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Correlation between Reasons for Prescription and Karyotype Results in Patients Referred for Suspected Chromosomal Abnormalities
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作者 Zhou Patricia Deh Malika Joane Astrid Dieth +6 位作者 Quidana Désirée Coulibaly Mimbra Olivia Annick Bouatinin Bi You Etienne Bazago Goulai Abou Joël Landry Okon Brahima Doukouré Mohenou Isidore Jean-Marie Diomandé Gnangoran Victor Yao 《Open Journal of Genetics》 2023年第2期97-103,共7页
Karyotype prescription is based on clinical signs (or reasons for karyotype prescription) which are phenotypic manifestations associated with chromosomal abnormalities. The aim of this study was to establish a corresp... Karyotype prescription is based on clinical signs (or reasons for karyotype prescription) which are phenotypic manifestations associated with chromosomal abnormalities. The aim of this study was to establish a correspondence between karyotype indications and their results in patients. This was a retrospective study that was carried out in the Histology-Embryology-Cytogenetics laboratory of the University Hospital of Cocody-Abidjan from 2014 to 2019. 58 patient files were identified and included the indication or reason for prescribing a constitutional karyotype and the biological result obtained. An individual data sheet was used to collect the data. 17 reasons for prescription were identified and divided into 2 groups. Sexual ambiguity was the most frequent reason (29.3%). The first group (G1) represented the 10 reasons for which the karyotype results were normal. The second group (G2) corresponded of the 7 motives with normal or abnormal karyotype results. Several anomalies were listed according to these reasons: inversions, mosaics (anomalies of number and structure) and trisomy 21. The last was the most frequent chromosomal anomaly (69.24%). It was found in several reasons for karyotype prescription: malformations, neurological disorders, suspected trisomy and cardiac pathology. Several factors could explain these results, among which are the limits of the karyotype and the non-genetic causes that can induce these abnormal phenotypes. Complementary examinations to the karyotype are molecular cytogenetic techniques, notably fluorescence in situ hybridization (FISH) and array comparative genomic hybridization (Array-CGH). 展开更多
关键词 DIAGNOSIS Reasons for Prescription karyotype Chromosomal Abnormalities
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Studies on the Karyotype of Two Species in Orius Wolff (Hemiptera: Heteroptera: Anthocoridae) 被引量:4
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作者 王义平 卜文俊 张虎芳 《Entomotaxonomia》 CSCD 北大核心 2002年第2期103-106,共4页
The karyotype of two Chinese species in Orius were studied in male germ cells prepared on air dried slides stained with Giemsa. It is reported that two species have 24 chromosomes in diploid and X Y sex chromoso... The karyotype of two Chinese species in Orius were studied in male germ cells prepared on air dried slides stained with Giemsa. It is reported that two species have 24 chromosomes in diploid and X Y sex chromosomal mechanism. But the beha vior of chromosomes during meiosis between two species is different. Which show in the arrangment and location of the X chromosome and autosome at the late diakinesis as well as metaphase stage respectively and so on. These characteristics may be used in ta xonomy among species of Orius . 展开更多
关键词 HEMIPTERA ANTHOCORIDAE ORIUS karyotype CHROMOSOME
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Karyotype Study on Scilla scilloides (Lindl.) Druce in Yantai 被引量:1
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作者 王爱云 赵彦宏 +1 位作者 刘林德 王丽娟 《Agricultural Science & Technology》 CAS 2008年第5期99-101,共3页
[Objective] The aim of this study was to investigate the chromosome number and the karyotype of Scilla scilloides in Yantai.[Method]Root tips of Scilla scilloides were pretreated by 8-hydroxyquinoline,then fixed,disso... [Objective] The aim of this study was to investigate the chromosome number and the karyotype of Scilla scilloides in Yantai.[Method]Root tips of Scilla scilloides were pretreated by 8-hydroxyquinoline,then fixed,dissociated and stained for slice production.The chromosome number was analyzed by microscopic examination,and then cells with good chromosomal morphology and dispersal chromosome were studied by microscopic photos.[Result]The somatic chromosome number of Scilla scilloides in Yantai was 2n=16+1Bs,while the karyotype formula was K(2n)=2x=16+1Bs=6m+4sm(2SAT)+4st+2t+1Bs and the karyotype classification was "3B" type.[Conclusion]Karyotype comparison,division of cell type and evolution of Scilla scilloides in Yantai are discussed,which provides basis for cytogenetics,evolutionary genetics,modern taxonomy and genetic breeding. 展开更多
关键词 Scilla scilloides karyotype ANALYSIS CHROMOSOME
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Studies on the Karyotype of Three Species in the Genus Orius Wolff (Hemiptera:Anthocoridae) 被引量:2
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作者 王义平 卜文俊 +1 位作者 张虎芳 吴鸿 《Entomotaxonomia》 CSCD 北大核心 2007年第3期205-208,共4页
Karyotype of 3 species of the genus Orius Wolff were firstly studied using the Giemsa staining and squashing slides method in male germ cell. It is reported that number of chromosome and system of sex chromosome of ha... Karyotype of 3 species of the genus Orius Wolff were firstly studied using the Giemsa staining and squashing slides method in male germ cell. It is reported that number of chromosome and system of sex chromosome of haploid chromosome complement of these species is n=11A+X (Y) in the first meiotic stage. However, the behavior of chromosomes among the species are different distinctly, thus cytotaxonomic character can be adopted to the identification among the three species. 展开更多
关键词 HEMIPTERA ANTHOCORIDAE ORIUS CHROMOSOME karyotype
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Karyotype Analysis of Lycium ruthenicum Murr. 被引量:3
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作者 杨雪君 徐雯 +3 位作者 裴毅 毛金枫 聂江力 张伟 《Agricultural Science & Technology》 CAS 2016年第10期2271-2273,2276,共4页
Karyotype analysis of Lycium ruthenicum Murr. was carried out in this study. The results showed that the chromosome number was 2n=2x=24; the arm index was 48; the ratio of the longest chromosome to the shortest one wa... Karyotype analysis of Lycium ruthenicum Murr. was carried out in this study. The results showed that the chromosome number was 2n=2x=24; the arm index was 48; the ratio of the longest chromosome to the shortest one was 1.31; the proportions of chromosomes with arm ratio higher than 2 was 0.08; the asymmetry index was 57.02; the karyotype type was 2A; and the karyotype formula was 2n=-24=20m+4sm. 展开更多
关键词 Lycium ruthenicum Murr. CHROMOSOME karyotype analysis
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Morphological Difference and Karyotype of Pelteobagrus fulvidraco in Dongting Lake Water System 被引量:4
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作者 刘良国 邹万生 +2 位作者 杨春英 罗玉双 杨品红 《Agricultural Science & Technology》 CAS 2011年第10期1521-1524,共4页
[Objective] The research aimed to study the morphological characteristics and karyotype of Pelteobagrus fulvidraco in Dongting Lake water system.[Method] By using the conventional biological morphometry,PHA and colchi... [Objective] The research aimed to study the morphological characteristics and karyotype of Pelteobagrus fulvidraco in Dongting Lake water system.[Method] By using the conventional biological morphometry,PHA and colchicine injection method in vivo,the morphological characteristics and karyotype of P.fulvidraco in Yuanshui River and Lishui River of Dongting Lake were analyzed.[Result] In three ratio traits including standard length/head length,standard length/caudal peduncle depth,head length/snout length,P.fulvidraco of Yuanshui River and Lishui River had significant differences(P0.05).However,the number and karyotype of their chromosomes were same.The chromosome number was 2n = 52,and the karyotype formula was 20M+12SM+10ST+10T.The number of chromosome arm was 84.[Conclusion] The research result had certain theoretical guidance significance for the protection and utilization of wild P.resource in Dongting Lake water system. 展开更多
关键词 Dongting Lake water system Yuanshui River and Lishui River P.fulvidraco Morphological characteristic karyotype
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The Karyotype of Chi-lin Fish(Varicorhinus macrolepis) from Taishan Mountain 被引量:3
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作者 庞秋香 赵博生 +2 位作者 姚东方 李亚楠 孙欢欢 《Agricultural Science & Technology》 CAS 2012年第3期649-651,共3页
[Objective] The paper was to study the karyotype of Chi-lin fish (Varicorhi- nus macrolepis) from Taishan mountain. [Method] The chromosome number and karyotype of an endemic Chi-lin fish were studied using the head... [Objective] The paper was to study the karyotype of Chi-lin fish (Varicorhi- nus macrolepis) from Taishan mountain. [Method] The chromosome number and karyotype of an endemic Chi-lin fish were studied using the head kidney cells. [Re- sult] The diploid chromosome number (2n) of Chi-lin fish was 50, and the karyotype of V. macrolepis was 2n=50,16m+14sm+20t, NF =80. No sex-chromosome was found in Chi-lin fish. [Conclusion] A detailed karyotype of this endemic cyprinid fish of Taishan Mountain was established for the first time in this study. 展开更多
关键词 CHROMOSOME karyotype Chi-lin fish (Varicorhinus macrolepis)
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Chromosomal Karyotypes of Fragaria Plants 被引量:2
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作者 时翠平 牛树启 葛会波 《Agricultural Science & Technology》 CAS 2011年第1期8-10,共3页
[Objective]This study was to analyze the karyotypes of wild diploid strawberry species,so as to provide basis for revealing the ori- gins,evolvement and genetic breeding of strawberry. [Method] Four diploid strawberry... [Objective]This study was to analyze the karyotypes of wild diploid strawberry species,so as to provide basis for revealing the ori- gins,evolvement and genetic breeding of strawberry. [Method] Four diploid strawberry species including Fragaria gracilis A. Los,Fragaria nilgerrensis Schidl,Fragaria pentaphylla A. Los. and Fragaria vesca L. were used as experimental materials to analyze their chromosomal kary- otypes. [Result]The karyotype formula for strawberry species tested was as follows: 2n =2x =14 =10m +2sm +2m* for F. gracilis A. Los, belonging to type 1B; 2n =2x =14 =14m for F. nilgerrensis Schidl,belonging to type 1A; 2n =2x =14 =12m +2sm for F. pentaphylla A. Loz. , belonging to type 1A; 2n =2x =14 =14m for F. vesca L. ,belonging to type 1A. Karyotype analysis showed that karyotypic asymmetry degree of the four species was F. gracilis A. Los. F. pentaphylla A. Loz. F. vesca L. F. nilgerrensis Schidl. [Conclusion] The evolution order of these four species was probably F. gracilis A. Los. ,F. pentaphylla A. Loz. ,F. vesca L. ,F. nilgerrensis Schidl. 展开更多
关键词 STRAWBERRY karyotype analysis DIPLOID
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Research on the Karyotype and Evolution of Drosophila melanogaster Species Group 被引量:1
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作者 邓秋红 曾庆韬 +2 位作者 钱远槐 李春选 杨勇 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第3期196-213,共18页
Mitotic metaphase chromosomes of 34 species of Drosophila melanogaster species group were examined. Certain new karyotypes were described for the first time, and their evolutionary and interspecific genetic relationsh... Mitotic metaphase chromosomes of 34 species of Drosophila melanogaster species group were examined. Certain new karyotypes were described for the first time, and their evolutionary and interspecific genetic relationships among 8 subgroups of D. melanogaster species group were analyzed systematically. The results were as follows. The basic karyotype of elegans subgroup was type A. The karyotypes of eugracilis subgroup, melanogaster subgroup, and ficusphila subgroup were all type C. The karyotypes of takahashii subgroup and suzukii subgroup were both type C and type D. The montium subgroup had six kinds of karyotypes types B, C, C', D, D', and E. The ananassae subgroup had three kinds of karyotypes: types F, G, and H. Thus, the melanogaster species group was classified into five pedigrees based on the diversity of these karyotypes: 1) elegans; 2) eugracilis-melanogasterficusphila; 3) takkahashii-suzukii; 4) montium; 5) ananassae. The above-mentioned results in karyotypic evolution were consistent with those of DNA sequence analysis reported by Yang except for the elegans subgroup and this subgroup was considered as the ancestral subgroup. Karyotype analysis of the same drosophila from different isofemale lines indicated that the same Drosophila from different places showed karyotypic variation which might be due to different geographical environment and evolutionary degree or interaction between the two factors. 展开更多
关键词 DROSOPHILA Drosophila melanogaster species group karyotype genetic relationships EVOLUTION
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Comparative study of the chromosome karyotypes of two species of grasshoppers in Megaulacobothrus Caudell (Orthoptera: Acridoidea) 被引量:1
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作者 林晨 王宁 +2 位作者 杜飞 能乃扎布 吴志毅 《Entomotaxonomia》 CSCD 北大核心 2012年第3期503-508,共6页
The chromosome karyotypes of Chorthippus (Megaulacobothrus) aethalinus (Zubovsky) and Ch. (M.) chinensis Tarbinsky were compared. Results show that the chromosome numbers of the two species fit 2n (♂) = 17 = ... The chromosome karyotypes of Chorthippus (Megaulacobothrus) aethalinus (Zubovsky) and Ch. (M.) chinensis Tarbinsky were compared. Results show that the chromosome numbers of the two species fit 2n (♂) = 17 = 16 + XO, in which three pairs of autosomal and sex chromosomes were terminal chromosomes, and the other five pairs of autosomes were metacentric chromosomes. These are diagnosis characters for Chorthippus. However, these two species can be distinguished by the different chromosome formula (CF) and the relative length (RL). The CF in Ch. (M.) aethalinus is K (2n, ♂) = 6m + 11t = 6L + 6M + 4S + XO, whereas that of Ch. (M.) chinensis is K (2n, ♂) = 6m + 11t = 6L + 8M + 2S + XO. In addition, we also found that the relative lengths of sex chromosomes in the two species were different from each other. The sex-chromosome of Ch. (M.) aethalinus is located at the fifth position and its relative length is 8.33% whereas that of Ch. (M.) chinensis is at the eighth position and its relative length is 5.53%. These results show that significantly different genetic features exist for the two species of Chorthippus. 展开更多
关键词 Chorthippus (Megaulacobothrus) aethalinus Chorthippus (Megaulacobothrus) chinensis karyotype
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A new species in the genus Hedotettix Bolivar(Orthoptera: Tetrigidae), including chromosome karyotype, from the western Yunnan Province in China
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作者 欧晓红 柳青 +1 位作者 郑哲民 李慧俊 《Entomotaxonomia》 CSCD 北大核心 2014年第3期166-170,共5页
A new species, Hedotettix nujiangensis Zheng sp. nov., is described. The chromosome complement of H. nujiangensis consists of 2n (♂) = 13. Sex determination is XO. All chromosomes are telocentric (T) and the sex ... A new species, Hedotettix nujiangensis Zheng sp. nov., is described. The chromosome complement of H. nujiangensis consists of 2n (♂) = 13. Sex determination is XO. All chromosomes are telocentric (T) and the sex chromosome is the fourth element in size. Type specimens are deposited at Southwest Forestry University. 展开更多
关键词 CAELIFERA C-band karyotype taxonomy
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Comparative study of the karyotypes of two species of grasshoppers in the genera Chorthippus Fieber and Euchorthippus Tarbinsky(Orthoptera: Arcypteridae)
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作者 林晨 王宁 +1 位作者 高书晶 能乃扎布 《Entomotaxonomia》 CSCD 2015年第1期1-7,共7页
The chromosome karyotypes of Chorthippus albomarginatus (De Geer) which represents the genus Chorthippus Fieber and Euchorthippus unicolor (Ikonnikov) which represents the genus Euchorthippus Tarbinsky were compar... The chromosome karyotypes of Chorthippus albomarginatus (De Geer) which represents the genus Chorthippus Fieber and Euchorthippus unicolor (Ikonnikov) which represents the genus Euchorthippus Tarbinsky were compared. The chromosome numbers for these two species fit 2n (♂) = 17 = 16 + XO, in which five pairs of autosomal and sex chromosomes are terminal chromosomes, and the other three pairs of autosomes are metacentric chromosomes. This similarity between the two genera indicates that they have a close phylogenetic relationship. However, these two species can be distinguished by their different chromosome formula (CF) and the relative sex chromosome length (RL). The CF in C. albomarginatus is K (2n,♂) = 6m + 11t = 8L + 4M + 4S + XO, whereas that ofE. unicolor is K (2n, ♂) = 6m + 11t = 8L + 6M + 2S + XO. The relative lengths of sex chromosomes in the two species are different. The sex-chromosome of C. albomarginatus is located at the ninth position and its relative length is 2.96% whereas that ofE. unicolor is at the eighth position and its relative length is 4.26%. These results show that significantly different genetic features exist for the two genera. 展开更多
关键词 Arcypterinae Chromosomes karyotype
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Chromosomes and Karyotypes of Three Seagrass Species of Hydrocharitaceae
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作者 杨文杰 都晶洁 +2 位作者 黄勃 王仁恩 张钰 《Agricultural Science & Technology》 CAS 2012年第6期1175-1178,共4页
[Objective] This study aimed to investigate the chromosomes and karyotypes of three seagrass species of hydrocharitaceae-Enhalus acoroides, Thalassia hemprichii and Halophila minor collected from Li’an Lagoon, Hainan... [Objective] This study aimed to investigate the chromosomes and karyotypes of three seagrass species of hydrocharitaceae-Enhalus acoroides, Thalassia hemprichii and Halophila minor collected from Li’an Lagoon, Hainan Province, China. [Method] The root-tips of E. acoroides, T. hemprichii and the axillary buds of H. minor were selected as the materials in this study. The conventional crushing method was used to prepare the slice specimens of chromosomes, and the karyotypes of the three species were analyzed. [Result] The chromosome numbers of E. acoroides, T. hemprichii and H. minor were 2n=18, 18, 28, respectively. The karyotype formulas were K (2n)=18= 12m+6sm, K(2n)=18=12m+6sm and K(2n)=28=16m+8sm+4st, respectively. According to the standard of Stebbins, the karyotypes of E. acoroides and T. hemprichii were 2A, and that of H. minor was 2B. There was no B chromosome and satellite in these three species. [Conclusion] According to the comparison on the karyotypes of this three species, E. acoroides and T. hemprichii are similar in karyotypes to each other, indicating that there is close, inter-relationship between E. acoroides and T. hemprichii. 展开更多
关键词 Enhalus acoroides Thalassia hemprichii Halophila minor CHROMOSOME karyotype
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A COMPARATIVE STUDY ON KARYOTYPES AND CHROMOSOME BANDING PATTERN OF THREE ODOR FROGS OF Rana
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作者 刘万兆 杨大同 《Zoological Research》 CAS CSCD 1994年第S1期166-172,203-204,共9页
The chromosomes of three odor frogs, Luetuosae- group of Rana were analyzed by conventional, as well as Obanding and silver staining techniques. The three species here examined all had 26 chromosome karyotypes encompa... The chromosomes of three odor frogs, Luetuosae- group of Rana were analyzed by conventional, as well as Obanding and silver staining techniques. The three species here examined all had 26 chromosome karyotypes encompassing 5 large and 8 small homologous pairs. Differences among them were found in gross shapes of chromosomes and positions of secondary constrictions. Generally speaking, karyotypes of R. andersonii and R. grahami resembled each other, while the karyotype of R. tiannanensis differed from the former two in several respects.Analyses of karyotypes by C-banding technique indicated that, centromeric areas of every chromosome and interstitial parts of some chromosomes of each species were hetero-chromatinized, and differences of distribution of heterochromatin were found among species. In early metaphase plates of R. andersonii, much more heterochromatinized areas were observed, and when it reached late metaphase, the numbers of heterochromatin sections in each chromosome pair reduced to a limited level, e. g. centromeres and a few interstitial parts.The active nucleolar organizer regions (NORs) were localized in long arms of pair No. 10, in connection with secondary constrictions for R. andersonii and R. grahami as in other odor frogs previously reported, but in the long arm of pair No. 6 for R. tiannanensis.The cytogenetic and taxonomic implications of the findings were discussed based on comparisons with each other, and with published literature. 展开更多
关键词 AMPHIBIA RANIDAE RANA karyotype Obanding pattern Ag-NORs
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Karyotype Differentiation in Newly Discovered Members of the Drosophila obscura Species Group from Yunnan,China 被引量:1
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作者 高建军 渡部英昭 +1 位作者 张亚平 青塚正志 《Zoological Research》 CAS CSCD 北大核心 2004年第3期236-241,共6页
We examined mitotic chromosomes of three newly found members of the Drosophila obscura species group,D.luguensis,D.dianensis and D.limingi from Yunnan and compared their karyotypes to those of respective related speci... We examined mitotic chromosomes of three newly found members of the Drosophila obscura species group,D.luguensis,D.dianensis and D.limingi from Yunnan and compared their karyotypes to those of respective related species.D.luguensis possessed a diploid number of 12 chromosomes,comprising 3 pairs of metacentrics (V-shaped),2 pairs of acrocentrics (rod-like) and 1 pair of micro-chromosomes (dot-like).Both the X and Y were metacentrics.D.dianensis and D.limingi possessed a diploid number of 10 chromosomes,comprising 1 pair of large V-shaped,1 pair of moderate-sized V-shaped,2 pairs of submetacentric (J-shaped) chromosomes,and 1 pairs of dot-like chromosomes,with their X chromosomes were J-shaped and Y chromosomes were short rod-like ones.Based upon the results of chromosomal comparisons,geographic information of the sinobscura subgroup,as well inter-specific phylogenetic relationship deduced elsewhere,D.luguensis was considered to retain an ancestral form of the karyotype within this subgroup.The present observations have also implied that D.sinobscura (2n=12:2V,1J,2R,1D) might have derived from a sub-lineage of a pre-“sinobscura-hubeiensis” lineage by pericentric inversion of moderate-sized metacentric autosomes and D.hubeiensis (2n=10:4V,1D) from another sub-lineage of the same lineage by centric fusion of 2 pairs of acrocentric autosomes.Similar chromosomal changes of centric fusion,centric fission and/or pericentric inversion might have occurred during the course of species divergences between D.dianensis and D.subsilvestris (2n=12:3V,2R,1D),an European member closely related to D.dianensis,and between D.limingi and D.tsukubaensis (2n=12:3V,2R,1D),an East Asian member near to D.limingi. 展开更多
关键词 Drosophila obscura species group karyotype differentiation China
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Karyotype Comparison and Analysis on Different Kinds of Onions 被引量:1
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作者 陈蕾 王军 《Agricultural Science & Technology》 CAS 2011年第12期1807-1809,共3页
[Objective] This study aimed to compare the similarities and dissimilarities in karyotypes of purple and white onions,so as to lay foundation for further studying its genetic improvement and breeding more onion variet... [Objective] This study aimed to compare the similarities and dissimilarities in karyotypes of purple and white onions,so as to lay foundation for further studying its genetic improvement and breeding more onion varieties.[Method] Sections of root-tip cells were prepared by normal wafer method.Photomicrography was adopted to produce the high-quality chromosome specimen.Finally,karyotype analysis was conducted using Adobe Photoshop.[Result] Chromosome karyotype analysis on the root-tip showed that the chromosome number of both purple and white onions was 2n=2x=16.Among the 16 chromosomes of both the onions,no satellite chromosome was found.By measuring and calculating,it was found that the karyotype of the studied white union belonged to the lowly evolutional 2A type,and its karyotype formula was 2n=2x=16=14 m +2St,with the karyotype asymmetry coefficient of 58.67%.No obvious centromere was observed in the sections of purple onion.[Conclusion] The karyotypes of white and purple unions are similar and we can infer from this fact that the reason of different characters between both the onions is not due to the chromosome aberration.This karyotype formula and asymmetrical karyotype coefficient have some reference values on the identification of onion variety resources. 展开更多
关键词 Purple onion White onion Chromosome sectioning karyotype
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Cytological Evaluation and Karyotype Analysis in Plant Germplasms of Elytrigia Desv. 被引量:9
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作者 MAO Pei-sheng HUANG Ying +3 位作者 WANG Xin-guo MENG Lin MAO Pei-cbun ZHANG Guo-fang 《Agricultural Sciences in China》 CAS CSCD 2010年第11期1553-1560,共8页
Elytrigia Desv. is widely distributed throughout the world and is represented with species of various levels of ploidy including diploids, tetraploids, hexaploids, octaploids, and decaploids. The distribution pattern ... Elytrigia Desv. is widely distributed throughout the world and is represented with species of various levels of ploidy including diploids, tetraploids, hexaploids, octaploids, and decaploids. The distribution pattern of these ploidy levels, however, is not well-defined. In this study, the levels of ploidy for 64 accessions of Elytrigia from 25 countries were determined with microscopic procedures. The results showed that accessions of E. intermedia and E. repens were grouped into three distinct levels of ploidy including diploids, tetraploids and hexaploids. For E. elongata, E. pontica, and E. caespitosa, it was found that two ploidy levels presented, and only one ploidy level was in those of E. hybrid, E. pycnantha, E. pungens, E. juncea, and E. alatavica. Karyotype analysis indicated that the karyotype formula of diploid, tetraploid and hexaploid of E. intermedia was 2n = 2x = 14 = 6m + 6sm + 2st, 2n = 4x = 28 = 2M + 10m + 16sm and 2n = 6x = 42 = 4M + 18m + 20sin, respectively. Furthermore, the karyotype formula of three germplasms in tetraploid of E. intermedia was 2n=4x=28 =2M+ 10m+ 16sm, 2n=4x=28=4M+22m (sat)+2sm and 2n=4x=28 =4M+ 12m+ 12sm (sat), which were not completely uniform. Therefore, it could be suggested that the studies about chromosome constitution would be helpful for the detail understanding of the diversity of germplasm resource in Elytrigia and promoting the utilization in the crop molecular breeding. 展开更多
关键词 Elytrigia Desv. PLOIDY EVALUATION karyotype analysis
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High molecular karyotype variation revealed in indigenous Elymus nutans in the Qinghai Plateau 被引量:10
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作者 Quanwen Dou Feng Yu +2 位作者 Yuan Li Yanyan Zhao Ruijuan Liu 《Plant Diversity》 SCIE CAS CSCD 北大核心 2017年第3期117-122,共6页
The karyotypes of 27 individuals of Elymus nutans from eight wild populations in the Qinghai Plateau were analyzed using sequential FISH and GISH. High FISH pattern polymorphism and karyotype variation were detected w... The karyotypes of 27 individuals of Elymus nutans from eight wild populations in the Qinghai Plateau were analyzed using sequential FISH and GISH. High FISH pattern polymorphism and karyotype variation were detected within and among populations. The chromosome variations were mainly characterized as repeat deletions and amplifications along with inter-genomic translocations. The chromosomes of the St and Y genomes demonstrated higher polymorphism than those of the H genome. Six different intergenomic translocations were identified in 33.3% of individuals; type Ⅰ and Ⅱ translocations were detected with higher frequency. Further analysis revealed that type Ⅰ and Ⅱ translocations were distributed in different geographic regions. The origin of high karyotype variation of E. nutans in the Qinghai plateau is further discussed. 展开更多
关键词 Elymus nutans karyotype variation Inter-genomic translocation
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Meiotic abnormalities in metaphase I human spermatocytes from infertile males: frequencies, chromosomes involved, and relationship with polymorphic karyotype and seminal parameters 被引量:5
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作者 Zaida Sarrate Francesca Vidal Joan Blanco 《Asian Journal of Andrology》 SCIE CAS CSCD 2014年第6期838-844,共7页
The aim of this study was to look in depth at the relationship between meiotic anomalies and male infertility, such as the determination of the chromosomes involved or the correlation with patient features. For this p... The aim of this study was to look in depth at the relationship between meiotic anomalies and male infertility, such as the determination of the chromosomes involved or the correlation with patient features. For this purpose, a total of 31 testicular tissue samples from individuals consulting for fertility problems were analyzed. Metaphase I cells were evaluated using a sequential methodology combining Leishman stained procedures and multiplex fluorescence in situ hybridization protocols. The number of chromosomal units and chiasmata count per bivalent were established and a hierarchical cluster analysis of the individuals was performed. The relationship of the seminogram and the karyotype over recombination were evaluated using Poisson regression models. Results obtained in this study show a significant percentage of infertile individuals with altered meiotic behavior, mostly specified as a reduction in chiasmata count in medium and large chromosomes, the presence of univalents, and the observation of tetraploid metaphases. Moreover, the number and the type of anomalies were found to be different between cells of the same individual, suggesting the coexistence of cell lines with normal meiotic behavior and cell lines with abnormalities. In addition, chromosomal abnormalities in metaphase I are significantly associated with oligozoospermia and/or polymorphic karyotype variants. 展开更多
关键词 chiasmata count human spermatocytes multiplex fluorescence in situ hybridization polymorphic karyotype seminalparameters
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Karyotype and cytogeography of the genus Heracleum (Apiaceae) in the Hengduan Mountains 被引量:2
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作者 Xian-Lan DENG Xing-Jin HE Wei-Lue HE Yun-Dong GAO Hai-Yan LIU Yu-Cheng ZHANG 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第4期273-285,共13页
In the present study, the karyotypes of 34 populations belonging to 11 species and one variety of Heracleum from the Hengduan Mountains in China were examined. Chromosome numbers and the karyotypes of three species (... In the present study, the karyotypes of 34 populations belonging to 11 species and one variety of Heracleum from the Hengduan Mountains in China were examined. Chromosome numbers and the karyotypes of three species (H. souliei, H. la'ngdoni, and H. wenchuanense) are reported for the first time, as are the karyotypes of H. moellendorffii and H. henryi (tetraploid). Populations of H. candicans, H. franchetii, and H. kingdoni in the Hengduan Mountains were found to consist of a mixture of diploid and tetraploid plants. Except for four species of Heracleum, namely H. candicans, H. franchetii, H. henryi, and H.kingdoni, which have both diploid and tetraploid karyotypes, all other species of Heracleum are were found to be diploid. All karyotypes were found to belong to the 2A type of Stebbins, with the exception ofH. candicans var. obtusifolium, which belongs to 2B, and H. hemsleyanum and H. franchetii (Mt. Dujuan, Daocheng, Sichuan, China), which belong to 1A. There was only a slight difference in the karyotype asymmetry index, which suggests a close kinship for species of Heracleum and that the entire phylogenetic development of Heracleum is relatively primitive. Species that exhibited advanced morphological features were also more advanced in karyotype structure, with the order ofkaryotype evolution being 1A→2A→2B. This phenomenon indicates that the species distributed in the Hengduan Mountains have not diverged completely and that the Hengduan Mountains are a relatively young and active area for the evolution of Heracleum. Polyploidization in Heracleum may be an important evolutionary mechanisms for some species, generating diversity. The biological attributes, distribution range, and the geological history of the genus have all played a part in accelerating the evolution through polyploidization or aneuploidization. It is known that as the distribution latitude of Heracleum decreases from north to south, the chromosome number, ploidy level, and asymmetry structure appear to increase. In the Hengduan Mountains, these tendencies are also evident. Finally, based on all the available cytogeographic data, we speculate that the more advanced tetraplont or aneuploid species of Heracleum in India may be derived from early diplont species that were distributed in the Caucasus region and Hengduan Mountains. The dispersal of Heracleum was from Eurasia to India, because this correlates with the emergence of the Himalayan Mountains through tectonic movement. Thus, the Hengduan Mountains are not only a center of diversity for Heracleurn, but also a center of active speciation in modern times. 展开更多
关键词 CYTOGEOGRAPHY EVOLUTION HERACLEUM karyotype polyploidization.
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