• Environmental Mutagens and Carcinogens
• /
• v.16 no.2
• /
• pp.103-108
• /
• 1996

The mutagenic potential of rHu-EPO was evaluated using the short-term genotoxicity tests including Ames, chromosome aberration and micronuclei tests. In Salmonella typhimurium assay, rHu-EPO did not show any mutagenic response in the absence or presence of S9 mix with TA98, TA100, TA1535, and TA1537. In chromosome aberration test, rHu-EPO did not show any significant effect on Chinese Hamster Ovary(CHO) cells compared with control. In micronucleus test using male ICR mice, a dose-dependence increase in the frequency of micronucleuted polychromatic erythrocytes(MNPCEs) was observed in bone marrow cells treated with rHu-EPO. However, it was related to the secondary effect of rHu-EPO and the number of MNPCEs was equal to spontaneous frequency. These results indicate that rHu-EPO does not show any positive response in short-term genotoxicity assays.

• The Korean Journal of Zoology
• /
• v.25 no.2
• /
• pp.81-92
• /
• 1982

G- and C-banding pattern analyses of striped field mice (Apodemus agrarius coreae) using 17 specimens from four localities in Korea revealed that centromeric heterochromatin results in the variation of No. 1 chromosome pair (telocentri $c_telocentric), i.e., centromeric heterochromatin sometimes appeared to be recognized as short arm. G- and C-banding patterns of four black rats (R. rattus rufescens) from two localities in Korea showed that No. 1 chromosome polymorphism (telocentri $c_telocentric) is due to pericentric inversion. In addition, G- and C-banding patterns of black rats mentioned above are idiogrammed.ammed.

• Clinical and Experimental Reproductive Medicine
• /
• v.12 no.2
• /
• pp.39-57
• /
• 1985

Presented in this paper the data from a chromosome study of 397 patients referred for suspected chromosmal abnormalities. Karyotypes were obtained using short-term blood culture and direct method. Of these 238 patients had normal chromosome complements; 159 (40.1%) patients had chromosome abnormality. Among all patients with chromosome abnormalities, 82.4% (131/159) had aberrations of chromosome number, the others 17.60/0 (28/159\ had aberrations of chromosome structure. Ten had a chromosome rearrangement; Five of them were reciprocal and five Robertsonian translocations. Four patients with pericentric inversions and one with paracentric inversions and four with isochromosomes were observed. There were four patients with marker chromosome, two patients had a chromosome insertion; and three others. (additional abnormal chromosomes.) Thus the results of the present study indicate the importance of cytogenetic evaluation in clinically abnormal patients.

• Journal of Plant Biology
• /
• v.21 no.1_4
• /
• pp.29-32
• /
• 1978

The karyotype of Lilium cernum has been analysed by means of C-banding technique. Most of clones observed were 2n=24 chromosomes which consist of two pairs of submetacentric and ten pairs of subtelocentric chromosomes, among which two pairs of chromosomes(B and E) showed secondary constriction in the short arm. In addition to these chromosomes a small supernumerary telocentric chromosome was seen in the eight clones. Sixtyeight bands were observed in the twentytwo chromosomes of complement and one band in the supernumerary chromosome. A pair of chromosome (L) did not show any band. The bnads on the chromosome. A pair of chromosome (L) did not show any band. The bands on the chromosomes were distributed in the centromere, secondary constriction and intercalary regions of arms. Of the twelve pairs of chromosomes ten pairs showed symmetric banding patterns in each, but two pairs (I and K) showed asymmetric banding patterns.

• Korean Journal of Plant Taxonomy
• /
• v.53 no.2
• /
• pp.166-169
• /
• 2023

Carex brevispicula (Cyperaceae) is endemic to Korea and is characterized by constricted achenes, short lateral spikes, and awned staminate and pistillate scales. The species classified in sect. Mitratae occurs throughout South Korea, perennating on mountains and/or rocky slopes under half shadow conditions. Meiotic chromosomes of the species were examined in this study, in which 33 meiotic cells from seven populations were found to be less than 2 ㎛ long with non-constricted chromosomes (n = 34_II). The stable chromosome number may be related to the narrow geographical distribution and/or distinct achene morphology. Further investigations of the distribution, morphological character variation, and chromosome characteristics should be conducted with closely related taxa to understand the derivation of the species and its endemism in Korea.

• Clinical and Experimental Pediatrics
• /
• v.46 no.5
• /
• pp.510-513
• /
• 2003

Duplication of chromosome 7q has been reported as either partial or complete. Partial 7q duplication was first described by Carpentier in 1972. Pure partial duplication of the long arm of chromosome 7 is extremely rare and only 16 cases with a pure partial duplication of different 7q segment have been described in the literature. Pure partial duplication of the long arm of chromosome 7 is characterized by growth and developmental retardation, muscular hypotonia, distinct craniofacial dysmorphic features, a short neck and skeletal abnormalities. A 3 month-old male was referred to our department of Pediatrics because of dyspnea, hypotonia and delayed development. He shows growth and developmental delay, hypertelorism, a depressed nasal bridge, low set ears, a short neck and muscular hypotonia. Karyotype revealed 46, XY, dup(7)(q36q33) by GTC-banding. We report a case of a partial inverted duplication of chromosome 7q.

• Korean Journal of Head & Neck Oncology
• /
• v.14 no.1
• /
• pp.20-26
• /
• 1998

Objectives: Deletion in the short arm of chromosome 3 is common in many human cancers, including sporadic and hereditary renal carcinomas, small cell lung carcinomas, non-small cell lung carcinomas, and carcinomas of the ovary, breast, and cervix. A high frequency of chromosomal aberrations in head and neck cancers involving chromosome 3p has also been reported. These findings suggest that multiple tumor suppressor genes may be present on the short arm of chromosome 3. Materials and Methods: To investigate the possibility of chromosome 3p deletions in the Korean head and neck cancer patients, we applied a polymerase chain reaction(PCR)-based Restriction Fragment Length Polymorphism analysis to the DNA samples of matched normal mucosa and head and neck squamous cell carcinomas from 19 patients. Results: In the 19 normal samples heterozygosity at the polymorphic loci varied: 6 at the D3F15S2 locus(on telomeric 3p21), 2 at the D3S32 locus(on centromeric 3p21), and 4 at the THRB locus(on centromeric 3p24). In 12 matched carcinoma specimens, LOH(loss of heterozygosity) was observed at D3F15S2 in 1 of 6(17%), D3S32 in 1 of 2(50%), and at THRB in 2 of 4 cases(50%). Conclusion: The frequency of chromosome 3p deletion in the Korean head and neck carcinomas appear as other country did.

• Journal of Microbiology and Biotechnology
• /
• v.17 no.7
• /
• pp.1079-1082
• /
• 2007

Chromosome microdissection and the reverse FISH technique is one of the most useful methods for the identification of structurally abnormal chromosomes. In particular, the laser microbeam microdissection (LMM) method allows rapid isolation of a target chromosome or a specific region of chromosomes without damage of genetic materials and contamination. Isolated chromosomes were directly amplified by the degenerate oligonucleotide-primed polymerase chain reaction (DOP-PCR), and then the FISH probes labeled with spectrum green- or spectrum red-dUTP were generated by nick-translation. Whole chromosome painting (WCP) probes were successfully generated from only 5 copies of the chromosome. With this method, we produced 24 WCP probes for each human chromosome. We also tried to characterize a marker chromosome, which seemed to be originated from chromosome 11 on conventional banding technique. The marker chromosomes were isolated by the LMM method and analyzed by reverse FISH. We elucidated that the marker chromosome was originated from the short arm of chromosome 5 ($5p11{\to}pter$). A fully automated and computer-controlled LMM method is a very simple laboratory procedure, and enables rapid and precise characterization of various chromosome abnormalities.

• Animal cells and systems
• /
• v.16 no.6
• /
• pp.438-446
• /
• 2012

In 1964, Susumu Ohno, an evolutionary biologist, hypothesized that the size of X chromosome was conserved in mammalian evolution, and that this was based on chromosomal length. Today, unlike Ohno's method which was based on estimated lengths, we know the exact lengths of some mammalian sequences. The aim of this study was to reanalyze Ohno's hypothesis. In mammalian species, variation in the length of the X chromosome is greater than in the autosomes; however, this variation is not statistically significant. This means that differences in chromosomal length occur equally in the X chromosome and in the autosomes. Interspersed nuclear elements and genetic rearrangements were analyzed to maintain the same variance between the length of the X chromosome and the autosomes. The X chromosome contained fewer short interspersed elements (SINEs) (0.90 on average); however, it did contain more long interspersed elements (LINEs) than did autosomes (1.56 on average). An overall correlation of LINEs and SINEs with genetic rearrangements was observed; however, synteny breaks were more closely associated with LINEs in the autosomes, and with SINEs in the X chromosome. These results suggest that the chromosome-specific activities of LINEs and SINEs result in the same variance between the lengths of the X chromosome and the autosomes. This is based on the function of interspersed nuclear elements, such as LINEs, which can inactivate the X chromosome and the reliance of non-autonomous SINEs on LINEs for transposition.

• Clinical and Experimental Pediatrics
• /
• v.48 no.1
• /
• pp.108-111
• /
• 2005

Ring chromosome 20 mosaicism [r(20)] is a rare chromosomal anomaly associated with minor dysmorphism, mental retardation, autistic behavior, and intractable epilepsy. The proposed mechanism of ring formation is breakage of both short and long arms of a chromosome with subsequent end-to-end fusion. We encountered an 18-month-old boy who presented with developmental delay and mental retardation with seizure episodes, but showed normal brain magnetic resonance imaging. Chromosome study from peripheral blood showed 46,XY, r(20)(p13q13.3) karyotype. The authors report a case of ring chromosome 20 with mental retardation and epilepsy, with a review of the literature.