The role of jigsaw karyotype analysis in the teaching of chromosomal recognition / 中华医学遗传学杂志

Karyotype analysis is the basic method in cytogenetics, and is also recognized as the "gold standard" for diagnosing chromosomal disorders. The teaching and training for traditional karyotyping analysis is time-consuming and even boring. The individual's ability for mastering the chromosome morphology can vary greatly. Therefore, it is necessary to improve the teaching method. On the basis of the traditional method, we have added auxiliary analysis software during the teaching. This type of splicing karyotype teaching has increased the students' interest and improved their ability for karyotyping, allowing them to quickly remember the characteristic bands of chromosomes. Through enhanced memory of a large number of karyotypic images, the students' ability to recognize individual chromosomes has improved.

Profiling of genetic mutations among adult Filipino patients diagnosed with Acute Myeloid Leukemia using fluorescence in situ hybridization from 2014 to 2021: A single-institution study

INTRODUCTION@#Among patients with Acute Myeloid Leukemia (AML), the karyotype at diagnosis is an important prognostic indicator for predicting outcomes. Several studies have been done to identify the most common cytogenetic abnormalities seen in patients in other countries, however, limited studies have been done in our setting.@*OBJECTIVE@#The study aims to determine the most common abnormalities present among patients with AML referred for Fluorescence in situ Hybridization (FISH) at the National Kidney and Transplant Institute.@*METHODOLOGY@#The study included 131 adult patients with a mean age o 46. Fluorescence in situ Hybridization was used to identify the following cytogenetic abnormalities: t(8;21), 11q23 (MLL), 16q22 (CBFB-MYH11), t(15;17) (PML/RARA), t(9;22) (BCR/ABL), 7q31 deletion, and Monosomy 7.@*RESULTS@#FISH was negative in 40% (n=53) of patients. 7q31 deletion is the most frequently identified cytogenetic abnormality among patients with a single abnormality (n=17, 13%) present and is the most frequently identified abnormality among patients with multiple abnormalities (n=26). 7q31 deletion is more frequently observed among patients between the ages 51 to 60 years old and among patients with AML with monocytic differentiation. 22% (n=29) of patients have multiple abnormalities, with the most common abnormalities to occur together are 7q31 deletion and t(8;21) (n=20, 15%). Patients with negative results and patients with multiple cytogenetic abnormalities are commonly seen within the 41 to 50 age group.@*CONCLUSION@# The current study provides a single-institution view of the cytogenetic abnormalities among adult Filipino patients with AML using FISH. Further investigation on the clinical history of these patients, with correlation with other methods, as well as epidemiologic studies are needed to better understand the similarities and differences seen from previously reported incidences.

Aspectos citogenéticos y moleculares en los síndromes mielodisplásicos / Cytogenetic and molecular aspects in myelodysplastic syndromes

Introducción: Los síndromes mielodisplásicos constituyen un grupo heterogéneo de alteraciones de la célula progenitora hematopoyética. Estos se caracterizan por presentar una médula ósea hipercelular, una hematopoyesis inefectiva, displasia y citopenia periférica y la posibilidad de evolución a leucemia mieloide aguda. Objetivo: Describir las alteraciones citogenéticas y moleculares más frecuentes de los síndromes mielodisplásicos. Métodos: Se realizó una revisión de la literatura en los idiomas inglés y español, a través del sitio web PubMed y el motor de búsqueda Google académico, de artículos publicados en los últimos cinco años. Se realizó análisis y resumen de la bibliografía. Análisis y síntesis de la información: En los síndromes mielodisplásicos están presentes alteraciones citogenéticas frecuentes como la deleción de los cromosomas 5q, 7q y 20q, la monosomía del cromosoma 7, la trisomía del cromosoma 8 y la presencia de cariotipos complejos, que, unido a mutaciones somáticas en diferentes genes, intervienen en la patogénesis de la enfermedad y su conocimiento permite la estratificación pronóstica de los pacientes. Conclusiones: El diagnóstico a través de los estudios citogenéticos convencionales, la hibridación in situ por fluorescencia y la secuenciación génica permite una mayor comprensión de la biología de la enfermedad, la estratificación del riesgo y la toma de decisiones terapéuticas(AU)

Introduction: Myelodysplastic syndromes constitute a heterogeneous group of alterations of the hematopoietic progenitor cell, characterized by hypercellular bone marrow, ineffective hematopoietic, dysplasia and peripheral cytopenia; and the possibility of progressing to acute myeloid leukemia. Objective: To describe the most frequent cytogenetic and molecular alterations of myelodysplastic syndromes. Methods: A review of the literature in English and in Spanish was carried out, in the PubMed website and using the search engine Google, for articles published in the last five years. We performed analysis and summary of the reviewed bibliography. Analysis and synthesis of information: In myelodysplastic syndromes, frequent cytogenetic alterations are present such as deletion of chromosomes 5q, 7q and 20q, as well as the monosomy of chromosome 7, trisomy of chromosome 8 and the presence of complex karyotypes, which together with somatic mutations in different genes intervene in the pathogenesis of the disease and allow prognostic stratification of patients. Conclusions: Diagnosis through conventional cytogenetic studies, fluorescence in situ hybridization and gene sequencing allow a better understanding of the biology of the disease, risk stratification and therapeutic decision making(AU)

Tracking the evolutionary pathways among Brazilian Lebiasina species (Teleostei: Lebiasinidae): a chromosomal and genomic comparative investigation

Despite several difficulties in chromosomal analyses of small-sized fishes, the cytogenetics of the Lebiasinidae was largely improved in the last years, showing differential patterns in the chromosomal evolution inside the family. In this context, it has been shown that genus Lebiasina preserves its karyotypic macrostructure, composed of 2n = 36 chromosomes, whereas the other genera generally present higher 2n. This study focused on the comparative cytogenetics of three Lebiasina species, one of them analyzed here for the first time, using conventional and molecular procedures. The results reinforced the differentiated evolutionary path of the genus Lebiasina while, at the same time, highlighted the genomic particularities that have accompanied the evolution of each species. In this sense, the repetitive components of the genome played a significant role in the differentiation of each species. It is also notable that L. minuta and L. melanoguttata, the two species that occur exclusively in the Brazilian territory, show greater chromosomal similarities to each other than to the trans-Andean sister species, L. bimaculata.(AU)

Apesar das dificuldades encontradas em se realizar análises cromossômicas em peixes de pequeno porte, os estudos citogenéticos em Lebiasinidae vêm crescendo nos últimos anos e demonstrando padrões diferenciados na evolução cromossômica entre os membros da família. Nesse contexto, o gênero Lebiasina tem mostrado preservar sua macroestrutura cariotípica, composta por 2n = 36 cromossomos, enquanto os demais gêneros geralmente apresentam 2n maiores. Este estudo tem como foco a citogenética comparativa de três espécies de Lebiasina, sendo uma delas analisada pela primeira vez aqui, através do emprego de técnicas convencionais e moleculares. Os resultados obtidos reforçam a trajetória evolutiva diferenciada do gênero Lebiasina, ao mesmo tempo em que evidenciam as particularidades genômicas que acompanham a evolução de cada uma das espécies. Neste contexto, os componentes repetitivos do genoma tiveram um papel importante na caracterização particular de cada uma das espécies. Também, é notável que L. minuta e L. melanoguttata, duas espécies que ocorrem exclusivamente no território brasileiro, apresentam maior proximidade citogenética entre elas do que com a espécie irmã transandina, L. bimaculata.(AU)

Clinical and genetic characteristics of patients with newly diagnosed acute promyelocytic leukemia: a single-center retrospective of 790 cases / 中华血液学杂志

Objective: To retrospectively analyze the data of Chinese patients with newly diagnosed acute promyelocytic leukemia (APL) to preliminarily discuss the clinical and cytogenetic characteristics. Methods: From February 2004 to June 2020, patients with newly diagnosed APL aged ≥ 15 years who were admitted to the Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Science & Peking Union Medical College were chosen. Clinical and laboratory features were retrospectively analyzed. Results: A total of 790 cases were included, with a male to female ratio of 1.22. The median age of the patients was 41 (15-76) years. Patients aged between 20 and 59 predominated, with 632 patients (80%) of 790 patients classified as low and intermediate risk and 158 patients (20%) of 790 patients classified as high risk. The white blood cell, platelet, and hemoglobin levels at diagnosis were 2.3 (0.1-176.1) ×10(9)/L, 29.5 (2.0-1220.8) ×10(9)/L, and 89 (15-169) g/L, respectively, and 4.8% of patients were complicated with psoriasis. The long-form type of PML-RARα was most commonly seen in APL, accounting for 58%. Both APTT extension (10.3%) and creatinine>14 mg/L (1%) are rarely seen in patients at diagnosis. Cytogenetics was performed in 715 patients with newly diagnosed APL. t (15;17) with additional chromosomal abnormalities were found in 155 patients, accounting for 21.7%; among which, +8 was most frequently seen. A complex karyotype was found in 64 (9.0%) patients. Next-generation sequencing was performed in 178 patients, and 113 mutated genes were discovered; 75 genes had an incidence rate>1%. FLT3 was the most frequently seen, which accounted for 44.9%, and 20.8% of the 178 patients present with FLT3-ITD. Conclusions: Patients aged 20-59 years are the most common group with newly diagnosed APL. No obvious difference was found in the ratio of males to females. In terms of risk stratification, patients divided into low and intermediate risk predominate. t (15;17) with additional chromosomal abnormalities accounted for 21% of 715 patients, in which +8 was most commonly seen. The long-form subtype was most frequently seen in PML-RARα-positive patients, and FLT3 was most commonly seen in the mutation spectrum of APL.

Técnicas de citogenética y biología molecular para el diagnóstico y seguimiento de la leucemia promielocítica / Cytogenetic and molecular biology techniques for the diagnosis and monitoring of promyelocytic leukemia

Introducción: La leucemia promielocítica es un subtipo de leucemia mieloide aguda que se presenta frecuentemente con una coagulopatía potencialmente mortal, por lo que representa una emergencia médica. En la gran mayoría de los pacientes ocurre la t(15;17)(q24;q21) que genera el gen aberrante PML-RARA. Mediante diferentes técnicas de citogenética y de la biología molecular que detectan dichas aberraciones es posible diagnosticar la entidad de manera inequívoca y estudiar la enfermedad mínima residual. Objetivo: Describir, comparar y analizar las técnicas de citogenética y de la biología molecular que son útiles para el diagnóstico y el seguimiento del paciente con leucemia promielocítica. Así como señalar sus ventajas y limitaciones. Métodos: Se realizó revisión de la bibliografía científica de los últimos cinco años relacionada con el tema a través de PUBMED. Se realizó análisis y resumen de la información. Análisis y síntesis de la información: Se describen dos técnicas de citogenética y tres moleculares basadas en la aplicación de la reacción en cadena de la polimerasa. Se comparan y analizan sus ventajas y limitaciones. Conclusiones: Algunas de estas técnicas son útiles únicamente para el diagnóstico, mientras que otras, por su alta sensibilidad, se recomiendan para el seguimiento del paciente con leucemia promielocítica(AU)

Introduction: Promyelocytic leukemia (PML) is a subtype of acute myeloid leukemia that frequently presents with a potentially fatal coagulopathy, therefore it represents a medical emergency. In the vast majority of patients, the t (15; 17) (q24; q21) occurs, which generates the aberrant gene PML-RARA. Using different cytogenetic and molecular biology techniques that detect these aberrations, it is possible to unequivocally diagnose the entity and study minimal residual disease. Objective: To describe, compare and analyze cytogenetics and molecular biology techniques that are useful for diagnosis and follow-up of the patient with Promyelocytic leukemia. As well as pointing out its advantages and limitations. Methods: A review of the scientific bibliography of the last five years related to the subject was carried out through PUBMED. An analysis and summary of the information was made. Analysis and synthesis of the information: Two cytogenetic and three molecular techniques are described based on the application of the polymerase chain reaction. Its advantages and limitations are compared and analyzed. Conclusions: Some of these techniques are only useful for diagnosis, while others, due to their high sensitivity, are recommended for monitoring the patient with Promyelocytic leukemia(AU)

Leucemia mieloide aguda: influencia pronóstico de algunos biomarcadores y la respuesta terapéutica en los pacientes menores de 60 años / Acute myeloid leukemia: prognostic influence of some biomarkers and the therapeutic response in patients under 60 years of age

Introducción: La leucemia mieloide aguda es una enfermedad clonal, reconocida como una de las hemopatías malignas más heterogénea en la que determinados biomarcadores clínicos, inmunológicos, citogenéticos y moleculares influyen en la respuesta de los pacientes al tratamiento. Objetivo: Describir la influencia pronóstico de biomarcadores inmunológicos, citogenéticos y moleculares en la respuesta terapéutica en los pacientes adultos menores de 60 años con leucemia mieloide aguda. Métodos: Se realizó una revisión exhaustiva del tema en bases de datos como: Pubmed, Scielo, ScienceDirect, Medline y el motor de búsqueda Google académico; se utilizaron como referencia artículos actualizados publicados principalmente en los últimos cinco años. Análisis y síntesis de la información: La heterogeneidad inmunológica, citogenética y molecular de los pacientes adultos menores de 60 años con leucemia mieloide aguda se relaciona con la variabilidad en la respuesta al tratamiento que tienen los enfermos y repercute en la supervivencia global y libre de enfermedad. Conclusión: Sobre la base a características inmunológicas, citogenéticas y moleculares es posible establecer el pronóstico de los pacientes con leucemia mieloide aguda, lo cual permite seleccionar la terapéutica adecuada para disminuir en lo posible las complicaciones, las recaídas y aumentar la supervivencia global(AU)

Introduction: Acute myeloid leukemia is a clonal disease, recognized as one of the most heterogeneous malignant hemopathy in which certain clinical, immunological, cytogenetic and molecular biomarkers influence the response of patients to treatment. Objective: Describe the prognostic influence of immunological, cytogenetic and molecular biomarkers on the therapeutic response in adult patients under 60 years of age with acute myeloid leukemia. Methods: An exhaustive review was conducted about the topic in the databases as Pubmed, Scielo, ScienceDirect, Medline and Scholar Google, for which papers mainly published in the last five years were used as reference. Analysis and synthesis of the information: The immunological, cytogenetic and molecular heterogeneity of adult patients under 60 years of age with acute myeloid leukemia is related to the variability in the response to treatment that patients have and affects their overall and disease-free survival. Conclusions: Based on the immunological, cytogenetic and molecular characteristics, it is possible to establish the prognosis of patients with acute myeloid leukemia, which allows selecting the appropriate therapy to reduce complications, relapses as much as possible and increase overall survival(AU)

Hallazgos moleculares y citogenéticos en pacientes pediátricos, diagnosticados de leucemia linfoide aguda: Un estudio de centro único / Molecular and cytogenetic findings in pediatric patients diagnosed with acute lymphoid leukemia: A single center study / Achados moleculares e citogenéticos em pacientes pediátricos com diagnóstico de leucemia linfóide aguda: um estudo de centro único

Introducción: La leucemia linfoblástica aguda (LLA) es la neoplasia maligna de mayor frecuencia en la infancia; advertir sus alteraciones moleculares y citogenéticas permite establecer el riesgo, el pronóstico asociado y además plantear esquemas terapéuticos apropiados; el objetivo de este estudio es conocer la prevalencia de estas alteraciones en nuestra población. Metodología: Estudio de tipo retrospectivo y transversal, basado en los registros de las alteraciones moleculares y citogenéticas de los pacientes pediátricos diagnosticados con leucemia linfoblástica aguda durante el periodo comprendido entre enero 2014 a diciembre de 2018, en el Hospital del Instituto Oncológico Nacional "Dr. Juan Tanca Marengo". Resultados: Se incluyeron 338 pacientes, de los cuales el principal grupo etario lo constituyo el de 0 a 4 años; el inmunofenotipo más observado fue el B-común. En el 24.56% de los casos se detectó altercaciones estructurales, principalmente por estudios de biología molecular; siendo la más común la translocación t(12;21). Se obtuvieron resultados por citogenética en 167 pacientes, en cuales la principal alteración numérica correspondió a la hiperdiploidía de entre 47 a 51 cromosomas. Conclusión: Los avances en la caracterización molecular y citogenética de la LLA, permiten mejorar la estratificación de su riesgo; y establecer estrategias terapéuticas que permitan una mejoría en la sobrevida.

Introduction: Acute lymphoblastic leukemia (ALL) is the most frequent malignant neoplasm in childhood; Noting its molecular and cytogenetic alterations allows to establish the risk, the associat-ed prognosis and also to propose appropriate therapeutic schemes; The objective of this study is to know the prevalence of these alterations in our population. Methods: Retrospective and cross-sectional study, based on the records of molecular and cytogenetic alterations of pediatric patients diagnosed with acute lymphoblastic leukemia during the period from January 2014 to December 2018, at the National Oncological Institute Hospital "Dr. Juan Tanca Marengo". Results: 338 patients were included, of which the main age group was made up of 0 to 4 years; the most observed immunophenotype was B-common. In 24.56% of the cases, structural alterations were detected, mainly by molecular biology studies; the most common being the t (12; 21) translocation. Cytogenetics results were obtained in 167 patients, in which the main numerical alteration corresponded to hyperdiploidy of between 47 and 51 chromosomes. Conclusions: Advances in the molecular and cytogenetic characterization of ALL make it possible to improve the stratification of its risk; and establish therapeutic strategies that achieve an improvement in survival.

Introdução: A leucemia linfoblástica aguda (LLA) é a neoplasia maligna mais comum na infância; Observar suas alterações moleculares e citogenéticas permite estabelecer o risco, o prognóstico associado e também propor esquemas terapêuticos adequados; O objetivo deste estudo é conhecer a prevalência dessas alterações em nossa população. Metodologia: Estudo retrospectivo e transversal, baseado nos registros de alterações moleculares e citogenéticas de pacientes pediátricos com diagnóstico de leucemia linfoblástica aguda no período de janeiro de 2014 a dezembro de 2018, no Hospital del Instituto Oncológico Nacional "Dr. Juan Tanca Marengo ". Resultados: Foram incluídos 338 pacientes, cuja faixa etária principal era de 0 a 4 anos; o imunofenótipo mais observado foi B-comum. Em 24,56% dos casos, foram detectadas alterações estruturais, principalmente por estudos de biologia molecular; o mais comum é a translocação t (12; 21). Os resultados citogenéticos foram obtidos em 167 pacientes, nos quais a principal alteração numérica correspondeu à hiperdiploidia entre 47 e 51 cromossomos. Conclusão: Os avanços na caracterização molecular e citogenética da LLA permitiram melhorar a estratificação de risco; e estabelecer estratégias terapêuticas que permitam uma melhora na sobrevida.

Leucemia linfoide crónica: aspectos citogenéticos y moleculares / Chronic Lymphoid Leukemia: cytogenetic and molecular aspects

Introducción: La leucemia linfoide crónica es un trastorno linfoproliferativo caracterizado por la acumulación de linfocitos pequeños de aspecto maduro en sangre periférica, médula ósea y tejidos linfoides con un período de vida prolongado. Presenta una gran variabilidad clínica y genética. Objetivo: Describir los aspectos citogenéticos y moleculares de la leucemia linfoide crónica. Métodos: Se realizó revisión de la literatura en inglés y español, a través del sitio web PubMed y el motor de búsqueda Google académico, de artículos publicados en los últimos 5 años. Se hizo un análisis y resumen de la bibliografía revisada. Desarrollo: En la leucemia linfoide crónica están presentes alteraciones citogenéticas frecuentes como la deleción de los cromosomas 13q, 11q y 17p, así como la trisomía 12, que unido al conocimiento del estado mutacional del gen de la región variable de la cadena pesada de la inmunoglobulina, y otras mutaciones somáticas en diferentes genes, así como a variables clínicas y de laboratorio permiten la estratificación pronóstica de los pacientes. Conclusiones: El diagnóstico a través de los estudios citogenéticos convencionales estimulados con mitógenos, la hibridación in situ por fluorescencia y la secuenciación génica permite una mayor comprensión de la biología de la enfermedad, así como tomar decisiones terapéuticas más personalizadas(AU)

Introduction: Chronic B lymphoid leukemia is a lymphoproliferative disorder characterized by the accumulation of small, mature-looking lymphocytes in peripheral blood, bone marrow and lymphoid tissues with a long life span. It has great clinical and genetic variability. Objective: To describe the cytogenetic and molecular aspects of the disease. Methods: A review of the literature in English and in Spanish was carried out, in the PubMed website and using the search engine of Google Scholar, for articles published in the last five years. We performed analysis and summary of the reviewed bibliography. Development: In chronic lymphoid leukemia, frequent cytogenetic alterations are present such as deletion of chromosomes 13q, 11q and 17p, as well as trisomy 12, which together with the knowledge of the mutational status of the gene for the variable region of the immunoglobulin heavy chain and other somatic mutations in different genes, as well as clinical and laboratory variables allows prognostic stratification of patients. Conclusions: Diagnosis through conventional mitogen-stimulated cytogenetic studies, fluorescence in situ hybridization and gene sequencing allow a better understanding of the biology of the disease, as well as making more personalized therapeutic decisions(AU)

Occurrence of euchromatic B chromosomes in natural populations of Moenkhausia bonita and M. forestii (Pisces: Characidae)

Moenkhausia is a highly specious genus among the Characidae, composed of 96 valid species. Only twelve species have a known karyotype. Thus, here are presented the first cytogenetic data of two allopatric populations of Moenkhausia bonita and one of M. forestii, both belonging to the upper Paraná River basin (PR) with discussion on the evolutionary and cytotaxonomic aspects of the genus. The two species presented 2n = 50 chromosomes but different karyotype formulas and occurrence of 1-2 B chromosomes. These elements are small metacentrics in M. bonita and small acrocentrics in M. forestii. In both species, B chromosomes were euchromatic. Ag-NOR sites were found in pair 3 (metacentric), coinciding with fluorescent in situ hybridization (FISH) by the 18S rDNA probe in both species. However, the species differed in terms of the number and position of 5S rDNA sites. Heterochromatic blocks, mapped in M. bonita showed the least amount of heterochromatin in the terminal and pericentromeric regions, while the M. forestii karyotype revealed a greater amount of interstitial heterochromatic blocks. The karyotype distinctions between the two species, including the morphology of B chromosomes, may contribute as a reference in the taxonomic studies in this group.(AU)

Moenkhausia é um gênero altamente especioso dentre os Characidae, composto por 96 espécies válidas, mas apenas doze espécies têm seus cariótipos conhecidos. Portanto, são apresentados aqui os primeiros dados citogenéticos de duas populações alopátricas de Moenkhausia bonita e uma de M. forestii, ambas pertencentes à bacia do alto rio Paraná (PR), com uma ampla discussão sobre os aspectos evolutivos e citotaxonômicos do gênero. As duas espécies apresentaram 2n = 50 cromossomos, mas diferentes fórmulas cariotípicas e ocorrência de 1-2 cromossomos B. Esses elementos são pequenos metacêntricos em M. bonita e acrocêntricos pequenos em M. forestii. Em ambas as espécies, os cromossomos B apresentaram-se eucromáticos. Sítios Ag-NOR foram encontrados no par 3 (metacêntrico), coincidindo com a hibridização fluorescente in situ (FISH) pela sonda 18S rDNA em ambas as espécies. No entanto, as espécies diferiram em termos de número e posição dos sítios de 5S rDNA. Blocos heterocromáticos mapeados em M. bonita revelaram pequena quantidade de heterocromatina nas regiões terminal e pericentromérica, enquanto o cariótipo de M. forestii revelou uma maior quantidade de blocos heterocromáticos intersticiais. As distinções cariotípicas entre as duas espécies, incluindo a morfologia dos cromossomos B, podem contribuir como uma referência em estudos taxonômicos neste grupo.(AU)

Chromosome analysis in Saccodon wagneri (Characiformes) and insights into the karyotype evolution of Parodontidae

Parodontidae is a relatively small group of Neotropical characiform fishes consisting of three genera (Apareiodon, Parodon, and Saccodon) with 32 valid species. A vast cytogenetic literature is available on Apareiodon and Parodon, but to date, there is no cytogenetic data about Saccodon, a genus that contains only three species with a trans-Andean distribution. In the present study the karyotype of S. wagneri was described, based on both conventional (Giemsa staining, Ag-NOR, C-bands) and molecular (repetitive DNA mapping by fluorescent in situ hybridization) methods. A diploid chromosome number of 2n = 54 was observed in both sexes, and the presence of heteromorphic sex chromosomes of the ZZ/ZW type was detected. The W chromosome has a terminal heterochromatin band that occupies approximately half of the long arm, being this band approximately half the size of the Z chromosome. The FISH assay showed a synteny of the 18S-rDNA and 5S-rDNA genes in the chromosome pair 14, and the absence of interstitial telomeric sites. Our data reinforce the hypothesis of a conservative karyotype structure in Parodontidae and suggest an ancient origin of the sex chromosomes in the fishes of this family.(AU)

Parodontidae é um grupo relativamente pequeno de peixes caraciformes neotropicais que consiste em três gêneros (Apareiodon, Parodon e Saccodon) com 32 espécies válidas. Uma vasta literatura citogenética está disponível sobre Apareiodon e Parodon, mas até o momento não há dados citogenéticos sobre Saccodon, um gênero que contém apenas três espécies com distribuição transandina. No presente estudo foi descrito o cariótipo de S. wagneri, baseado em métodos convencionais (coloração de Giemsa, Ag-NOR, bandas C) e moleculares (mapeamento de DNA repetitivo por hibridização fluorescente in situ). Um número cromossômico diplóide de 2n = 54 foi observado, e a presença de cromossomos sexuais heteromórficos do tipo ZZ/ZW foi revelada. O cromossomo W possui uma banda terminal heterocromática que ocupa aproximadamente metade do braço longo, sendo esta banda aproximadamente a metade do tamanho do cromossomo Z. O ensaio FISH mostrou uma sintenia dos genes 18S-rDNA e 5S-rDNA no par de cromossomos 14, e a ausência de sítios teloméricos intersticiais. Nossos dados reforçam a hipótese de uma estrutura cariotípica conservadora em Parodontidae e sugerem uma origem ancestral dos cromossomos sexuais nos peixes desta família.(AU)

Myelodysplastic syndrome in a 30-year-old man with coronavirus disease 2019 (COVID-19): a diagnostic challenge

Background Myelodysplastic syndromes (MDS) mainly occur in the elderly but can rarely affect younger individuals too. The correct diagnosis relies on careful morphologic evaluation, cytogenetic/molecular results, and excluding reactive conditions mimicking MDS. We present the clinical, pathologic, cytogenetic, and molecular features of a case of MDS with excess blasts-2 (MDS-EB-2) in a 30-year-old male who was found to have pancytopenia during his hospitalization for coronavirus disease 2019 (COVID-19) and discuss the diagnostic challenges of MDS in patients with COVID-19. Case presentation A 30-year-old man presented to an outside hospital with fever, chills, weakness, coughing spells, dizziness and shortness of breath and was diagnosed with bilateral pneumonia due to COVID-19. At the outside hospital, he was found to be pancytopenic, and a subsequent bone marrow aspiration and biopsy raised concern for a COVID-19 induced hemophagocytic lymphohistiocytosis. In addition, MDS could not be ruled out. The patient was thus referred to our institute for further management. The patient's peripheral blood showed pancytopenia with occasional dysplastic neutrophils and a few teardrop cells. Given the diagnostic uncertainty, a bone marrow aspiration and a biopsy were repeated revealing a hypercellular bone marrow with erythroid hyperplasia, megakaryocytic hyperplasia, trilineage dysplasia, increased blasts (13%), many ring sideroblasts, and mild to moderate myelofibrosis, consistent with MDS-EB-2. Chromosomal analysis revealed isochromosome 14. Next generation sequencing demonstrated SF3B1 K700E mutation. Discussion and conclusion The diagnosis of MDS can be challenging, particularly in young patients. Cytopenia and myelodysplastic features have been reported in COVID-19 patients, making the diagnosis of MDS more elusive. A careful pathologic examination of the bone marrow with ancillary studies including flow cytometry, immunohistochemistry, and cytogenetic and molecular studies in combination with a thorough clinical evaluation, leads to the accurate diagnosis.

Cytomolecular investigations using repetitive DNA probes contribute to the identification and characterization of Characidium sp. aff. C. vidali (Teleostei: Characiformes)

Characidium sp. aff. C. vidali is a species found in coastal streams in southeastern Brazil, which has karyotypic explanatory elements as the occurrence of microstructural variations, keeping the chromosomal macrostructure of the genus. The objective of this study was to apply cytomolecular tools in the chromosomes of Characidium sp. aff. C. vidali to identify characteristics in their karyotype contributing to cytogenetic definition of this species, adding information about the evolution of the chromosomal structure of the group. The species showed 2n = 50 chromosomes and from 1 to 4 additional B microchromosomes. FISH technique showed histone H3 and H4 genes in the short arm of pair 10, and microsatellites (CA)15, (CG)15, (GA)15 and (TTA)10 clustered in the subtelomeric portions of all A chromosomes, with total accumulation by supernumerary. The telomeric probe marked terminal regions of all chromosomes, in addition to the interstitial portion of four pairs, called ITS sites, with these markings being duplicated in two pairs, hence the double-ITS classification. C-banding revealed that supernumerary chromosomes are completely heterochromatic, that ITS sites are C-banding positive, but double-ITS sites are C-banding negative. So, throughout the evolution to Characidium, genomic events are occurring and restructuring chromosomes in populations.(AU)

Characidium sp. aff. C. vidali é uma espécie encontrada em riachos costeiros do sudeste do Brasil, que apresenta elementos cariotípicos elucidativos quanto à ocorrência de variações microestruturais, conservando a macroestrutura cromossômica do gênero. O objetivo deste estudo foi aplicar ferramentas citomoleculares para identificar características no cariótipo de Characidium sp. aff. C. vidali, que contribuam para a definição citogenética desta espécie, agregando informações quanto à evolução da estruturação cromossômica do grupo. A espécie apresentou 2n = 50 cromossomos, além de 1 a 4 microcromossomos B por célula. A FISH mostrou os genes de histona H3 e H4 sintênicos no braço curto do par 10, e os microssatélites (CA)15, (CG)15, (GA)15 e (TTA)10 clusterizados nas porções subteloméricas de todos os cromossomos do complemento A, com grande acúmulo nos supranumerários. A sonda telomérica identificou marcações terminais em todos os cromossomos, além de quatro pares marcados intersticialmente, chamados de sítios ITS, e dois pares com duas marcações intersticiais, chamados de double-ITS. O bandamento C revelou que os cromossomos supranumerários são completamente heterocromáticos, que os sítios ITS são banda C positivos, mas os sítios double-ITS são banda C negativos. Então, ao longo da evolução de Characidium, eventos genômicos estão ocorrendo e reestruturando cromossomos nas populações.(AU)

Integrative taxonomy reveals disjunct distribution and first record of Hoplias misionera (Characiformes: Erythrinidae) in the Amazon River basin: morphological, DNA barcoding and cytogenetic considerations

The Hoplias malabaricus group encompasses six valid species and still is believed to harbors cryptic diversity. In this work, an integrative approach including morphological, DNA barcoding, and cytogenetic considerations was conducted to characterize a population of H. malabaricus from the Amazon basin that was recently allocated in the same mitochondrial lineage with H. misionera, a species originally described from La Plata basin. The DNA barcoding analysis revealed that the Amazon population nested together with H. misionera specimens from the La Plata basin (BIN AAB1732) in the same cluster. The intragroup distance (0.5%) was 12 times lower than the nearest neighbor (6%) distance. The morphometric analysis demonstrated slightly variation between Amazon and La Plata populations, being the former composed by larger specimens. Further morphological data supported the molecular evidence of H. misionera inhabiting Amazon basin. The karyotype characterization of H. misionera in the Amazon population showed 2n=40 and karyotypic formulae 20m+20sm, that added to C-banding, Ag-NOR and 18S results are suggestive of the similarity to karyomorph C of H. malabaricus. This work reveals the first record of H. misionera outside of La Plata basin and expands the species distribution for 2500 km northward until the Marajó Island, estuary of Amazonas River.(AU)

O grupo Hoplias malabaricus compreende seis espécies válidas e ainda acredita-se que abriga diversidade críptica. Neste trabalho, uma abordagem integrativa incluindo considerações morfológicas, de DNA barcoding e de citogenética foi conduzida para caracterizar uma população de H. malabaricus da bacia amazônica que foi recentemente alocada na mesma linhagem mitocondrial de H. misionera, uma espécie originalmente descrita para a bacia La Plata. A análise molecular por DNA barcoding revelou que essa população amazônica forma um clado monofilético com espécimes de H. misionera provenientes da bacia La Plata (BIN AAB1732). A distância genética intragrupo (0,5%) é 12 vezes menor do que para o vizinho mais próximo (6%). A comparação morfométrica demonstrou pequena variação entre as populações amazônica e La Plata, sendo os primeiros ligeiramente maiores. Entretanto, os dados morfológicos corroboram com evidência molecular e confirmam a ocorrência de H. misionera na bacia amazônica. A caracterização cariotípica de H. misionera na população amazônica apresentou 2n=40 e fórmula cariotípica 20m+20sm, que aliada aos resultados de banda C, Ag-NOR e 18S sugerem que seja similar ao cariomorfo C de H. malabaricus. Esse trabalho revela o primeiro registro de H. misionera fora da bacia La Plata e estende a distribuição da espécie por mais de 2500 km ao Norte, até a Ilha do Marajó, estuário do rio Amazonas.(AU)

Molecular cytogenetics insights in two pelagic big-game fishes in the Atlantic, the tarpon, Megalops atlanticus (Elopiformes: Megalopidae), and the sailfish, Istiophorus platypterus (Istiophoriformes: Istiophoridae)

Some pelagic and usually large sized fishes are preferential targets for sport and commercial fishing. Despite their economic importance, cytogenetic data on their evolutionary processes and management are very deficient, especially due to logistical difficulties. Here, information for two of such charismatic species, the tarpon, Megalops atlanticus (Elopiformes: Megalopidae), and the sailfish, Istiophorus platypterus (Istiophoriformes: Istiophoridae), both with a wide Atlantic distribution, were provided. Cytogenetic data were obtained using conventional methods (Giemsa staining, Ag-NORs technique, and C-banding), base-specific fluorochrome staining and fluorescence in situ hybridization (FISH) with rDNA probes. Megalops atlanticus has 2n = 50 chromosomes, all acrocentric ones (NF = 50), while Istiophorus platypterus has 2n = 48 chromosomes, 2m + 2st + 44a (NF = 52). Megalops atlanticus populations from the South Atlantic and Caribbean share identical karyotypic patterns, likely associated with gene flow between them. In turn, I. platypterus presents karyotype similarities with phylogenetically close groups, such as Carangidae. The chromosomal characteristics of these species highlight their independent evolutionary paths. Additionally, the current data contribute to knowledge of new aspects of pelagic fish fauna and will support further comparative studies with congeneric species, clarifying evolutionary karyotype trends of these fish groups.(AU)

Alguns peixes pelágicos de grande porte são alvos preferenciais para a pesca esportiva e comercial. Apesar de sua importância econômica, os dados citogenéticos sobre seus processos evolutivos e de manejo são muito deficientes, principalmente devido às dificuldades logísticas. Aqui são apresentadas informações cromossômicas de duas espécies carismáticas, o tarpão, Megalops atlanticus (Elopiformes: Megalopidae), e o agulhão-vela, Istiophorus platypterus (Istiophoriformes: Istiophoridae), ambos com ampla distribuição no oceano Atlântico. Os dados citogenéticos foram obtidos usando métodos convencionais (coloração em Giemsa, técnica de Ag-NORs e bandamento C), coloração com fluorocromos específicos e hibridização fluorescente in situ (FISH) com sondas DNAr. Megalops atlanticus possui 2n = 50 cromossomos, todos acrocêntricos (NF = 50), enquanto Istiophorus platypterus possui 2n = 48 cromossomos, 2m + 2st + 44a (NF = 52). Populações de M. atlanticus do Atlântico Sul e Caribe compartilham padrões cariotípicos idênticos, provavelmente associados ao fluxo gênico entre regiões. Por sua vez, I. platypterus apresenta semelhanças cariotípicas micro e macroestruturais com grupos filogeneticamente próximos, como Carangidae. As características cromossômicas destas espécies destacam seus caminhos evolutivos independentes. Adicionalmente, os dados apresentados contribuem com novos aspectos da fauna pelágica e apoiarão futuros estudos comparativos com espécies congenéricas, esclarecendo as tendências evolutivas do cariótipo destes grupos de peixes.(AU)

Interim In vitro Dose-Response Curve for the Dicentric Biodosimeter Assay from a Philippine Radiotherapy Facility using a Linear Accelerator

@#Background. Accidental radiation exposure can occur anytime. Biodosimeters help in quantifying the absorbed dose of individuals who are not equipped with personal dosimeters during radiation exposure. The dicentric assay can quantify radiation damage by correlating radiation dose exposure with the frequency of dicentric chromosomes in the peripheral lymphocytes extracted from exposed individuals. Objective. The study aims to present the interim results of the reference dose-response curve for a Philippine radiotherapy facility constructed using a 6MV linear accelerator (ClinacX, Varian). Methods. Samples of peripheral blood from healthy volunteers were irradiated in a customized water phantom of doses 0.10 to 5.0 Gray using a linear accelerator. The irradiated samples were cultured and analyzed following the International Atomic Energy Agency Cytogenetic Dosimetry Protocol (2011) with modifications. Linear-quadratic model curve fitting and further statistical analysis were done using CABAS (Chromosome Aberration Calculation Software Version 2.0) and Dose Estimate (Version 5.2). Interim results of the samples were used to generate these curves. Results. The dose-response curve generated from the preliminary results were comparable to published dose response curves from international cytogenetic laboratories. Conclusion. The generated dose-response calibration curve will be useful for medical triage of the public and radiologic staff accidentally exposed to radiation during medical procedures or in the event of nuclear accidents.

Clinical and Cytogenetical Characteristics in Acute Myeloid Leukemia with Myelodysplasia-Related Changes / 中国实验血液学杂志

OBJECTIVE@#To explore the clinical and cytogenetic characteristics of acute myeloid leukemia with myelodysplasia-related changes (AML-MRC) based on morphology define.@*METHODS@#A total of 180 newly diagnosed acute myeloid leukemia (AML) patients were enrolled and retrospectively analyzed, and marrow cell morphology of 126 patients were re-evaluated. The clinical and cytogenetic characteristics, including ages, sex, WBC count, HGB level, PLT count, blasts percentage, abnormal karyotype detection rate of the patients in AML with multilineage dysplasia (AML-MRC-1), secondary AML from myelodysplastic/ myeloproliferative neoplasms (MDS/MPN) (AML-MRC-2), and AML not otherwise specified (AML-NOS) groups were investigated.@*RESULTS@#There was no significant differences between the patients in three groups in terms of sex, age and platelet count (P=0.898, P=0.365, P=0.853), but AML-MRC-2 group (73.2%) was higher than AML-MRC-1 (60.0%) and AML-NOS (56.4%) in the percentages of patients over 60 years old (P=0.228); there were statistically significant differences on WBC count, HGB level, and blasts percentage (P=0.000, P=0.022, P=0.000, AML-MRC-2

Cytogenetic and molecular genetic analysis of three cases with small supernumerary marker chromosomes / 中华医学遗传学杂志

OBJECTIVE@#To delineate the origin and structure of 3 cases of small supernumerary marker chromosomes (sSMCs) through cytogenetic and molecular genetic analysis.@*METHODS@#Conventional G, C and N banding were carried out to analyze the chromosomal karyotypes. Chromosomal microarray analysis (CMA) and fluorescence in situ hybridization (FISH) were used to delineate the origin and structure of the sSMCs.@*RESULTS@#In case 1, chromosomal karyotype of peripheral blood sample was 47,XY,+mar. This de novo sSMC was a dual-satellited dicentric inverted duplicated marker chromosome, for which CMA yielded a normal result. It was predicted to not increase the risk of offspring. In case 2, the fetal chromosomal karyotype was 47,XY,+mar[17]/46,XY[33]. Chromosomal banding suggested that this de novo segment contained euchromatin, and the result of CMA was arr[hg19] 5p12q11.1(45 694 574-49 475 697) × 3. FISH showed the sSMC to be a fragment derived from 5p12 containing the HCN1 gene. Case 3 was found to have a fetal karyotype of 45,XY,-13[25]/46,XY,r(13)[18]/46,XY,-13,+mar[7]. Both parents had refused further examination.@*CONCLUSION@#Conventional chromosomal banding combined with molecular methods can delineate the origin and structure of the sSMCs, which can help with prediction of their pathogenicity and facilitate genetic counseling.