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Medicine Sep 2022Chromosomal aberrations in peripheral blood are a major cause of reproductive disorders for the infertile couples. Reciprocal translocation is closely related to male...
Chromosomal aberrations in peripheral blood are a major cause of reproductive disorders for the infertile couples. Reciprocal translocation is closely related to male infertility. The breakpoint of translocation may disrupt or dysregulate important genes related to spermatogenesis. The relationship between some breakpoints of chromosome and male infertility has been paid attention. Chromosome 22q11.2 translocation has not been reported with male infertility. The purpose of this study is to evaluate the relationship between chromosome 22q11.2 translocation and male infertility. All patients were collected from the second hospital of Jilin University. Semen parameters were detected using the computer-aided semen analysis system. Cytogenetic analysis was performed using standard operating procedure. Related genes on chromosomal breakpoints were searched using online mendelian inheritance in man (OMIM). The association between this breakpoint and spermatogenesis is also discussed. We report 6 cases of translocation in chromosome 22. Of 7 breakpoints involved in these translocations, the common feature is that they all included chromosome 22q11.2 translocation and presented with oligozoospermia. The analysis of breakpoint related genes showed testis-specific serine/threonine kinase 2 (TSSK2) gene is associated with human spermatogenesis impairment. Overall, these results suggest that the breakpoint involved in translocation deserves attention from physicians in genetic counseling. The breakpoint rearrangement has the possibility of disrupting spermatogenesis. The relationship between 22q11.2 breakpoint and male infertility deserves further study.
Topics: Chromosome Aberrations; Chromosomes; Humans; Infertility, Male; Male; Oligospermia; Protein Serine-Threonine Kinases; Serine; Translocation, Genetic
PubMed: 36181097
DOI: 10.1097/MD.0000000000030790 -
Nature Cell Biology Apr 2014Chromosome translocations are catastrophic genomic events and often play key roles in tumorigenesis. Yet the biogenesis of chromosome translocations is remarkably poorly... (Review)
Review
Chromosome translocations are catastrophic genomic events and often play key roles in tumorigenesis. Yet the biogenesis of chromosome translocations is remarkably poorly understood. Recent work has delineated several distinct mechanistic steps in the formation of translocations, and it has become apparent that non-random spatial genome organization, DNA repair pathways and chromatin features, including histone marks and the dynamic motion of broken chromatin, are critical for determining translocation frequency and partner selection.
Topics: Animals; Cell Transformation, Neoplastic; Chromatin; DNA Breaks, Double-Stranded; DNA Repair; Histones; Humans; Mice; Mutation Rate; Saccharomyces cerevisiae; Translocation, Genetic
PubMed: 24691255
DOI: 10.1038/ncb2941 -
Cancer Genomics & Proteomics 2023Angioleiomyoma is a benign tumor, occurs at any age, and arises most frequently in the lower extremities. Genetic information on angioleiomyomas is restricted to six...
BACKGROUND/AIM
Angioleiomyoma is a benign tumor, occurs at any age, and arises most frequently in the lower extremities. Genetic information on angioleiomyomas is restricted to six reported abnormal karyotypes, losses in chromosome 22 and gains in Xq found by comparative genomic hybridization, and mutation analysis of notch receptor 2 (NOTCH2), NOTCH3, platelet-derived growth factor receptor beta (PDGFRB), and mediator complex subunit 12 (MED12) in a few tumors. Herein, we report the genetic findings in another three angioleiomyomas.
MATERIALS AND METHODS
The tumors were examined using G-banding and karyotyping, RNA sequencing, reverse transcription-polymerase chain reaction, Sanger sequencing, and expression analysis.
RESULTS
The first tumor carried a t(4;5)(p12;q32) translocation resulting in fusion of the cardiac mesoderm enhancer-associated non-coding RNA (CARMN in 5q32) with the TXK tyrosine kinase gene (TXK in 4p12) leading to overexpression of TXK. To our knowledge, this is the first time that a recurrent chromosome translocation and its resulting fusion gene have been described in angioleiomyomas. The second tumor carried a four-way translocation, t(X;3;4;16)(q22;p11;q11;p13) which fused the myosin heavy chain 11 gene (MYH11 in 16p13) with intergenic sequences from Xq22 that mapped a few kilobase pairs distal to the insulin receptor substrate 4 gene (IRS4), resulting in enhanced IRS4 expression. The third angioleiomyoma carried another rearrangement of chromosome band Xq22, t(X;9)(q22;q32), as the sole cytogenetic aberration, but no material was available for further molecular investigation.
CONCLUSION
Our data, together with previously reported abnormal karyotypes in angioleiomyomas, show the presence of two recurrent genetic pathways in this tumor type: The first is characterized by presence of the translocation t(4;5)(p12;q32), which generates a CARMN::TXK chimera. The second is recurrent rearrangement of Xq22 resulting in overexpression of IRS4.
Topics: Humans; Angiomyoma; Comparative Genomic Hybridization; Chromosome Aberrations; Translocation, Genetic; Transcription Factors; Abnormal Karyotype
PubMed: 37889065
DOI: 10.21873/cgp.20405 -
Medicine Jul 2023Asthenozoospermia (AZS) is the commonest cause of male-related infertility. The patients with AZS easily exhibit infertility, with their wives having spontaneous... (Observational Study)
Observational Study
Asthenozoospermia (AZS) is the commonest cause of male-related infertility. The patients with AZS easily exhibit infertility, with their wives having spontaneous miscarriages or seeking assisted reproductive treatment. Reciprocal chromosomal translocation (RCT) is an important chromosome structural abnormality and has been reported to affect sperm motility. Genetic counseling for male RCT patients with AZS is still a challenge. This study reported 4 RCT carriers, which were 46,XY,t(1;6) (p36.1;p21), 46,XY,t (6;10) (p21;q11.2), 46,XY,t (6;11) (p21;p15), and 46,XY,t (6;17) (p21;q21), respectively. The association between chromosome 6p21 translocation and AZS is discussed, considering 19 published cases as well. In 6 patients with available semen parameters and 4 patients in this study, all of them were diagnosed with AZS. The SLC26A8 gene and the DNAH8 gene located on chromosome 6p21 are closely related to AZS by gene search using OMIM. For the chromosome 6p21 breakpoint, 72 pathogenic genes were found through the DECIPHER search. Gene ontology analysis showed that these target genes have several molecular functions and are strongly involved in various biological processes. The proteins expressed by these genes are involved in multiple cellular components. These results suggest that the breakpoint of chromosome 6p21 in male RCT carriers is closely related to AZS. The breakpoint may disrupt the structure and function of related genes, resulting in reduced sperm motility. Karyotype analysis should be recommended for AZS patients. Chromosomes and breakpoints involved in RCT should be paid attention to in genetic counseling for patients.
Topics: Male; Humans; Asthenozoospermia; Translocation, Genetic; Infertility, Male; Chromosome Aberrations; Karyotype
PubMed: 37417617
DOI: 10.1097/MD.0000000000034318 -
Genes Jul 2022Data for the chromosomal FISH mapping localization of (AGT) are compiled for 37 species belonging 27 families; for 24 species and 14 families, this is the first such...
Data for the chromosomal FISH mapping localization of (AGT) are compiled for 37 species belonging 27 families; for 24 species and 14 families, this is the first such report. The chromosome number and length ranged from 14-136 and 0.56-14.48 μm, respectively. A total of 23 woody plants presented chromosome length less than 3 μm, thus belonging to the small chromosome group. Telomeric signals were observed at each chromosome terminus in 38 plants (90.5%) and were absent at several chromosome termini in only four woody plants (9.5%). Non-telomeric signals were observed in the chromosomes of 23 plants (54.8%); in particular, abundant non-telomeric (AGT) was obviously observed in . Telomeric signals outside of the chromosome were observed in 11 woody plants (26.2%). Overall, ten (AGT) signal pattern types were determined, indicating the complex genome architecture of the 37 considered species. The variation in signal pattern was likely due to chromosome deletion, duplication, inversion, and translocation. In addition, large primary constriction was observed in some species, probably due to or leading to chromosome breakage and the formation of new chromosomes. The presented results will guide further research focused on determining the chromosome number and disclosing chromosome rearrangements of woody plants.
Topics: Chromosome Mapping; Gene Rearrangement; Humans; In Situ Hybridization, Fluorescence; Telomere; Translocation, Genetic
PubMed: 35886022
DOI: 10.3390/genes13071239 -
BMC Genomics Jan 2018We previously reported the development of a set of Gossypium hirsutum-G. australe alien chromosome addition lines. Naturally, however, G. hirsutum-G. australe chromosome...
BACKGROUND
We previously reported the development of a set of Gossypium hirsutum-G. australe alien chromosome addition lines. Naturally, however, G. hirsutum-G. australe chromosome exchanges were very limited, impeding the stable transference of useful genes from G. australe (GG genome) into the most cultivated cotton, G. hirsutum (AADD).
RESULTS
In the present report, the pollen from a pentaploid (2n = AADDG) of G. hirsutum-G. australe was irradiated with seven different doses ranging from 10 to 40 Grays and used to pollinate emasculated flowers of G. hirsutum over three consecutive years. Irradiation greatly increased the genetic recombination rates of the G. hirsutum and G. australe chromosomes and a total of 107 chromosome introgression individuals in 192 GISH-negative (with no GISH signal on chromosome) survived individuals, 11 chromosome translocation individuals (containing 12 chromosome translocation events) and 67 chromosome addition individuals were obtained in 70 GISH-positive (with GISH signal(s) on chromosome(s)) survived individuals, which are invaluable for mining desirable genes from G. australe. Multicolor genomic in situ hybridization results showed that there were three types of translocation, whole arm translocation, large alien segment translocation and small alien segment translocation, and that all translocations occurred between the G-genome and the A-subgenome chromosomes in G. hirsutum. We also found that higher doses induced much higher rates of chromosome variation but also greatly lowered the seed viability and seedling survivability.
CONCLUSIONS
Irradiation has been successfully employed to induce chromosome introgressions and chromosome translocations and promote chromosome exchanges between cultivated and wild species. In addition, by balancing the rates of chromosome introgression and translocation to those of seed set, seed germination, and seedling rates in the M1 generation, we conclude that the dosage of 20 Grays is the most suitable. The established methodology may guide the utilization of the tertiary gene pool of Gossypium species such as G. australe in cotton breeding in the future.
Topics: Chromosome Aberrations; Chromosomes, Plant; Germination; Gossypium; Translocation, Genetic
PubMed: 29301494
DOI: 10.1186/s12864-017-4398-7 -
Oncogene Jun 2021Translocations arise when an end of one chromosome break is mistakenly joined to an end from a different chromosome break. Since translocations can lead to developmental... (Review)
Review
Translocations arise when an end of one chromosome break is mistakenly joined to an end from a different chromosome break. Since translocations can lead to developmental disease and cancer, it is important to understand the mechanisms leading to these chromosome rearrangements. We review how characteristics of the sources and the cellular responses to chromosome breaks contribute to the accumulation of multiple chromosome breaks at the same moment in time. We also discuss the important role for chromosome break location; how translocation potential is impacted by the location of chromosome breaks both within chromatin and within the nucleus, as well as the effect of altered mobility of chromosome breaks. A common theme in work addressing both temporal and spatial contributions to translocation is that there is no shortage of examples of factors that promote translocation in one context, but have no impact or the opposite impact in another. Accordingly, a clear message for future work on translocation mechanism is that unlike normal DNA metabolic pathways, it isn't easily modeled as a simple, linear pathway that is uniformly followed regardless of differing cellular contexts.
Topics: Animals; Chromatin; Chromosomes; DNA Breaks, Double-Stranded; DNA Repair; Humans; Neoplasms; Translocation, Genetic
PubMed: 34103687
DOI: 10.1038/s41388-021-01856-9 -
The Plant Journal : For Cell and... Oct 2022Aegilops species represent the most important gene pool for breeding bread wheat (Triticum aestivum). Thus, understanding the genome evolution, including chromosomal...
Aegilops species represent the most important gene pool for breeding bread wheat (Triticum aestivum). Thus, understanding the genome evolution, including chromosomal structural rearrangements and syntenic relationships among Aegilops species or between Aegilops and wheat, is important for both basic genome research and practical breeding applications. In the present study, we attempted to develop subgenome D-specific fluorescence in situ hybridization (FISH) probes by selecting D-specific oligonucleotides based on the reference genome of Chinese Spring. The oligo-based chromosome painting probes consisted of approximately 26 000 oligos per chromosome and their specificity was confirmed in both diploid and polyploid species containing the D subgenome. Two previously reported translocations involving two D chromosomes have been confirmed in wheat varieties and their derived lines. We demonstrate that the oligo painting probes can be used not only to identify the translocations involving D subgenome chromosomes, but also to determine the precise positions of chromosomal breakpoints. Chromosome painting of 56 accessions of Ae. tauschii from different origins led us to identify two novel translocations: a reciprocal 3D-7D translocation in two accessions and a complex 4D-5D-7D translocation in one accession. Painting probes were also used to analyze chromosomes from more diverse Aegilops species. These probes produced FISH signals in four different genomes. Chromosome rearrangements were identified in Aegilops umbellulata, Aegilops markgrafii, and Aegilops uniaristata, thus providing syntenic information that will be valuable for the application of these wild species in wheat breeding.
Topics: Aegilops; Chromosome Painting; Chromosomes, Plant; In Situ Hybridization, Fluorescence; Oligonucleotides; Plant Breeding; Translocation, Genetic; Triticum
PubMed: 35998122
DOI: 10.1111/tpj.15926 -
Radiation Oncology (London, England) Aug 2022As one of the most common chromosomal causes, chromosome translocation leads to T-cell acute lymphoblastic leukemia (T-ALL). Ku70 is one of the key factors of...
BACKGROUND
As one of the most common chromosomal causes, chromosome translocation leads to T-cell acute lymphoblastic leukemia (T-ALL). Ku70 is one of the key factors of error-prone DNA repair and it may end in translocation. So far, the direct correlation between Ku70 and translocation has not been assessed. This study aimed to investigate the association between Ku70 and translocation in human lymphocytes after radiation and T-ALL.
METHODS
Peripheral blood lymphocytes (PBLs) from volunteers and human lymphocyte cell line AHH-1 were irradiated with X-rays to form the chromosome translocations. Phytohemagglutinin (PHA) was used to stimulate lymphocytes. The frequency of translocation was detected by fluorescence in situ hybridization (FISH). Meanwhile, the expression of Ku70 was detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot. Furthermore, Ku70 interference, overexpression and chemical inhibition were used in AHH-1 cell lines to confirm the correlation. Finally, the expression of Ku70 in T-ALL samples with or without translocation was detected.
RESULTS
The expression of Ku70 and frequencies of translocation were both significantly increased in PBLs after being irradiated by X-rays, and a positive correlation between the expression (both mRNA and protein level) of Ku70 and the frequency of translocation was detected (r = 0.4877, P = 0.004; r = 0.3038, P = 0.0358 respectively). Moreover, Ku70 interference decreased the frequency of translocations, while the frequency of translocations was not significantly affected after Ku70 overexpression. The expression of Ku70 and frequencies of translocation were both significantly increased in cells after irradiation, combined with chemical inhibition (P < 0.01). The protein level and mRNA level of Ku70 in T-ALL with translocation were obviously higher than T-ALL with normal karyotype (P = 0.009, P = 0.049 respectively).
CONCLUSIONS
Ku70 is closely associated with the frequency of chromosome translocation in human lymphocytes after radiation and T-ALL. Ku70 might be a radiation damage biomarker and a potential tumor therapy target.
Topics: Humans; In Situ Hybridization, Fluorescence; Lymphocytes; Precursor T-Cell Lymphoblastic Leukemia-Lymphoma; RNA, Messenger; T-Lymphocytes; Translocation, Genetic
PubMed: 35986335
DOI: 10.1186/s13014-022-02113-3 -
Annals of the New York Academy of... Mar 2014Type II topoisomerases are essential enzymes that modulate DNA under- and overwinding, knotting, and tangling. Beyond their critical physiological functions, these... (Review)
Review
Type II topoisomerases are essential enzymes that modulate DNA under- and overwinding, knotting, and tangling. Beyond their critical physiological functions, these enzymes are the targets for some of the most widely prescribed anticancer drugs (topoisomerase II poisons) in clinical use. Topoisomerase II poisons kill cells by increasing levels of covalent enzyme-cleaved DNA complexes that are normal reaction intermediates. Drugs such as etoposide, doxorubicin, and mitoxantrone are frontline therapies for a variety of solid tumors and hematological malignancies. Unfortunately, their use also is associated with the development of specific leukemias. Regimens that include etoposide or doxorubicin are linked to the occurrence of acute myeloid leukemias that feature rearrangements at chromosomal band 11q23. Similar rearrangements are seen in infant leukemias and are associated with gestational diets that are high in naturally occurring topoisomerase II-active compounds. Finally, regimens that include mitoxantrone and epirubicin are linked to acute promyelocytic leukemias that feature t(15;17) rearrangements. The first part of this article will focus on type II topoisomerases and describe the mechanism of enzyme and drug action. The second part will discuss how topoisomerase II poisons trigger chromosomal breaks that lead to leukemia and potential approaches for dissociating the actions of drugs from their leukemogenic potential.
Topics: Animals; Antineoplastic Agents; Catechin; Cell Transformation, Neoplastic; Chromosome Breakage; Curcumin; DNA Topoisomerases, Type II; Genistein; Humans; Infant; Leukemia; Neoplasms, Second Primary; Translocation, Genetic
PubMed: 24495080
DOI: 10.1111/nyas.12358