Artículos de revistas
Natural triploidy and B chromosomes in Astyanax scabripinnis (Characiformes, Characidae): a new occurrence
Fecha
2012-01-01Registro en:
Caryologia. Florence: Univ Florence Botany Inst, v. 65, n. 1, p. 40-46, 2012.
0008-7114
10.1080/00087114.2012.678086
WOS:000310431600007
0804793944846367
0297419882161114
0000-0002-4143-7212
Autor
Universidade Estadual Paulista (Unesp)
Universidade Estadual de Ponta Grossa (UEPG)
Univ Granada
Institución
Resumen
Several cases of natural triploidy have already been described in fish, however this is the first report of a surviving triploid that also carries two different supernumerary chromosomes. Cytogenetic analysis of an Astyanax scabripinnis population revealed a standard karyotype of 2n = 50, with a chromosome formula consisting of: 6 metacentric + 16 submetacentric + 14 subtelocentric + 14 acrocentric chromosomes. In addition, specimens showed a polymorphism for the presence of up to two supernumerary chromosomes. Among the specimens analyzed one was a natural triploid (with 75 chromosomes) that also carried a small sized and a macro-supernumerary chromosome. The co-occurrence of spontaneous triploidy and two supernumerary chromosome indicates the viability of this karyotype constitution as well as this fish capacity of tolerating extra chromosomes in large numbers.