Large terminal fragments of human chromosomes 2p, 6p, 8q, 12q, and 18q were cloned using yeast artificial chromosomes (YACs). RecA-assisted restriction endonuclease (RARE) cleavage analysis of genomic DNA samples from II unrelated individuals using YAC-derived probes confirmed the telomeric localizations of the half-YACs studied. The cloned fragments provide telomeric closure of maps for the re...

In the first cytogenetic study of the recently proposed family Myerslopiidae the male karyotype of Mapucheachilensis (Nielson, 1996) was analyzed using conventional chromosome staining, AgNOR- and C-bandings, and fluorescence in situ hybridization (FISH) with 18S rDNA and (TTAGG) n telomeric probes. A karyotype of 2n = 16 + XY, NOR on a medium-sized pair of autosomes, subterminal location of C-...

Human telomeres play a major role in stabilizing chromosome ends and preventing fusions. Chromosomes bearing a broken end are rescued by the acquisition of a new telomeric cap without any subtelomeric sequences being present at the breakpoint, a process referred to as chromosome healing. Conversely, a loss of telomeric function or integrity can lead to the presence of interstitial telomeres at ...

Buteoninae (Falconiformes, Accipitridae) consist of the widely distributed genus Buteo, and several closely related species in a group called "sub-buteonine hawks", such as Buteogallus, Parabuteo, Asturina, Leucopternis and Busarellus, with unsolved phylogenetic relationships. Diploid number ranges between 2n = 66 and 2n = 68. Only one species, L. albicollis had its karyotype analyzed by molecu...

This report describes the intranuclear organization of chromosomes in human-hamster hybrid nuclei and in human cell nuclei. The target chromosomes were stained using in situ hybridization with biotinylated, chromosome-specific DNA probes. Bound probe was detected with fluorescein-avidin. Hybridizations were performed to fixed nuclei in aqueous suspension in order to preserve their three-dimensi...

The HLA class I genes are located within a 2-million-base pair (2-Mbp) region constituting the telomeric half of the human major histocompatibility complex. The large majority of the class I sequences, including the HLA-A, -E, -F, and -G genes, is found within the telomeric 1 Mbp. We report here the isolation and characterization of yeast artificial chromosome (YAC) clones that span a contiguou...

Forty Theileria schizont-infected lymphocyte culture isolates from Zimbabwe were characterized using a panel of antischizont monoclonal antibodies (MAbs) and 4 Theileria parva DNA probes containing cloned extrachromosomal element, Tpr repetitive, ribosomal and telomeric sequences. The Theileria isolates were assigned as T. parva or T. taurotragi on the basis of reactivities with MAbs and restri...

The frequency of dicentric chromosomes in human peripheral blood lymphocytes at metaphase is considered as the "gold-standard" method for biological dosimetry and, presently, it is the most widely used for dose assessment. Yet, it needs lymphocyte stimulation and a 2-day culture, failing the requirement of rapid dose estimation, which is a high priority in radiation emergency medicine and triag...

Although mechanisms for chromosomal instability in tumors have been described in animal and in vitro models, little is known about these processes in man. To explore cytogenetic evolution in human tumors, chromosomal breakpoint profiles were constructed for 102 pancreatic carcinomas and 140 osteosarcomas, two tumor types characterized by extensive genomic instability. Cases with few chromosomal...

A series of dye-labeled oligonucleotide probes containing base and sugar modifications were tested for the ability to detect telomeric repeat sequences in FISH assays. These modified oligonucleotides, all 18 nt in length, were complementary to either the cytidine-rich (C(3)TA(2))(n)or guanosine-rich (T(2)AG(3))(n)telomere target sequences. Oligonucleotides were modified to either increase targe...