Cytogenetic and Genome Research最新文献

{"title":"Loss of One X and the Y Chromosome Changes the Configuration of the X Inactivation Center in the Genus Tokudaia.","authors":"Luisa Matiz-Ceron, Miki Okuno, Takehiko Itoh, Ikuya Yoshida, Shusei Mizushima, Atsushi Toyoda, Takamichi Jogahara, Asato Kuroiwa","doi":"10.1159/000539294","DOIUrl":"10.1159/000539294","url":null,"abstract":"<p><strong>Introduction: </strong>X chromosome inactivation (XCI) is an essential mechanism for dosage compensation between females and males in mammals. In females, XCI is controlled by a complex, conserved locus termed the X inactivation center (Xic), in which the lncRNA Xist is the key regulator. However, little is known about the Xic in species with unusual sex chromosomes. The genus Tokudaia includes three rodent species endemic to Japan. Tokudaia osimensis and Tokudaia tokunoshimensis lost the Y chromosome (XO/XO), while Tokudaia muenninki (TMU) acquired a neo-X region by fusion of the X chromosome and an autosome (XX/XY). We compared the gene location and structure in the Xic among Tokudaia species.</p><p><strong>Methods: </strong>Gene structure of nine genes in Xic was predicted, and the gene location and genome sequences of Xic were compared between mouse and Tokudaia species. The expression level of the gene was confirmed by transcripts per million calculation using RNA-seq data.</p><p><strong>Results: </strong>Compared to mouse, the Xic gene order and location were conserved in Tokudaia species. However, remarkable structure changes were observed in lncRNA genes, Xist and Tsix, in the XO/XO species. In Xist, important functional repeats, B-, C-, D-, and E-repeats, were partially or completely lost due to deletions in these species. RNA-seq data showed that female-specific expression patterns of Xist and Tsix were confirmed in TMU, however, not in the XO/XO species. Additionally, three deletions and one inversion were confirmed in the intergenic region between Jpx and Ftx in the XO/XO species.</p><p><strong>Conclusion: </strong>Our findings indicate that even if the Xist and Tsix lncRNAs are expressed, they are incapable of producing a successful and lasting XCI in the XO/XO species. We hypothesized that the significant structure change in the intergenic region of Jpx-Ftx resulted in the inability to perform the XCI, and, as a result, a lack of Xist expression. Our results collectively suggest that structural changes in the Xic occurred in the ancestral lineage of XO/XO species, likely due to the loss of one X chromosome and the Y chromosome as a consequence of the degradation of the XCI system.</p>","PeriodicalId":11206,"journal":{"name":"Cytogenetic and Genome Research","volume":" ","pages":"23-32"},"PeriodicalIF":1.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140956719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Isodicentric Y Chromosome with Multiple Breakpoints in the Pseudoautosomal Region 1.","authors":"Yasuko Ogiwara, Yoshitomo Kobori, Erina Suzuki, Atsushi Hattori, Kanako Tanase-Nakao, Akiyoshi Osaka, Toshiyuki Iwahata, Hiroshi Okada, Yoko Kuroki, Maki Fukami","doi":"10.1159/000540634","DOIUrl":"10.1159/000540634","url":null,"abstract":"<p><strong>Introduction: </strong>Isodicentric Y chromosomes are relatively common structural variants of the human genome. The underlying mechanism of isodicentric Y chromosomes with short arm breakpoints [idic(Yq)] remains to be clarified.</p><p><strong>Case presentation: </strong>We encountered a Japanese man with azoospermia and mild short stature. G-banding and array-based comparative genomic hybridization indicated that his karyotype was 45,X/46,X,idic(Y)(qter→p11.32::p11.32→qter) with a ∼1.8 Mb terminal deletion. Whole-genome sequencing suggested that the Y chromosome had four breakpoints in a ∼7 kb region of the pseudoautosomal region 1 (PAR1).</p><p><strong>Conclusion: </strong>This case was assumed to have an idic(Yq) resulting from multiple DNA double-strand breaks in PAR1. This rearrangement may have been facilitated by the PAR1-specific chromatin architecture. The clinical features of the patient can be ascribed to SHOX haploinsufficiency and the presence of a 45,X cell line, although copy-number gains of some Yq genes and the size reduction of PAR1 may also contribute to his spermatogenic failure.</p>","PeriodicalId":11206,"journal":{"name":"Cytogenetic and Genome Research","volume":" ","pages":"133-138"},"PeriodicalIF":1.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141792196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ISCN 2024 - An International System for Human Cytogenomic Nomenclature (2024).","authors":"","doi":"10.1159/000538512","DOIUrl":"https://doi.org/10.1159/000538512","url":null,"abstract":"","PeriodicalId":11206,"journal":{"name":"Cytogenetic and Genome Research","volume":"164 Suppl 1","pages":"1-224"},"PeriodicalIF":1.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142686404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dosage Effect of the Ph1 Locus on Homologous Crossovers in a Segment of Chromosome 1B of Bread Wheat (Triticum aestivum L.).","authors":"Adam J Lukaszewski","doi":"10.1159/000541484","DOIUrl":"10.1159/000541484","url":null,"abstract":"<p><strong>Introduction: </strong>The Ph1 locus in polyploid wheat enforces strictly bivalent behaviour in meiotic metaphase I, by preventing homoeologues from crossing over. It has always been considered as completely dominant as no homoeologous metaphase I pairing has ever been detected with its single dose present. However, Ph1 also affects pairing and crossing over of homologous chromosomes.</p><p><strong>Methods: </strong>Homologous crossover frequencies with Ph1 in two, one, and null doses were scored cytologically, as exchanges within a ca. 9.5-9.9 Mbp terminal wheat segment of a wheat-rye translocation T-9 and corresponding segments in chromosome arms 1BS originating from four wheat cultivars.</p><p><strong>Results: </strong>In all cases, the crossover rates in the tested homologous segment of wheat genome, with a single dose of Ph1 present, were intermediate between those at two and null Ph1 doses. Averaging across all four chromosomes, the crossover rate with a single dose of Ph1 present was 37% higher from that with two doses and 46.4% lower of that with a zero dosage.</p><p><strong>Conclusion: </strong>The Ph1 locus in wheat affects homologues and appears to operate in a dosage-dependent manner.</p>","PeriodicalId":11206,"journal":{"name":"Cytogenetic and Genome Research","volume":" ","pages":"165-169"},"PeriodicalIF":1.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142281875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Front & Back Matter","authors":"","doi":"10.1159/000533215","DOIUrl":"https://doi.org/10.1159/000533215","url":null,"abstract":"","PeriodicalId":11206,"journal":{"name":"Cytogenetic and Genome Research","volume":"162 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45240466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Front & Back Matter","authors":"","doi":"10.1159/000530487","DOIUrl":"https://doi.org/10.1159/000530487","url":null,"abstract":"","PeriodicalId":11206,"journal":{"name":"Cytogenetic and Genome Research","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49441823","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Front & Back Matter","authors":"","doi":"10.1159/000529882","DOIUrl":"https://doi.org/10.1159/000529882","url":null,"abstract":"","PeriodicalId":11206,"journal":{"name":"Cytogenetic and Genome Research","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48697157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diversity and Evolution of Highly Repetitive DNA Sequences Constituting Chromosome Site-Specific Heterochromatin in Two Gerbillinae Species.","authors":"Yoshinobu Uno, Kazumi Matsubara, Jun Inoue, Johji Inazawa, Akio Shinohara, Chihiro Koshimoto, Kenji Ichiyanagi, Yoichi Matsuda","doi":"10.1159/000533716","DOIUrl":"10.1159/000533716","url":null,"abstract":"<p><p>Constitutive heterochromatin, consisting of repetitive sequences, diverges very rapidly; therefore, its nucleotide sequences and chromosomal distributions are often largely different, even between closely related species. The chromosome C-banding patterns of two Gerbillinae species, Meriones unguiculatus and Gerbillus perpallidus, vary greatly, even though they belong to the same subfamily. To understand the evolution of C-positive heterochromatin in these species, we isolated highly repetitive sequences, determined their nucleotide sequences, and characterized them using chromosomal and filter hybridization. We obtained a centromeric repeat (MUN-HaeIII) and a chromosome 13-specific repeat (MUN-EcoRI) from M. unguiculatus. We also isolated a centromeric/pericentromeric repeat (GPE-MBD) and an interspersed-type repeat that was predominantly amplified in the X and Y chromosomes (GPE-EcoRI) from G. perpallidus. GPE-MBD was found to contain a 17-bp motif that is essential for binding to the centromere-associated protein CENP-B. This indicates that it may play a role in the formation of a specified structure and/or function of centromeres. The nucleotide sequences of the three sequence families, except GPE-EcoRI, were conserved only in Gerbillinae. GPE-EcoRI was derived from the long interspersed nuclear elements 1 retrotransposon and showed sequence homology throughout Muridae and Cricetidae species, indicating that the repeat sequence occurred at least in the common ancestor of Muridae and Cricetidae. Due to a lack of assembly data of highly repetitive sequences constituting heterochromatin in whole-genome sequences of vertebrate species published to date, the knowledge obtained in this study provides useful information for a deep understanding of the evolution of repetitive sequences in not only rodents but also in mammals.</p>","PeriodicalId":11206,"journal":{"name":"Cytogenetic and Genome Research","volume":" ","pages":"42-51"},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10242173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Applicability of Scoring Calyculin A-Induced Premature Chromosome Condensation Objects for Dose Assessment Including for Radiotherapy Patients.","authors":"Mingzhu Sun, Jayne Moquet, David Lloyd, Stephen Barnard, Selvakumar Anbalagan, Harriet Steel, Aurore Sommer, Lone Gothard, Navita Somaiah, Elizabeth Ainsbury","doi":"10.1159/000534656","DOIUrl":"10.1159/000534656","url":null,"abstract":"<p><p>As an extension to a previous study, a linear calibration curve covering doses from 0 to 10 Gy was constructed and evaluated in the present study using calyculin A-induced premature chromosome condensation (PCC) by scoring excess PCC objects. The main aim of this study was to assess the applicability of this PCC assay for doses below 2 Gy that are critical for triage categorization. Two separate blind tests involving a total of 6 doses were carried out; 4 out of 6 dose estimates were within the 95% confidence limits (95% CL) with the other 2 just outside. In addition, blood samples from five cancer patients undergoing external beam radiotherapy (RT) were also analyzed, and the results showed whole-body dose estimates statistically comparable to the dicentric chromosome assay (DCA) results. This is the first time that calyculin A-induced PCC was used to analyze clinical samples by scoring excess objects. Although dose estimates for the pre-RT patient samples were found to be significantly higher than the mean value for the healthy donors and were also significantly higher than those obtained using DCA, all these pre-treatment patients fell into the same category as those who may have received a low dose (&lt;1 Gy) and do not require immediate medical care during emergency triage. Additionally, for radiological accidents with unknown exposure scenario, PCC objects and rings can be scored in parallel for the assessment of both low- and high-dose exposures. In conclusion, scoring excess objects using calyculin A-induced PCC is confirmed to be another potential biodosimetry tool in radiological emergency particularly in mass casualty scenarios, even though the data need to be interpreted with caution when cancer patients are among the casualties.</p>","PeriodicalId":11206,"journal":{"name":"Cytogenetic and Genome Research","volume":" ","pages":"143-153"},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10946622/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50161100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative Cytogenetic Analysis of Diploid and Triploid Pacific Abalone, Haliotis discus hannai.","authors":"Jianpeng Zhang, Yi Wang, Ying Lu, Weiwei You, Xuan Luo, Caihuan Ke","doi":"10.1159/000535045","DOIUrl":"10.1159/000535045","url":null,"abstract":"<p><strong>Introduction: </strong>The Pacific abalone, Haliotis discus hannai, is one of the most commercially important marine shellfish in China. Cell engineering breeding is an important tool in abalone genetic breeding, and the triploids obtained through this method have high commercial value. However, current research mainly focuses on establishing induction methods and evaluating the growth traits of triploids, while there is a lack of basic research on triploid cytogenetics.</p><p><strong>Method: </strong>In this study, Cytogenetic analysis of triploid Haliotis discus hannai larvae (produced by chemical treatment) and diploid larvae was performed.</p><p><strong>Result: </strong>The results showed that triploid H. discus hannai had a chromosome number of 3n = 54, consisting of 30 metacentric (m) and 24 submetacentric (sm) chromosomes, while the diploids had a chromosome number of 2n = 36, consisting of 20 metacentric (m) and 16 submetacentric (sm) chromosomes. Notably, both triploids and diploids displayed variation in the number of NORs and/or their diameter. The average number of NORs in triploid was significantly higher than that in diploids (p &lt; 0.05), but the average diameter of NORs of triploid was no significant different from that of diploid (p &gt; 0.05). Additionally, 5S rDNA localization to 3 submetacentric chromosomes was observed in triploids, compared to 2 submetacentric chromosomes in diploids. The number of 18S rDNA sites displayed positional conservancy and quantitative variability in both diploids and triploids. Specifically, 18S rDNA was found at the end of the chromosome in both groups, with triploids exhibiting a significantly higher number of loci than diploids (p &lt; 0.01).</p><p><strong>Conclusion: </strong>This study provides valuable insights into the cytogenetic characteristics of triploid H. discus hannai, which could facilitate further research on the stability of the chromosome set in this species.</p>","PeriodicalId":11206,"journal":{"name":"Cytogenetic and Genome Research","volume":" ","pages":"327-333"},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"92153154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}