Search results for "Chromosome painting"

Genetic aspects in hominid evolution

2000

Genomic comparison between apes and humans have made important contributions to our understanding of human evolution. The modern period of karyological comparisons between humans and other primates began about forty years ago and has been marked by a series of technical revolutions. In the 1960s pioneering genetic and chromosomal comparisons of human and great apes suggested, as had Darwin a century before, that our closest relative were the African apes. Early immunological analyses placed human/apes divergence at about five million year ago. Acceptance of man’s late divergence from the African apes was delayed by the scarcity of paleontological evidence coupled with a fallacious Asiatic o…

Reconstructing the Phylogeny of the Human Chromosome 4 Synteny using Comparative Karyology and Genomic Data Analysis

2010

Abstract This work focuses on the evolution of the architecture of human chromosome 4 (HSA4) through the analysis of chromosomal regions that have been conserved over time, and the comparison of regions that have been involved in different rearrangements in placental lineages. As with most elements of the human genome, HSA4 is considered to be evolutionarily stable. A more detailed analysis indicates that the syntenic association has been reshuffled by a series of rearrangements, yielding different chromosomes in various taxa. In its ancestral eutherian state, HSA4 has a syntenic association with HSA8p. We investigated the complex origin of this human chromosome using three different approa…

Phylogenomics of species from four genera of New World monkeys by flow sorting and reciprocal chromosome painting

2007

Abstract Background The taxonomic and phylogenetic relationships of New World monkeys (Platyrrhini) are difficult to distinguish on the basis of morphology and because diagnostic fossils are rare. Recently, molecular data have led to a radical revision of the traditional taxonomy and phylogeny of these primates. Here we examine new hypotheses of platyrrhine evolutionary relationships by reciprocal chromosome painting after chromosome flow sorting of species belonging to four genera of platyrrhines included in the Cebidae family: Callithrix argentata (silvered-marmoset), Cebuella pygmaea (pygmy marmoset), Callimico goeldii (Goeldi's marmoset) and Saimiri sciureus (squirrel monkey). This is t…

Studio sull’origine e l’evoluzione del cromosoma 4 dell’uomo mediante la citogenetica molecolare comparata

2011

Diffuse Type of Giant-Cell Tumor of Tendon Sheath: An Ultrastructural Study of Two Cases With Cytogenetic Support

2002

Two cases of the diffuse type of giant-cell tumor of the tendon sheath (GCTTS) are described. Both tumors arose in the vicinity of large joints of the lower extremity, showing similar clinical and radiological features. Histologically, a proliferation of polygonal mononuclear cells was seen, together with osteoclastlike giant cells, foam cells, and siderophages. The tumors were poorly delineated, displaying an infiltrative pattern into the neighboring soft tissues. Immunohistochemically, strong expression of vimentin, neuron-specific enolase, A1-antitrypsin, and CD68 was found in both mono- and multinucleated tumor cells. At the ultrastructural level, mononuclear cells revealed a diverse mo…

Sex reversal from functional disomy of Xp: Prenatal and post-mortem findings.

2008

Translocations involving the short arms of the X and Y chromosomes are uncommon and are often associated with anomalies in gonadal development. Segmental duplications of the X chromosome interfere with the formation of the testis in patients with a 46,XY karyotype. The gene products located within the duplicated segment, when present in double dose, may affect on male sex development. We report on a fetus with karyotype 46,XY,der (14)t(X;14) (p10;p10)dn. Attached to chromosome 14 is the entire short arm of the X chromosome. Therefore, the fetus is affected with a disomy of Xp, resulting in complete male to female sex reversal, as well as other structural defects. To the best of our knowledg…

Chromosome painting for cytogenetic monitoring of occupationally exposed and non-exposed groups of human individuals.

2001

The suitability of a three-color fluorescence in situ suppression hybridization technique was examined for monitoring five different groups of individuals: 30 occupied in radiology, 26 occupied in nuclear medicine or radiation physics, 32 patients with breast cancer, 26 occupied with military waste disposal, all presumably exposed to low doses of radiation or chemical mutagens and a non-exposed control group (N=29). The average frequency of breaks constituting the various aberrations did not significantly differ between the groups of medical radiation appliers and the control group. However, breast tumor patients and military waste disposers, as groups, showed a higher aberration rate than …

Mapping genomic rearrangements in titi monkeys by chromosome flow sorting and multidirectional in-situ hybridization.

2004

We developed chromosome painting probes for Callicebus pallescens from flow-sorted chromosomes and used multidirectional chromosome painting to investigate the genomic rearrangements in C. cupreus and C. pallescens. Multidirectional painting provides information about chromosomal homologies at the subchromosomal level and rearrangement break points, allowing chromosomes to be used as cladistic markers. Chromosome paints of C. pallescens were hybridized to human metaphases and 43 signals were detected. Then, both human and C. pallescens probes were hybridized to the chromosomes of another titi monkey, C. cupreus. The human chromosome paints detected 45 segments in the haploid karyotype of C.…

Complete karyotype characterization of the K562 cell line by combined application of G-banding, multiplex-fluorescence in situ hybridization, fluores…

2001

This study combines conventional cytogenetics, fluorescence in situ hybridization (FISH), multiplex-FISH and comparative genomic hybridization (CGH). In applying this multimodal approach on the human leukemia cell line K562, the chromosome composition was refined in detail and compared with data from the literature. A hypotriploid karyotype with a modal chromosome number of 67, and 21 unique marker chromosomes were identified. The classification of six markers was identical to published data and the composition of five further markers from the literature could be fully clarified for the first time. The composition of another five markers, which have been interpreted in divergent ways in dif…

Eight million years of maintained heterozygosity in chromosome homologs of cercopithecine monkeys

2020

In the Cercopithecini ancestor two chromosomes, homologous to human chromosomes 20 and 21, fused to form the Cercopithecini specific 20/21 association. In some individuals from the genus Cercopithecus, this association was shown to be polymorphic for the position of the centromere, suggesting centromere repositioning events. We set out to test this hypothesis by defining the evolutionary history of the 20/21 association in four Cercopithecini species from three different genera. The marker order of the various 20/21 associations was established using molecular cytogenetic techniques, including an array of more than 100 BACs. We discovered that five different forms of the 20/21 association w…