SciELO - Scientific Electronic Library Online

 
vol.34 issue4Chromosome 19p13.3 deletion in a child with Peutz-Jeghers syndrome, congenital heart defect, high myopia, learning difficulties and dysmorphic features: clinical and molecular characterization of a new contiguous gene syndromeRelative contribution of effects included in contemporary groups for adjusted and actual 120-day and 210-day weights in Nelore cattle in Brazil author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Genetics and Molecular Biology

Print version ISSN 1415-4757

Abstract

MARTINEZ, Emanuel Ricardo Monteiro; ZAWADZKI, Claudio Henrique; FORESTI, Fausto  and  OLIVEIRA, Claudio. Cytogenetic analysis of five Hypostomus species (Siluriformes, Loricariidae). Genet. Mol. Biol. [online]. 2011, vol.34, n.4, pp. 562-568.  Epub Aug 26, 2011. ISSN 1415-4757.  http://dx.doi.org/10.1590/S1415-47572011005000038.

In this work, we analyzed the karyotypes of five species. Hypostomus cf. heraldoi, from the Mogi-Guaçu River, had 2n = 72 chromosomes, with a nucleolar organizer region (NOR) in one chromosomal pair. Hypostomus regani, from the Mogi-Guaçu River had 2n = 72 chromosomes with NORs in two chromosomal pairs. Hypostomus sp., from the Mogi-Guaçu River basin, had 2n = 68 chromosomes, with NORs in two chromosomal pairs. Hypostomus aff. agna, from Cavalo Stream, had 2n = 74 chromosomes with NORs in two chromosomal pairs. Hypostomus cf. topavae, from Carrapato Stream, had 2n = 80 chromosomes, with NORs in two chromosomal pairs. Hypostomus species showed marked diversity in the karyotypic formula, which suggested the occurrence of several Robertsonian rearrangements and pericentric inversions during the evolutionary history of this genus. This hypothesis was supported by the occurrence of a large number of uniarmed chromosomes and multiple NORs in a terminal position in most species and may be a derived condition in the Loricariidae.

Keywords : chromosomes; evolution; Hypostominae; Neotropical fish; NOR.

        · text in English     · pdf in English