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Velocardiofacial syndrome with a rare t(2;22)
(2007-07-01)
Rearrangements involving chromosomes 2 and 22 were described not only as acquired abnormalities in a variety of human neoplasias but also in the constitutional karyotype suggesting the existence of a greater fragility in ...
Study of chromosomal and nucleolar aspects in testes of Nysius californicus (Heteroptera: Lygaeidae)
(2007-05-18)
In Nysius californicus (family Lygaeidae, subfamily Orsillinae), a pest commonly known as the seed bug, the chromosome complement is 2n = 16 (12A + 2m + XY), testes are formed by seven seminiferous tubules covered by an ...
Differential characterization of holocentric chromosomes in triatomines (Heteroptera, Triatominae) using different staining techniques and fluorescent in situ hybridization
(2007-11-19)
A comparative study of holocentric chromosomes in the triatomine species Panstrongylus megistus, Rhodnius pallescens and Triatoma infestans was carried out in order to characterize heterochromatin, rDNA active sites and ...
Heteropicnotic chromatin and nucleolar activity in meiosis and spermiogenesis of Limnogonus aduncus (Heteroptera, Gerridae): a stained nucleolar organizing region that can serve as a model for studying chromosome behavior.
(2008-12-01)
Males of Limnogonus aduncus were found to have the sex chromosome system X0 and chromosome number 2n = 23 (22A + X0). Testis cells were stained with lacto-acetic orcein and silver nitrate so that changes in the morphology ...
Unusual occurrence of a ZZ/ZW sex-chromosome system and supernumerary chromosomes in Characidium cf. fasciatum (Pisces, Characiformes, Characidiinae)
(Kluwer Academic Publ, 1998-01-01)
Individuals of two populations of the fish Characidium cf. fasciatum were cytogenetically studied and showed a basic diploid number of 50 chromosomes. Some fishes were found to have 51 to 54 chromosomes due to the presence ...
Origin of B chromosomes in the genus Astyanax (Characiformes, Characidae) and the limits of chromosome painting
(Springer, 2016-06-01)
Eukaryote genomes are frequently burdened with the presence of supernumerary (B) chromosomes. Their origin is frequently investigated by chromosome painting, under the hypothesis that sharing the repetitive DNA sequences ...
Origin of B chromosomes in Characidium alipioi (Characiformes, Crenuchidae) and its relationship with supernumerary chromosomes in other Characidium species
(Pensoft Publ, 2017-01-01)
B chromosomes are apparently dispensable components found in the genomes of many species that are mainly composed of repetitive DNA sequences. Among the numerous questions concerning B chromosomes, the origin of these ...
Localization of rDNA sites in holocentric chromosomes of three species of triatomines (Heteroptera, Triatominae).
(2005-12-30)
Chromatin organization in the holocentric chromosomes of three triatomines species was cytologically studied by fluorescent in situ hybridization with a 45S rDNA probe of Drosophila melanogaster to localize ribosomal genes. ...