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A cytophotometric study of chromosome pairing
Chromosoma, 19561. Confirming earlier studies (Schrader 1945a and b), the chromosomes of the harlequin lobe of the testis of the pentatomid Loxa flavicolis are found to be asynaptic throughout late meiotic prophase and to divide equationally at metaphase I. All other lobes show a normal meiosis. 2.
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Mechanism of Chromosome Pairing during Meiosis
Nature, 1970Electron microscopy with whole mount preparations has revealed that the synaptonemal complex merely pulls two homologous chromosomes together. Intimate molecular pairing is another matter—probably brought about by connexions between short stretches of single stranded DNA.
David E. Comings, Tadashi A. Okada
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Chromosome pairing in haploids of Brassica campestris
Theoretical and Applied Genetics, 1981The maximum chromosome pairing observed in haploids of Brassica campestris was two bivalents plus one trivalent but differences were observed in the chromosome pairing frequencies of the four haploids studied. This pairing supports the theorem that the species is hexasomic for one chromosome, tetrasomic for two and disomic for three others but it is ...
K. C. Armstrong, W. A. Keller
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CHROMOSOME PAIRING AND PHYLOGENETIC AFFINITIES
TAXON, 1972SummaryThe mechanisms of chromosome pairing are poorly understood. Yet, pairing during meiotic prophase is commonly assumed to indicate homology, and absence of pairing non‐homology between parental genomes. These assumptions lead to the widely accepted belief that data on chromosome pairing in hybrids provide indisputable evidence of degree of ...
J. M. J. Wet, J. R. Harlan
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The Analysis of Chromosome Pairing
1975In respect to chromosome pairing, two situations may be distinguished: non-competitive pairing, in which only two possible partners are available, and competitive pairing, where more than two potential partners are available, but where nevertheless only two at a time can finally pair sufficiently effectively to form a chiasma.
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Triple Chromosome Pairing in Triploid Chickens
Nature, 1971THE statement that “only two homologous chromosomes can pair at one time” is one of the most basic of cytogenetic principles. It is founded on observations of meiosis in triploid and tetraploid organisms1–7 which have suggested that if three homologues are present, they will occur as a pair and a single unpaired chromosome.
David E. Comings, Tadashi A. Okada
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Chromosome pairing and induced exchange in Drosophila
Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis, 1965Abstract Fragments of Y chromosomes were induced by irradiating attached-X Drosophila melanogaster females carrying a doubly marked Y chromosome, and detected by loss of one of the Y markers. Slightly more than half of the 55 fragments recovered showed linkage of fourth chromosome markers, implying a high frequency of association of Y and fourth ...
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Classifier-assisted metric for chromosome pairing
2010 Annual International Conference of the IEEE Engineering in Medicine and Biology, 2010Cytogenetics plays a central role in the detection of chromosomal abnormalities and in the diagnosis of genetic diseases. A karyogram is an image representation of human chromosomes arranged in order of decreasing size and paired in 23 classes. In this paper we propose an approach to automatically pair the chromosomes into a karyogram, using the ...
Rodrigo Ventura +2 more
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The meiotic pairing of nine wheat chromosomes
Theoretical and Applied Genetics, 1984The meiotic identification of nine pairs of chromosomes at metaphase I of meiosis of Triticum aestivum (B genome, 4A and 7A) has been achieved using a Giemsa C-banding technique. As a result, the analysis of the pairing of each chromosome arm in disomic and monosomic intervarietal hybrids between 'Chinese Spring' and the Spanish cultivar 'Pané 247 ...
Nicolás Jouve +2 more
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POLYPLOIDY AND DIPLOIDY: NEW PERSPECTIVES ON CHROMOSOME PAIRING AND ITS EVOLUTIONARY IMPLICATIONS
, 1982The last widely accepted classification of polyploidy recognized three major categories: autoploidy, segmental alloploidy, and true alloploidy. Criteria for recognizing these types were based largely on chromosome pairing in F1 hybrids, but until very ...
R. C. Jackson
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