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A novel ZZ/ZW sex chromosome system for the genus Leporinus (Pisces, Anostomidae, Characiformes)
(Kluwer Academic Publ, 2004-05-01)
A wide range of sex chromosome mechanisms, including simple and multiple chromosome systems is characteristic of fishes. The Leporinus genus represent a good model to study sex chromosome mechanisms, because an unambiguous ...
Cytogenetic analysis of A-, B-chromosomes and ZZ/ZW sex chromosomes of Characidium gomesi (Teleostei, Characiformes, Crenuchidae)
(2004-06-01)
Different cytogenetic techniques were used to analyze the chromosomes of Characidium gomesi with the main objective of comparing the base composition of ZZ/ZW sex-chromosomes, B-chromosomes and the heterochromatin of ...
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 ...
Description of a ZZ/ZW sex chromosome system in Thoracocharax cf. stellatus (Teleostei, Characiformes, Gasteropelecidae)
(Sociedade Brasileira de Genética, 2002-01-01)
The family Gasteropelecidae is composed of three genera and eight species. This study shows that Thoracocharax cf. stellatus has 2n = 52 chromosomes for both sexes. The five males studied showed 8 metacentric, 16 submetacentric, ...
Occurrence of ZZ/ZW sex chromosomes in Thoracocharax stellatus fish (Characiformes, Gasteropelecidae) from the Araguaia River, south America
(Springer, 2008-06-01)
The karyotypic and chromosomal characteristics of the hatchetfish Thoracocharax stellatus from the Araguaia River, Brazil (Araguaia-Tocantins basin) were analyzed using Giemsa, AgNO3, and CMA(3) fluorescent staining, and ...
Morphologically differentiated sex chromosomes in neotropical freshwater fish
(2001-12-01)
A general survey of the occurrence of morphologically differentiated sex chromosomes in the neotropical freshwater fishes is presented. The total number of 32 occurrences involving simple XX-XY and ZZ-ZW, and multiple ...
SEX-CHROMOSOME POLYMORPHISM AND HETEROGAMETIC MALES REVEALED BY 2 CLONED DNA PROBES IN THE ZW ZZ FISH LEPORINUS-ELONGATUS
(Springer, 1994-03-01)
In order to study the divergence of teleost sex chromosomes, subtractive cloning was carried out between genomic DNA of males and females of the rainbow trout (XX/XY) and of Leporinus elongatus (ZW/ZZ). Inserts cloned in ...
CHROMOSOME-STUDIES IN HYPOPTOPOMATINAE (PISCES, SILURIFORMES, LORICARIIDAE) .2. ZZ ZW SEX-CHROMOSOME SYSTEM, B-CHROMOSOMES, AND CONSTITUTIVE HETEROCHROMATIN DIFFERENTIATION IN MICROLEPIDOGASTER-LEUCOFRENATUS
(Karger, 1993-01-01)
Cytogenetic analysis of two local populations of microlepidogaster leucofrenatus showed a basic diploid chromosome number (2N) of 54 in both populations. Some fishes were found to have a 2N = 55 or 56 chromosomes due to ...
Chromosome painting of Z and W sex chromosomes in Characidium (Characiformes, Crenuchidae)
(2013-01-24)
Some species of the genus Characidium have heteromorphic ZZ/ZW sex chromosomes with a totally heterochromatic W chromosome. Methods for chromosome microdissection associated with chromosome painting have become important ...
Identification of a new repetitive element in the sex chromosomes of Leporinus elongatus (Teleostei : Characiformes : Anostomidae): new insights into the sex chromosomes of Leporinus
(Karger, 2007-01-01)
Leporinus elongatus represents an interesting model for studies on chromosome evolution since it possesses a conspicuous ZZ/ZW sex chromosome system that has been characterized mainly by basic cytogenetic techniques. In ...