Classical chromosome features and microsatellites repeat in Gekko petricolus (Reptilia, Gekkonidae) from Thailand

The objectives of this study were to examine size, shape, diploid number (2n), fundamental number (NF), NORs region, and distribution of microsatellite by using Fluorescence in situ hybridization technique (FISH) and to establish the karyotype and standard idiogram of sandstone geckos (Gekko petricolus Taylor, 1962). Sandstone gecko distributed in the sandstone mountains in Laos, Cambodia, and Thailand. Five male and five female specimens were collected  from Ubon Ratchathani and Mukdahan provinces, Thailand. The metaphase cells were directly prepared from the bone marrow cells. Chromosomes were stained by conventional staining, NORs-banding and FISH techniques. The results found that the diploid number was 38 chromosomes. The fundamental number was 54. The karyotype composed of 4 large metacentric, 4 large acrocentric, 2 large telocentric, 4 medium acrocentric, 2 medium telocentric, 2 small submetacentric, 2 small acrocentric and 18 small telocentric chromosomes. No morphological difference was identified between sex chromosomes of male and female specimens. The NORs appeared to telomere of the long arm of chromosome pair 17. The study displayed that the distribution of microsatellite using (CA)15 and (GAA)10 probes distributed throughout the genome. However, (CA)15 sequences concentrated in the telomere. The karyotype formula G. petricolus is as follow: 2n (38) = Lm4+La4+Lt2+Ma4+Mt2+Ssm2+Sa2+St18.