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T Ried

Publications and source records attributed to T Ried.

126 records · Page 7Linked to original sources

Comparative high-resolution mapping of human and primate chromosomes by fluorescence in situ hybridization.

A molecular cytogenetic approach that facilitates high-resolution comparative mapping of defined human genes in different primate species is presented. Fluorescence in situ hybridization and digital imaging microscopy were used to visualize human DNA probes on simultaneously banded or "painted" metaphase chromosomes of great apes (Pan troglodytes, Gorilla gorilla, Pongo pygmaeus), hylobatids (Hylobates lar and Hylobates syndactylus), and Old World monkeys (Macaca fuscata and Cercopithecus aethiops). Using a series of DNA probes, chromosomal rearrangements in the karyotypes of primates were readily detected at the molecular cytogenetic level. This approach should contribute considerably to the understanding of primate phylogeny and evolution.

Animals↗

An alphoid DNA sequence conserved in all human and great ape chromosomes: evidence for ancient centromeric sequences at human chromosomal regions 2q21 and 9q13.

Using vector-CENP-B box polymerase chain reaction (PCR) we isolated and cloned from a human chromosome 21-specific plasmid library, a 1 kb DNA sequence, named p alpha H21. In in situ hybridization experiments, p alpha H21 hybridized, under high stringency conditions, to the centromeric region of all the human, chimpanzee, gorilla and orangutan chromosomes. On human chromosomes p alpha H21 also identified non-centromeric sequences at 2q21 (locus D2F33S1) and 9q13 (locus D9F33S2). The possible derivation of these sequences from ancestral centromeres is discussed. Sequence analysis confirmed the alphoid nature of the whole p alpha H21 insert.

Animals↗

Evaluation of the utility of interphase cytogenetics to detect residual cells with a malignant genotype in mixed cell populations: a Burkitt lymphoma model.

Interphase cytogenetics has been used to detect tumor cells in the presence of a large excess of normal cells. Probes for fluorescence in situ hybridization were chosen to reveal a specific hybridization pattern in tumor cell nuclei as well as to provide an internal control for the assessment of the hybridization results. By enumerating mixtures of cytogenetically normal cells and tumor cells from a Burkitt lymphoma cell line, we were able to detect tumor cells at a frequency of one in 500. Normal cells could be differentiated from Burkitt lymphoma cells with a specificity of approximately 99.9%.

Burkitt Lymphoma↗

Molecular cytogenetic analysis of formalin-fixed, paraffin-embedded solid tumors by comparative genomic hybridization after universal DNA-amplification.

We present a technique which allows the detection and chromosomal localization of DNA sequence copy number changes in solid tumor genomes from frozen sections and paraffin embedded, formalin fixed specimens. Based on comparative genomic hybridization and on universal DNA amplification procedures this technique is possible even if only a few tumor cells are available. We demonstrate the feasibility of this method to visualize complete and partial chromosome gains and losses and gene amplifications in archived solid tumor samples.

Base Sequence↗

Simultaneous visualization of seven different DNA probes by in situ hybridization using combinatorial fluorescence and digital imaging microscopy.

Combinatorial labeling of probes (i.e., with two or more different reporters) increases the number of target sequences that can be detected simultaneously by fluorescence in situ hybridization. We have used an epifluorescence microscope equipped with a digital imaging camera and computer software for pseudocoloring and merging images to distinguish up to seven different probes using only three fluorochromes. Chromosome-specific centromere repeat clones and chromosome-specific "composite" probe sets were generated by PCR in which different mixtures of modified nucleotides, including fluorescein-conjugated dUTP, were incorporated. Cosmid clones were labeled similarly by nick-translation. The technique has been used to delineate the centromeres of seven different human chromosomes, on both 4',6-diamidino-2-phenylindole-stained metaphase spreads and interphase nuclei, to map six cosmid clones in a single hybridization experiment and to detect chromosome translocations by chromosome painting. Multiparameter hybridization analysis should facilitate molecular cytogenetics, probe-based pathogen diagnosis, and gene mapping studies.

Centromere↗

Specific metaphase and interphase detection of the breakpoint region in 8q24 of Burkitt lymphoma cells by triple-color fluorescence in situ hybridization.

Triple fluorescence in situ hybridization with a plasmid DNA library from sorted human chromosomes 8 in combination with bacteriophage clones flanking the breakpoint in 8q24 of the Burkitt lymphoma cell line J1 was used for the specific delineation of this breakpoint in individual tumor cells. With this approach, tumor-specific breakpoints in translocation chromosomes can be detected at all stages of the cell cycle with high specificity.

Burkitt Lymphoma↗

Clustering of C2-H2 zinc finger motif sequences within telomeric and fragile site regions of human chromosomes.

Ninety-three phage clones identified by hybridization with a C2-H2 zinc finger sequence probe have been grouped into 23 genetic loci. Partial sequencing verified that each locus belonged to the zinc finger family. Oligonucleotide primer pairs were developed from these sequences to serve as STS markers for these loci. One or more clones from each locus was mapped onto human metaphase chromosomes by fluorescence in situ hybridization. Several loci map to identical chromosomal regions, indicating the possible presence of multigene clusters. Zinc finger loci were found to reside predominantly either in telomeric regions or in chromosomal bands known to exhibit chromosome fragility. Chromosome 19 carries a disproportionate fraction (10 of 23) of the mapped zinc finger loci.

Amino Acid Sequence↗

Multicolor fluorescence in situ hybridization for the simultaneous detection of probe sets for chromosomes 13, 18, 21, X and Y in uncultured amniotic fluid cells.

The most frequent aneuploidies in newborns involve the autosomes 13, 18 and 21 as well as both sex chromosomes. Fluorescence in situ hybridization readily allows the detection of numerical chromosomal aberrations throughout all stages of the cell cycle. Using a multicolor fluorescence in situ hybridization approach based on combinatorial probe labeling and digital imaging microscopy we demonstrate the simultaneous visualization of probe sets specific for chromosomes 13, 18, 21, X and Y. This approach enables one to evaluate aberrations of multiple chromosomes in a single hybridization experiment using metaphase chromosomes and interphase nuclei from a variety of cell types, including lymphocytes and amniocytes.

Amniotic Fluid↗

In situ hybridization with fluoresceinated DNA.

We have used fluorescein-11-dUTP in a nick-translation format to produce fluoresceinated human nucleic acid probes. After in situ hybridization of fluoresceinated DNAs to human metaphase chromosomes, the detection sensitivity was found to be 50-100 kb. The feasibility and the increase in detection sensitivity of microscopic imaging of in situ hybridized, fluoresceinated DNA with an integrating solid state camera for rapid cosmid mapping is illustrated. Combination of fluoresceinated DNA with biotinated and digoxigeninated DNAs allowed easy performance of triple fluorescence in situ hybridization. The potential of these techniques for DNA mapping, cytogenetics and biological dosimetry is briefly discussed.

DNA Probes↗

Cloning of a human cDNA expressing a high voltage-activating, TEA-sensitive, type-A K+ channel which maps to chromosome 1 band p21.

Over ten different mammalian genes related to the Drosophila Shaker gene (the Sh gene family) have been identified recently. These genes encode subunits of voltage-dependent K+ channels. The family consists of four subfamilies: ShI genes are homologues of Shaker; ShII, ShIII, and ShIV are homologues of three other Shaker-like genes in Drosophila, Shab, Shaw, and Shal, respectively. We report here the cloning of a human K+ channel ShIII cDNA (HKShIIIC) obtained from a brain stem cDNA library. HKShIIIC transcripts express an atypical voltage-dependent transient (A-type) K+ current in Xenopus oocytes. This current is activated by large membrane depolarizations and is extremely sensitive to the K+ channel blocker TEA unlike most A-type currents. The gene encoding HKShIIIC maps to chromosome 1p21.

Amino Acid Sequence↗

Direct carrier detection by in situ suppression hybridization with cosmid clones of the Duchenne/Becker muscular dystrophy locus.

A basic problem in genetic counseling of families with Duchenne/Becker muscular dystrophy (DMD/BMD) concerns the carrier status of female relatives of an affected male. In about 60% of these patients, deletions of one or more exons of the dystrophin gene can be identified. These deletions preferentially include exon 45, which can be detected by multiplex polymerase chain reaction (PCR) and Southern blot analysis of genomic cosmid clones that map to this critical region. As a new approach for definitive carrier detection, we have performed chromosomal in situ suppression (CISS) hybridization with these cosmid clones in female relatives of four unrelated patients. In normal females, most metaphases showed signals on both X chromosomes, whereas only one X chromosome was labeled in carriers. Our results demonstrate that CISS hybridization can define the carrier status in female relatives of DMD patients exhibiting a deletion in the dystrophin gene.

Blotting, Southern↗

Isolation and characterization of the complete human beta-myosin heavy chain gene.

The entire gene coding for the human beta-myosin heavy chain has been isolated from genomic EMBL3A phage libraries by chromosomal walking starting from clone gMHC-1, reported earlier (Appelhans and Vosberg 1983). gMHC-1 has been shown to carry coding information for the C-terminal two-thirds of beta-myosin heavy chain, which is expressed in cardiac muscle and in slow skeletal muscle fibers (Lichter et al. 1986). Three DNA clones were identified as overlapping with gMHC-1 by restriction mapping and DNA sequencing. They span a 30-kb region in the genome. About 22 kb extend from the initiation codon ATG to the poly(A) addition site. The clones include about 4 kb of 5' flanking sequences upstream of the promoter. Comparisons of beta- and alpha-myosin heavy chain sequences indicate that gene duplication of the cardiac myosin heavy chain isogenes preceded the mammalian species differentiation.

Animals↗

Tumor cytogenetics revisited: comparative genomic hybridization and spectral karyotyping.

Fluorescence in situ hybridization techniques allow the visualization and localization of DNA target sequences on the chromosomal and cellular level and have evolved as exceedingly valuable tools in basic chromosome research and cytogenetic diagnostics. Recent advances in molecular cytogenetic approaches, namely comparative genomic hybridization and spectral karyotyping, now allow tumor genomes to be surveyed for chromosomal aberrations in a single experiment and permit identification of tumor-specific chromosomal aberrations with unprecedented accuracy. Comparative genomic hybridization utilizes the hybridization of differentially labeled tumor and reference DNA to generate a map of DNA copy number changes in tumor genomes. Comparative genomic hybridization is an ideal tool for analyzing chromosomal imbalances in archived tumor material and for examining possible correlations between these findings and tumor phenotypes. Spectral karyotyping is based on the simultaneous hybridization of differentially labeled chromosome painting probes (24 in human), followed by spectral imaging that allows the unique display of all human (and other species) chromosomes in different colors. Spectral karyotyping greatly facilitates the characterization of numerical and structural chromosomal aberrations, therefore improving karyotype analysis considerably. We review these new molecular cytogenetic concepts, describe applications of comparative genomic hybridization and spectral karyotyping for the visualization of chromosomal aberrations as they relate to human malignancies and animal models thereof, and provide evidence that fluorescence in situ hybridization has developed as a robust and reliable technique which justifies its translation to cytogenetic diagnostics.

Animals↗

Spectral karyotyping, a 24-colour FISH technique for the identification of chromosomal rearrangements.

Spectral karyotyping (SKY) is a new fluorescence in situ hybridisation (FISH) technique that refers to the molecular cytogenetic analysis of metaphase preparations by means of spectral microscopy. For SKY of human metaphase chromosomes, 24 chromosome-specific painting probes are used in just one FISH experiment. The probes are labelled by degenerate oligonucleotide-primed PCR using three fluorochromes and two haptens. Each probe is differentially labelled with one, two, three or four fluorescent dyes, resulting in a unique spectral signature for every chromosome. After in situ hybridisation and immunodetection, a spectral image is acquired using a conventional fluorescence light microscope equipped with a custom-designed triple-bandpass filter and the SpectraCube, which is able to retrieve spectral information for every pixel in a digital CCD image. The 24-colour display and chromosome classification are based on the unique emission spectra of the chromosomes. Together with chromosome banding information from an inverted DAPI or a G-banded metaphase, a comprehensive overview of chromosomal aberrations is presented.

Color↗

Gain of chromosome 3q is an early and consistent genetic aberration in carcinomas of the vulva.

The aim was to determine whether specific gains of chromosome 3q and laminin-5gamma2-chain expression can improve early detection of invasive capacity in precancerous and squamous cell carcinoma of the vulva (VSCC). Six VSCC and three precancerous lesions were studied. Multicolor fluorescence in situ hybridization (FISH) probe sets were applied to nuclei suspensions prepared from archival material using the Hedley method. The probe panel consists of the centromers of chromosome 7, chromosome 3, and the TERC gene residing on the long arm of chromosome 3. Laminin-5gamma2-chain immunohistochemical analysis was performed on corresponding specimens and was expressed only in the VSCC. The genome-specific FISH analysis revealed 3q amplification in 43% of the nuclei analyzed for the VSCC and 22% of the nuclei for the precancerous lesions. Low-level 3q amplifications were found in precancerous lesions with an average fold increase of 1.15 for 3q. The invasive lesions showed higher average fold increases for 3q, averaging 1.32. Laminin-5gamma2-chain protein was expressed only in VSCC, whereas 3q gains were observed both in precancerous lesions and in VSCC, indicating that gain of chromosome 3q is an early and consistent event during carcinogenesis of VSCC.

Adult↗

Molecular cytogenetics and gene analysis: implications for oncology nurses.

Current advances in genetics have provided a better understanding of many diseases, including cancer, and will have an impact on oncology clinical practice in an unprecedented way. The molecular cytogenetic techniques of fluorescent in situ hybridization (FISH), comparative genomic hybridization (CGH), and spectral karyotyping (SKY) are providing tremendous insights into genetic information related to cancer by specifically illustrating chromosomal abnormalities that can occur in a patient's cancer cells. The application of these techniques allows for the development of molecular diagnostic tests may be applied to clinical material, which may help to improve the diagnosis and staging of a patient's tumor, particularly in small, premalignant lesions that often are equivocal and difficult to assess. An understanding of these genetic changes will provide a foundation of knowledge for oncology nurses that will lead to significantly improved detection methods, therapies, and disease prevention. As members of the healthcare team, oncology nurses must be knowledgeable about the rapid expansion of genetic information. Oncology nurses are in a unique position to translate this information to patients and their families and, ultimately, enhance comprehensive care through patient education and advocacy.

Cytogenetic Analysis↗