145 research outputs found

    Homologies in human and Macasa fuscata chromosomes revealed by in situ suppression hybridization with human chromosome specific DNA libraries

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    We established chromosomal homologies between all chromosomes of the human karyotype and that of an old world monkey (Macaca fuscata) by chromosomal in situ suppression (CISS) hybridization with human chromosome specific DNA libraries. Except for the human chromosome 2 library and limited cross-hybridization of X and Y chromosome libraries all human DNA libraries hybridized to single GTG-banded macaque chromosomes. Only three macaque chromosomes (2, 7, 13) were each hybridized by two separate human libraries (7 and 21, 14 and 15, 20 and 22 respectively). Thus, an unequivocally high degree of synteny between human and macaque chromosomes has been maintained for more than 20 million years. As previously suggested, both Papionini (macaques, baboons, mandrills and cercocebus monkeys, all of which have nearly identical karyotypes) and humans are chromosomally conservative. The results suggest, that CISS hybridization can be expected to become an indispensable tool in comparative chromosome and gene mapping and will help clarify chromosomal phylogenies with speed and accuracy

    Timing the first human migration into eastern Asia

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    A recent report in BMC Biology indicates that modern humans first arrived in southern East Asia 60,000 years ago and settled the rest of East Asia from there. This early date and migration route has significant implications for our understanding of the origins of present-day human populations

    Molecular and classical cytogenetic analyses demonstrate an apomorphic reciprocal chromosomal translocation in Gorilla gorilla

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    The existence of an apomorphic reciprocal chromosomal translocation in the gorilla lineage has been asserted or denied by various cytogeneticists. We employed a new molecular cytogenetic strategy (chromosomal in situ suppression hybridization) combined with high-resolution banding, replication sequence analysis, and fluorochrome staining to demonstrate that a reciprocal translocation between ancestral chromosomes homologous to human chromosome 5 and 17 has indeed occurred

    Evolution of mammalian genome organization inferred from comparative gene mapping.

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    The genome diversity and karyotype evolution of mammals

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    The past decade has witnessed an explosion of genome sequencing and mapping in evolutionary diverse species. While full genome sequencing of mammals is rapidly progressing, the ability to assemble and align orthologous whole chromosome regions from more than a few species is still not possible. The intense focus on building of comparative maps for companion (dog and cat), laboratory (mice and rat) and agricultural (cattle, pig, and horse) animals has traditionally been used as a means to understand the underlying basis of disease-related or economically important phenotypes. However, these maps also provide an unprecedented opportunity to use multispecies analysis as a tool for inferring karyotype evolution. Comparative chromosome painting and related techniques are now considered to be the most powerful approaches in comparative genome studies. Homologies can be identified with high accuracy using molecularly defined DNA probes for fluorescence in situ hybridization (FISH) on chromosomes of different species. Chromosome painting data are now available for members of nearly all mammalian orders. In most orders, there are species with rates of chromosome evolution that can be considered as 'default' rates. The number of rearrangements that have become fixed in evolutionary history seems comparatively low, bearing in mind the 180 million years of the mammalian radiation. Comparative chromosome maps record the history of karyotype changes that have occurred during evolution. The aim of this review is to provide an overview of these recent advances in our endeavor to decipher the karyotype evolution of mammals by integrating the published results together with some of our latest unpublished results

    The Ancestral Eutherian Karyotype Is Present in Xenarthra

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    Molecular studies have led recently to the proposal of a new super-ordinal arrangement of the 18 extant Eutherian orders. From the four proposed super-orders, Afrotheria and Xenarthra were considered the most basal. Chromosome-painting studies with human probes in these two mammalian groups are thus key in the quest to establish the ancestral Eutherian karyotype. Although a reasonable amount of chromosome-painting data with human probes have already been obtained for Afrotheria, no Xenarthra species has been thoroughly analyzed with this approach. We hybridized human chromosome probes to metaphases of species (Dasypus novemcinctus, Tamandua tetradactyla, and Choloepus hoffmanii) representing three of the four Xenarthra families. Our data allowed us to review the current hypotheses for the ancestral Eutherian karyotype, which range from 2n = 44 to 2n = 48. One of the species studied, the two-toed sloth C. hoffmanii (2n = 50), showed a chromosome complement strikingly similar to the proposed 2n = 48 ancestral Eutherian karyotype, strongly reinforcing it

    Evolution of mammalian genome organization inferred from comparative gene mapping

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    Comparative genome analyses, including chromosome painting in over 40 diverse mammalian species, ordered gene maps from several representatives of different mammalian and vertebrate orders, and large-scale sequencing of the human and mouse genomes are beginning to provide insight into the rates and patterns of chromosomal evolution on a whole-genome scale, as well as into the forces that have sculpted the genomes of extant mammalian species

    A standardized G‐banded karyotype for the raccoon (Procyon lotor) compared with the domestic cat

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    We propose a standardized karyotype for the raccoon (Procyon lotor; 2n = 38, FN 74) and compare it with that of the domestic cat (2n = 38, FN 72). Numerous chromosomes (12) have similar and sometimes identical G-banding and 14 chromosome pairs have remained intact. Other chromosomes apparently differ by Robertsonian translocations and inversions. The conservation of these karyotypes is remarkable considering that the divergence of procyonids and felids predates 50 million years B.P. However, the common diploid number of 38 is not a primitive retention, as sometimes hypothesized. Instead, cats and raccoons converged on this chromosome number by a different series of translocations. The unsolved problems of carnivore phylogeny could benefit from a combination of high resolution banding and molecular cytogenetic analyses

    Il Museo di Storia Naturale dell'Università degli Studi di Firenze. Le collezioni antropologiche ed etnologiche / The Museum of Natural History of the University of Florence. The Anthropological and Ethnological Collections

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    This volume is dedicated to the Anthropological and Ethnological section of the Natural History Museum. First the historical journey of the collections is traced from the antique nucleus of the Medici to the foundation of the National Museum of Anthropology and Ethnology, when Florence was the capitol of Italy, and the discipline of anthropology was born. The second part illustrates the multivariate collections from all over the globe. They are a precious record of the past and present biological and cultural diversity of our species opening wide horizons that rigorously connect science to the many faces of human culture, including art. The third section is dedicated to current research and opens new prospectives on the significance of ethnological and anthropological collections due to new technology and in light of a new appreciation of the museum as a living “zone of contact”

    Il Museo di Storia Naturale dell'Università degli Studi di Firenze. Le collezioni antropologiche ed etnologiche / The Museum of Natural History of the University of Florence. The Anthropological and Ethnological Collections

    Get PDF
    This volume is dedicated to the Anthropological and Ethnological section of the Natural History Museum. First the historical journey of the collections is traced from the antique nucleus of the Medici to the foundation of the National Museum of Anthropology and Ethnology, when Florence was the capitol of Italy, and the discipline of anthropology was born. The second part illustrates the multivariate collections from all over the globe. They are a precious record of the past and present biological and cultural diversity of our species opening wide horizons that rigorously connect science to the many faces of human culture, including art. The third section is dedicated to current research and opens new prospectives on the significance of ethnological and anthropological collections due to new technology and in light of a new appreciation of the museum as a living “zone of contact”
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