Small Telocentric Chromosomes Research Articles

First report of chromosome and karyological analysis of Gekko nutaphandi (Gekkonidae, Squamata) from Thailand: Neo-diploid chromosome number in genus Gekko

The karyotypes of red-eyed Gecko are not reported yet. Herein, we describe the karyotypes of red-eyed Gecko (Gekko nutaphandi Bauer, Sumontha & Pauwels, 2008) from Thailand. Gecko chromosome preparations were directly conducted from bone marrow and testis. Chromosomal characteristics were analyzed by Giemsa staining, Ag-NOR banding as well as fluorescence in situ hybridization (FISH) using microsatellites d(GC)15 probe. The results showed that the number of diploid chromosomes is 2n=34, while the fundamental number (NF) is 46 in both males and females. The types of chromosomes were 4 large metacentric, 6 large submetacentric, 2 medium telocentric, 2 small metacentric and 20 small telocentric chromosomes. The results of conventional Giemsa staining presented the diploid chromosome number differentiation even in the same genus. NORs are located at the secondary constriction to the telomere on the long arm of chromosome pair 5. There are no sex differences in karyotypes between males and females. FISH with d(GC)15 sequences were also displayed at the telomeres of most other chromosomes. We found that during metaphase I the homologous chromosomes showed synapsis, which can be defined as 19 ring bivalents and 17 haploid chromosomes (n=17) at metaphase II as a diploid species. The karyotype formula is as follows: 2n (34) = L4m+L6sm+M2t+S2m+S20t.

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.

First report of karyological analysis and heteromorphic nucleolar organizer region of Black Surgeonfish (Acanthurus gahhm, Acanthuridae) in Thailand

This research was the first report on karyological analysis and heteromorphic nucleolar organizer region of black surgeonfish (Acanthurus gahhm, Acanthuridae) in Thailand. The 10 male and 10 female specimens were collected from Phuket Marine Biological Center, and Phang Nga Coastal Research and Development Center, Andaman Sea, Thailand. Mitotic chromosomes were directly prepared from gill and kidney tissues. The chromosomes were stained by conventional Giemsa staining and Ag-NOR banding techniques. Results showed that the diploid chromosomes number of A. gahhm was 2n=48, the fundamental numbers (NF) was 54 in both male and female. The karyotype consist of 6 large acrocentric, 20 large telocentric, 18 medium telocentric and 4 small telocentric chromosomes. None of strange size chromosomes related to sex was found. The heteromorphic nucleolar organizer regions (NORs) were observed on telomeric short arm of first acrocentric which can defined as 1a1b. There is NOR in 1a and not in 1b. The karyotype formula of black surgeon fish was as follows: 2n (48) = La6+Lt20+Mt18+St4

The somatic chromosomes of F1 hybrid male deer (Hyelaphus porcinus × Axis axis) by comparative banding techniques

The chromosome analyses of F1 hybrid male deer from the cross of Hyelaphus porcinus male and Axis axis female have been presented. Chromosomes were prepared from T-lymphocyte by conventional staining and GTC-banding techniques. The results showed that the diploid chromosome number of F1 hybrid male deer was 2n = 67, fundamental number was 70. The special karyotype consisted of 2 large metacentric, 1 large submetacentric, 13 large telocentric, 18 medium telocentric and 31 small telocentric chromosomes. The X-chromosome was large telocentric chromosome and Y-chromosome was small acrocentric chromosome. The amount of GTG-banding pattern on a set of haploid number (n) in the hybrid were 261 bands. The GTG-banding comparison of hybrid deer and the parents has been shown with the deduced karyotype formula as: 2n (67) = Lm2 + Lsm1 + Lt13 + Mt18 + St31 + sex chromosomes

Chromosome evolution in Cophomantini (Amphibia, Anura, Hylinae).

The hylid tribe Cophomantini is a diverse clade of Neotropical treefrogs composed of the genera Aplastodiscus, Boana, Bokermannohyla, Hyloscirtus, and Myersiohyla. The phylogenetic relationships of Cophomantini have been comprehensively reviewed in the literature, providing a suitable framework for the study of chromosome evolution. Employing different banding techniques, we studied the chromosomes of 25 species of Boana and 3 of Hyloscirtus; thus providing, for the first time, data for Hyloscirtus and for 15 species of Boana. Most species showed karyotypes with 2n = 2x = 24 chromosomes; some species of the B. albopunctata group have 2n = 2x = 22, and H. alytolylax has 2n = 2x = 20. Karyotypes are all bi-armed in most species presented, with the exception of H. larinopygion (FN = 46) and H. alytolylax (FN = 38), with karyotypes that have a single pair of small telocentric chromosomes. In most species of Boana, NORs are observed in a single pair of chromosomes, mostly in the small chromosomes, although in some species of the B. albopunctata, B. pulchella, and B. semilineata groups, this marker occurs on the larger pairs 8, 1, and 7, respectively. In Hyloscirtus, NOR position differs in the three studied species: H. alytolylax (4p), H. palmeri (4q), and H. larinopygion (1p). Heterochromatin is a variable marker that could provide valuable evidence, but it would be necesserary to understand the molecular composition of the C-bands that are observed in different species in order to test its putative homology. In H. alytolylax, a centromeric DAPI+ band was observed on one homologue of chromosome pair 2. The band was present in males but absent in females, providing evidence for an XX/XY sex determining system in this species. We review and discuss the importance of the different chromosome markers (NOR position, C-bands, and DAPI/CMA3 patterns) for their impact on the taxonomy and karyotype evolution in Cophomantini.

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): L 22 t + M 24 t + S 2 t , L. quinquelineatus (2n = 48): L 24 t + M 20 t + S 4 t , L. fulviflamma (2n = 48): Lt36 + Mt10 + St2, L. vitta (2n = 48): L 28 t + M 16 t + S 4 t , and L. argentimaculatus (2n = 48): L 36 t + M 10 t + S 2 t .

Karyological characteristics of the Koh Tao caecilian, Ichthyophis kohtaoensis (Amphibia: Gymnophiona: Ichthyophiidae) by conventional staining and Ag-NOR banding techniques

The karyotypic analysis of the Koh Tao caecilian, Ichthyophis kohtaoensis Taylor, on 1960 from Surin Province, Thailand was obtained from the present study. Mitotic chromosome was prepared directly from the small intestine of specimens after in vivo colchicine treatment. The metaphase spreads were performed on microscopic slides and air-dried. Conventional staining, and Ag-NOR banding techniques were applied to stain the chromosome with Giemsa’s solution. Results showed that the number of diploid chromosome was 2n = 42, while the fundamental number (NF) was 64 in both males and females. The type of chromosomes included 6 large metacentric, 2 large submetacentric, 12 small metacentric, 2 small submetacentric, and 20 small telocentric chromosomes. We found that nucleolar organizer regions/NORs (the representative of chromosome marker) were located on the small telocentric chromosome pair 19. No cytologically distinguishable sex chromosome was observed. The karyotype formula is as follows: 2n (42) = L 6 m + L 2 sm + S 12 m + S 2 sm + S 20 t .

Karyological analysis of the shrimp Palaemon serratus (Decapoda: Palaemonidae)

Analysis of metaphases of Palaemon serratus (Pennant, 1777) revealed a diploid number of 2n=56 chromosomes with a karyotype composed of two large metacentric pairs, six subtelocentric pairs and twenty telocentric pairs. Four Ag-NORs and 45S rDNA signals were observed at the telomeres of two small telocentric chromosome pairs. Chromomycin A3 fluorochrome staining revealed GC-rich regions associated with Ag-NORs, and DAPI showed positive bright bands on centromeric or intercalary positions of subtelocentric and telocentric chromosomes.

Karyological Analysis and Morphometrics of Horsfield's Bat, <i>Myotis horsfieldii</i> (Chiroptera, Vespertilionidae)

Karyological analysis and morphometrics of Horsfield’s bat (Myotis horsfieldii) from Thailand were studied. Blood samples were taken from five male and five female bats. After standard whole blood lymphocytes were cultured at 37°C for 72 h in presence of colchicine, metaphase spreads were performed on microscopic slides and air-dried. Conventional staining and GTGbanding techniques were applied to stain the chromosome. The results showed that the diploid chromosome number of M. horsfieldii was 2n=44, the fundamental number (NF) was 52 in both male and female. The types of autosomes observed were 6 large metacentric, 4 medium telocentric, 2 small metacentric, 2 small submetacentric, and 28 small telocentric chromosomes. The X chromosome was a large submetacentric chromosome and the Y chromosome was a small acrocentric chromosome. From the GTG-banding technique, the number of bands and location in M. horsfieldii was observed to be 195, and each chromosome pair could be clearly differentiated. Six external morphological characters were measured as well as 13 cranial and dental measurements. The karyotype formula of M. horsfieldii is as follows: 2n (44)=L6 +M4+S2 +S2+S28 t +XY

Standardized Karyotype and Idiogram of Titan Triggerfish, <i>Balistoides viridescens</i> (Tetraodontiformes, Balistidae) in Thailand

The standardized karyotype and idiogram of the titan triggerfish, Balistoides viridescens (Bloch & Schneider 1801) from Phuket Province, Thailand, were obtained from the present study. Kidney cell samples were taken from five male and five female fish. The mitotic chromosome preparations were conducted directly from the kidney cells. Conventional staining and Ag-NOR banding techniques were applied to stain the chromosomes. The results indicated that the diploid chromosome number of B. viridescens was 2n=44, and the fundamental number (NF) was 60 in both sexes. The chromosome types consist of 2 large metacentric, 4 large acrocentric, 2 large telocentric, 8 medium acrocentric, 10 medium telocentric, 2 small acrocentric, and 16 small telocentric chromosomes. No strange-sized chromosomes related to sex was observed. The region adjacent to the subtelomeric of short arm of chromosome pair 3 showed clearly observable secondary constriction/NORs. The karyotype formula for B. viridescens is as follows: 2n (diploid) 44=L2 +La 4+L2+M8+M10+S 2+S16

A Discovery of Nucleolar Organizer Regions (NORs) Polymorphism and Karyological Analysis of Smith's Barb, <i>Puntioplites proctozysron</i> (Cypriniformes, Cyprinidae) in Thailand

A discovery of nucleolar organizer regions (NORs) polymorphism and karyological analysis in the Smith's barb, Puntioplites proctozysron (Bleeker, 1865) from Nong Khai province, in the northeast of Thailand, were studied. Blood samples were taken from 4 male and 4 female fish. After standard whole blood lymphocytes had been cultured at 27°C for 96 hours in the presence of colchicine, metaphase spreads were performed on microscopic slides and air-dried. Conventional and Ag-NOR staining techniques were applied to stain the chromosome. The results showed that the diploid chromosomes number of P. proctozysron was 2n=50 and the fundamental numbers (NF) of both sexes were 82. The types of autosomes were 4 large metacentric, 8 large submetacentric, 2 large acrocentric, 2 large telocentric, 2 medium metacentric, 6 medium submetacentric, 10 medium acrocentric, 14 medium telocentric and 2 small telocentric chromosomes. No strange size chromosomes related to sex were observed. In addition, the short arm near telomere of chromosome pair 4 showed clearly observable nucleolar organizer regions (NORs). This is the first report on polymorphism of NORs in P. proctozysron. The result showed that a heteromorphism in 1 female had a different size of NORs of chromosome pair 4 (4a4b), while 3 females and 4 males had an equal size of both chromosome pair 4 with a homomorphism (4a4a). The karyotype formula for P. proctozysron is as follows:2n (diploid) 50=L4m+L8sm+L2a+L2t+M2m+M6sm+M10a+M14t+S2t

Karyological Analysis and Morphometrics of the Lesser Asiatic House Bat, <i>Scotophilus kuhlii</i> (Chiroptera, Vespertilionidae)

Summary Karyological analysis and morphometrics of the lesser Asiatic house bat (Scotophilus kuhlii) from Thailand were studied. Blood samples were taken from 5 male and 5 female bats, lymphocytes were cultured at 37�C for 72 h in presence of colchicine, and metaphase spreads were performed on microscopic slides and air-dried. Conventional staining and GTG-banding techniques were applied to stain the chromosomes. The results showed that the diploid chromosome number of S. kuhlii was 2n=36, and the fundamental number (NF) was 52 in both male and female. The types of autosomes were 6 large metacentric, 4 large submetacentric, 6 large telocentric, 2 medium submetacentric, 10 medium telocentric, 2 small metacentric, and 4 small telocentric chromosomes. The X chromosome was a large submetacentric chromosome and the Y chromosome was the smallest acrocentric chromosome. The GTG-banding technique, indicated that the number of bands and locations in S. kuhlii was 167, and that each chromosome pair could be clearly differentiated. In addition, a pair of long arms near the centromere of chromosome pair 17 showed clearly observable nucleolar organizer regions (NORs). In terms of morphological measurement, the following measurements were taken 6 external morphological characters as well as 13 cranial and dental characters. The karyotype formula of S. kuhlii was as follows: 2n (36)=L m 6 + L sm 4 + L t + M sm 2 + M t + S m 2 + S t 4 + XY

Chromosome Studies in the Banded Palm Civet, Hemigalus derbyanus Thomas, 1915 (Carnivora, Viverridae) by Conventional Staining, GTG-Banding and High-Resolution Techniques

Cytogenetics of banded palm civet (Hemigalus derbyanus) in Thailand was studied. Blood samples were taken from 2 males and 2 females then subjected to standard whole blood T-lymphocyte culture. The samples were harvested by colchicine-hypotonic-fixation-air-drying technique and followed by conventional staining, GTG-banding and high-resolution techniques with Giemsa's. The results showed diploid number as 2n=42, and fundamental number (NF) as 81 in both male and 82 in female. The autosomes consist of 10 large submetacentric, 12 large acrocentric, 4 medium submetacentric, 4 small metacentric, 8 small submetacentric and 2 small telocentric chromosomes. We found that nucleolar organizer regions (the representative of chromosome marker) locate on the long arms of a pair metacentric autosome 15. The X chromosome was a large acrocentric chromosome while the Y chromosome was the smallest telocentric chromosome. From GTG-banding and high-resolution techniques, the numbers of bands and locations in banded palm civet were 218 and 244, respectively. Each homologous chromosome pair appears clearly differentiated.

Standardized karyotype of the three-spot gourami, Trichogaster trichopterus (Perciformes, Belontidae) from Thailand by conventional and Ag-NOR staining technique

Standardized karyotype and idiogram of the three-spot gourami (Trichogaster trichopterus) from local market in Roi-Et province, northeast Thailand, were studied. Kidney cell samples were taken from ten male and ten female fishes. The mitotic chromosome preparations were prepared by blood cell culture as well as directly from kidney cells. Conventional and Ag-NOR staining techniques were applied to stain the chromosomes. The results showed that diploid chromosome number of T. trichopterus was 2n = 46, the fundamental numbers (NF) were 46 in both male and female. The types of autosomes were 12 large telocentric, 32 medium telocentric and 2 small telocentric chromosomes. The region adjacent to the telomere of chromosome pair 2 showed clearly observable secondary constriction / NORs. The karyotype formula for T. trichopterus could be deduced as: \( {2}n\left( {\hbox{diploid}} \right){46} = {\hbox{L}}_{{12}}^{\rm{t}} + {\hbox{M}}_{{32}}^{\rm{t}} + {\hbox{S}}_2^{\rm{t}} \).

Cytogenetic Studies of Fishing Cat, Prionailurus viverrinus (Bennett 1833) and Asiatic Golden Cat, Catopuma temminckii (Vigors and Horsfield 1827) by Conventional Staining, G-banding and High-resolution Techniques

The fishing cat, Prionailurus viverrinus (Bennett 1833) and the Asiatic golden cat, Catopuma temminckii (Vigos and Horsfield 1827) are two of many wild cat species currently listed as vulnerable or endangered in Thailand. 20 conventional staining, G-banding and high-resolution metaphase spreads obtained from lymphocyte cultures were analyzed for each animal. The female fishing cat has diploid chromosome number of 2n=38 and the fundamental number (NF) was 74. There are 6 autosome types: A type had 6 large submetacentric, B type had 8 large acrocentric, C type had 4 large metacentric, D type had 4 medium and 4 small submetacentric, E type had 8 small metacentric and F type had 2 small telocentric chromosomes. The female Asiatic golden cat had 2n=38, and the NF was 72. There are 6 autosome types: A type had 4 large and 2 medium submetacentric, B type had 6 large and 2 medium acrocentric, C type had 4 large metacentric, D type had 8 small submetacentric, E type had 6 small metacentric and F type had 4 small telocentric chromosomes. The female fishing cat and the Asiatic golden cat have a pair of the short arm of chromosome E1 (chromosome pairs 14) showed clearly observable satellite chromosomes. The X chromosome was submetacentric chromosome. From G-banding and high-resolution technique, number of bands were 184, 211 and 204, 245, respectively. We found that chromosomes A1, A2, A3, B1, B2, B4, X (fishing cat) and A1, A2, A3, C2, D1, D4, E1, E2, E3, F1, F2, X (Asiatic golden cat) patterns are same as domestic cat (Felis catus) chromosomes. Chromosomes B3, C1, C2, D1, D2, D3, D4, E1, E2, E3, F1 (fishing cat) and C1, D2, D4 (Asiatic golden cat) are similar to those of domestic cat chromosomes. These results show the evolutionary relationship between the wild cat (fishing cat, Asiatic golden cat) and the domestic cat. The karyotype formula of the female fishing cat and the Asiatic golden cat are as follows:Fishing cat: 2n(38)=L4m+L6sm+L8a+M4sm+S8m+S4sm+S2t+sex chromosomes.Asiatic golden cat: 2n(38)=L4m+L4sm+L6a+M2sm+M2a+S6m+S8sm+S4t+sex chromosomes.

Karyological Study of the Jungle Cat, Felis chaus (Carnivora, Felidae) by Conventional Staining, G-banding and High-resolution Staining Technique

As an endangered species in Thailand, wild animal species of the jungle cat (Felis chaus) was selected for karyological study. Blood samples were taken from 2 males and 2 females. After the standard whole blood lymphocyte culture in the presence of colchicine, the metaphase spreads were performed on microscopic slides and air-dried. Conventional staining, G-banding and high-resolution staining technique were applied to stain the chromosomes. The results showed that 2n (diploid) of jungle cat was 38, and the fundamental number (NF) was 72 in the male and female. There are 6 autosome types: A type had 6 large submetacentric chromosomes, B type had 8 large acrocentric chromosomes, C type had 4 large metacentric chromosomes, D type had 8 small submetacentric chromosomes, E type had 6 small metacentric chromosomes and F type had 4 small telocentric chromosomes. A pair of the short arm of chromosome E1 (chromosome pairs 14) showed a clearly observable satellite chromosomes. The X chromosome was medium submetacentric chromosome and the Y chromosome was the smallest submetacentric chromosome. From the G-banding and high-resolution staining technique, the number of bands and locations in the jungle cat was 167 and 183 respectively, and each chromosome pair could be clearly differentiated. We found that chromosomes B1, B2, D1, D4, E3, F2 and X chromosome patterns were according to the domestic cat (Felis catus) chromosomes. Chromosomes A1, A2, A3, B3, B4, C1, C2, D2, E1, E2, F1 and Y-chromosome are similar to those of the domestic cat. These results show the evolutionary relationship between the jungle cat and domestic cat. The karyotype formula for the male and female jungle cat is as follows: 2n(38) = L4m + L6sm + L8a + S6m + S8sm + S4t + sex chromosomes.

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

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, Thai- land. 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.

Cytogenetic Study of the Leopard, Panthera pardus (Carnivora, Felidae) by Conventional Staining, G-banding and High-resolution Staining Technique

This is a cytogenetic study of the leopard, Panthera pardus (Carnivora, Felidae). Blood samples were taken from 2 males and 1 female. After the standard whole blood lymphocyte culture in the presence of colchicine, the metaphase spreads were performed on microscopic slides and air-dried. Conventional staining, G-banding and high-resolution staining technique were applied to stain the chromosomes. The results showed that 2n (diploid) of leopard was 38, and the fundamental number (NF) was 72 in the male and female. There are 6 autosome types: A type had 4 large submetacentric and 2 medium submetacentric chromosomes, B type had 4 large acrocentric and 4 medium acrocentric chromosomes, C type had 2 large metacentric and 2 medium metacentric chromosomes, D type had 8 small submetacentric chromosomes, E type had 6 small metacentric chromosomes and F type had 4 small telocentric chromosomes. A pair of the short arm of chromosome E1 (chromosome pairs 14) showed a clearly observable satellite chromosomes. The X chromosome was small submetacentric chromosome and the Y chromosome was the smallest submetacentric chromosome. From the G-banding and high-resolution staining technique, the number of bands and locations in the leopard was 163 and 191 respectively, and each chromosome pair could be clearly differentiated. We found that chromosomes A1, B3, B4, C1, C2, D1, D3, E1, E2, E3, F1, F2, X and Y chromosome patterns were according to the domestic cat (Felis catus) chromosomes. Chromosomes A2, A3, B1, B2, D2 and D4 are similar to those of the domestic cat. These results show the evolutionary relationship between the leopard and domestic cat. The karyotype formula for the male and female leopard is as follows: 2n(38) = L2m + L4sm + L4a + M2m + M2sm + M4a + S6m + S8sm + S4t + sex chromosomes.

A Study on Karyotype of the Asian Leopard Cat, <i>Prionailurus bengalensis</i> (Carnivora, Felidae) by Conventional Staining, G-banding and High-resolution Technique

A karyotypic study of the Asian leopard cat (Prionailurus bengalensis) in Thailand has been made. Blood samples were taken from 2 males and 2 females. After the standard whole blood lymphocyte culture in the presence of colchicine, the metaphase spreads were performed on microscopic slides and air-dried. Conventional staining, G-banding and high-resolution techniques were applied to stain the chromosomes. The results showed that 2n of the Asian leopard cat was 38, and the fundamental number (NF) was 74 in male and female. There are 6 autosome types: A type has 4 large and 2 medium submetacentric chromosomes, B type has 6 large and 2 medium acrocentric chromosomes, C type has 4 large metacentric chromosomes, D type has 8 small submetacentric chromosomes, E type has 8 small metacentric chromosomes and F type are 2 small telocentric chromosomes. A pair of the short arm of chromosome E1 (chromosome pairs 14) showed a clearly observable satellite chromosomes. The X chromosome was medium submetacentric chromosome and the Y chromosome was the smallest metacentric chromosome. From the G-banding and high-resolution techniques, the number of bands and locations in the Asian leopard cat was 183 and 236 respectively, and each chromosome pair could be clearly differentiated. We found that chromosomes A1, A2, A3, B3, B4, C1, C2, D3, D4, E1, E3, F1 and X chromosome patterns were according to the domestic cat (Felis catus) chromosomes. Chromosomes B1, B2, D2 and E2 are similar to those of the domestic cat. These results show the evolutionary relationship between the Asian leopard cat and the domestic cat. The karyotype formula for the male and female Asian leopard cat is as follows:2n (38)=L4m+L4sm+L6a+M2sm+M2a+S8m+S8sm+St2+Sex-chromosome

B-chromosomes in two Brazilian populations of Dendropsophus nanus (Anura, Hylidae)

We report on the presence of B-chromosomes in two populations of Dendropsophus nanus (= Hyla nana Boulenger, 1889) from Sao Paulo State, Brazil. Such chromosomes were observed in 4 out of 43 specimens (9.3%) and in 9 out of 15 specimens (60%) from the municipalities of Nova Alianca and Botucatu, respectively. The karyotype 2n = 30 + 1B found in D. nanus was similar to that of other species with 2n = 30 chromosomes, except for the presence of an additional small telocentric chromosome. In one specimen from Botucatu, cells with one to three extra chromosomes were observed. These B-chromosomes appeared as univalent in meiosis I and did not bear a nucleolar organizer region or exhibit constitutive heterochromatin.