The karyotype of Korean short-hair cat was presented using the G-, C- and NOR- banding techniques. For chromosomes preparation, the fetus skin fibroblast cells were cultured and metaphases were obtained. In results, the Korean short-hair cat had 38 chromosomes with XX or XY, which consisted of 5 pairs of metacentric chromosomes(Group A and C), 3 pairs of submetacentric chromosomes (Group B), 6 pairs of medium metacentric chromosomes except for 1 pair of medium submetacentric D2 chromosomes (Group D, E), 2 pairs of acrocentric chromosomes(Group F) and metacentric X and Y sex chromosomes. In G-banding analysis, the Korean short-hair cat exhibited a typical and identical G-banding pattern in each homologous chromosome. Total number of bands and landmarks on the G-banded chromosomes of Korean short-hair cat well correspond to those of international standardization of karyotype of domestic cat. The heterochromatins of Korean short-hair cat chromosomes distributed at terminal and/or centromere regions on almost chromosomes by C-banding analysis. In addition, the C-banding pattern showed greatly heteromorphic in some chromosomes. Using the AgNOR-staining, we found the nucleolar organizer regions(NORs) of Korean short-hair cat located at chromosomes 1p12 site in E group. The quantity and number of NORs were constant among cells.

Fluorescence in situ hybridization (FISH) is a powerful tool for the detection of DNA sequences in the specific region of the chromosomes. As well as for the integrated physical mapping, FISH karyotype analysis has to be preceded. The detailed karyotypes of two onion cultivars, which are resources for onion genome sequencing project (‘Eumginara’ and ‘Sinsunhwang’), were constructed based on triple color fluorescence in situ hybridization (FISH) using 5S rDNA, 45S rDNA, and tandem repeat sequence. All used our materials showed 2n=2x=16 with x=8 as basic chromosome number. 5S rDNAs were located on 4 loci in one pair of interstitial region of short arm chromosome in both onion cultivars. Two pairs of 45S rDNAs were positioned in distal region of short arm chromosome in ‘Eumginara’. Otherwise 5 loci of 45S rDNAs were located in distal region of two pairs of short arm chromosome in ‘Sinsunhwang’. Among them, two signals of 45S rDNAs were co-localized in distal part of short arm and long arm chromosome, respectively. In case of tandem repeat sequence was detected on telomeric region of 8 pairs of chromosomes except on 45S ribosomal DNA sites. These results will provide a valuable background for physical mapping and help to further more understand the genome sequencing project in Allium cepa.

Analyses of now karyotypes using different maize (Zea mays L.) inbred lines have been performed. The accumulation and isolation of high quality and quantity metaphase chromosomes from root tips can be achieved from many kinds of maize lines. The chromosome suspensions were prepared by a simple slicing method from synchronized maize root tips and analyzed with a now cytometry. The variations of experimental now karyotypes were detected among inbred lines in terms of the positions and/or the numbers of chromosome peaks. The 2C DNA amount among 8 inbred lines ranged from 5.09 to 5.52 pg. The variability of DNA content in maize chromosome 1 was 9.1 % ranging from 0.685 to 0.747 pg. The selection of appropriate maize lines is critical for sorting specific single chromosome types. At least five different chromosome types can be discriminated and sorted from five maize lines.