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First description of B chromosomes in the Hyphessobrycon (Characiformes, Characidae) genus: A hypothesis for the extra element of Hyphessobrycon eques Steindachner, 1882
(2015-01-01)
The Hyphessobrycon are allocated in the incertae sedis group of the Characidae family, one of the genera with more species of the group. The chromosomes of some species of Hyphessobrycon are known, and the diploid number ...
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 ...
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 ...
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 ...
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 Characidium alipioi (Characiformes, Crenuchidae) and its relationship with supernumerary chromosomes in other Characidium species
(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 ...
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 ...
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 ...
Isochromosome Y in an infertile heifer
(1990-11-23)