• Korean Journal of Plant Taxonomy
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• v.42 no.4
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• pp.307-315
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• 2012

Somatic chromosome numbers for 10 taxa and karyotypes analysis for 6 taxa of Korean Vicia were investigated. Somatic chromosome numbers of treated taxa were 2n = 12, 14 or 24 and therefore they proved to be diploid or tetraploid with basic chromosome numbers of x = 6 or 7. The chromosome number of V. hirticalycina (2n = 2x = 12) was reported for the first time in this study. The chromosome numbers of nine taxa were the same as in previous studies; V. angustifolia (2n = 2x = 12), V. cracca (2n = 4x = 24), V. hirsuta (2n = 2x = 14), V. tetrasperma (2n = 2x = 14 + 2B), V. amurensis (2n = 2x = 12), V. chosenensis (2n = 2x = 12, 12 + 2B), V. unijuga (2n = 4x = 24), V. unijuga f. minor (2n = 4x = 24), V. venosa var. cuspidata (2n = 4x = 24). The karyotypes of V. cracca, V. amurensis, V. hirticalycina, V. unijuga, V. unijuga f. minor, V. venosa var. cuspidata were observed as 2 m + 8 sm + 2 st, 2 m + 2 sm + 2 st, 3 m + 1 sm + 2 st, 4 m + 6 sm + 2 st, 4 m + 6 sm + 2 st, 4 m + 8 sm, respectively.

• Journal of Environmental Health Sciences
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• v.16 no.1
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• pp.55-65
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• 1990

This study was carried out to investigate the effects on sister chromatid exchanges (SCEs) and chromosome aberrations in PHA or LPS stimulated mouse spleen and bone marrow lymphocytes after an acute whole body irradiation. Frequencies of sister chromatid exchanges were significantly increased with the increased dose(from zero to 400tad) but there was no differences between B-cell and T-cell. By times, the maximum induced SCE levels was observed at 12 hours after irradiation and then returned to base level at one day in 100rad group and three day in 400rad group. There was a significant difference in chromosome aberration with increasing exposure. X-ray irradiated chromosome aberration was long lived relative to SCE. This results show that counting the incidence of SCE may not provide a sensitive system for detecting X-ray exposure.

• Journal of Life Science
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• v.13 no.6
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• pp.958-969
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• 2003

The human Y chromosome is strictly paternally inherited and does not X-Y crossing over during male meiosis in most of its length. Although this region came to be known as the non-recombining region Y (NRY), it was renamed as male-specific region Y (MSY) due to abundant recombination. The MSY is a mosaic of heterochromatic sequences and three classes of euchromatic sequences: X-transposed, X-degenerated and ampliconic. The X-transposed sequences exhibit 99% identity to the X chromosomal sequences. The X-degenerate sequences are remnants of ancient autosomes from which the modem X and Y chromosomes evolved. Eight palindromes of the ampliconic comprise one-quarter of the euchromatic DNA of the male-specific region of the human Y chromosome. They contain many testis-specific genes and typically exhibit 99.97% intra-palindromic (arm-to-arm) sequence identity. The arms of these palindromes must have subsequently engaged in gene conversion, driving the pair arms to evolve it concert. Averages of approximately 600 nucleotides per newborn male have undergone Y-Y gene conversion, which has had an important role in the evolution of multi-copy testis gene families in the MSY.

• Journal of Photoscience
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• v.12 no.2
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• pp.75-82
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• 2005

Rumex acetosa L. is a dioecious flowering plant with well developed sex chromosome system: 2n = 12 + XX in the female plants and 2n = 12 + XY1Y2 in the male plants. To isolate sex-linked DNA, we carried out chromosome micromanipulation, followed by DOP-PCR, AFLP of the PCR products, reverse Southern hybridization and sequence analysis. From 500 AFLP specific clones, 13 X-chromosome and 5 Y-chromosome specific clones were obtained. Except one clone RADAX-239 ($\underline{R}umex\;\underline{a}-\underline{D}OP-PCR-\underline{A}FLP-\underline{Y}-chromosome\;specific$), all clones appear to be R. acetosa plant-specific sequences and non-coding sequences. Southern blot analysis using these clones could not discriminate genomic DNAs either from male or female plants. Results of this study imply that both autosome-origin and degeneration of sex chromosomes are prevalent in plant systems.

• Journal of Radiation Protection and Research
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• v.29 no.4
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• pp.243-249
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• 2004

The cytokinesis-block micronucleus (CBMN) assay in combination with FISH technique using chromosome-specific centromeric probes for chromosome 1 and 4 was performed in mitogen stimulated human lymphocytes which were exposed to x-radiation to identify different sensitivity of chromosomes to the induction of micronuclei(MN) and aneuploidy by radiation. The frequencies of micronucleated cytokinesis-blocked(MNCB) cells and MN in binucleated lymphocytes(BN) increased with the increase in radiation dose. A significant induction of aneuploidy of chromosome 1 and 4 were found. The frequency of aneuploidy of chromosome 1 and 4 in the control were 9 per 2,000 BN cells and this increased to 47 and 71 following irradiation at a dose of 1 and 2 Gy, respectively. The induction of aneuploidy of chromosome 1 was higher than that of chromosome 4. The frequency of aneuploid BN cells with MN exhibiting positive centromere signal for either chromosome 1 and/or 4 increased in a dose dependent manner, and that for chromosome 1 is higher than that for chromosome 4. Among the total induced MN in irradiated lymphocytes, smaller proportion of MN exhibit centromeric signal of chromosome indicating that radiation-induced MN are mainly originated from chromosomal breakage rather than chromosomal non-disjunction. These results suggest that x-radiation can induce aneuploidy and supports the finding that chromosome vary in their sensitivity to aneuploidy induction by x-irradiation.

• Korean Journal of Plant Taxonomy
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• v.39 no.1
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• pp.42-47
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• 2009

In this study, the somatic chromosome of 14 taxa of Korean Galium L. were investigated. Among them were a few taxa for which the somatic chromosome number was determined for the first time. The somatic chromosome numbers of Korean Galium L. were 2n = 22, 24, 44, 48, 66, 72, 77, 88 and so basic chromosome numbers were x = 11 or 12. Those taxa having the basic chromosome number x = 11 showed polyploidy, including diploid, tetraploid, heptaploid, and octoploid. Tetraploid and hexaploid can be observed in those taxa with the basic number x = 12. The eleven taxa reported 11 for the first time are G. spurium var. echinospermon (Wallr.) Hayek (2n = 44), G. gracilens (A. Gray) Makino (2n = 22), G. pogonanthum Franch. & Sav. (2n = 22, 44), G. trachyspermum A. Gray (2n = 22, 44), G. japonicum (Maxim.) Makino & Nakai (2n = 77), G. trifloriforme Kom. (2n = 44), G. dahuricum Turcz. var. dahuricum (2n = 48, 72), G. dahuricum var. tokyoense (Makino) Cufod. (2n = 22), G. kinuta Nakai & Hara (2n=66), G. verum var. trachycarpum for. nikkoense (Nakai) Ohwi (2n = 44), G. verum var. asiaticum for. pusillum (Nakai) M. Park (2n = 44). The taxa with the same chromosome numbers as previously reported ones were G. boreale L. (2n=22) and G. verum var. asiaticum Nakai for. asiaticum (2n = 44). The chromosome number of G. trifidum L. (2n = 22) was different from the previous report. Two infraspecific taxa of G. dahuricum showed differences in their basic chromosome numbers (x = 11 for G. dahuricum Turcz. var. dahuricum and x = 12 for var. tokyoense (Makino) Cufod. The somatic chromosome number for G. dahuricum Turcz. var. dahuricum was found to be 2n = 48 (tetraploid) or 72 (hexaploid), while that of G. dahuricum var. tokyoense (Makino) Cufod. was found to be 2n = 22 (diploid). Therefore, basic chromosome numbers for members of the genus Galium can be used as valuable characters in delimiting infrageneric sections and investigating interspecific relationships.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.9
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• pp.1378-1386
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• 2020

Objective: Chinese indigenous sheep breeds can be classified into the following three categories by their tail morphology: fat-tailed, fat-rumped and thin-tailed sheep. The typical sheep breeds corresponding to fat-tailed, fat-rumped, and thin-tailed sheep are large-tailed Han, Altay, and Tibetan sheep, respectively. Detection of copy number variation (CNV) and selection signatures provides information on the genetic mechanisms underlying the phenotypic differences of the different sheep types. Methods: In this study, PennCNV software and F-statistics (F_ST) were implemented to detect CNV and selection signatures, respectively, on the X chromosome in three Chinese indigenous sheep breeds using ovine high-density 600K single nucleotide polymorphism arrays. Results: In large-tailed Han, Altay, and Tibetan sheep, respectively, a total of six, four and 22 CNV regions (CNVRs) with lengths of 1.23, 0.93, and 7.02 Mb were identified on the X chromosome. In addition, 49, 34, and 55 candidate selection regions with respective lengths of 27.49, 16.47, and 25.42 Mb were identified in large-tailed Han, Altay, and Tibetan sheep, respectively. The bioinformatics analysis results indicated several genes in these regions were associated with fat, including dehydrogenase/reductase X-linked, calcium voltage-gated channel subunit alpha1 F, and patatin like phospholipase domain containing 4. In addition, three other genes were identified from this analysis: the family with sequence similarity 58 member A gene was associated with energy metabolism, the serine/arginine-rich protein specific kinase 3 gene was associated with skeletal muscle development, and the interleukin 2 receptor subunit gamma gene was associated with the immune system. Conclusion: The results of this study indicated CNVRs and selection regions on the X chromosome of Chinese indigenous sheep contained several genes associated with various heritable traits.

• Korean Journal of Plant Taxonomy
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• v.41 no.4
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• pp.324-328
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• 2011

The purpose of this study was to analyze the interspecific relationships of Chenopodium album and its related taxa collected in Korea. The 18S-26S ribosomal DNA (45S rDNA) loci were detected directly on mitotic chromosomes by fluorescence in situ hybridization (FISH) and the chromosome numbers were examined using aceto-orcein methods. The chromosomal numbers of Chenopodium album var. album and C. album var. centrorubrum were 2n = 6x = 54, whereas for C. album var. stenophyllum, this number was 2n = 4x = 36. The basic chromosome number was x = 9. The biotin labeled 18S-26S rDNA probe exhibited eight yellow fluorescent signals on the metaphase chromosome of C. album var. album and var. centrorubrum respectively, while two yellow signals of C. album var. stenophyllum were noted. All of the signals on the chromosomes were located at the terminal regions. The chromosome number and FISH findings suggest that C. album var. centrorubrum is merged into var. album and that it is clearly distinguished from C. album var. stenophyllum.

• Biomedical Science Letters
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• v.25 no.2
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• pp.113-122
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• 2019

Long-non coding RNAs (LncRNAs) constitute a wide and extremely diverse family of RNA transcripts that are greater than 200 base pairs in length and are not translated into proteins. X-inactive specific transcript (XIST) was the first long non-coding RNA to be discovered, back in 1991. Its function in X-chromosome inactivation has been extensively studied for three decades, though other functional roles of XIST that involve a variety of fascinating mechanisms remain to be elucidated. Here, we review the emerging oncogenic role of XIST in various human cancers.

• Journal of Genetic Medicine
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• v.3 no.1
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• pp.21-24
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• 1999

To study the X chromesome mosaicism in the cytogenetically pure 45,X Turner syndrome patients, we applied PCR technique using DNAs extracted from archived cytogenetic slides. We amplified the DNAs using nested primers targeted to a highly polymorphic short tandem repeat(STR) of the human androgen receptor gene(HUMARA) for the detection of X chromosome mosaicism. This assay is a very sensitive and useful method which can be applied to the DNAs extracted from archived cytogenetic slides to detect X mosaicism. We have tested 50 normal Korean females to determine whether the HUMARA locus is highly polymorphic among Koreans. 85% of Korean population showed heterozygosity in the HUMARA locus. We analysed the 24 DNAs extracted from archived slides of patients and abortuses with Turner syndrome in cytogenetic analysis. We observed the heterozygosities of 50% from pure 45,X patients, 83% from the patients with mosaic Turner syndrome and 8.3% from the abortuses of pure 45,X. Using the PCR technique of the HUMARA locus in the archived cytogenetic slides, we detected X chromosome mosaicism which could not be detected in cytogenetic analysis.