Cytogenetic and Genome Research最新文献

{"title":"Clinical Findings in a Series of Thirty Eight Patients with Williams-Beuren Syndrome.","authors":"Karina Montemor Klegen de Oliveira, Luiza de Oliveira Simões, Ana Mondadori Dos Santos, Carlos Eduardo Steiner","doi":"10.1159/000540941","DOIUrl":"10.1159/000540941","url":null,"abstract":"<p><strong>Introduction: </strong>Williams-Beuren syndrome is a contiguous gene syndrome caused by microdeletion of the locus 7q11.23. It is a clinically recognizable condition whose cardinal features include growth deficiency, variable degrees of neurodevelopmental disorders, congenital cardiac defects, outgoing personality, and typical facies. Case Series Presentation: This retrospective study analyzed 38 consecutive patients in a single center for rare diseases, diagnosed by Preus criteria modified by the Sugayama scoring system, comprising 17 male and 21 female individuals aged 1 month to 55 years. Cases were divided into two groups concerning (a) exclusive clinical diagnosis or (b) clinical diagnosis followed by a laboratory cytogenetic or cytogenomic test; except for hypertension, no significant difference was seen among both groups. The most frequent findings were intellectual deficiency, developmental delay, typical facies, and overfriendliness, all above 80% of the total sample. On the other hand, supravalvar aortic stenosis was found in only 32.4%, while other congenital heart diseases were seen in 56.7% of the sample. Unusual features included one individual with 13 pairs of ribs, another with unilateral microphthalmia, and three with unilateral renal agenesis. Comorbidities comprised 9 cases of hypothyroidism and 1 case each of precocious puberty, segmental vitiligo, type 1 diabetes mellitus, and congenital adrenal hyperplasia.</p><p><strong>Conclusion: </strong>Preus criteria modified by the Sugayama scoring system are still efficient and helpful for clinical diagnosis. This is the second report on microphthalmia and the first study describing the association between vitiligo, type 1 diabetes mellitus, and congenital adrenal hyperplasia in individuals with Williams-Beuren syndrome.</p>","PeriodicalId":11206,"journal":{"name":"Cytogenetic and Genome Research","volume":" ","pages":"139-147"},"PeriodicalIF":1.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142003856","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative Cytogenetics in Tyrannidae (Aves, Passeriformes): High Genetic Diversity despite Conserved Karyotype Organization.","authors":"Diego Madruga Saraiva, Marcelo Santos de Souza, Victoria Tura, Vitor Oliveira de Rosso, Edison Zefa, Analía Del Valle Garnero, Ricardo José Gunski, Francisco de Menezes Cavalcante Sassi, Marcelo de Bello Cioffi, Rafael Kretschmer","doi":"10.1159/000538586","DOIUrl":"10.1159/000538586","url":null,"abstract":"<p><strong>Introduction: </strong>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.</p><p><strong>Methods: </strong>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.</p><p><strong>Results: </strong>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.</p><p><strong>Conclusion: </strong>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.</p>","PeriodicalId":11206,"journal":{"name":"Cytogenetic and Genome Research","volume":" ","pages":"43-51"},"PeriodicalIF":1.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140317991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First Karyotypic Insights into Potamotrygon schroederi Fernández-Yépez, 1958: Association of Different Classes of Repetitive DNA.","authors":"Alex M V Ferreira, Patrik F Viana, Leandro Marajó, Eliana Feldberg","doi":"10.1159/000539331","DOIUrl":"10.1159/000539331","url":null,"abstract":"<p><strong>Introduction: </strong>Currently, there are 38 valid species of freshwater stingrays, and these belong to the subfamily Potamotrygoninae. However, cytogenetic information about this group is limited, with studies mainly using classical techniques, Giemsa, and C-banding.</p><p><strong>Methods: </strong>In this study, we used classical and molecular cytogenetic techniques - mapping of 18S and 5S rDNA and simple sequence repeats (SSRs) - in order to investigate the karyotypic composition of Potamotrygon schroederi and reveal the karyoevolutionary trends of this group.</p><p><strong>Results: </strong>The species presented 2n = 66 chromosomes with 18m + 12sm + 16st + 20a, heterochromatic blocks distributed in the centromeric regions of all the chromosomes, and terminal blocks in the q arm of pairs 2 and 3. Mapping of 18S rDNA regions revealed multiple clusters on pairs 2 and 7 and a homolog of pair 24. The 5S rDNA region was found in the pericentromeric portion of the subtelocentric pair 16. Furthermore, dinucleotide SSRs sequences were found in the centromeric and terminal regions of different chromosomal pairs, with preferential accumulation in pair 17. In addition, we identified conspicuous blocks of (GATA)n and (GACA)n sequences colocalized with the 5S rDNA (pair 16).</p><p><strong>Conclusion: </strong>In general, this study corroborates the general trend of a reduction in 2n in the species of Potamotrygoninae subfamily. Moreover, we found that the location of rDNA regions is very similar among Potamotrygon species, and the SSRs accumulation in the second subtelocentric pair (17) seems to be a common trait in this genus.</p>","PeriodicalId":11206,"journal":{"name":"Cytogenetic and Genome Research","volume":" ","pages":"60-68"},"PeriodicalIF":1.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140921406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Parental Centromere Sizes Remain Unaltered in Allopolyploid Wheat-Rye Hybrids.","authors":"Elena V Evtushenko, Sima S Gatzkaya, Petr I Stepochkin, Alexander V Vershinin","doi":"10.1159/000541705","DOIUrl":"10.1159/000541705","url":null,"abstract":"<p><strong>Introduction: </strong>In chromatin nucleosomes, the presence - instead of canonical histone H3 - of its variant, CENH3 (in plants), is considered the most reliable marker of the location of centromeres. In this study, we investigated the effects of distant hybridization and maternal cytoplasm on centromere size in allopolyploid hybrids between wheat and rye as compared to their parental forms.</p><p><strong>Methods: </strong>Centromere sizes were measured using 2D images of CENH3 fluorescent signals on interphase nuclei obtained from parental forms and a triticale hybrid (genomic formula AABBBRR), in which the maternal form is wheat and secalotriticum hybrids (genomic formula RRAABBB) in which the maternal form is rye. For measurements, we selected the largest spherical nuclei with large nucleoli in the late G2 phase, in which most of the loading of CENH3 into centromeric chromatin takes place.</p><p><strong>Results: </strong>When processing the results of the measurement of centromere sizes in the hybrids, the obtained values were compared with those expected for the case of no change in centromere sizes in any of the parental sets of chromosomes. We found no significant differences between expected and measured values.</p><p><strong>Conclusion: </strong>We believe that, in the case of allopolyploid hybrids between wheat and rye, centromeres of chromosomes from the parental species retain the sizes formed during evolution. This conservatism may be promoted by the high similarity in the structure of the CENH3 molecules between these species.</p>","PeriodicalId":11206,"journal":{"name":"Cytogenetic and Genome Research","volume":" ","pages":"170-180"},"PeriodicalIF":1.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142364775","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Detailed Karyological Investigation of three Endemic Cobitis Linnaeus, 1758 Species (Teleostei, Cobitidae) in Anatolia, Türkiye.","authors":"Sevgi Unal Karakus, Muhammet Gaffaroğlu, Muradiye Karasu Ayata, Martin Knytl","doi":"10.1159/000542804","DOIUrl":"10.1159/000542804","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Introduction: &lt;/strong&gt;Comparative cytogenetics is a vital approach for diagnosing chromosome abnormalities and identifying species-specific patterns. In this study, chromosomal analysis of three Anatolian endemic Cobitis species was performed: Cobitis bilseli, C. fahireae, and C. turcica.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods: &lt;/strong&gt;Conventional cytogenetic techniques such as Giemsa staining, C-banding, and Ag-NOR staining were applied, followed by measurements of chromosome arm lengths including analysis of the measured data.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;The diploid chromosome number, 2n = 50, was determined for all three species. The karyotype formulas were as follows: four pairs of metacentric, 5 pairs of submetacentric, and 16 pairs of subtelo-telocentric chromosomes in C. bilseli; 11 pairs of metacentric, 7 pairs of submetacentric, and 7 pairs of subtelo-telocentric chromosomes in C. fahireae; and 4 pairs of metacentric, 4 pairs of submetacentric, and 17 pairs of subtelo-telocentric chromosomes in C. turcica. Dark C-bands were observed on the pericentromeres of nearly all chromosomes in C. bilseli and C. turcica, whereas light C-bands appeared on the pericentromeres of some chromosomes in C. fahireae. Silver-stained metaphases revealed signals on the short arm of a submetacentric chromosome pair in C. fahireae (each homologous chromosome carries one signal), while in C. bilseli and C. turcica, Ag-NOR signals were detected on the long arm of a single metacentric chromosome (only one homologous chromosome carries the signal, and the signal-carrying chromosome is the largest chromosome in the karyotype).&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusion: &lt;/strong&gt;This study provides new cytogenetic data consistent with the phylogenetic distances between the studied species, indicating that pericentric inversions and/or translocations govern the formation of Cobitis karyotypes.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Introduction: &lt;/strong&gt;Comparative cytogenetics is a vital approach for diagnosing chromosome abnormalities and identifying species-specific patterns. In this study, chromosomal analysis of three Anatolian endemic Cobitis species was performed: Cobitis bilseli, C. fahireae, and C. turcica.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods: &lt;/strong&gt;Conventional cytogenetic techniques such as Giemsa staining, C-banding, and Ag-NOR staining were applied, followed by measurements of chromosome arm lengths including analysis of the measured data.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;The diploid chromosome number, 2n = 50, was determined for all three species. The karyotype formulas were as follows: four pairs of metacentric, 5 pairs of submetacentric, and 16 pairs of subtelo-telocentric chromosomes in C. bilseli; 11 pairs of metacentric, 7 pairs of submetacentric, and 7 pairs of subtelo-telocentric chromosomes in C. fahireae; and 4 pairs of metacentric, 4 pairs of submetacentric, and 17 pairs of subtelo-telocentric chromosomes in C. turcica. Dark C-bands were observed on the pericentromeres of nearly all chromosomes ","PeriodicalId":11206,"journal":{"name":"Cytogenetic and Genome Research","volume":" ","pages":"243-256"},"PeriodicalIF":1.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11825084/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142767161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spaghetti Connections: Synaptonemal Complexes as a Tool to Explore Chromosome Structure, Evolution, and Meiotic Behavior in Fish.","authors":"Artem Lisachov, Dmitrij Dedukh, Sergey Simanovsky, Thitipong Panthum, Worapong Singchat, Kornsorn Srikulnath","doi":"10.1159/000538238","DOIUrl":"10.1159/000538238","url":null,"abstract":"<p><strong>Background: </strong>The synaptonemal complex (SC) is a protein axis formed along chromosomes during meiotic prophase to ensure proper pairing and crossing over. SC analysis has been widely used to study the chromosomes of mammals and less frequently of birds, reptiles, and fish. It is a promising method to investigate the evolution of fish genomes and chromosomes as a part of complex approach.</p><p><strong>Summary: </strong>Compared with conventional metaphase chromosomes, pachytene chromosomes are less condensed and exhibit pairing between homologous chromosomes. These features of SCs facilitate the study of the small chromosomes that are typical in fish. Moreover, it allows the study of heteromorphisms in sex chromosomes and supernumerary chromosomes. In addition, it enables the investigation of the pairing between orthologous chromosomes in hybrids, which is crucial for uncovering the causes of hybrid sterility and asexual reproduction, such as gynogenesis or hybridogenesis. However, the application of SC analysis to fish chromosomes is limited by the associated complications. First, in most fish, meiosis does not occur during every season and life stage. Second, different SC preparation methods are optimal for different fish species. Third, commercial antibodies targeting meiotic proteins have been primarily developed against mammalian antigens, and not all of them are suitable for fish chromosomes.</p><p><strong>Key messages: </strong>In the present review, we provide an overview of the methods for preparing fish SCs and highlight important studies using SC analysis in fish. This study will be valuable for planning and designing research that applies SC analysis to fish cytogenetics and genomics.</p>","PeriodicalId":11206,"journal":{"name":"Cytogenetic and Genome Research","volume":" ","pages":"1-15"},"PeriodicalIF":1.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140058914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Association of Leukocyte Telomere Length and the Risk of Disease Severity and Metabolic Comorbidities in Arab Patients with Psoriasis.","authors":"Materah Salem Alwehaidah, Moiz Bakhiet","doi":"10.1159/000542323","DOIUrl":"10.1159/000542323","url":null,"abstract":"<p><strong>Introduction: </strong>Several studies have related shortened leukocyte telomere length (LTL) with age-related diseases and worse prognosis. Telomere length attrition has recently been associated with inflammatory diseases, including psoriasis (Ps). However, no study has demonstrated an association between LTL and the risk of disease severity and metabolic comorbidities in Arab patients with Ps.</p><p><strong>Methods: </strong>68 patients with Ps and 42 normal controls were included. LTL and oxidative damage were determined by quantitative (q) PCR. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using logistic regression. Statistical differences between the groups were determined using χ2 and t tests.</p><p><strong>Results: </strong>Patients with Ps had significantly shorter LTL (p = 0.032) and higher oxidative damage (p = 0.015) than those without Ps. Patients with moderate-to-severe index (p = 0.03) and metabolic comorbidity showed significantly shorter LTL (p = 0.003) compared to patients with mild index and without metabolic comorbidity, respectively. Patients with short LTL (≤0.9) were correlated with higher risk of moderate-to-severe conditions (OR = 6.98, 95% CI = 2.3-20.8, p = 0.001) and metabolic comorbidities (OR = 2.89, 95% CI = 1.02-8.2, p = 0.04).</p><p><strong>Conclusion: </strong>LTL shortening may be a consequence of increased oxidative damage and is related to the risk of severe Ps and metabolic comorbidities. Therefore, LTL may be a good candidate biomarker for predicting the risk of poor prognosis in patients with Ps.</p>","PeriodicalId":11206,"journal":{"name":"Cytogenetic and Genome Research","volume":" ","pages":"211-217"},"PeriodicalIF":1.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142521341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Whole-Genome Sequencing Reveals a Novel Pathogenic GRIN2B Variant in a Patient with Neurodevelopmental Disorder and an inv(6)(p24p11.2)pat.","authors":"Carlos Córdova-Fletes, Horacio Rivera, Ma Guadalupe Domínguez-Quezada, Thania Alejandra Aguayo-Orozco, Elvira Garza-González, Luis A Núñez-García, Francisco Miguel Mercado-Silvae, Mónica Alejandra Rosales-Reynoso, Patricio Barros-Núñez","doi":"10.1159/000539975","DOIUrl":"10.1159/000539975","url":null,"abstract":"<p><strong>Introduction: </strong>Neurodevelopmental disorders (NDDs) are diverse and can be explained by either genomic aberrations or single nucleotide variants. Most likely due to methodological approaches and/or disadvantages, the concurrence of both genetic events in a single patient has hardly been reported and even more rarely the pathogenic variant has been regarded as the cause of the phenotype when a chromosomal alteration is initially identified.</p><p><strong>Case presentation: </strong>Here, we describe a NDD patient with a 6p nonpathogenic paracentric inversion paternally transmitted and a de novo pathogenic variant in the GRIN2B gene. Molecular-cytogenetic studies characterized the familial 6p inversion and revealed a paternal 9q inversion not transmitted to the patient. Subsequent whole-genome sequencing in the patient-father dyad corroborated the previous findings, discarded inversions-related cryptic genomic rearrangements as causative of the patient's phenotype, and unveiled a novel heterozygous GRIN2B variant (p.(Ser570Pro)) only in the proband. In addition, Sanger sequencing ruled out such a variant in her mother and thereby confirmed its de novo origin. Due to predicted disturbances in the local secondary structure, this variant may alter the ion channel function of the M1 transmembrane domain. Other pathogenic variants in GRIN2B have been related to the autosomal dominant neurodevelopmental disorder MRD6 (intellectual developmental disorder, autosomal dominant 6, with or without seizures), which presents with a high variability ranging from mild intellectual disability (ID) without seizures to a more severe encephalopathy. In comparison, our patient's clinical manifestations include, among others, mild ID and brain anomalies previously documented in subjects with MRD6.</p><p><strong>Conclusion: </strong>Occasionally, gross chromosomal abnormalities can be coincidental findings rather than a prime cause of a clinical phenotype (even though they appear to be the causal agent). In brief, this case underscores the importance of comprehensive genomic analysis in unraveling the wide-ranging genetic causes of NDDs and may bring new insights into the MRD6 variability.</p>","PeriodicalId":11206,"journal":{"name":"Cytogenetic and Genome Research","volume":" ","pages":"92-102"},"PeriodicalIF":1.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141455834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Novel 10q21.1-q22.1 Duplication in a Boy with Minor Facial Dysmorphism, Mild Intellectual Disability, Autism Spectrum Disorder-Like Phenotype, and Short Stature.","authors":"Jaime Toral-López, Luz María González-Huerta","doi":"10.1159/000541562","DOIUrl":"10.1159/000541562","url":null,"abstract":"<p><strong>Introduction: </strong>Duplications reported in 10q21-q22 include borderline to moderate intellectual disability, growth retardation, autism, attention deficit hyperactivity disorder, and minor craniofacial dysmorphism.</p><p><strong>Case presentation: </strong>We present a patient with a novel 14.7-Mb de novo interstitial duplication at 10q21.1-q22.1 delineated by a high-definition (HD) single nucleotide polymorphism (SNP) array. The boy had minor facial dysmorphism, mild intellectual disability, an autism spectrum disorder-like phenotype, and short stature.</p><p><strong>Conclusion: </strong>This is the first case in which a novel 10q21.1-q22.1 duplication was detected by the HD SNP array, expanding the spectrum of duplications seen in 10q21-q22. This report provides a detailed clinical examination of a patient with a 10q21.1-q22.1 duplication and suggests that brain development and cognitive function may be affected by an increased dosage sensitivity of the involved JMJD1C and EGR2 genes. This case contributes to the understanding of the genotype-phenotype relationship for genetic counseling and provides further evidence for the identification of a novel microduplication syndrome in 10q21-q22.</p>","PeriodicalId":11206,"journal":{"name":"Cytogenetic and Genome Research","volume":" ","pages":"148-153"},"PeriodicalIF":1.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142281876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Karyotypes and Chromosomal Mapping of Some Repetitive DNAs in Two Stingless Bee Species (Apidae: Meliponini), with the Description of a B Chromosome in Plebeia Genus.","authors":"Bárbara L F Andrade, Ana Luiza G Lopes, Gisele A Teixeira, Mara G Tavares","doi":"10.1159/000542295","DOIUrl":"10.1159/000542295","url":null,"abstract":"<p><strong>Introduction: </strong>Cytogenetic studies on stingless bees have significantly contributed to our understanding of karyotypic evolution and the composition of euchromatin and heterochromatin regions, including repetitive sequences.</p><p><strong>Methods: </strong>In this study, we performed classical cytogenetics, chromosomal banding, and mapping of some repetitive sequences in two stingless bee species, Frieseomelitta trichocerata and Plebeia poecilochroa.</p><p><strong>Results: </strong>The species exhibit the typical diploid chromosome number of each genera, 2n = 30 for Frieseomelitta and 2n = 34 for Plebeia. Additionally, some individuals of P. poecilochroa presented a small heterochromatic B chromosome, showing a numeric variation of n = 17-18 in males and 2n = 34-35 in females. In both species, heterochromatin is primarily distributed in the short arm and centromeric regions. Centromeric regions were found to be AT-rich in both species, while subterminal/terminal regions of the short arms of one and six chromosomes presented GC-rich sites in P. poecilochroa and F. trichocerata, respectively. The rDNA clusters were mapped on two chromosomes in F. trichocerata, and in only one chromosome pair in P. poecilochroa. Microsatellites (GA)n, (GAG)n, and (CAA)n were predominantly mapped in euchromatic regions, while the telomeric motif (TTAGG)n mapped to the ends of most chromosomes, including the B chromosome of P. poecilochroa. The other repetitive probes used, including the rDNA clusters, do not label the B chromosome of P. poecilochroa.</p><p><strong>Conclusions: </strong>Our cytogenetic data highlight both similarities and differences when compared to other congeneric species, expanding the chromosomal data for both genera.</p>","PeriodicalId":11206,"journal":{"name":"Cytogenetic and Genome Research","volume":" ","pages":"267-275"},"PeriodicalIF":1.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142521343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}