• Journal of Genetic Medicine
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• v.8 no.1
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• pp.44-52
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• 2011

Purpose: Cytogenetic analysis of spontaneous abortions (SABs) provides valuable information to establish the causes of fetal loss, information that is essential to provide accurate reproductive and genetic counseling couples. Such analysis also provides information on the frequencies and types of chromosomal abnormalities and associated risks of recurrence. However, there have only been a few reports of chromosomal abnormalities in small samples of SABs in the Korean population. Here, we report the incidence and spectrum of chromosomal abnormalities for cases of 470 SAB in Korea. Material and Methods: Between 2005 and 2010, a total of 470 products of conception (POC) resulting from SABs were submitted to our laboratory for cytogenetic analysis from various medical sites in Korea. The incidences and types of specific chromosomal abnormalities were determined. The abnormalities were distinguished by gestational age at the time of SAB and by maternal age. Results: The frequency of chromosomal abnormalities in POCs was 54.3% (255/470), including 228 (89.3%) numerical and 27 (10.7%: 3 balanced and 24 unbalanced) structural abnormalities. Among the numerical abnormalities, trisomy was predominant (67.0%), followed by monosomy X (12.5%), polyploidy (8.2%), triple X (0.8%), and autosomal monosomy (0.8%). The overall sex ratio (male: female) among the 470 POCs with normal and abnormal karyotypes were 0.58 and 0.65, respectively. Trisomies were identified for each autosome, with the exceptions of 1, 3, and 19. Among the 171 autosomal trisomies, trisomy 16 was the most common (19.9%), followed by trisomy 22 (13.5%), trisomy 21 (12.3 %), trisomy 15 (9.9%), and trisomies 18 and 13 (5.3%). The frequency of chromosomal abnormalities decreased with gestational age and increased with maternal age, but only because of increases in trisomies and complex abnormalities. Conclusions: We have presented a large collection of cytogenetic data for SABs collected during the past 6 years and provided a database for prenatal genetic counseling of parents who have experienced SABs in Korea.

• Parasites, Hosts and Diseases
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• v.30 no.3
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• pp.183-190
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• 1992

Molecular karyotyping was applied to Pneumocystis carinii (Pc) from two strains of experimental rats, Sprague Dawley(SD) and Fisher(F), in Korea. Field inversion gel electrophoresis and contour clamped homogeneous electric field electrophoresis resolved 15 chromosomal bands from the Pc. The size of the bands was estimated 270kb to 684kb from SD rats, and 273kb to 713 kb from F rats. The bands of 283 kb from SD rats and of 273 kb from F rats stained more brightly suggesting duplicated bands. Total number of chromosomes was at least 16, and total genomic size was estimated 7×106 bp. All of the bands from F rats hybridized to the probe of repeated DNA sequences of Pc and the band of 448 kb size was proved to contain rDNA sequences, but Pc. chromosome bands from SD rats showed no reactions to the probes. The 2 different karyotypes of p. carinii from 2 strains of rats were maintained consistently for 2 years.

• Korean Journal of Medicinal Crop Science
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• v.11 no.5
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• pp.402-407
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• 2003

Karyotype analysis and chromosomal localization of 5S and 45S rDNAs using multi-color fluorescence in situ hybridization (McFISH) technique were carried out in Bupleurum longeradiatum. Somatic metaphase chromosome number was 2n=12. Karyotype was composed of three pairs of metacentrics (No.3, 4 and 6) and three pairs of submetacentrics (No. 1, 2 and 5). The length of somatic prometaphase chromosomes ranges from 2.55 to $5.05{\mu}m$ with total length of $18.15\;{\mu}m$. In FISH experiment, one pair of 5S rDNA signals was detected on the pericentromeric region of chromosome 4 and one pair of 45S rDNA signals was detected on the telomeric region of chromosome 2.

• Journal of Life Science
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• v.12 no.5
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• pp.605-609
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• 2002

None of the numerous published canine idiograms and karyotypes has yet been generally accepted as a standard one because the dog has 76 acrocentric autosomes of similar size and shape. To establish canine banded karyotype from the 22nd chromosome to the 37th chromosome, we analyzed canine chromosomes by GTG, high resolution, and NOR-banding techniques. The GTG and high resolution banding patterns of canine chromosomes corresponded to other reports described previously except for a few chromosomes. While other researchers observed 12 bands, we observed 7 bands in the banding patterns of chromosome 24, 34 and 37. On the other hand, the banding patterns by NOR-banding technique showed that three pairs of autosomes have nucleolus organizer regions at the terminal ends of their long arm, and the Y chromosome has it in its short arm terminal. However, the X chromosome has no nucleolus organizer like other mammals.

• The Korean Journal of Zoology
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• v.33 no.2
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• pp.222-230
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• 1990

The karyotypes of Korean Sciunis vulgaris coreas and Tamias sibiricus asiaticus were analyzed by conventional Giemsa staining and C-banding method. The diploid chromosome number (2n) of Sciunis vulgaris coreae 40 consisting of 6 metacentric, 8 submetacentric, 3 subtelocentric and 2 telocentric autosome pairs, submetacentric X and acrocentric or subtelocentric Y chromosome. The arm number (NF) of this species was obtained as 72, excluding the gonosomal arms. Tamias sibiricus asiaticus has a 2n of 38. The karyotype was represented by 3 metacentric, 4 submetacentric, 5 subtelocentric and 6 telocentric autosome paits and 2 sex chromosome. The X chromosome was submetacentric chromosome and the Y was the smallest chromosome with a median. The NF was 60. In S. vulgaris coreae constitutive heterochromatins were observed at the centromeres and telomeres. Constitutive heterochnomatins of T sibiricus asiaticus were primarily observed at the centromeres. These results suggested that non-Robensonian reanagenents and distribution of constitutive heterochromatin played an imporiant role in karyological differentiation of these species.

• Journal of Life Science
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• v.17 no.6 s.86
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• pp.762-765
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• 2007

A Giemsa C-banding method was used for the identification of somatic chromosomes and heterochromatic knob position in Korean indigenous waxy com (Zea mays L.). 5 inbred stocks were examined and their heterochromatic knob numbers ranged from 6 to 12. In comparison of homologous chromosomes of two stocks of YS-1 and MY-1, knob numbers, knob positions, arm ratios and relative length of chromosomes were different between the genotypes. The length of homologous chromosomes in YS-1 were generally larger than those of MY-1. The Giemsa method was proved to be useful for the identification of somatic chromosome and a C-banded diagram showing knob positions, arm ratios and relative length of chromosome could be used as a good tool to compare the characteristics of chromosomes of Korean indigenous waxy corn stocks.

• Microbiology and Biotechnology Letters
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• v.50 no.3
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• pp.436-440
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• 2022

In this study, yeast artificial chromosome Insert (YAC) harboring genes which related xylan metabolism was constructed by using chromosome manipulation technique. For efficient chromosome manipulation, each splitting fragment (DNA module) required for splitting process was prepared and these DNA modules were transformed into Saccharomyces cerevisiae strain YKY164. By two-rounds chromosome splitting, yeast chromosome VII (1,124 kb) was split 887 kb-YAC, 45 kb-mini YAC and 198 kb-YAC and YKY183 strain containing 18 chromosomes was constructed. Splitting efficiency for chromosome manipulation was 50- 78% and expression level of foreign genes on 45 kb-mini YAC and enzyme activity were indistinguishable from that of the YKY164 strain. Furthermore, xylan-degraded products by recombinant enzymes were confirmed and mini-yeast artificial chromosome maintained stable mitotic stability without chromosome loss during 160 generations.

• Korean Journal of Poultry Science
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• v.17 no.4
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• pp.275-280
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• 1990

Comosomal polymorphism involving constitutive heterochromatin has been reported in mu, pigs, mouse, horse, chicken and so on. The chromosomal polymorphism of Japanese quail which includes constitutive heterochromatin as well the chromosomes without banding treatment has now been found. Through the use of a general technique that permits visualization of chromosome morphology and heterochromatin, three chromosomal variants have been found among birds ； ＋/＋ homozygous from, ＋/－ heterozygous form and －/－ homozygous form in chromosome 4. This variants appear to be common in the randombred population and stably inherited in a Mendelian fashion. These results suggest that the variants would be useful as chromosomal markers for various types of cytogenetic studies.

• Journal of Animal Science and Technology
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• v.51 no.5
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• pp.361-368
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• 2009

This study was carried out to establish the standard karyotype of Jeju horse by G-, C- and AgNOR-banding patterns. Blood samples were collected from 37 Jeju horses and 24 Thoroughbred that had been raised at the National Institute of Subtropical Agriculture in Jeju. The lymphocytes were cultured in vitro and then chromosomes prepared. The diploid chromosome number of Jeju horse is 64, which consists of 31 pairs of autosomes and X, Y sex chromosomes. The Jeju horse has 13 pairs of metacentric/submetacentric and 18 pairs of acrocentric autosomes. The X chromosome is the fifth largest submetacentric, while the Y chromosome is one of the smallest acrocentric chromosomes. The G-banding pattern of Jeju horse chromosomes showed a light band at centromeres in all autosomes, and also exhibited a typical and identical banding pattern in each homologous chromosome. Overall chromosomal morphology and positions of typical landmarks of the Jeju horse were virtually identical to those of International Committee for the Standardization of the Domestic Horse Karyotype. C-bands of Jeju horse chromosomes appeared on centromeres of almost all autosomes, but chromosome 8 showed a heterochromatin heteromorphism. The NORs in Jeju horse chromosomes showed polymorphic patterns within breed, individuals and cells. By the AgNOR staining, the NORs were located at the terminal of p-arm on chromosome 1 and near centromeres on the chromosome 26 and 31. The mean number of NORs per metaphase was 4.68 in Jeju horse.

• Journal of Animal Science and Technology
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• v.46 no.4
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• pp.547-554
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• 2004

Telomeres are nucleoprotein structures at the ends of chromosomes consisting of tandem repeat sequences of . (TTAGGG)n. Telomeres serve as guardians of the genome, protect individual chromosomes within the nucleus, and help in meiotic pairing of homologous chromosomes. To investigate the telomere distributions of cattle and pig chromosomes, fluorescence in situ hybridization(FISH) was carried out on metaphase spreads of in vitro fibroblast cultures from Holstein and Landrace using a human telomeric DNA repeat probe. Results indicate that the distinct double spots on both ends of chromosomes of cattle and pigs were observed. In cattle, there was a random variation in the intensity of telomere signals among chromosomes. In pigs, an interstitial telomeric signal was observed on the chromosome 6q1 of all the cells examined. According to quantitative fluorescence in situ hybridization(Q-FISH) analysis, some chromosomes had consistently much more telorneres at one end of chromosomes. In general, both species had consistently much more telomeres at q-end than p-end on most of chromosomes. The relative amount of telomeres on bovine chromosomes was higher than that on pig chromosomes. In additions, Y chromosome had the highest relative amount of telorneres in cattle and pigs.