ISSN:
1573-6849
Keywords:
chromosome banding
;
Hoplias malabaricus
;
inactive centromere
;
sex chromosomes
;
translocation rearrangement
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Hoplias malabaricus, a widely distributed neotropical fish (Central America to Argentina), may represent a group of distinct species showing diversified cytotypes with respect to chromosome number, morphology and sex systems. One of these karyotypic forms is characterized by an X1X1X2X2/X1X2Y sex chromosome system, with 2n= 40 and 39 chromosomes in females and males respectively. Analyses with G-, C- and chromosome replication banding permitted a better characterization of the sex chromosomes in this cytotype. The Y chromosome, unique in males, resulted from a translocation event between two biarmed chromosomes: one similar to chromosome 6 (X1) and the other one similar to chromosome 20 (X2), the latter corresponding to a probable identification. On the basis of the observed banding patterns, the Y chromosome may represent a stable dicentric, with an inactive centromere interstitially located on its long arm. The results are also related to a specific satellite DNA subfamily, previously characterized in Hoplias malabaricus, which appears to be associated with the X1 chromosome.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1018477232354
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