Multicolor-FISH Characterization of a Prenatal Mosaicism for a Chromosomal Rearrangement Undetected by Molecular Cytogenetics
We present here a case of fetal mosaicism for a chromosomal rearrangement explored in amniocytes and fetal muscle, consisting of a major cell population (95%) with partial monosomy 4q and a minor population (5%) with additional material replacing the 4qter deleted segment. Molecular techniques (MLPA, array-CGH) failed to assess the origin of this material. Only multicolor-FISH identified the additional segment on chromosome 4 as derived from chromosome 17. Due to the poor prognosis, the couple chose to terminate the pregnancy. Because of low-level mosaicism, chromosomal microarray analysis (CMA), now considered as first-ti...
Source: Cytogenetic and Genome Research - April 7, 2021 Category: Genetics & Stem Cells Source Type: research
Chromosome Mapping of U2 snDNA in Species of < b > < i > Leptodactylus < /i > < /b > (Anura, Leptodactylidae)
Small nuclear RNA (snRNA) is a class of molecules involved in the processing of pre-mRNA and in regulatory cell processes. snRNAs are always associated with a set of specific proteins. The complexes are referred to as small nuclear ribonucleoproteins, and spliceosome U RNAs are their most common snRNA components. The repetitive sequences of U snDNAs have been cytogenetically mapped in several species of Arthropoda, fishes, and mammals; however, their distribution remains unknown in amphibians. Here, we show results of FISH mapping of U2 snDNA repetitive sequences in species of the amphibian genusLeptodactylus to reveal the...
Source: Cytogenetic and Genome Research - April 6, 2021 Category: Genetics & Stem Cells Source Type: research
Application of Copy Number Variation Sequencing in Genetic Analysis of Miscarriages in Early and Middle Pregnancy
This study identifies chromosomal abnormalities in aborted embryos/fetuses in early and middle pregnancy and explores the application value of CNV-seq in determining the causes of pregnancy termination. High-throughput sequencing was used to detect chromosome copy number variations (CNVs) in 116 aborted embryos in early and middle pregnancy. The detection data were compared with the Database of Genomic Variants (DGV), the Database of Chromosomal Imbalance and Phenotype in Humans using Ensemble Resources (DECIPHER), and the Online Mendelian Inheritance in Man (OMIM) database to determine the CNV type and the clinical signif...
Source: Cytogenetic and Genome Research - March 23, 2021 Category: Genetics & Stem Cells Source Type: research
First Record of a B Chromosome in < b > < i > Polybia fastidiosuscula < /i > < /b > Saussure (Vespidae) and Investigation of Chromatin Composition Through Microsatellite Mapping
The characterization of karyotypes is an important aspect in understanding the structure and evolution of genomes.Polybia is a genus of social wasps of the family Vespidae. This genus has 58 species, but for only 8 of these chromosome number and morphology have been reported in the literature. The aim of this study was to describe and characterize thePolybia fastidiosuscula Saussure karyotype, presenting the first case of a B chromosome in Vespidae. In addition, we investigated the chromatin composition of this species through C-banding, base-specific fluorochrome staining, and physical mapping of 7 microsatellites and 18S...
Source: Cytogenetic and Genome Research - March 22, 2021 Category: Genetics & Stem Cells Source Type: research
Cytogenetic Analysis of < b > < i > Panaqolus tankei < /i > < /b > Cramer & amp; Sousa, 2016 (Siluriformes, Loricariidae), an Ornamental Fish Endemic to Xingu River, Brazil
Despite conservation of the diploid number, a huge diversity in karyotype formulae is found in the Ancistrini tribe (Loricariidae, Hypostominae). However, the lack of cytogenetic data for many groups impairs a comprehensive understanding of the chromosomal relationships and the impact of chromosomal changes on their evolutionary history. Here, we present for the first time the karyotype ofPanaqolus tankei Cramer amp; Sousa, 2016. We focused on the chromosomal characterization, using conventional and molecular cytogenetic techniques to unravel the evolutionary trends of this tribe.P. tankei, as most species of its sister gr...
Source: Cytogenetic and Genome Research - March 19, 2021 Category: Genetics & Stem Cells Source Type: research
Evolution of Sex Chromosome Heteromorphy in Geographic Populations of the Japanese Tago ’s Brown Frog Complex
The sex chromosomes of most anuran amphibians are characterized by homomorphy in both sexes, and evolution to heteromorphy rarely occurs at the species or geographic population level. Here, we report sex chromosome heteromorphy in geographic populations of the Japanese Tago ’s brown frog complex (2n = 26), comprisingRana sakuraii andR. tagoi. The sex chromosomes ofR. sakuraii from the populations in western Japan were homomorphic in both sexes, whereas chromosome 7 from the populations in eastern Japan were heteromorphic in males. Chromosome 7 ofR. tagoi, which is distributed close toR. sakuraii in eastern Japan, was hig...
Source: Cytogenetic and Genome Research - March 18, 2021 Category: Genetics & Stem Cells Source Type: research
Homogeneously Staining Regions (HSR) in Chromosome 1 of the House Mouse: Synapsis and Recombination at Meiosis
Amplified sequences constitute a large part of mammalian genomes. A chromosome 1 containing 2 large (up to 50 Mb) homogeneously staining regions (HSRs) separated by a small inverted euchromatic region is present in many natural populations of the house mouse (Mus musculus musculus). The HSRs are composed of a long-range repeat cluster,Sp100-rs, with a repeat length of 100 kb. In order to understand the organization and function of HSRs in meiotic chromosomes, we examined synapsis and recombination in male mice hetero- and homozygous for the HSR-carrying chromosome using FISH with an HSR-specific DNA probe and immunolocaliz...
Source: Cytogenetic and Genome Research - March 16, 2021 Category: Genetics & Stem Cells Source Type: research
Evolution of Tandemly Arranged Repetitive DNAs in Three Species of Cyprinoidei with Different Ploidy Levels
Polyploid species represent a challenge for both cytogenetic and genomic studies due to their high chromosome numbers and the morphological similarity between their paralogous chromosomes. This paper describes the use of low-coverage high-throughput sequencing to identify the 14 most abundant tandemly arranged repetitive elements in the paleotetraploid genome of the crucian carp (Carassius carassius, 2n = 100). These repetitive elements were then used for molecular cytogenetic studies of a closely related functionally triploid form of the Prussian carp (Carassius gibelio, 3n = 150 + Bs) and a relatively distant diploid spe...
Source: Cytogenetic and Genome Research - March 5, 2021 Category: Genetics & Stem Cells Source Type: research
Analysis of Copy Number Variations by Low-Depth Whole-Genome Sequencing in Fetuses with Congenital Cardiovascular Malformations
In this study, 181 fetuses were screened by fetal echocardiography for prenatal diagnosis of congenital heart disease, including 146 cases without ultrasound extracardiac findings (Group A) and 35 cases with ultrasound extracardiac findings (Group B). All cases were analyzed by clinical data, karyotyping, and low-depth whole-genome sequencing. The rates of chromosomal abnormalities in Groups A and B were 4.8% (7/146) and 37.1% (13/35), respectively. There was a significant difference in the incidence of chromosomal abnormalities between Groups A and B (p #x3c; 0.001). In Group A, CNV-seq identified copy number variations (...
Source: Cytogenetic and Genome Research - March 1, 2021 Category: Genetics & Stem Cells Source Type: research
Knockout of Ajuba Attenuates the Growth and Migration of Hepatocellular Carcinoma Cells
In conclusion, these results indicate that Ajuba is upregulated in HCC and promotes cell growth and migration of HCC cells, suggesting that Ajuba could possibly be a new target for HCC diagnosis and treatment.Cytogenet Genome Res (Source: Cytogenetic and Genome Research)
Source: Cytogenetic and Genome Research - February 26, 2021 Category: Genetics & Stem Cells Source Type: research
The Effectiveness of Next-Generation Sequencing-Based Preimplantation Genetic Testing for Balanced Translocation Couples
The purpose of this study was to evaluate the effectiveness of next-generation sequencing (NGS)-based preimplantation genetic testing (PGT) for balanced translocation carriers to identify normal/balanced blastocysts and to measure pregnancy outcomes following euploid embryo transfer. We enrolled 75 couples with a balanced translocation who underwent 83 PGT cycles (58 cycles for carriers with reciprocal translocations and 25 cycles for carriers with Robertsonian translocations) and 388 blastocysts were diagnosed. Moreover, we transferred single euploid blastocysts through frozen embryo transfer and calculated the biochemica...
Source: Cytogenetic and Genome Research - February 25, 2021 Category: Genetics & Stem Cells Source Type: research
Tandem Repeat-Based Probes Support the Loop Model of Pericentromere Packing
In this study, we used a set of TR in the genomes of the pig (Sus scrofa) and the Chinese hamster (Cricetulus griseus) identified with the help of bioinformatics techniques and determined the specificity of the designed probes. The signal of the 4 pig TR probes in spermatogenic cells was often ring-shaped, especially in primary spermatocytes. The rings were located in the regions relatively weakly stained with DAPI. The unique assembly of the centromeric region was traced using the hamster meiotic chromosomes. The probe specific to chromosome 5 was used. Two signals, arranged as rings, were seen at the pachytene stage, sim...
Source: Cytogenetic and Genome Research - February 18, 2021 Category: Genetics & Stem Cells Source Type: research
A New Variant B Chromosome in Auchenipteridae: The Role of (GATA) < sub > n < /sub > and (TTAGGG) < sub > n < /sub > Sequences in Understanding the Evolution of Supernumeraries in < b > < i > Trachelyopterus < /i > < /b >
This study aimed to describe and understand the structure and evolution ofTrachelyopterus B chromosomes, mainly through physical mapping of repetitive elements. A diploid number of 58 chromosomes was found for all individuals, as well as the presence of B chromosomes. ForT. porosus this is the first report of a supernumerary. The sympatric species ofT. galeatus andT. porosus from Amazon River had 1 –3 B chromosomes andT. galeatus from Paraguay River had 1 –2 B chromosomes, all of them showed intra- and interindividual numerical variation. Two females ofT. porosus exhibited a new variant B chromosome (B2), previously no...
Source: Cytogenetic and Genome Research - February 18, 2021 Category: Genetics & Stem Cells Source Type: research
Molecular Cytogenetic Characterization of the Murine Melanoma Cell Lines S91 Clone M3 and B16-F1 with Variant B16-4A5
This study revealed severely rearranged karyotypes with in parts similar imbalances for all 3 cell lines. Interestingly, they involve genes known to play major roles in human melanoma. These are specifically the oncogenes and tumor suppressor genes, being associated with aggressive forms of melanoma. B16-F1, B16-4A5, and S91 clone M3 revealed aberrations which were similarly observed in human eye and skin but not in human uveal melanoma. Thus, they can be considered as model systems for advanced eye and skin melanoma.Cytogenet Genome Res (Source: Cytogenetic and Genome Research)
Source: Cytogenetic and Genome Research - February 17, 2021 Category: Genetics & Stem Cells Source Type: research
SINE-B1 Distribution and Chromosome Rearrangements in the South American < b > < i > Proechimys < /i > < /b > gr. < b > < i > goeldii < /i > < /b > (Echimyidae, Rodentia)
Proechimys species are remarkable for their extensive chromosome rearrangements, representing a good model to understand genome evolution. Herein, we cytogenetically analyzed 3 different cytotypes ofProechimys gr.goeldii to assess their evolutionary relationship. We also mapped the transposable element SINE-B1 on the chromosomes ofP. gr.goeldii in order to investigate its distribution among individuals and evaluate its possible contribution to karyotype remodeling in this species. SINE-B1 showed a dispersed distribution along chromosome arms and was also detected at the pericentromeric regions of some chromosomes, includin...
Source: Cytogenetic and Genome Research - February 8, 2021 Category: Genetics & Stem Cells Source Type: research
