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We analyzed the meiotic behavior of the sex chromosomes of the bats Glossophaga soricina (XX/XY), Artibeus cinereus and Uroderma magnirostrum (neo-XX/XY) using multicolor FISH. The X chromosome and pair 15 autosome probes are from Phyllostomus hastatus and the Y from Carollia brevicauda. On both species with the neo-XX/XY system, the autosome translocated to the sex chromosomes is the pair 15 in P. hastatus, a synapomorphy. The analysis of meiosis confirms that the X and Y have a pseudo-autosomal region, with a typical end-to-end pairing. The autosomal regions of the neo-XX/XY shows different levels of condensation when compared to the original XX/XY. The compound system presented a characteristic shape, as if it was a closed ring with a tail. The ring represents the non-paired segments of the X and Y and the small pairing region of the original sex chromosomes. The tail corresponds to the pairing of the 15 P. hastatus autosomal bivalent, which are translocated to the sex chromosomes. Probably the non-pairing is responsible for the meiotic silencing of these segments.
Instituto de Ciências Biológicas, Universidade Federal do Pará, Av Perimetral, sn. Campus do Guamá, Belém, Pará, 66075-900, Brazil.
This article was published in the following journal.
Characidium constitutes an interesting model for cytogenetic studies, since a large degree of karyotype variation has been detected in this group, like the presence/absence of sex and supernumerary ch...
B chromosomes are dispensable genomic elements found in different groups of animals and plants. In the present study, a whole chromosome probe was generated from a specific heterochromatic B chromosom...
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Sites and amounts of 5-methylcytosine (5-MeC)-rich chromosome regions were detected in the karyotypes of 9 Brazilian species of Characiformes fishes by indirect immunofluorescence using a monoclonal a...
The purpose of this research is to study a new way to test for chromosome abnormalities. Chromosomes are strands of DNA (the genetic material in the cell nucleus) that are made up of genes...
Our aims is to document the possible effect of cryo- preservation at the meiotic spindle and mitochondrial levels.
The researchers' laboratory is studying a rare class of highly recurrent hydatidiform moles. These are usually complete hydatidiform moles (CHM), but sometimes they are partial hydatidifo...
RATIONALE: Studying the chromosomes in samples of bone marrow and blood in the laboratory from patients with cancer or other blood diseases may help doctors learn more about the disease. ...
Our vision, that of the researchers at the University of Texas Health Science Center at San Antonio, is that every person with a chromosome 18 abnormality will have an autonomous and healt...
A technique for visualizing CHROMOSOME ABERRATIONS using fluorescently labeled DNA probes which are hybridized to chromosomal DNA. Multiple fluorochromes may be attached to the probes. Upon hybridization, this produces a multicolored, or painted, effect with a unique color at each site of hybridization. This technique may also be used to identify cross-species homology by labeling probes from one species for hybridization with chromosomes from another species.
The reciprocal exchange of segments at corresponding positions along pairs of homologous CHROMOSOMES by symmetrical breakage and crosswise rejoining forming cross-over sites (HOLLIDAY JUNCTIONS) that are resolved during CHROMOSOME SEGREGATION. Crossing-over typically occurs during MEIOSIS but it may also occur in the absence of meiosis, for example, with bacterial chromosomes, organelle chromosomes, or somatic cell nuclear chromosomes.
Staining of bands, or chromosome segments, allowing the precise identification of individual chromosomes or parts of chromosomes. Applications include the determination of chromosome rearrangements in malformation syndromes and cancer, the chemistry of chromosome segments, chromosome changes during evolution, and, in conjunction with cell hybridization studies, chromosome mapping.
The homologous chromosomes that are dissimilar in the heterogametic sex. There are the X CHROMOSOME, the Y CHROMOSOME, and the W, Z chromosomes (in animals in which the female is the heterogametic sex (the silkworm moth Bombyx mori, for example)). In such cases the W chromosome is the female-determining and the male is ZZ. (From King & Stansfield, A Dictionary of Genetics, 4th ed)
A subdiscipline of genetics which deals with the cytological and molecular analysis of the CHROMOSOMES, and location of the GENES on chromosomes, and the movements of chromosomes during the CELL CYCLE.
Bioinformatics is the application of computer software and hardware to the management of biological data to create useful information. Computers are used to gather, store, analyze and integrate biological and genetic information which can then be applied...