Now showing items 31-40 of 6874
Cytogenetic mapping of the W chromosome in the genus Leporinus (Teleostei, Anostomidae) using a highly repetitive DNA sequence
The distribution of the Leporinus elongatus LeSpeI repetitive sequence in other Leporinus species was studied in an attempt to elucidate the evolutionary history of sex chromosomes in this genus using chromosome fluorescence ...
B-chromosomes in two Brazilian populations of Dendropsophus nanus (Anura, Hylidae)
(Sociedade Brasileira de Genética, 2006-01-01)
We report on the presence of B-chromosomes in two populations of Dendropsophus nanus (= Hyla nana Boulenger, 1889) from São Paulo State, Brazil. Such chromosomes were observed in 4 out of 43 specimens (9.3%) and in 9 out ...
Different responses to doxorubicin-induced chromosome aberrations in Brazilian deer species
The tendency toward chromosome fragility is one of the theories that may explain chromosome variation in brocket deer species (genus Mazama). We tested doxorubicin as an inducer of chromosome aberrations in lymphocytes of ...
Identifying Mazama gouazoubira (Artiodactyla; Cervidae) chromosomes involved in rearrangements induced by doxorubicin
The process of karyotype evolution in Cervidae from a common ancestor (2n = 70, FN = 70) has been marked by complex chromosomal rearrangements. This ancestral karyotype has been retained by the current species Mazama ...
Interstitial long-arm deletion of chromosome 7 and ectrodactyly
An interstitial deletion of 7q21 was found in a boy with mental retardation, microcephaly, convergent strabismus, micrognathia, genital anomalies, and other findings, including ectrodactyly.
Cytogenetic analysis of A-, B-chromosomes and ZZ/ZW sex chromosomes of Characidium gomesi (Teleostei, Characiformes, Crenuchidae)
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 ...
Characteristics of NOR-banded chromosomes of Mangalarga horses
The nucleolar organizer regions (NORs) of Mangalarga horses were characterized by analysis of NOR-banded metaphase chromosomes according to the technique of Goodpasture and Bloom (Chromosoma 53: 37-50, 1975). NOR banding ...
The contrasting role of heterochromatin in the differentiation of sex chromosomes: an overview from Neotropical fishes
During the evolutionary process of the sex chromosomes, a general principle that arises is that cessation or a partial restriction of recombination between the sex chromosome pair is necessary. Data from phylogenetically ...
Possible origin of B chromosome in Dichotomius sericeus (Coleoptera)
(Canadian Science Publishing, Nrc Research Press, 2016-08-01)
B chromosomes have so far been described in about 80 species of Coleoptera, mainly using conventional staining analysis. In this study, 152 individuals of the dung beetle Dichotomius sericeus (Coleoptera), collected from ...