• Journal of Environmental Science International
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• v.7 no.5
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• pp.599-605
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• 1998

The purpose of this work was to examine whether X-Y chromosome dissociation in the primary spermatocytes of mice could be used as an in vivo short-term assaying system that detect environmental mutagens. Four alkylating agents(EMS, MMS, MMC and MNNG) which were known as strong mutagens were administered to BALB/c male mice 3-4 months old. In the control group, the mean frequencies of previously dissociated X and Y chromosomes and autosomes were 7.17% and 2.12%, respectively. Compared to the control group, mutagen-treated groups have no significant differences in dissociation rate of autosomes, while these poops were about 1.2-2.5 times higher in the frequencies of X-Y dissociation. Generally, X-Y dissociation frequency increased consistently with the concentration of mutagens whereas the tendency of autosome dissociation frequency was variable among several mutagens. These results suggest that X-Y dissociation in the primary spermatocytes of mice is applicable as an vivo short-term assaying system for environmental mutagens. There were significantly distinct increase in dissociation of X-Y chromosome in both the hybrid and parents but the X-Y previous dissociation of hybrid appeared higher frequency than BALB /c and wild mice. These results indicate that the factor related to binding X-Y chromosome is specific to strains.

• 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.

• The Korean Journal of Zoology
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• v.19 no.4
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• pp.179-186
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• 1976

DNA repari synthesis and chromosome aberrations induced by various concentrations of alkylating agents (MMS, MNNG, MMC) in cultured human lymphocytes and HeLa $S_3$ cells were studied to determine the possibility of correlation between these two types of biological phenomena, and the results obtained were as follows: DNA repair synthesis was detected in MMC, MNNG and MMS treated HeLa $S_3$ cells at the concentrations of $3 \\times 10^{-7}M, 1 \\times 10^{-6}M, 5 \\times 10^{-4}M$, respectively. These results indicate that MMC is the most potent mutagen followed by MNNG, and MMS is the least potent among these three types of alkylating agents. MMC and MNNG did not show any significant increases of DNA repair synthesis as dose increased, while MMS did. Chromosome aberrations induced by MMC in human lymphocytes was increased as dose increased, but not chromosome exchanges. MNNG did not induce any significant amount of chromosome aberrations with doses, and exchanges were not observed in MNNG treated cells. MMS, however, induced both chromosome aberrations and exchanges, and their rates were increased as dose increased. These results suggest that DNA repair synthesis induced by these alklating agents may not be directly related to the production of chromosome aberrations and exchanges.

• Animal Bioscience
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• v.36 no.2
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• pp.191-199
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• 2023

Objective: This study aimed to investigate the significant single nucleotide polymorphisms (SNPs) and genes associated with nine reproduction and morphological traits in three breed populations of Chinese goats. Methods: The genome-wide association of nine reproduction and morphological traits (litter size, nipple number, wattle, skin color, coat color, black dorsal line, beard, beard length, and hind leg hair) were analyzed in three Chinese native goat breeds (n = 336) using an Illumina Goat SNP50 Beadchip. Results: A total of 17 genome-wide or chromosome-wide significant SNPs associated with one reproduction trait (litter size) and six morphological traits (wattle, coat color, black dorsal line, beard, beard length, and hind leg hair) were identified in three Chinese native goat breeds, and the candidate genes were annotated. The significant SNPs and corresponding putative candidate genes for each trait are as follows: two SNPs located on chromosomes 6 (CSN3) and 24 (TCF4) for litter size trait; two SNPs located on chromosome 9 (KATNA1) and 1 (UBASH3A) for wattle trait; three SNPs located on chromosome 26 (SORCS3), 24 (DYM), and 20 (PDE4D) for coat color trait; two SNPs located on chromosome 18 (TCF25) and 15 (CLMP) for black dorsal line trait; four SNPs located on chromosome 8, 2 (PAX3), 5 (PIK3C2G), and 28 (PLA2G12B and OIT3) for beard trait; one SNP located on chromosome 18 (KCNG4) for beard length trait; three SNPs located on chromosome 17 (GLRB and GRIA2), 28 (PGBD5), and 4 for hind leg hair trait. In contrast, there were no SNPs identified for nipple number and skin color. Conclusion: The significant SNPs or genes identified in this study provided novel insights into the genetic mechanism underlying important reproduction and morphological traits of three local goat breeds in Southern China as well as further potential applications for breeding goats.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.3
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• pp.449-456
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• 2018

Objective: Nanog, a homeodomain protein, has been investigated in humans and mice using embryonic stem cells (ESCs). Because of the limited availability of ESCs, few studies have reported the function and role of Nanog in porcine ESCs. Therefore, in this study, we investigated the location of the porcine Nanog chromosome and its basal promoter activity, which might have potential applications in development of ESCs specific marker as well as understanding its operating systems in the porcine. Methods: To characterize the porcine Nanog promoter, the 5'-flanking region of Nanog was isolated from cells of mini-pig ears. BLAST database search showed that there are two porcine Nanog genomic loci, chromosome 1 and 5, both of which contain an exon with a start codon. Deletion mutants from the 5'-flanking region of both loci were measured using the Dual-Luciferase Reporter Assay System, and a fluorescence marker, green fluorescence protein. Results: Promoter activity was detected in the sequences of chromosome 5, but not in those of chromosome 1. We identified the sequences from -99 to +194 that possessed promoter activity and contained transcription factor binding sites from deletion fragment analysis. Among the transcription factor binding sites, a Sp1 was found to play a crucial role in basal promoter activity, and point mutation of this site abolished its activity, confirming its role in promoter activity. Furthermore, gel shift analysis and chromatin immunoprecipitation analysis confirmed that Sp1 transcription factor binds to the Sp1 binding site in the porcine Nanog promoter. Taken together, these results show that Sp1 transcription factor is an essential element for porcine Nanog basal activity the same as in human and mouse. Conclusion: We showed that the porcine Nanog gene is located on porcine chromosome 5 and its basal transcriptional activity is controlled by Sp1 transcription factor.

• Animal Bioscience
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• v.35 no.9
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• pp.1289-1302
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• 2022

The next generation sequencing has significantly contributed to clarify the genome structure of many species of zootechnical interest. However, to date, some portions of the genome, especially those linked to a heterogametic nature such as the Y chromosome, are difficult to assemble and many gaps are still present. It is well known that the fluorescence in situ hybridization (FISH) is an excellent tool for identifying genes unequivocably mapped on chromosomes. Therefore, FISH can contribute to the localization of unplaced genome sequences, as well as to correct assembly errors generated by comparative bioinformatics. To this end, it is necessary to have starting points; therefore, in this study, we reviewed the physically mapped genes on the Y chromosome of cattle, buffalo, sheep, goats, pigs, horses and alpacas. A total of 208 loci were currently mapped by FISH. 89 were located in the male-specific region of the Y chromosome (MSY) and 119 were identified in the pseudoautosomal region (PAR). The loci reported in MSY and PAR were respectively: 18 and 25 in Bos taurus, 5 and 7 in Bubalus bubalis, 5 and 24 in Ovis aries, 5 and 19 in Capra hircus, 10 and 16 in Sus scrofa, 46 and 18 in Equus caballus. While in Vicugna pacos only 10 loci are reported in the PAR region. The correct knowledge and assembly of all genome sequences, including those of genes mapped on the Y chromosome, will help to elucidate their biological processes, as well as to discover and exploit potentially epistasis effects useful for selection breeding programs.

• Clinical and Experimental Pediatrics
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• v.57 no.7
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• pp.333-336
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• 2014

Reports of constitutional ring chromosome 22, r(22) are rare. Individuals with r(22) present similar features as those with the 22q13 deletion syndrome. The instability in the ring chromosome contributes to the development of variable phenotypes. Central nervous system (CNS) atypical teratoid rhabdoid tumors (ATRTs) are rare, highly malignant tumors, primarily occurring in young children below 3 years of age. The majority of ATRT cases display genetic alterations of SMARCB1 (INI1/hSNF5 ), a tumor suppressor gene located on 22q11.2. The coexistence of a CNS ATRT in a child with a r(22) is rare. We present a case of a 4-month-old boy with 46,XY,r(22)(p13q13.3), generalized hypotonia and delayed development. High-resolution microarray analysis revealed a 3.5-Mb deletion at 22q13.31q13.33. At 11 months, the patient had an ATRT ($5.6cm{\times}5.0cm{\times}7.6cm$) in the cerebellar vermis, which was detected in the brain via magnetic resonance imaging.

• Korean Journal of Poultry Science
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• v.46 no.4
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• pp.287-296
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• 2019

Avian sex determination system involves the male ZZ and female ZW chromosomes. However, very few studies are reported the expression, functional role and importance of genes on the W chromosome because of its small and highly heterochromatic genomic regions. Recent studies demonstrated that the W chromosome may have critical roles in physiology, sex determination and subsequent sexual differentiation in chickens. Therefore, gene annotation, including describing the expression and function of genes in the chicken W chromosome, is needed. In this study, we have searched the W chromosome of chickens and selected a total of 36 genes to evaluated their specific expression in the testis and ovary at various developmental stages such as embryonic day 6 (E6), hatch and adult. Interestingly, out of 36 genes in chicken W chromosome, we have found seven female-specific expression at E6.5 day, indicating that they are functionally related to female chicken gonadal differentiation. In addition, we have identified the stage specific gene expression from the sex specific genes. Furthermore, we analyzed the relative location of genes in the chicken W chromosome. Collectively, these results will contribute molecular insights into the sexual determination, differentiation and female development based on the W chromosome.

• Journal of Mushroom
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• v.12 no.1
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• pp.63-66
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• 2014

The karyotype of F. velutipes Korean cultivar, Fv 3-6, was compared with those of Japanese cultivars, Fv 0-1, Fv 1-5, Fv 11-1, by CHEF gel electrophoresis. The Korean cultivar, Fv 3-6, showed the difference from the three Japanese cultivars in number and size of chromosomes; the Fv 3-6 had two and one more chromosomes then Fv 0-1 and Fv 11-4, and Fv 1-5 had, respectively. The karyotyping by CHEF gel electrophoresis is quite suitable to define new Korean cultivars against Japanese cultivars.

• The Korean Journal of Mycology
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• v.17 no.2
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• pp.76-81
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• 1989

The mitotic nuclear divisions in hyphae and chromosome number in 10 strains of Fusarium oxysporum were studies with the aid of Giemsa-HCl techniques. The chromosome number of fungi was ranged from 4 to 8. Of the 10 strains (F. oxysporum f. sp. lycoperici, F. oxysporum Kangnung D2) are n=4; two (F. oxysporum Sachun3, F. oxysporum S Kohung D2) n=5; five (F. oxysporum S Kohung 3, F. oxysporum CS Hongchun D16, F. oxysporum S Bosung 5, F. oxysporum SSunchun4 and F. oxysporum S Haenam 4) n=7 and one (F. oxysporum from the Australia) are n=8. These results along with my previous papers indicate that the basic chromosome number of the F. oxysporum may be n=4 and may have been evolutionary modification within this fugal group through diploidy and aneuploidy. As additional strains are studied, the chromosome number should help to reveal steps possible phylogenetic relationship within the group as well as more clearly defining taxonomic group and variation factors.