• The Korean Journal of Zoology
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• v.7 no.2
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• pp.13-18
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• 1964

The chromosomes of thirteen wild forms of Drosophila obtained from Kwangnung in Kyunggi Province, Korea were investigated with the ganglion cells of both male and female larvae using the aceto-lactic orcein squashed method. The male chromosome patterns of the species observed in the present study are summarized as follows:

• Journal of Aquaculture
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• v.3 no.2
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• pp.145-153
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• 1990

Genetic analysis of rainbow trout populations in hatchery stocks is important in order to develop a strategy for their management. In this study, chromosome number and polymorphisms of diploid and artificially induced triploid rainbow trout are discribed. The relation-ship between chromosomal polymorphism and their economic values for the aquaculture industry are also discussed.

• The Korean Journal of Malacology
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• v.12 no.1
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• pp.33-38
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• 1996

강원도 동해안에서 채집된 백합과 1종, 대복의 염색체수와 핵형을 분석하였다. 대복의 염색체수는 2n=38이며, 핵형의 구성은 3쌍의 metacentric과 16쌍의 submetacentric염색체로 구성되었다.

• Korean Journal of Plant Taxonomy
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• v.40 no.3
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• pp.153-156
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• 2010

The somatic chromosome number of four Korean species of Leontopodium were investigated. The chromosome number of L. leiolepis (2n = 24) is reported here as for the first time. The chromosome number of L. japonicum (2n = 28) is not varied among the 3 populations on the Korean Peninsula, but that condition is different from the previous reports for Korea (2n = 26) and Japan (2n = 21, 26). L. hallaisanense and L. japonicum, both of which are in sect. Nobilia and similar to each other in gross morphology, have the same chromosome number of 2n = 28. On the other hand the chromosome number of Korean L. leontopodioides (2n = 24) is different from that in Russian reports (2n = 26). The chromosome numbers of all Korean species of the genus Leontopodium could be inferred as tetraploid or aneuploid.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.4
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• pp.310-318
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• 1991

This experiment was carried out to obtain the information on the variation of chromosome number in pollen mother cell (PMC) and somatic cell of the progeny from the cross between hexaploid triticale cv. Sinkihomil and five hexaploid wheat varieties. The results were summarized as follows: Number of uni-, bi- and tri-valent in PMC was 11.9, 14.4 and 0.44, respectively, in the F$_1$ between triticale and wheat. Significant positive correlation between the pollen fertility and seed set rate, pollen fertility and bivalent number of PMC, and seed set rate and bivalent number of PMC, and negative correlation between pollen fertility and uni-or tri-valent of PMC in the cross between triticale and wheat were detected. F$_1$ (crossed seed) had 42 chromosomes, F$_2$ and F$_1$/P$_1$ showed high frequency of hyperploid (42-49) and F$_1$/P$_2$ showed high frequency of hypoploid (36- 42), which suggest non-random segregation for somatic chromosome number. in the cross between the triticale and wheat.

• Korean Journal of Poultry Science
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• v.13 no.2
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• pp.167-172
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• 1986

Chromosome size, number and shape were studied by the centromeric index, the arm ratio and the relative length of chromosome. The chromosomes of 50 early chick embryos which were derived from a pure line of Single Comb White Leghorns were examined. Using a colchicine, hypotonic treatment, fixation and air-drying technique, the clear prometaphase figures were obtained from the whole embryo. The results of the present investigation of chromosome pairs were as follows, 1. Pair 1 and 2; metacentric and submetacentric chromosomes which could be clearly distinguished from each other by size. 2. Pair 3 and 4: acrocentric chromosomes of similar length but the 4th pair had a distinct short arm which was not present in the 3rd. 3, Pair 5; metacentric sex chromosomes, 2 chromosome had relative 5th length but the W chromosome had slightly shorter length than 7th pair of chromosomes. 4. Pair 6; acrocentric chromosomes similar in shape to pair 3 but of little more than half the size. 5, Pair 7 and 8; acrocentric chrocentric but the 7th pairs had a definite short arm. 6. Pair 9; similar length to the 7, 8 pairs but had a medially placed centromere. 7. microchromosomes of 30 pairs ; nearly all acrocentric chromosomes which appeared as paired dots. The total number of diploid was appeared to 72-78. But a number of observations presented the total diploid number in 78 (58%). The inconstancy in number observed in this study was presumably due to the minute size of the microchromosomes. Thus, the modal numbers for the diploid chromosome was at least 78.

• Korean Journal of Ichthyology
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• v.2 no.2
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• pp.211-216
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• 1990

Mitotic analyses of the coho salmon (Oncorhynchus kitsuch) revealed a mode of 2n=60 whit 46 meta or submetacentric and 14 acrocentric chromosomes (NF=106). Individuals with 2n=61 were also found in both sexes in the same population; the karyotype is composed of 45 meta or submetacentric and 16 acrocentric chromosomes (NF=106). This result may indicate that Robertsonian chromosomal polymorphism occurred in the population of the coho salmon.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2002.11a
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• pp.105-105
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• 2002

염색체의 구조적 이상으로 인한 습관성 유산과 기형아의 출산을 예방하기 위해 착상전 배아에서 할구를 분석하여 정상적인 핵형을 가진 배아만을 이식하는 착상전 유전자 진단 (preimplantation genetic diagnosis, PGD)의 성공적인 임상 적용이 보고되고 있으며, 그 적용 범위가 확대되고 있다. 그러나 일반적인 간기의 핵상을 이용한 PGD에서는 형광직접보합법 probe의 제약으로 보인자와 정상적인 핵형을 구분할 수 없는 단점이 있다. 따라서 본 연구에서는 보다 정확한 PGD를 위해 생쥐 배아를 이용하여 분리한 할구에서 중기 염색체상을 획득하기 위해 미세소관 (microtubule) 형성 저해제를 처리하였으며, 이를 통해 확립된 방법을 인간의 PGD에 적용하고자 하였다. 과배란이 유도된 ICR 생쥐에서 4- 또는 8-세포기 배아를 수획하여 colcemid, nocodazole, vinblastine을 각각 0.1, 0.5, 1.0, 5.0$\mu$M을 처리하고, hoechst 33342로 염색하여 핵상을 관찰하여 최적의 농도를 결정하였다. 또한 각 미세소관 형성 저해제를 혼합 처리하여 가장 높은 중기 염색체상을 획득할 수 있는 혼합 처리를 결정하였다. 이렇게 결정된 혼합 처리 방법을 인간의 체외 수정 및 배아 이식술에서 획득된 3PN 배아에 처리하여 중기 염색체를 획득하였다. Colcemid, nocodazole, vinblastine 모두 1 $\mu$M이 최적 농도임을 확인할 수 있었다 (각각 96.3%, 92.0%, 98,4%). 미세소관 형성저해제를 혼합 처리하였을 경우 nocodazole과 vinblastine (각각 1$\mu$M)을 혼합 처리했을 때 중기 염색체 획득률(97.3%)이 가장 높았다. 인간의 3PN 배아에 1$\mu$M의 nocodazole과 vinblastine을 혼합 처리한 후, 113개의 할구를 분석하여 44개(38.9%)의 할구에서 중기 염색체를 확인할 수 있었다. 본 실험 결과를 통해 중기 염색체를 획득하기 위하여 미세소관 형성 저해제를 처리하는 방법은 생쥐의 배아에서는 효과적이지만, 인간의 배아에서는 그 효율이 다소 낮음을 알 수 있었다. 그러나 이 방법을 개선하여 인간의 할구에서 중기 염색체의 획득률을 높이고, 이를 염색체의 구조적 이상에 대한 착상전 유전자 진단에 적용한다면, 보인자와 정상의 핵상을 구분하여 정상의 핵상만을 갖는 배아의 이식을 통하여 더욱 정확한 착상전 유전자 진단을 시행할 수 있으리라 사료된다.

• Journal of Genetic Medicine
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• v.7 no.2
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• pp.111-118
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• 2010

Chromosomal microarray analysis (CMA) enables the genome-wide detection of submicroscopic chromosomal imbalances with greater precision and accuracy. In most other countries, CMA is now a commonly used clinical diagnostic test, replacing conventional cytogenetics or targeted detection such as FISH or PCR-based methods. Recently, some consensus statements have proposed utilization of CMA as a first-line test in patients with multiple congenital anomalies not specific to a well-delineated genetic syndrome, developmental delay/intellectual disability, or autism spectrum disorders. CMA can be used as an adjunct to conventional cytogenetics to identify chromosomal abnormalities observed in G-banding analysis in constitutional or acquired cases, leading to a more accurate and comprehensive assessment of chromosomal aberrations. Although CMA has distinct advantages, there are several limitations, including its inability to detect balanced chromosomal rearrangements and low-level mosaicism, its interpretation of copy number variants of uncertain clinical significance, and significantly higher costs. For these reasons, CMA is not currently a replacement for conventional cytogenetics in prenatal diagnosis. In clinical applications of CMA, knowledge and experience based on genetics and cytogenetics are required for data analysis and interpretation, and appropriate follow-up with genetic counseling is recommended.

• Korean Journal of Plant Taxonomy
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• v.38 no.2
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• pp.151-162
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• 2008

Chromosome analysis using karyotyping and bicolor FISH were carried out in Pimpinella hallaisanensis which is one of the endemic plants in Jeju island of Korea. The somatic methaphase chromosomes number of this plant was 2n=2x=22 and the size of this chromosomes ranged from 3.58 to $5.82{\mu}m$. The chromosome complements consisted of two pairs of metacentrics (chromosomes 1 and 2), four pairs of submetacentrics (chromosomes 3, 4, 6 and 8) and five pairs of subtelocentrics (chromosomes 5, 7, 9, 10 and 11). Using bicolor FISH, three pairs of 5S and four pairs of 45S rDNA loci were observed. Two pairs of 5S rDNA signals were detected on the end of the long arm of chromosome 4 and one pair of them were observed between long arm end and centromere. Another 45S rDNA signals were detected on the end of short arm of chromosome 4, 6, 10 and 11, respectively. Hence, the chromosome number reexamined using both conventional staining and FISH methods was different from previous report.