t (11;14), and 30% without t (11;14), possibly related to higher use of Daratumumab‐based therapy in the t (11;14) group. With a median follow‐up of 750 days, 30% (8/24) progressed to end stage renal disease (ESRD). eGFR <20 mL/min (HR 25, 95% CI 2.09–298, p = 0.01) and 24 urine protein >3 g/24 h (HR 9, 95% CI 1.27–63.90, p = 0.02) at diagnosis were significantly associated with progression to ESRD. Renal survival was better in t (11;14) as compared to the non‐t (11;14) group (HR 0.11, p = 0.06). Translocation (11;14) is a common abnormality in MIDD and affects the presentation and outcomes. Identification of this abnormality should lead to exploration of BCL2 inhibitors in this disease. [ABSTRACT FROM AUTHOR]

Simple Summary: Sex chromosomal abnormalities are a major cause of reproductive failure in horses. While some horses with abnormal karyotypes exhibit reproductive abnormalities, others appear normal, remaining misdiagnosed until late age. The Pura Raza Español breeding program screens all horses for these abnormalities using genomics before adding them to the studbook. This process includes an initial assessment using the results of Short Tandem Repeat (STR) parentage testing, followed by confirmation using Single-Nucleotide Polymorphism (SNP) analysis for copy number aberrations. Hereby, we identified five new cases of 65,XXY syndrome among 27,330 foals over two breeding seasons. These horses were flagged as possibly affected by a chromosomal number aberration (CNA) due to abnormal STR and confirmed as 65,XXY by genomic analysis. All of them showed a male phenotype. One horse showed abnormal gonad development, whereas the others did not have visible abnormalities. This study represents the largest group of horses diagnosed with 65,XXY and emphasizes the importance of genomic screening for chromosomal testing. Sex chromosomal abnormalities are a well-established cause of reproductive failure in domestic horses. Because of its difficult diagnosis, the Pura Raza Español breeding program established a routine screening for chromosomal abnormalities in all the horses prior to enrolling in the studbook. This genomic procedure combines an initial assessment based on the results from Short Tandem Repeat (STR) parentage testing followed by a Single-Nucleotide Polymorphism (SNP) based copy number aberration (CNA) confirmative analysis in positive cases. Using this methodology, we identified five new individuals carrying a 65,XXY chromosomal number aberration (CNA) among 27,330 foals enrolled over the past two reproductive seasons. The animals were initially flagged as CNA candidates due to abnormal results in STR testing. Subsequent analysis genotyping using an STR sex-linked dedicated panel and a medium-density SNP array in ECAX and ECAY confirmed the diagnosis as 65,XXY carriers. Four cases (upon sample availability) underwent further analysis using in situ fluorescent hybridization with ECAX and ECAY probes, showing identical results. Phenotypic analysis revealed abnormal gonad development in one of the cases, showing that the remaining four had a normal reproductive morphology. To our knowledge, this represents the largest number of horses exhibiting the equine form of Klinefelter syndrome (65,XXY) reported to date. Our study highlights the importance of genomic screening in the accurate detection of chromosomal abnormalities in horses. [ABSTRACT FROM AUTHOR]

Simple Summary: Azacytidine and donor lymphocyte infusions were combined effectively in a single-center high-risk patient cohort (n = 29) for post-transplant relapse of acute myeloid leukemia and myelodysplastic syndrome. Bone marrow Wilms tumor gene 1 (WT1) expression was measured at time of transplant and post-transplant relapse. By using the Cox proportional hazards model, cut-off values for WT1 at both time points were obtained. The disease risk index incorporating initial cytogenetics and the disease stage at transplant as well as WT1 expression was significantly associated with overall survival, indicating that WT1 may represent a minimal residual disease marker in this context of cell therapy response evaluation, especially in high-risk patients currently considered to be in complete remission. Cut-off values for bone marrow WT1 expression for the two decisive treatment time points were proposed. Introduction: Post-transplant relapse of acute myeloid leukemia and myelodysplastic syndrome faces restricted effective salvage regimens. We retrospectively analyzed the use of Azacitidine–donor lymphocyte infusion (AZA/DLI) in this setting. Furthermore, data on bone marrow Wilms tumor gene 1 (WT1) expression were collected. Methods: A Cox proportional hazards model, an outcome-oriented approach for the lowest smoothed plot of the martingale residuals, was performed for the cut-point determination of the respective WT1 expression levels. Finally, a Cox proportional hazards model investigated the association of overall survival (OS) with predictors. Results: An overall response of 41.4% with a median duration of 11.9 months for stable disease and 19.5 months for complete response (CR) patients was achieved. The disease risk index (DRI) high-/very high-risk patients had a shorter OS of 4.4 months than intermediate-risk patients, with 14.5 months, p = 0.007. At transplant, WT1-overexpressing patients (>150 copies) had a shorter median OS of 5.3 months than low-WT1-expressing ones, with 13.5 months, p = 0.024. Furthermore, patients with ≤1000 WT1 copies at relapse had a significantly longer OS with 15.3 months than patients overexpressing WT1, with 4.4 months, p = 0.0002. Conclusions: DRI and WT1 expression associate significantly with OS after AZA/DLI. Hence, WT1 may represent an MRD marker, especially in CR patients at high risk. [ABSTRACT FROM AUTHOR]

The meiosis-specific kinase Mek1 regulates key steps in meiotic recombination in the budding yeast, Saccharomyces cerevisiae. MEK1 limits resection at double-strand break (DSB) ends and is required for preferential strand invasion into homologs, a process known as interhomolog bias. After strand invasion, MEK1 promotes phosphorylation of the synaptonemal complex protein Zip1 that is necessary for DSB repair mediated by a crossover-specific pathway that enables chromosome synapsis. In addition, Mek1 phosphorylation of the meiosis-specific transcription factor, Ndt80 , regulates the meiotic recombination checkpoint that prevents exit from pachytene when DSBs are present. Mek1 interacts with Ndt80 through a 5-amino acid sequence, RPSKR, located between the DNA-binding and activation domains of Ndt80. AlphaFold Multimer modeling of a fragment of Ndt80 containing the RPSKR motif and full-length Mek1 indicated that RPSKR binds to an acidic loop located in the Mek1 FHA domain, a noncanonical interaction with this motif. A second protein, the 5′-3′ helicase Rrm3 , similarly interacts with Mek1 through an RPAKR motif and is an in vitro substrate of Mek1. Genetic analysis using various mutants in the MEK1 acidic loop validated the AlphaFold model, in that they specifically disrupt 2-hybrid interactions with Ndt80 and Rrm3. Phenotypic analyses further showed that the acidic loop mutants are defective in the meiotic recombination checkpoint and, in certain circumstances, exhibit more severe phenotypes compared to the NDT80 mutant with the RPSKR sequence deleted, suggesting that additional, as yet unknown, substrates of Mek1 also bind to Mek1 using an RPXKR motif. [ABSTRACT FROM AUTHOR]

Background Allogeneic hematopoietic stem cell transplant for myeloid neoplasms with increased fibrosis is uncommon; morphologic features posttransplant can be concerning for persistent disease. Methods In this retrospective study, we identified 22 patients transplanted for myeloproliferative neoplasms or chronic myelomonocytic leukemia with fibrosis at our institution, and reviewed slides from pretransplant and posttransplant bone marrow biopsies. Clinical features and results of molecular, chimerism, and cytogenetic studies were retrieved from the medical record. Results Pretransplant bone marrow biopsies commonly exhibited hypercellularity, atypical megakaryocytes, and reticulin fibrosis. At day 100, 36% of biopsies had reticulin grade >MF1 and 33% of those tested had positive molecular studies, with no significant associations between day 100 marrow characteristics and molecular profile or peripheral count recovery times. In the 1 year posttransplant biopsies (n = 12), 7 of 9 had negative molecular studies; of these, none had reticulin grade >MF1, 1 had trichrome 1+, 2 had atypical megakaryocytes, and 1 was hypercellular. Conclusions Supporting recent literature, our study indicates that persistent day 100 reticulin fibrosis/collagen deposition does not show an association with day 100 molecular status. Our study additionally provides data for 12 patients with 1 year posttransplant marrow biopsies, with the majority of those lacking either increased fibrosis or molecular evidence of persistent disease. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: Maize is one of the most consumed grains worldwide. Its production and international trade are expected to continue increasing because of its use as animal fodder and direct human food. Although maize's history spans millennia, in the last century it underwent significant changes due to genetic engineering, particularly during the Green Revolution. Due to maize's importance for current food security and energy production, it is fundamental to understand this engineering process to assess the implications of current styles of maize production for local and global landscapes, scientific institutions, and transnational networks of agricultural science. Summary: This article aims to explain how Mexican agricultural expertise contributed to the development of cytogenetics as a specialized field in the study of the diversity of maize within the framework of the Green Revolution. To this end, the article follows the work of Mexican agronomist Takeo Ángel Kato Yamakake within the activities of the Inter‐American Maize Improvement Program (IMIP), formally established in 1960. By reconstructing the debate on the genetic implications of chromosomal structure and function, this study contributes to the historiography devoted to the role played by local experts in the classification, experimentation, and conservation of maize.The article is based on sources from Mexico and the United States, an interview with Kato, and the consultation of the database "Rockefeller Fellows. Individual Mobility Awards at Rockefeller‐endowed Organizations, 1914‐1970."Kato's trajectory provides an overview of agronomy in Mexico and shows the relevance of transnational exchange in the establishment of plant cytogenetics. Kato's academic activity features collaborations with key figures such as Edwin Wellhausen, Albert Longley, Barbara McClintock, W. Gallinat, Czeslawa Prywer, and Almiro Blumenschein.A Green Revolution era quest to unravel the origin of maize as a way of perfecting its genetic manipulation fueled the interest in establishing cytogenetics in Mexico. However, the irruption of the molecular approach made the study of the position of chromosomal knobs less of a priority. Despite this, classical cytogenetics, under Kato's leadership, remains a field that contributed to the knowledge of the vegetal genome, even when the IMIP disappeared and the logic of the Green Revolution lost its centrality. [ABSTRACT FROM AUTHOR]

The tribe Alticini (Newman, 1834) is a diverse and amply distributed group of beetles, although its internal arrangement is still poorly defined. The taxonomy of the subtribe Oedionychina is especially challenging, due to mimicry. The present study integrates cytogenetic, morphological, and molecular data to describe Alagoasa neoequestris sp. nov. and establishes its phylogenetic position within the group. The morphological characteristics of the new species are consistent with the genus Alagoasa. The comparison of the male genitalia among the species indicates reproductive isolation. The diploid number and the giant and asynaptic sex chromosomes are typical of the oedionychines, although with considerable differentiation in chromosome morphology and the distribution of the heterochromatin. The location of the rDNA 45S and 5S cistrons is conserved as in Coleoptera. The phylogenetic analysis placed A. neoequestris sp. nov. in Alagoasa , in a cluster with Alagoasa plaumanni , clearly separated from all other genera. The karyotype of the new species contradicts that reported for " Alagoasa equestris " (2n = 12), which coincides with that of the morphologically very similar Omophoita communis. It thus seems likely that " A. equestris " is in fact O. communis. The sum of the evidence supports clearly the description of the new Alagoasa species from southern Brazil. [ABSTRACT FROM AUTHOR]

Introduction: Limited data exist on interphase fluorescent in situ hybridization (iFISH)-based survival outcomes in newly diagnosed multiple myeloma (NDMM) from India. Objectives: To study the demographics and iFISH-based survival outcomes in NDMM patients treated with proteasome inhibitors from a community-based cancer setup. Materials and Methods: We reviewed the records of 25 patients treated with proteasome inhibitors between June 2017 and April 2023 using five high-risk (HR) iFISH markers based on mSMART 3.0. Results: The median age was 60 years (range 34–87). HR iFISH was detected in 12 (48%) patients. With a median follow-up of 27 months, the overall response at the last follow-up was 80% (very good partial response - 52%, complete remission - 20%, and partial response - 8%), with 8 (32%) relapses. Twenty (80%) patients remain alive, with five deaths in HR (sepsis [ n = 3]). The 2.5-year overall survival in HR and standard risk was 55.6% ± 15.2% and 100% (P = 0.01), and event-free survival was 32.4% ± 16.5% and 77.8% ± 13.8% (P = 0.02), respectively. Conclusions: Using limited iFISH HR markers helps in the early and effective stratification of NDMM in the real world. Sepsis remains an important cause of mortality in an Indian setup. [ABSTRACT FROM AUTHOR]

Main conclusion: This article explores possible future initiatives, such as the development of targeted breeding and integrated omics approach to boost little millet production, nutritional value, and environmental adaptation. Little millet (P. sumatrense) is a staple grain in many parts of Asia and Africa owing to its abundance in vitamins and minerals and its ability to withstand harsh agro-ecological conditions. Enhancing little millet using natural resources and novel crop improvement strategy is an effective way of boosting nutritional and food security. To understand the genetic makeup of the crop and figure out important characteristics linked to nutritional value, biotic and abiotic resistance, and production, researchers in this field are currently resorting on genomic technology. These realizations have expedited the crop's response to shifting environmental conditions by enabling the production of superior cultivars through targeted breeding. Going forward, further improvements in breeding techniques and genetics may boost the resilience, nutritional content, and production of little millet, which would benefit growers and consumers alike. The research and development on little millet improvement using novel omics platform and the integration of genetic resources are summarized in this review paper. Improved cultivars of little millet that satisfy changing farmer and consumer demands have already been developed through the use of these novel breeding strategies. This article also explores possible future initiatives, such as the development of targeted breeding, genomics, and sustainable agriculture methods. The potential for these measures to boost little millet's overall production, nutritional value, and climate adaptation will be extremely helpful in addressing nutritional security. Integrated omics for little millet improvement [ABSTRACT FROM AUTHOR]

Two new diagnostic classifications of acute myeloid leukemia (AML) were published in 2022 to update current knowledge on disease biology. In previous 2017-edition categories of AML with myelodysplasia-related changes, AML was not otherwise specified, but AML with mutated RUNX1 experienced profound changes. We performed whole exome sequencing on a cohort of 69 patients with cytogenetic intermediate-risk AML that belonged to these diagnostic categories to correlate their mutational pattern and copy-number alterations with their new diagnostic distribution. Our results show that 45% of patients changed their diagnostic category, being AML myelodysplasia-related the most enlarged, mainly due to a high frequency of myelodysplasia-related mutations (58% of patients). These showed a good correlation with multilineage dysplasia and/or myelodysplastic syndrome history, but at the same time, 21% of de novo patients without dysplasia also presented them. RUNX1 was the most frequently mutated gene, with a high co-occurrence rate with other myelodysplasia-related mutations. We found a high prevalence of copy-neutral loss of heterozygosity, frequently inducing a homozygous state in particular mutated genes. Mild differences in current classifications explain the diagnostic disparity in 10% of patients, claiming a forthcoming unified classification. [ABSTRACT FROM AUTHOR]

Background: BCR::ABL1-like or Philadelphia chromosome-like (Ph-like) acute lymphoblastic leukemia (ALL) was first reported in 2009. Ph-like ALL is characterized by gene signature similar to Philadelphia chromosome ALL, but without BCR::ABL1 fusions. Molecularly, Ph-like ALL is divided into seven categories, with CRLF2 and ABL-class rearrangements being the two most common subtypes, exhibiting alterations in distinct downstream signaling cascades. Case presentation: We report a rare case of pediatric Ph-like ALL with concomitant CRLF2 and ABL1 rearrangements. CRLF2 was fused with P2RY8, its most common fusion partner, whereas ABL1 was fused with MYO18B, a novel fusion partner that has not been previously reported. The 4-year-old female patient was treated using the national multicenter CCCG-ALL-2020 protocol with the addition of dasatinib at the end of induction when ABL1 rearrangement was confirmed by RNA-seq. Morphologically and molecularly, the patient remained in continuous remission until the last follow-up. To the best of our knowledge, this is the first case of Ph-like ALL harboring two distinct rearrangement categories. Conclusions: Our results identified that ABL1 rearrangement and CRLF2 rearrangement can coexist. The application of FISH, whole transcription sequencing, PCR can help us to have a more comprehensive understanding of ALL cytogenetics and molecular biology. Further studies are needed to explore the role of targeted therapies in such rare clinical scenarios. [ABSTRACT FROM AUTHOR]

Utilization of crop wild relatives of wheat can be very effective in building the genetic diversity to cater to the evolving strains of disease pathogens. Aegilops speltoides is a rich source of rust resistance genes however transferring those to wheat genome can be tedious due to co-transfer and preferential transmission of undesirable genes causing gametocidal activity. Such an unholy association was observed in Triticum aestivum-Ae. speltoides derivative line Sel. 2427 which possess the broad-spectrum leaf rust seedling resistance gene (LrS2427). Molecular analysis based on 35 K wheat breeder's array revealed the maximum percentage of Ae. speltoides genome introgression on homoeologous group 2. In situ hybridization studies revealed the presence of S genome in Sel. 2427, showing six translocations on four chromosomes. Karyotyping using repetitive probe (AAG)6 revealed that the two chromosomes involved are 2D and 2B. Genic regions causing gametocidal activity were identified by dissecting it into component traits and QTLs on 2D and 2B chromosomes were revealed in case of the trait seed shrivelling index. To break the inadvertent association of LrS2427 with gametocidal genes, F1(Agra Local X Sel. 2427) seeds were irradiated with gamma rays and stable leaf rust resistant mutants lacking gametocidal activity were developed. These mutants showed resistance to different races of leaf rust pathogen and showed superior agronomic performance as well. These mutants could be a great resource in wheat improvement for utilization of the leaf rust resistance gene LrS2427 without any yield penalty. [ABSTRACT FROM AUTHOR]

Simple Summary: Juvenile Myelomonocytic Leukemia (JMML) is a rare and clonal hematopoietic disorder of infancy and early childhood with myeloproliferative/myelodysplastic features resulting from germline or somatic mutations in the RAS pathway. Given its rarity, management is not standardized and varies widely, ranging from observation to bone marrow transplant depending on genomic and clinical features. We describe the course of JMML or Noonan Syndrome-associated Myeloproliferative Disorder in 22 pediatric patients treated at three institutions to provide guidance for monitoring versus intervention, including transplant, supported by patient outcomes. We provide additional insight into the expected time to spontaneous resolution in those with germline PTPN11 mutations and treatment approaches for patients with germline CBL mutations where no standard exists. Juvenile Myelomonocytic Leukemia (JMML) is a rare and clonal hematopoietic disorder of infancy and early childhood with myeloproliferative/myelodysplastic features resulting from germline or somatic mutations in the RAS pathway. Treatment is not uniform, with management varying from observation to stem cell transplant. The aim of our retrospective review is to describe the treatment and outcomes of a cohort of patients with JMML or Noonan Syndrome-associated Myeloproliferative Disorder (NS-MPD) to provide management guidance for this rare and heterogeneous disease. We report on 22 patients with JMML or NS-MPD managed at three institutions in the Texas Medical Center. Of patients with known genetic mutations and cytogenetics, 6 harbored germline mutations, 12 had somatic mutations, and 9 showed cytogenetic abnormalities. Overall, 14/22 patients are alive. Spontaneous clinical remission occurred in one patient with somatic NRAS mutation, as well as two with germline PTPN11 mutations with NS-MPD, and two others with germline PTPN11 mutations and NS-MPD remain under surveillance. Patients with NS-MPD were excluded from treatment analysis as none required chemotherapeutic intervention. All patients (5/5) treated with 5-azacitidine alone and one of the four treated with 6-mercaptopurine monotherapy had a reduction in mutant variant allele frequency. Transformation to acute myeloid leukemia was seen in two patients who both died. Among patients who received transplants, 7/13 are alive, and relapse post-transplant occurred in 3/13 with a median time to relapse of 3.55 months. This report provides insight into therapy responses and long-term outcomes across different genetic subsets of JMML and lends insight into the expected time to spontaneous resolution in patients with NS-MPD with germline PTPN11 mutations. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRs) play a crucial role in the leukemogenesis and the prognosis of acute myeloid leukemia (AML). This study investigated the therapeutic effects of resveratrol, gallic acid, and piperine as natural anticancer agents on the HL-60 cell line and their roles in apoptosis. In this experimental study, quantitative analysis of miRs, including miR-17, miR-92b, miR-181a, and miR-222, were performed in 150 newly diagnosed patients with AML by real-time PCR assay. HL-60 cell viability as well as the expression of miRs, BAX, BCL-2, MCL-1, WT1, c-Kit, and CEBPA, were also assessed after transfection with the LNA-miRs and treatment with resveratrol, gallic acid, and piperine. The expression of miR-17 and miR-181a decreased significantly in LNA-anti-miRs. Although HL-60 cell viability decreased in LNA-anti-miR-222, miR-17, and miR-92b, blockade of miR-181a increased the cell viability. Besides, the cell viability increased merely in the piperine-treated group. Compared to untreated cells, miR-17 and miR-92b expression significantly increased in gallic acid- and resveratrol-treated cells. In HL-60 cells treated with resveratrol, gallic acid, and piperine, the expression of miR-181a was also increased significantly. The expression of BAX was also increased in resveratrol and piperine-treated groups. Compared to untreated cells, the expression of c-Kit increased significantly in the piperine-treated group; however, it decreased in the resveratrol-treated group. LNA-anti-miRs may be a promising agent for the treatment of AML. All three compounds used in this study showed anticancer effects, which can exert the desired outcome in patients with AML. [ABSTRACT FROM AUTHOR]

The prognostic and predictive role of specific gene mutations in Waldenström Macroglobulinemia (WM) is well-ascertained whereas the clinical impact of chromosome aberrations is far less known. Recent work has provided initial evidence for an adverse prognostic impact of some aberrations, such as del(6q), while other studies suggest a possible relationship between some clinical features (e.g. advanced age and/or inflammatory status) and specific cytogenetic abnormalities. To add to the still limited knowledge on WM cytogenetics and its clinical implications, we herein report our experience in a cohort of WM patients across 23 years. Based on our retrospective study, we found that abnormal karyotype was more represented in older patients and maintained a statistically significant independence from other molecular, clinical, and biological features related to WM. The presence and number of cytogenetic aberrations correlated with inferior overall and progression-free survival outcomes regardless of the type of single chromosome aberration. Our data suggests that the role of the altered karyotype deserves to be further clarified especially in elderly WM patients, in whom cytogenetic abnormalities and disease biology appear to be characterized by a higher degree of complexity. [ABSTRACT FROM AUTHOR]

Chronic myeloid leukemia (CML) is a neoplastic disease of genetic origin resulting from clonal proliferation of hematopoietic stem cells (HSCs). The reciprocal translocation t(9;22)(q34;q11) is the main chromosomal abnormality involved in this pathology, usually detected by conventional cytogenetics. This article aims to investigate the epidemiological, cytogenetic, therapeutic, and clinical characteristics of Moroccan patients with CML. This research represents the first large-scale study of CML patients in Morocco and was carried out at Institut Pasteur of Morocco. Bone marrow samples were processed for cytogenetic analysis, and karyotypes were described according to an international system of human cytogenetic nomenclature (ISCN 2016). Patients were studied according to their epidemiological characteristics, clinical information and cytogenetic results. For statistical calculations, R version 4.3.1 was used to analyze the data and calculate the statistical parameters. RStudio and Power BI were used for data visualization. The National Cancer Institute (NCI) Surveillance, Epidemiology, and End Results (SEER) method of incidence estimation was used to calculate our incidence. We received 826 patients (from 1992 to 2023) who were referred for suspected CML or who were undergoing treatment. Only 650 patients with confirmed CML were included in the study, all of whom underwent their first cytogenetic test. The median age of our patients was 45 years and the sex ratio was 1.03. At the time of diagnosis, 147 (30%) of the patients had clinical manifestations. Most patients were diagnosed in the chronic phase (94.5%). Nineteen complex variant translocations of the Philadelphia (Ph) chromosome were detected. At the time of diagnosis, 55 (11.5%) patients had ACAs, of which 30 (54.5%) were high-risk ACAs. Based on data from 174 patients treated with imatinib, the median time to complete cytogenetic response (CCyR) was 11 months, and at the last cytogenetic follow-up, 81 patients (46.6%) achieved CCyR, while 64 patients (36.8%) showed no response to treatment. Regarding adherence to European LeukemiaNet (ELN) guidelines, 58 patients (33%) were followed according to these guidelines, with optimal treatment in 8.6%, suboptimal treatment in 7% and treatment failure in 18%. The estimated incidence of chronic myeloid leukemia calculated is 0.6 cases per 100,000 in the Casablanca region. This study provides a detailed overview of CML in Morocco, highlighting important clinical, cytogenetic and therapeutic aspects despite some limitations. It also highlights the need to deepen our understanding of this complex disease for disease management in our specific context. [ABSTRACT FROM AUTHOR]

Context.--: Conventional karyotype analysis, which provides comprehensive cytogenetic information, plays a significant role in the diagnosis and risk stratification of hematologic neoplasms. The main limitations of this approach include long turnaround time and laboriousness. Therefore, we developed an integral R-banded karyotype analysis system for bone marrow metaphases, based on deep learning. Objective.--: To evaluate the performance of the internal models and the entire karyotype analysis system for R-banded bone marrow metaphase. Design.--: A total of 4442 sets of R-banded normal bone marrow metaphases and karyograms were collected. Accordingly, 4 deep learning-based models for different analytic stages of karyotyping, including denoising, segmentation, classification, and polarity recognition, were developed and integrated as an R-banded bone marrow karyotype analysis system. Five-fold cross validation was performed on each model. The whole system was implemented by 2 strategies of automatic and semiautomatic workflows. A test set of 885 metaphases was used to assess the entire system. Results.--: The denoising model achieved an intersection-over-union (IoU) of 99.20% and a Dice similarity coefficient (DSC) of 99.58% for metaphase acquisition. The segmentation model achieved an IoU of 91.95% and a DSC of 95.79% for chromosome segmentation. The accuracies of the segmentation, classification, and polarity recognition models were 96.77%, 98.77%, and 99.93%, respectively. The whole system achieved an accuracy of 93.33% with the automatic strategy and an accuracy of 99.06% with the semiautomatic strategy. Conclusions.--: The performance of both the internal models and the entire system is desirable. This deep learning-based karyotype analysis system has potential in a clinical application. [ABSTRACT FROM AUTHOR]

Autopolyploidy is taxonomically defined as the presence of more than two copies of each genome within an organism or species, where the genomes present must all originate within the same species. Alternatively, "genetic" or "cytological" autopolyploidy is defined by polysomic inheritance: random pairing and segregation of the four (or more) homologous chromosomes present, with no preferential pairing partners. In this review, we provide an overview of methods used to categorize species as taxonomic and cytological autopolyploids, including both modern and obsolete cytological methods, marker‐segregation‐based and genomics methods. Subsequently, we also investigated how frequently polysomic inheritance has been reliably documented in autopolyploids. Pure or predominantly polysomic inheritance was documented in 39 of 43 putative autopolyploid species where inheritance data was available (91%) and in seven of eight synthetic autopolyploids, with several cases of more mixed inheritance within species. We found no clear cases of autopolyploids with disomic inheritance, which was likely a function of our search methodology. Interestingly, we found seven species with purely polysomic inheritance and another five species with partial or predominant polysomic inheritance that appear to be taxonomic allopolyploids. Our results suggest that observations of polysomic inheritance can lead to relabeling of taxonomically allopolyploid species as autopolyploid and highlight the need for further cytogenetic and genomic investigation into polyploid origins and inheritance types. [ABSTRACT FROM AUTHOR]

PURPOSE: AML is a hematologic cancer that is clinically heterogeneous, with a wide range of clinical outcomes. DNA methylation changes are a hallmark of AML but are not routinely used as a criterion for risk stratification. The aim of this study was to explore DNA methylation markers that could risk stratify patients with cytogenetically normal AML (CN-AML), currently classified as intermediate-risk. MATERIALS AND METHODS: DNA methylation profiles in whole blood samples from 77 patients with CN-AML in The Cancer Genome Atlas (LAML cohort) were analyzed. Individual 5'-cytosine-phosphate-guanine-3' (CpG) sites were assessed for their ability to predict overall survival. The output was validated using DNA methylation profiles from bone marrow samples of 79 patients with CN-AML in a separate data set from the Gene Expression Omnibus. RESULTS: In the training set, using DNA methylation data derived from the 450K array, we identified 2,549 CpG sites that could potentially distinguish patients with CN-AML with an adverse prognosis (intermediate-poor) from those with a more favorable prognosis (intermediate-favorable) independent of age. Of these, 25 CpGs showed consistent prognostic potential across both the 450K and 27K array platforms. In a separate validation data set, nine of these 25 CpGs exhibited statistically significant differences in 2-year survival. These nine validated CpGs formed the basis for a combined prognostic biomarker panel, which includes an 8-CpG Somatic Panel and the methylation status of cg23947872. This panel displayed strong predictive ability for 2-year survival, 2-year progression-free survival, and complete remission in the validation cohort. CONCLUSION: This study highlights DNA methylation profiling as a promising approach to enhance risk stratification in patients with CN-AML, potentially offering a pathway to more personalized treatment strategies. Our study identified 9 DNA methylation markers as potential prognostic biomarkers that effectively differentiate cytogenetically normal AML patients with an adverse prognosis from those with a more favorable prognosis, regardless of age. The identified 9 CpGs form a robust biomarker panel that accurately predicts 2-year survival, 2-year progression-free survival, and complete remission, highlighting the potential of DNA methylation in improving CN-AML risk assessment and personalized treatment. [ABSTRACT FROM AUTHOR]

Three classes of BCMA-directed therapy (BDT) exist: antibody drug-conjugates (ADCs), CAR-T, and T-cell engagers (TCEs), each with distinct strengths and weaknesses. To aid clinicians in selecting between BDTs, we reviewed myeloma patients treated at Mayo Clinic with commercial or investigational BDT between 2018-2023. We identified 339 individuals (1-exposure = 297, 2-exposures = 38, 3-exposures = 4) who received 385 BDTs (ADC = 59, TCE = 134, CAR-T = 192), with median follow-up of 21-months. ADC recipients were older, with more lines of therapy (LOT), and penta-refractory disease. Compared to ADCs, CAR-T (aHR = 0.29, 95%CI = 0.20–0.43) and TCEs (aHR = 0.62, 95%CI = 0.43–0.91) had better progression-free survival (PFS) on analysis adjusted for age, the presence of extramedullary (EMD), penta-refractory disease, multi-hit high-risk cytogenetics, prior BDT, and the number of LOT in the preceding 1-year. Likewise, compared to ADCs, CAR-T (aHR = 0.28, 95%CI = 0.18–0.44) and TCEs (aHR = 0.60, 95%CI = 0.39–0.93) had superior overall survival. Prior BDT exposure negatively impacted all classes but was most striking in CAR-T, ORR 86% vs. 50% and median PFS 13-months vs. 3-months. Of relapses, 54% were extramedullary in nature, and a quarter of these cases had no history of EMD. CAR-T demonstrates superior efficacy and where feasible, should be the initial BDT. However, for patients with prior BDT or rapidly progressive disease, an alternative approach may be preferable. [ABSTRACT FROM AUTHOR]

Endothelial cells (ECs) maintain vessel tone and barrier integrity, regulate blood homeostasis, and prevent the extravasation of leukocytes under normal physiological conditions. Because of the limited lifespans and batch-to-batch differences with respect to the genetic make-up of primary ECs, established immortal EC lines are extensively used for studying endothelial biology. To address this issue, the immortal endothelial cell line EA.hy926 was developed by fusing primary human umbilical vein endothelial cells (HUVECs) with human lung carcinoma A549 cells. EA.hy926 cells share a number of similar endothelial properties with HUVECs and are considered the immortal counterpart to primary HUVECs. However, the cytogenetic integrity of EA.hy926 cells is not fully elucidated. We characterized EA.hy926 cells with conventional G-banding and molecular cytogenetic techniques such as spectral karyotyping and subtelomeric fluorescence in situ hybridization. Cytogenetic analysis revealed an array of numerical and stable structural chromosomal rearrangements including one deletion, one duplication, one isochromosome, seven simple translocations, and five complex translocations in Ea.hy926 cells. These findings will advance comprehension of EA.hy926 cell biology and augment future endothelial studies, specifically in comparison studies between HUVECs and EA.hy926 cells. [ABSTRACT FROM AUTHOR]

Among the repetitive elements, satellite DNA (SatDNA) emerges as extensive arrays of highly similar tandemly repeated units, spanning megabases in length. Given that the satDNA PboSat01-176, previously characterized in P. boiei, prompted our interest for having a high abundance in P. boiei and potential for centromeric satellite, here, we employed various approaches, including low coverage genome sequencing, followed by computational analysis and chromosomal localization techniques in four Proceratophrys species and, investigating the genomic presence and sharing, as well as its potential for chromosomal centromere marker in Proceratophrys frog species. Our findings demonstrate that PboSat01-176 exhibits high abundance across all four Proceratophrys species, displaying distinct characteristics that establish it as the predominant repetitive DNA element in these species. The satellite DNA is prominently clustered in the peri/centromeric region of the chromosomes, particularly in the heterochromatic regions. The widespread presence of PboSat01-176 in closely related Proceratophrys species reinforces the validity of the library hypothesis for repetitive sequences. Thus, this study highlighted the utility of the satDNA family PboSat01-176 as a reliable centromeric marker in Proceratophrys species, with potential to be applied in other species of anuran amphibians. The observed sharing and maintenance of this sequence within the genus suggest possibilities for future research, particularly through expanded sampling to elucidate parameters that underlie the library hypothesis and the evolutionary dynamics of satDNA sequences. [ABSTRACT FROM AUTHOR]

The genome organization of woodpeckers has several distinctive features e.g., an uncommon accumulation of repetitive sequences, enlarged Z chromosomes, and atypical diploid numbers. Despite the large diversity of species, there is a paucity of detailed cytogenomic studies for this group and we thus aimed to rectify this. Genome organization patterns and hence evolutionary change in the microchromosome formation of four species (Colaptes campestris, Veniliornis spilogaster, Melanerpes candidus, and Picumnus nebulosus) was established through fluorescence in situ hybridization using bacterial artificial chromosomes originally derived from Gallus gallus and Taeniopygia guttata. Findings suggest that P. nebulosus (2n = 110), which was described for the first time, had the most basal karyotype among species of Picidae studied here, and probably arose as a result of fissions of avian ancestral macrochromosomes. We defined a new chromosomal number for V. spilogaster (2n = 88) and demonstrated microchromosomal rearrangements involving C. campestris plus a single, unique hitherto undescribed rearrangement in V. spilogaster. This comprised an inversion after a fusion involving the ancestral microchromosome 12 (homologous to chicken microchromosome 12). We also determined that the low diploid number of M. candidus is related to microchromosome fusions. Woodpeckers thus exhibit significantly rearranged karyotypes compared to the putative ancestral karyotype. [ABSTRACT FROM AUTHOR]

Objective: DNA methylation data can be used to derive mitotic indices from complex tissues. Here, we assessed if the DNA methylation‐derived mitotic ageing indices are associated with oral squamous cell carcinoma (OSCC) development and recurrence‐free survival (RFS). Methods: DNA methylation‐based mitotic indices (MitoticAge, TNSC and hypoSC) were derived using algorithms "MitoticAge" and "epiTOC2" for the discovery [non‐malignant (n = 22), premalignant (n = 22) and OSCC (n = 68) tissues] and validation datasets (GSE87053, GSE136704 and TCGA‐HNSCC). Differences in mitotic indices between non‐malignant, premalignant and OSCC tissues were assessed. Finally, the association between estimated mitotic indices and RFS was evaluated in OSCCs. Results: In the discovery and validation datasets, increased mitotic ageing was observed in OSCC compared to non‐malignant and premalignant oral tissues. HPV‐positive HNSCCs had higher mitotic index TNSC. Mitotic age index hypoSC was associated with RFS in OSCC (p = 0.011, HR 2.61, 95% CI 1.24–5.48). Conclusions: DNA methylation‐derived mitotic indices are associated with OSCC development and RFS. Thus, DNA methylation‐derived mitotic indices may be a valuable research tool to reliably estimate the cumulative number of stem cell divisions in malignant and non‐malignant oral tissues. Future research utilizing mitotic indices for predicting clinical outcomes in OSCC is warranted. [ABSTRACT FROM AUTHOR]

This interlaboratory comparison was conducted to evaluate the performance of the Latin-American Biodosimetry Network (LBDNet) in analyzing digitized images for scoring dicentric chromosomes from in vitro irradiated blood samples. The exercise also assessed the use of weighted robust algorithms to compensate the uneven expertise among the participating laboratories. Three sets of coded images obtained through the dicentric chromosome assay from blood samples irradiated at 1.5 Gy (sample A) and 4 Gy (sample B), as well as a non-irradiated whole blood sample (sample C), were shared among LBDNet laboratories. The images were captured using the Metafer4 platform coupled with the AutoCapt module. The laboratories were requested to perform triage scoring, conventional scoring, and dose estimation. The dose estimation was carried out using either their laboratory calibration curve or a common calibration curve. A comparative statistical analysis was conducted using a weighted robust Hampel algorithm and z score to compensate for uneven expertise in dicentric analysis and dose assessment among all laboratories. Out of twelve laboratories, one had unsatisfactory estimated doses at 0 Gy, and two had unsatisfactory estimated doses at 1.5 Gy when using their own calibration curve and triage scoring mode. However, all doses were satisfactory at 4 Gy. Six laboratories had estimated doses within 95% uncertainty limits at 0 Gy, seven at 1.5 Gy, and four at 4 Gy. While the mean dose for sample C was significantly biased using robust algorithms, applying weights to compensate for the laboratory's analysis expertise reduced the bias by half. The bias from delivered doses was only notable for sample C. Using the common calibration curve for dose estimation reduced the standard deviation (s*) estimated by robust methods for all three samples. The results underscore the significance of performing interlaboratory comparison exercises that involve digitized and electronically transmitted images, even when analyzing non-irradiated samples. In situations where the participating laboratories possess different levels of proficiency, it may prove essential to employ weighted robust algorithms to achieve precise outcomes. [ABSTRACT FROM AUTHOR]

European wild carnations (Dianthus) are represented by a high number of taxa organized in unresolved taxonomies. In particular, taxa belonging to the Dianthus virgineus L. complex in the Central Mediterranean have been delimited mainly with qualitative morphological data and still await quantitative investigations, which are vital to understand boundaries and relations among plant diversity groups. Here, we examine the phenotypic features of nuclear genome organization testing for species boundaries in this complex. We have studied the chromosome number, the total haploid length (THL), and the relative genome size (RGS) in 122 populations belonging to 25 out of 33 taxa of the complex. All the studied populations have 2n = 2x = 30 chromosomes, and the THL ranges from 14.09 to 20.71 μm. Genome size estimations support the absence of polyploidization events, but show a certain degree of variation (0.318–0.423 arbitrary units). The RGS variation is not in agreement with current taxonomic treatment, but rather shows a geographical pattern, with higher values in Sicily and Sardinia. No correlation between the THL and the RGS was detected, possibly due to the stable chromosome number and the small size of chromosomes. A number of evolutionary unique groups lower than the number of currently accepted taxa may be hypothesized. [ABSTRACT FROM AUTHOR]

The most prevalent form of dementia, Alzheimer's disease (AD) is a chronic illness that is on the rise among the geriatric population. Even though research into its biochemical, genetic, and cytogenetic pathways has advanced, its aetiology is still unclear and complex. In this study, we recruited sixty-eight participants diagnosed with AD where the cytogenetic, biochemical parameters and genetic mutations were analysed. Our results revealed chromosomal aberrations such as aneuploidies in the peripheral blood of Alzheimer's disease patients. Biochemical parameters revealed no statistical significance in the study though a pattern could be observed in the serum levels. Further few novel mutations at the c.21 C > T, c.56G > A were observed in the MCU gene of mitochondrial calcium uniporter. All these findings reveal the need for a larger cohort study to gain a better and more detailed understanding of the aetiology of Alzheimer's disease. [ABSTRACT FROM AUTHOR]

Cytogenetic studies were carried out on 11 species of Indian Snakes collected from Jammu region using Air Drying Technique of Gorman et al 1979. Among all E. johni and E. conicus belonging to primitive family Boidae exhibits diploid number, 2n=34 with undifferentiated sex chromosomes in both male and female. In family Colubridae (an intermediate family) there exist huge variation as far as sex chromosomes are concerned i.e Ptyas mucosus has 2n=34, Oligodon arnensis has 2n=44 with undifferentiated sex chromosomes, Lycodon arnensis and Boiga trigonata both have 2n=36 with differentiated sex chromosomes(as per literature) while Natrix stolata has 2n=36 with distinct 'ZW' female. In Family Elapidae Naja naja naja has 2n=38 with undifferentiated sex chromosomes but Bungarus caerulus has 2n=44 with 'ZW' female having submetacentric 'Z' and largest telocentric 'W' but members of family Viperidae viz. Vipera russelli and Echinis carinatus both have 2n=36 with well differentiated 'ZW' where 'W' is smaller and 'Z' larger representing final step in the evolution of sex chromosome. [ABSTRACT FROM AUTHOR]

Simple Summary: Current recommendations suggest setting two parallel cytogenetic cultures with 12-O-tetradecanoly-phorpol-13-acetate (TPA) and IL2+DSP30 as a mitogen to detect complex karyotypes (CKs) in chronic lymphocytic leukemia (CLL). However, studies comparing CK detection concordance between both methods in the same cohort are lacking. Herein, we evaluated the performance of two parallel cultures in a CLL cohort of 255 patients, specifically comparing CK detection (globally and in each individual patient). The CK detection rates and their prognostic impacts were similar for both mitogens. However, nearly one-third of CKs were only identified in one culture, mainly due to the detection of a normal karyotype or no metaphases in the other. In summary, the assessment of parallel cytogenetic cultures is the best strategy to detect CKs in CLL. Nonetheless, as IL2+DSP30 achieved the best performance, it should be prioritized above TPA if a single analysis is required to optimize cytogenetic assessment in routine practice. Current CLL guidelines recommend a two parallel cultures assessment using TPA and IL2+DSP30 mitogens for complex karyotype (CK) detection. Studies comparing both mitogens for CK identification in the same cohort are lacking. We analyzed the global performance, CK detection, and concordance in the complexity assessment of two cytogenetic cultures from 255 CLL patients. IL2+DSP30 identified more altered karyotypes than TPA (50 vs. 39%, p = 0.031). Moreover, in 71% of those abnormal by both, IL2+DSP30 identified more abnormalities and/or abnormal metaphases. CK detection was similar for TPA and IL2+DSP30 (10% vs. 11%). However, 11/33 CKs (33%) were discordant, mainly due to the detection of a normal karyotype or no metaphases in the other culture. Patients requiring treatment within 12 months after sampling (active CLL) displayed significantly more CKs than those showing a stable disease (55% vs. 12%, p < 0.001). Disease status did not impact cultures' concordance (κ index: 0.735 and 0.754 for stable and active). Although CK was associated with shorter time to first treatment (TTFT) using both methods, IL2+DSP30 displayed better accuracy than TPA for predicting TTFT (C-index: 0.605 vs. 0.580, respectively). In summary, the analysis of two parallel cultures is the best option to detect CKs in CLL. Nonetheless, IL2+DSP30 could be prioritized above TPA to optimize cytogenetic assessment in clinical practice. [ABSTRACT FROM AUTHOR]

Simple Summary: Neotropical electric fish have a large diversity in the Amazon region. We investigated the karyotype of the species Brachyhypopomus brevirostris from two localities in Brazil's northern region, Santarém in Pará state and Tefé in Amazonas state, using classical and molecular cytogenetics. Specimens from both localities presented the same karyotype. These are the first results regarding the distribution of repetitive sequences for B. brevirostris samples from the Tefé locality, and the first karyotypic description for the Santarém locality. These results differ from those previously described for samples from Humaitá (Amazon state). This karyotypic difference suggests that the Humaitá sample belongs to another species, which is reinforced in the recent redescription of the genus Brachyhypopomus. Brachyhypopomus (Hypopomidae, Gymnotiformes) is a monophyletic genus consisting of 28 formally described species. Karyotypic data are available for 12 species. The same karyotype is described for two species (B. brevirostris and B. hamiltoni), as well as different karyotypes for the same species from distinct locations (B. brevirostris). In this context, B. brevirostris may constitute a cryptic species complex. Thus, in the present study, we analyzed the karyotype of B. brevirostris, from Santarém, Pará, and Tefé, Amazonas, using classical cytogenetics (conventional staining and C-banding) and molecular techniques (fluorescence in situ hybridization using 18S rDNA, 5S rDNA, U2 snRNA, and telomeric probes). The results show that samples from both locations present 2n = 38, with all chromosomes being acrocentric (FC = 38a). In both populations, 18S rDNA sequences are present on only one pair of homologous chromosomes and telomeric sequences occur only at the ends of the chromosomes. In the Tefé sample, the 5S rDNA occurs in two pairs, and the U2 snRNA in three pairs. These results are the first descriptions of these sequences for B. brevirostris samples from the Tefé locality, as well as the first karyotypic description for the Santarém locality. Future cytotaxonomic studies of this genus can benefit from these results. [ABSTRACT FROM AUTHOR]

SUMMARY: The sugarcane (Saccharum spp.) genome is one of the most complex of all. Modern varieties are highly polyploid and aneuploid as a result of hybridization between Saccharum officinarum and S. spontaneum. Little research has been done on meiotic control in polyploid species, with the exception of the wheat Ph1 locus harboring the ZIP4 gene (TaZIP4‐B2) which promotes pairing between homologous chromosomes while suppressing crossover between homeologs. In sugarcane, despite its interspecific origin, bivalent association is favored, and multivalents, if any, are resolved at the end of prophase I. Thus, our aim herein was to investigate the purported genetic control of meiosis in the parental species and in sugarcane itself. We investigated the ZIP4 gene and immunolocalized meiotic proteins, namely synaptonemal complex proteins Zyp1 and Asy1. The sugarcane ZIP4 gene is located on chromosome 2 and expressed more abundantly in flowers, a similar profile to that found for TaZIP4‐B2. ZIP4 expression is higher in S. spontaneum a neoautopolyploid, with lower expression in S. officinarum, a stable octoploid species. The sugarcane Zip4 protein contains a TPR domain, essential for scaffolding. Its 3D structure was also predicted, and it was found to be very similar to that of TaZIP4‐B2, reflecting their functional relatedness. Immunolocalization of the Asy1 and Zyp1 proteins revealed that S. officinarum completes synapsis. However, in S. spontaneum and SP80‐3280 (a modern variety), no nuclei with complete synapsis were observed. Importantly, our results have implications for sugarcane cytogenetics, genetic mapping, and genomics. Significance Statement: Our work provides insights into the genetic control of meiosis in sugarcane (Saccharum spp.), a man made polyploid and fertile plant of interspecific constitution. Inspired by the discoveries of the Ph1 locus, which harbors the ZIP4 gene in wheat, we identified this meiotic gene in both parental species and in two current sugarcane varieties. We analyzed both gene and protein sequence conservation, protein domains, and predicted the 3D‐protein structure. We also investigated the level of ZIP4 expression in different sugarcane tissues. Like its role in wheat, ZIP4 seems to promote pairing between homologous chromosomes while suppressing crossover between homeologs in Saccharum. Using immunocytology, we were able to determine synaptonemal complex polymerization during prophase I, using Asy1 and Zyp1 sugarcane specific antibodies, revealing synapsis defects in all genotypes except Saccharum officinarum, a parental species with regular meiotic behavior. [ABSTRACT FROM AUTHOR]

Chromatin organization and its interactions are essential for biological processes, such as DNA repair, transcription, and DNA replication. Detailed cytogenetics data on chromatin conformation, and the arrangement and mutual positioning of chromosome territories in interphase nuclei are still widely missing in plants. In this study, level of chromatin condensation in interphase nuclei of rice (Oryza sativa) and the distribution of chromosome territories (CTs) were analyzed. Super-resolution, stimulated emission depletion (STED) microscopy showed different levels of chromatin condensation in leaf and root interphase nuclei. 3D immuno-FISH experiments with painting probes specific to chromosomes 9 and 2 were conducted to investigate their spatial distribution in root and leaf nuclei. Six different configurations of chromosome territories, including their complete association, weak association, and complete separation, were observed in root meristematic nuclei, and four configurations were observed in leaf nuclei. The volume of CTs and frequency of their association varied between the tissue types. The frequency of association of CTs specific to chromosome 9, containing NOR region, is also affected by the activity of the 45S rDNA locus. Our data suggested that the arrangement of chromosomes in the nucleus is connected with the position and the size of the nucleolus. [ABSTRACT FROM AUTHOR]

Although chromosomes of only 20 members of Pteromalidae sensu lato (s.l.), which belong to the families Pteromalidae sensu stricto (hence Pteromalidae) and Spalangiidae, are studied up to now, the accumulated cytogenetic information has important implications for taxonomic and evolutionary studies of these parasitoids. Within the former family, which includes the overwhelming majority of karyotypically studied species of Pteromalidae s.l., the known haploid chromosome number (n) can vary from 4 to 7 in Pachycrepoideus vindemmiae (Rondani) and Anisopteromalus calandrae (Howard), respectively, with a clear mode at n = 5. Among these parasitoids, Nasonia vitripennis (Walker) is the most thoroughly studied species in terms of modern cytogenetic techniques. On the contrary, chromosomes of only two members of Spalangiidae are known, both belonging to the Spalangia endius Walker complex, with n = 4 and 6. A few cosmopolitan cryptic species of the family Pteromalidae were studied using cytogenetic approaches. Specifically, Anisopteromalus quinarius Gokhman et Baur, a newly described parasitoid of stored‐product pests with n = 5, was initially separated from A. calandrae based on its different chromosome number. Another pteromalid with a similar biology, Lariophagus distinguendus (Förster), was also found to harbor two cryptic species with n = 5 and 6. Moreover, a morphometric study of these karyotypes suggested that the largest chromosome in the set with n = 5 has resulted from a fusion of two particular chromosomes in the karyotype with n = 6, and this hypothesis was confirmed using microdissection and whole‐chromosome painting. Recent cytogenetic and bioinformatic research also showed that N. vitripennis, Nasonia longicornis Darling, Nasonia giraulti Darling, Nasonia oneida Raychouhury et Desjardins, Muscidifurax uniraptor Kogan et Legner, and Trichomalopsis sarcophagae (Gahan) (all Pteromalidae) share the TTATTGGG telomeric motif with most other Chalcidoidea. Perspectives of the chromosome study of Pteromalidae s.l. are briefly discussed. [ABSTRACT FROM AUTHOR]

Introduction: The mechanism of relapsed CD19(−) B‐ALL after anti‐CD19 immunotherapy (Kymriah [CART‐19] and blinatumomab) is under active investigation. Our study aims to assess LILRB1 as a novel B‐cell marker for detecting CD19(−) B‐lymphoblasts and to analyze the clinicopathologic/genetic features of such disease to provide biological insight into relapse. Methods: Six patients (3 males/3 females, median age of 14 years) with relapsed CD19(−) B‐ALL were analyzed for cytogenetic/genetic profile and immunophenotype. Results: CD19(−) B‐ALL emerged after an interval of 5.8 months following anti‐CD19 therapy. Five of six patients had B‐cell aplasia, indicative of a persistent effect of CART or blinatumomab at relapse. Importantly, LILRB1 was variably expressed on CD19(−) and CD19(+) B lymphoblasts, strong on CD34(+) lymphoblasts and dim/partial on CD34(−) lymphoblasts. Three of six patients with paired B‐ALL samples (pre‐ and post‐anti‐CD19 therapy) carried complex and different cytogenetic abnormalities, either as completely different or sharing a subset of cytogenetic abnormalities. Conclusion: LILRB1 can be used as a novel B‐cell marker to identify CD19(−) B lymphoblasts. The emergence of CD19(−) B‐ALL appears to be associated with complex cytogenetic evolutions. The mechanism of CD19(−) B‐ALL relapse under anti‐CD19 immune pressure remains to be explored by comprehensive molecular studies. [ABSTRACT FROM AUTHOR]

Introduction: Passeriformes has the greatest species diversity among Neoaves, and the Tyrannidae is the richest in this order with about 600 valid species. The diploid number of this family remains constant, ranging from 2n = 76 to 84, but the chromosomal morphology varies, indicating the occurrence of different chromosomal rearrangements. Cytogenetic studies of the Tyrannidae remain limited, with approximately 20 species having been karyotyped thus far. This study aimed to describe the karyotypes of two species from this family, Myiopagis viridicata and Sirystes sibilator. Methods: Skin biopsies were taken from each individual to establish fibroblast cell cultures and to obtain chromosomal preparations using the standard methodology. The chromosomal distribution of constitutive heterochromatin was investigated by C-banding, while the location of simple repetitive sequences (SSRs), 18S rDNA, and telomeric sequences was found through fluorescence in situ hybridization. Results: The karyotypes of both species are composed of 2n = 80. The 18S rDNA probes hybridized into two pairs of microchromosomes in M. viridicata, but only a single pair in S. sibilator. Only the telomeric portions of each chromosome in both species were hybridized by the telomere sequence probes. Most of the SSRs were found accumulated in the centromeric and telomeric regions of several macro- and microchromosomes in both species, which likely correspond to the heterochromatin-rich regions. Conclusion: Although both species analyzed showed a conserved karyotype organization (2n = 80), our study revealed significant differences in their chromosomal architecture, rDNA distribution, and SSR accumulation. These findings were discussed in the context of the evolution of Tyrannidae karyotypes. [ABSTRACT FROM AUTHOR]

Hexaploid tritordeum [×Tritordeum martinii A. Pujadas (Poaceae) nothosp. nov.; HchHchAABB] resulted from crosses between wild barley (Hordeum chilense Roem et. Schultz) and durum wheat [Triticum turgidum L. ssp. durum (Desf.) Husn.]. Tritordeum (HT) presents interesting agronomic traits that can be transferred to cultivated wheat. Through the years, several HT lines were developed and characterised. Genomic stability and fertility are expected for advanced HT lines with multiple self‐fertilisation generations. In this work, we analysed the meiotic chromosomal pairing in pollen mother cells (PMCs) of three advanced lines of hexaploid tritordeum (HT9, HT31 and HT67) after fluorescence in situ hybridisation (FISH) performed with genomic DNA from H. chilense and the bread wheat cloned rDNA sequence, pTa71, as probes, and characterised nine morphological and yield‐related traits for three consecutive years in adult plants. As expected, all HT lines showed regular meiotic chromosomal pairing, ensuring plant fertility as previously confirmed by the characterisation of morphological and yield‐related traits in adult plants of preceding generations. Globally, tritordeum is interesting for wheat breeding and has potential as an alternative crop. [ABSTRACT FROM AUTHOR]

Comprising more than 100 species, Crenicichlina encompasses 20% of the taxonomic diversity of Neotropical cichlids and is widely distributed throughout Brazilian watersheds. A new hypothesis about the phylogeny of pike cichlids has recently been proposed, based on morphological and molecular characters, and new genera were created. We analyzed 18 species of four genera of Crenicichlina, collected in the Amazon, Iguaçu, Paraná and Uruguay River basins, using conventional and molecular cytogenetics. We present new cytogenetic data for nine species of pike cichlid, the chromosomal mapping of 5S rDNA for Crenicichla and other three species (Lugubria cincta, L. lugubris and Saxatilia semicincta), including available review of cytogenetic studies in Crenicichlina. Cytogenetic data for Crenicichla show a conserved cytotaxonomic pattern for most of the analyzed species: single 5S and 18S rDNA sites always in interstitial position centromeric heterochromatin. Lugubria showed greater variation in chromosomal characters, mainly an increase in 18S rDNA sites, always in terminal position and associated with heterochromatin. On the other hand, Saxatilia showed the same 18S rDNA pattern as Crenicichla, but with the presence of multiple 5S rDNA sites. Finally, karyotype of one species of Wallaciia that was analyzed possessed single 5S rDNA sites and multiple NORs. Although some chromosomal characters are conserved in Cichlinae, interspecific differences were verified in the karyotypic composition, as possible intragenus patterns. Chromosomal characters, mainly 5S and 18S rDNA, proved to diagnose species as well as they contribute to phylogenetic studies in pike cichlids. [ABSTRACT FROM AUTHOR]

Simple Summary: Chromosome changes represent important events in evolution. They may trigger processes of speciation or be the result of phylogenetic diversification. In both cases they can represent discrete evolutionary markers of taxonomic significance. In this contribution, we performed a comparative cytogenetic analysis on several representatives of the Malagasy ground geckos of the genus Paroedura. Our results show that chromosome variability in this genus involves chromosome number, morphology, and the independent differentiation of sex chromosome systems in distinct evolutionary lineages. We also highlight that the taxonomic, genetic and chromosome diversity in Paroedura is still underestimated. We present a comparative chromosome study of several taxa of the Malagasy ground geckos of the Paroedura bastardi and P. picta species groups. We employed a preliminary molecular analysis using a trait of the mitochondrial 16S rRNA gene (of about 570 bp) to assess the taxonomic status of the samples studied and a cytogenetic analysis with standard karyotyping (5% Giemsa solution), silver staining (Ag–NOR staining) and sequential C-banding (C-banding + Giemsa and + fluorochromes). Our results show that all the taxa studied of the P. bastardi group (P. ibityensis, P. rennerae and P. cf. guibeae) have a similar karyotype composed of 2n = 34 chromosomes, with two metacentric pairs (1 and 3) and all other pairs being acrocentric. Chromosome diversification in the P. bastardi group was mainly linked to the diversification of heteromorphic sex chromosome systems (ZZ/ZW) in P. ibityensis and P. rennerae, while no heteromorphic sex chromosome pair was found in P. cf. guibeae. The two taxa investigated of the P. picta species group (here named P. picta and P. cf. picta based on molecular data) showed the same chromosome number of 2n = 36, mostly acrocentric elements, but differed in the number of metacentric elements, probably as a result of an inversion at chromosome pair 2. We highlight that the genus Paroedura is characterized by the independent diversification of heterogametic sex chromosomes in different evolutionary lineages and, similarly to other phylogenetically related gecko genera, by a progressive formation of a biarmed element by means of tandem fusions and inversions of distinct pairs. [ABSTRACT FROM AUTHOR]

The sex chromosomes of skinks are usually poorly differentiated and hardly distinguished by cytogenetic methods. Therefore, identifying sex chromosomes in species lacking easily recognizable heteromorphic sex chromosomes is necessary to fully understand sex chromosome diversity. In this paper, we employed cytogenetics, sex quantification of genes, and transcriptomic approaches to characterize the sex chromosomes in Plestiodon elegans. Cytogenetic examination of metaphases revealed a diploid number of 2n = 26, consisting of 12 macrochromosomes and 14 microchromosomes, with no significant heteromorphic chromosome pairs, speculating that the sex chromosomes may be homomorphic or poorly differentiated. The results of the sex quantification of genes showed that Calumenin (calu), COPI coat complex subunit γ 2 (copg2), and Smoothened (smo) were at half the dose in males as in females, suggesting that they are on the X chromosome. Transcriptomic data analysis from the gonads yielded the excess expression male-specific genes (n = 16), in which five PCR molecular markers were developed. Restricting the observed heterozygosity to males suggests the presence of homomorphic sex chromosomes in P. elegans, XX/XY. This is the first breakthrough in the study of the sex chromosomes of Plestiodon. [ABSTRACT FROM AUTHOR]