Karyotype and chromosome location of characteristic tandem repeats in the pufferfish Tetraodon nigroviridis

Cytogenet Cell Genet. 2000;88(1-2):50-5. doi: 10.1159/000015484.


Karyotype analysis of Tetraodon nigroviridis, a pufferfish of the family Tetraodontidae with a small compact genome (385 Mb) which is currently being investigated in our laboratory, indicates that this species has 2n = 42 chromosomes. The small chromosome size (the largest pair measuring less than 3 microm) has complicated accurate chromosome pairing based on morphology alone. DAPI staining, however, provides a banding-like pattern. Because of quantitative variations of some heterochromatin classes, the chromosome formula can not be established precisely, but is estimated to include approximately 20 meta- or submetacentric chromosomes and 22 subtelocentric chromosomes. A centromeric satellite, telomeric repeats, and the major and minor rRNA clusters have been localized unequivocally by FISH. As a result, the 28S and 5S rDNA sequences can be used as chromosome-specific probes.

MeSH terms

  • Animals
  • Centromere / genetics
  • Chromosome Banding / methods
  • DNA Probes / genetics
  • DNA, Ribosomal / genetics
  • DNA, Satellite / genetics
  • Female
  • Fishes / genetics*
  • Genetic Markers / genetics
  • Heterochromatin / genetics
  • In Situ Hybridization, Fluorescence
  • Indoles / metabolism
  • Karyotyping / methods
  • Male
  • Nucleolus Organizer Region / genetics
  • Physical Chromosome Mapping / methods*
  • Polymorphism, Genetic / genetics
  • Tandem Repeat Sequences / genetics*
  • Telomere / genetics


  • DNA Probes
  • DNA, Ribosomal
  • DNA, Satellite
  • Genetic Markers
  • Heterochromatin
  • Indoles
  • DAPI