• Environmental Mutagens and Carcinogens
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• v.19 no.1
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• pp.14-19
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• 1999

Chromosome rearrangements induced in human lymphocyte after in vitro exposure to chromium were analysed by the use of fluorescence in situ hybridization(FISH) with triple combination of composite whole chromosome-specific probe for chromosome 1, 2 and 4. Chromosome aberrations was scored by the Protocol for Aberration Identification and Nomenclature Terminology (PAINT). Stable translocation was the most frequent type of aberrations and dicentrics and insertions were also observed. Chromium treatment enhanced the frequencies of stable translocations and color junctions in a dose-dependent manners, but no distinct increase of dicentrics and insertions was seen. The ratio of the yields of translocation to the yields of dicentric varied between 13 to 27. The presents results demonstrate fluorescent in situ hybridization (FISH) is useful for detecting chromosomal rearrangements induced by chromium.

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

• Environmental Mutagens and Carcinogens
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• v.17 no.1
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• pp.12-16
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• 1997

Chromosome rearrangement induced by bleomycin were identified by fluorescence in situ hybridization with probe for chromosome 4. The frequency of color junctions, translocations, dicentric and acenttic fragments increased with bleomycin dose. Different types of balanced translocation and dicentric were scored and compared. The frequency of cells exhibiting multiple aberration was higher compared to that of cells exposed to Gamma radiation suggesting that effect of bleomycin might be similar to that of high LET radiation.

• Environmental Mutagens and Carcinogens
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• v.16 no.2
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• pp.88-96
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• 1996

Fluorescence in situ hybridization (FISH) with the DNA probe for human chromosome 4 was used to analyse in vitro radiation induced chromosome rearrangement in peripheral lymphocyte. Translocations, dicentrics, acentrics and color junctions involving the painted chromosome were scored according to the Protocol for Aberration Identification and Nomenclature Terminology (PAINT) system. The frequency of chromosome rearrangements including reciprocal translocation, dicentric, acentric fragment and color junction increased with radiation dose. The frequency of dicentric chromosome reduced by the fixation time following irradiation, whereas that of translocation was relatively persistent. The applicability of FISH for scoring stable translocation for biological dosimetry was demonstrated.

• Environmental Mutagens and Carcinogens
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• v.18 no.2
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• pp.109-115
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• 1998

Fluorscence in situ hybridization with chromosome-specific probe has been shown to be a valid and rapid method for detection of chromosome rearrangements induced by chemical and physical agents. This method is useful for quantifying structural aberrations, expecially for stable ones, such as translocation and insertion, which are difficult to detect with conventional method in human lymphocyte. In order to use the FISH method as a biodosimeter for monitoring human population exposed to various chemical and physical agent, baseline level of chromosome rearragement was established. Blood from forty four healthy adults were collected and analysed with whole chromosome-specific probes by human chromosome 1,2 and 4. The frequencies of stable translocation were 2.45 per 100 cell equivalent and those of insertion, color juction, acentric and dicentric were 0.32, 3.28, 0.23 and 0.27 per 100 cell equivalent respectively. The frequencies of chromosome rearragements increased with age in both sexes except for dicenrics. From above result, stable aberrations accumulate with age and it may reflect integrated lifetime exposure of adverse environment.

• Journal of Radiation Protection and Research
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• v.24 no.1
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• pp.45-53
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• 1999

Fluorescence in situ hybridization with chromosome-specific probe has been shown to be a valid and rapid method for detection of chromosome rearrangements induced by radiation. This method is useful for quantifying structural aberrations, expecially for stable ones, such as translocation and insertion, which are difficult to detect with conventional method in human lymphocyte. In order to apply FISH method for high dose biological dosimetry, chromosomal abberations by radiation at doses of 1, 3, 5, and 7Gy were analysed with whole chromosome-specific probes by human chromosome 1, 2 and 4 according to PAINT system. The frequencies of stable translocation per cell equivalent were 0.04, 0.33, 1.22, 2.62, and 5.58 for the lymphocyte exposed to 0, 1, 3, 5, and 7Gy, respectively, and those of dicentric were 0.00, 0.06, 0.52, 1.19 and 2.44, respectively. Significantly more translocation of t(Ab), a translocated chromosome with a piece of painted acentric matrial 'b' attached to unpainted piece containing centromere 'A', than reciprocal chromosome t(Ba) was observed. The frequencies of all type of chromosome rearrangements increased with dose. From above result, FISH seemed to be useful for radiation biodosimetry by which the frequencies of various types of stable aberrations in human lymphocyte can be observed more easily than by conventional method and so will improve our ability to perform meaningful biodosimetry.

• Journal of Genetic Medicine
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• v.19 no.1
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• pp.14-21
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• 2022

Complex chromosome rearrangements (CCRs) are structural chromosomal rearrangements involving at least three chromosomes and more than two breakpoints. CCR carriers are generally phenotypically normal but related to higher risk of recurrent miscarriage and having abnormal offspring with congenital anomalies. However, most of CCR carriers are not aware of their condition until genetic analysis of either abortus or affected baby or parental karyotyping is performed. Herein, we present the case that CCR carrier patients can be identified by preimplantation genetic testing of preimplantation embryos. An infertile male patient with severe oligoasthenoteratozoospermia was diagnosed balanced reciprocal translocation, 46,XY,t(3;11) (p26;p14) at first. After attempting the first preimplantation genetic testing for structural rearrangement (PGT-SR) cycle, we found the recurrent segmental gain or loss on 21q21.3-q22.3 of five out of nine embryos. As a result of karyotype re-analysis, the patient's karyotype showed a balanced CCR involving chromosomes 3, 11, and 21 with three breakpoints 3p26, 11p14, and 21q21. The patient underwent two PGT-SR cycles, and a pregnancy was established after the transfer of an euploid embryo in the second cycle. Amniocentesis confirmed that the baby carried normal karyotype without mosaicism. At 37 weeks gestation, a healthy girl weighting 3,050 g was born.

• Biomedical Science Letters
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• v.15 no.4
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• pp.363-368
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• 2009

One of the frequent occurrences in rearrangements is chromosome inversion. Pericentric inversion is considered to be the variant of normal karyotype. We investigated the karyotypes of 1195 cases being referred to prenatal diagnosis using standard GTG banding for karyotype preparation. The chromosomal analysis revealed a total of 15 (1.26%) inversions. The characteristics of inversion type [(inv(4), inv(8), inv(9), inv(11)) were investigated on the basis of chromosomal analyses of fetuses and their parents. The results from chromosomal examination of the parents, whose fetuses were diagnosed as inversion, show that either parent might be the carrier. Inversion in human chromosome is commonly seen in normal humans and the frequency estimated to be 1 to 2% in general population and the exact amount of this phenomenon is still unclear. These results indicate that inv(8), inv(9), and inv(11) are phenotypically normal. However these may often cause clinical problems in offspring of the carrier, such as fetal wastage repeated spontaneous abortions and infertility with unknown mechanisms related to sex. We describe an inversion of human chromosome and its clinical correlation with human genetic disease.

• Genomics & Informatics
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• v.13 no.4
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• pp.102-111
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• 2015

The karyotypes of most species of crocodilians were studied using conventional and molecular cytogenetics. These provided an important contribution of chromosomal rearrangements for the evolutionary processes of Crocodylia and Sauropsida (birds and reptiles). The karyotypic features of crocodilians contain small diploid chromosome numbers (30~42), with little interspecific variation of the chromosome arm number (fundamental number) among crocodiles (56~60). This suggested that centric fusion and/or fission events occurred in the lineage, leading to crocodilian evolution and diversity. The chromosome numbers of Alligator, Caiman, Melanosuchus, Paleosuchus, Gavialis, Tomistoma, Mecistops, and Osteolaemus were stable within each genus, whereas those of Crocodylus (crocodylians) varied within the taxa. This agreed with molecular phylogeny that suggested a highly recent radiation of Crocodylus species. Karyotype analysis also suggests the direction of molecular phylogenetic placement among Crocodylus species and their migration from the Indo-Pacific to Africa and The New World. Crocodylus species originated from an ancestor in the Indo-Pacific around 9~16 million years ago (MYA) in the mid-Miocene, with a rapid radiation and dispersion into Africa 8~12 MYA. This was followed by a trans-Atlantic dispersion to the New World between 4~8 MYA in the Pliocene. The chromosomes provided a better understanding of crocodilian evolution and diversity, which will be useful for further study of the genome evolution in Crocodylia.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2003.10a
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• pp.183-192
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• 2003

With the availability of complete whole-genomes such as the human, mouse, fugu and chimpanzee chromosome 22, comparative analysis of large genomes from cross-species at varying evolutionary distances is considered one of a powerful approach for identifying coding and functional non-coding sequences. Here we describe a fast and efficient global alignment method especially for large genomic regions over mega bases pair. We used an approach for identifying all similarity regions by HSP (Highest Segment Pair) regions using local alignments and then large syntenic genome based on the both extension of anchors at HSP regions in two species and global conservation map. Using this alignment approach, we examined rearrangement loci in human chromosome 21 and chimpanzee chromosome 22. Finally, we extracted syntenic genome 30 Mb of human chromosome 21 with chimpanzee chromosome 22, and then identified genomic rearrangements (deletions and insertions ranging h size from 0.3 to 200 kb). Our experiment shows that all jnsertion/deletion (indel) events in excess of 300 bp within chimpanzee chromosome 22 and human chromosome 21 alignments in order to identify new insertions that had occurred over the last 7 million years of evolution. Finally we also discussed evolutionary features throughout comparative analyses of Ka/ks (non-synonymous / synonymous substitutions) rate in orthologous 119 genes of chromosome 21 and 53 genes of MHC-I class in human and chimpanzee genome.