Wiwat Sangpakdee

Karyotypic study of five Lutjanid species using conventional and Ag-NORs banding techniques

The first cytogenetic comparisons of five snapper species from Thailand were presented here. Renal cell samples were taken from blacktail snapper (Lutjanus fulvus), five lined snapper (L. quinquelineatus), dory snapper (L. fulviflamma), brownstripe red snapper (L. vitta), and mangrove red snapper (L. argentimaculatus). The mitotic chromosome preparation was prepared directly from kidney cells. Conventional staining and Ag-NOR banding techniques were applied to stain the chromosomes. The results exhibited that all five snapper species have the diploid chromosome numbers of 2n = 48 and the fundamental numbers (NF) of 48. The presences of large, medium, and small telocentric chromosomes were 22-24-2, 24-20-4, 36-10-2, 28-16-4 and 36-10-2, respectively. The Ag- NORs banding technique provides the pair of nucleolar organizer regions (NORs) at subcentromeric region of the long arm of the respective telocentric chromosome pairs 9, 1, 3, 4 and 9. Their karyotype formulas is as follows: L. fulvus (2n = 48): L22t + M24t + S2t, L. quinquelineatus (2n = 48): L24t + M20t + S4t, L. fulviflamma (2n = 48): Lt36 + Mt10 + St2, L. vitta (2n = 48): L28t + M16t + S4t, and L. argentimaculatus (2n = 48): L36t + M10t + S2t.

Molecular Cytogenetic Analysis of One African and Five Asian Macaque Species Reveals Identical Karyotypes as in Mandrill

Background: The question how evolution and speciation work is one of the major interests of biology. Especially, genetic including karyotypic evolution within primates is of special interest due to the close phylogenetic position of Macaca and Homo sapiens and the role as in vivo models in medical research, neuroscience, behavior, pharmacology, reproduction and Acquired Immune Deficiency Syndrome (AIDS). Materials & Methods: Karyotypes of five macaque species from South East Asia and of one macaque species as well as mandrill from Africa were analyzed by high resolution molecular cytogenetics to obtain new insights into karyotypic evolution of old world monkeys. Molecular cytogenetics applying human probes and probe sets was applied in chromosomes of Macaca arctoides, M. fascicularis, M. nemestrina, M. assamensis, M. sylvanus, M. mulatta and Mandrillus sphinx. Established two- to multicolor-fluorescence in situ hybridization (FISH) approaches were applied. Locus-specific probes, whole and partial chromosome paint probes were hybridized. Especially the FISH-banding approach multicolor-banding (MCB) as well as probes oriented towards heterochromatin turned out to be highly efficient for interspecies comparison. Conclusion: Karyotypes of all seven studied species could be characterized in detail. Surprisingly, no evolutionary conserved differences were found among macaques, including mandrill. Between the seven here studied and phenotypically so different species we expected several via FISH detectable karyoypic and submicroscopic changes and were surprised to find none of them on a molecular cytogenetic level. Spatial separation, may explain the speciation and different evolution for some of them, like African M. sylvanus, Mandrillus sphinx and the South Asian macaques. However, for the partially or completely overlapping habitats of the five studied South Asian macaques the species separation process can also not be deduced to karyotypic separation.

First chromosome characterization in the large indian civet, Viverra zibetha (Carnivora, Viverridae) in Thailand by conventional staining and GTG-banded technique

Abstract This research was the first cytogenetic study of large Indian civet (Viverra zibetha) in Thailand. Blood samples of the species were taken from two males and one female kept in Songkhla Zoo, Songkhla province, Thailand. After the standard whole blood lymphocyte culture in presence of colchicine, the metaphase spreads were performed on microscopic slides and air-dried. Conventional staining and GTG-banded technique were applied to stain the chromosomes. The karyotype of large Indian civet show that diploid chromosome number was 2n=38, and the fundamental number (NF) were 72 in female and 71 in male. The autosomes consist of 4 large metacentric, 10 large submetacentric, 10 large acrocentric, 2 large telocentric, 2 medium metacentric, 2 medium acrocentric, 4 small acrocentric and 2 small telocentric chromosomes. The X chromosome was large submetacentric and the Y chromosome was the smallest telocentric chromosome. Idiogram represent banding pattern at the metaphase chromosome was 345 bands and found that chromosome pairs 13 was the satellite marker chromosome that have secondary constriction on long length arm. These results will be useful for future studies of breeding, conservation, chromosome evolution and basic genetics information in this species.