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Prenatal diagnosis of partial trisomy 21 associated with maternal balanced translocation 46xx der 21 t(21q;22q) with pericentric inversion of chromosome 9.  [cached]
Parmar R,Sira P
Journal of Postgraduate Medicine , 2003,
Abstract: This communication reports prenatal diagnosis of partial trisomy 21 resulting from balanced translocation (21q;22q) in a 36-year-old gravida 7, para 1 woman. The lady had only one living child and there was history of recurrent spontaneous first trimester abortions. Triple test was abnormal in the present conception. In addition, the woman had pericentric inversion of chromosome 9, a finding scarcely reported previously with carrier status in Indian literature. A few cytogeneticists consider this as a normal variant. However, many reports in the recent literature link pericentric inversion of chromosome 9 with infertility, recurrent abortions and a number of other abnormal conditions. A review of the relevant literature pertinent to the case is provided.
Focal cortical dysplasia and pericentric inversion of chromosome 9: a case report
Giancarlo DI GENNARO,Addolorata MASCIA,Liliana G. GRAMMALDO,Fabio SEBASTIANO
Journal of Neurological Sciences , 2004,
Abstract: A child affected by multiple dysmorphisms and behavioral disorders with pericentric inversion on chromosome 9 [46 XY inv 9 (p11q11)] is reported. In this patient, a focal cortical dysplasia in right temporal lobe was observed on magnetic resonance imaging of the brain. To our knowledge, this report is the first description of focal cortical dysplasia in a patient of an occidental country with pericentric inversion of chromosome. 9. The relationship between alterations localised on chromosome 9 and cerebral cortical organisation disorders is discussed.
A Rare Case of Pericentric Inversion, Inv (21) (p12;q22) in Repeated Pregnancy Loss: A Case Report
Naeimeh Tayebi,Hossain Khodaei
Oman Medical Journal , 2011,
Abstract: Pericentric inversions are among the most frequent chromosomal rearrangements with a frequency of 1-2 20There is no phenotypic effect in the majority of pericentric inversion heterozygote carriers, when it is a balanced rearrangement. However, miscarriages, infertility and/or chromosomally unbalanced offspring can be observed in carriers of a pericentric inversion. This is a case of pericentric inversion of one chromosome 21: inv (21) (p12; q22) in repeated pregnancy loss. A couple was referred for cytogenetic examination due to idiopathic miscarriages. The proband proved to be a carrier of chromosomal inversion and her partner’s karyotype was found to be normal. The karyotype of the proband is 46, xx, inv (21) (p12; q22). This abnormal karyotype is reported as a probable reason of miscarriage in the investigated couple. The risk of further miscarriages and the risk of a progeny with abnormal karyotype are rather high. Therefore, amniocenthesis for finding the chromosomal abnormality as a prenatal diagnosis are proposed for the patient if future pregnancy does not lead to miscarriage.
Homozygosity for Pericentric Inversions of Chromosome 9 in a Patient’s Parents with Stillbirth- Report of a New Case and Review of Literature
M Khaleghian,C Azimi
Iranian Journal of Public Health , 2006,
Abstract: Pericentric inversions of chromosome 9 are among the most frequent chromosomal rearrangement in human. A few cytogeneticists consider inversions of chromosome 9 as a normal variant. However, many reports in the recent literature link pericentric inversions of chromosome 9 with infertility, recurrent abortions, and a number of other abnormal conditions. We report a case of homozygosity pericentric inversions of chromosome 9 in a woman with 28- wk stillbirth. In this case, her both parents were heterozygotes for the inversions of chromosome 9.
Pericentric inversion of chromosome 9[inv(9)(p12q13)]: Its association with genetic diseases  [cached]
Rao Babu,Kerketta Lily,Korgaonkar Seema,Ghosh Kanjaksha
Indian Journal of Human Genetics , 2006,
Abstract: Background: The chromosomal polymorphism of short arms of acrocentric chromosomes and heterochromatin variation of Chromosomes 1, 9, 16 and Y have been reported in humans. The pericentric inversion of Chromosome 9 is commonly seen in normal humans and the frequency estimated to be 1 to 3% in general population and inherited in mendalian fashion or might occur spontaneously without any clinical significance. Aim: The aim of the study was to study the frequency of inv(9) and its clinical correlation with human genetic diseases. Materials and Methods:0 The chromosomal analysis using GTG-banding was carried out in 3,392 cases suspected with genetic diseases. Results: The pericentric inversion frequency of different chromosomes in our study was 1.24% and frequency of inv(9)(p12q13) was high (64.29%) compared to other pericentric inversions in our study. A high frequency (9.33%) of inv(9)(p12q13) was detected in children with dysmorphic features and congenital anomalies. Conclusion: As a high frequency of inv(9)(p12q13) detected in children with dysmorphic features, the inv(9) definitely have a role in the abnormal phenotype development. During inversion event there might be loss or suppression of euchromatin chromosome region and hence detailed chromosomal break point study is important to understand the clinical significance of the pericentric inversion of Chromosome 9.
Impact of pericentric inversion of Chromosome 9 [inv (9) (p11q12)] on infertility  [cached]
Mozdarani Hossein,Meybodi Anahita,Karimi Hamideh
Indian Journal of Human Genetics , 2007,
Abstract: Background : One of the frequent occurrences in chromosome rearrangements is pericentric inversion of the Chromosome 9; inv (9) (p11q12), which is consider to be the variant of normal karyotype. Although it seems not to correlate with abnormal phenotypes, there have been many controversial reports indicating that it may lead to abnormal clinical conditions such as infertility. The incidence is found to be about 1.98% in the general population. Materials and Methods : We investigated the karyotypes of 300 infertile couples (600 individuals) being referred to our infertility clinic using standard GTG banding for karyotype preparation. Results : The chromosomal analysis revealed a total of 15 (2.5%) inversions, among these, 14 male patients were inversion 9 carriers (4.69%) while one female patient was affected (0.33%). The incidence of inversion 9 in male patients is significantly higher than that of normal population and even than that of female patients (P< 0.05). Conclusions : This result suggests that inversion 9 may often cause infertility in men due to spermatogenic disturbances, which are arisen by the loops or acentric fragments formed in meiosis.
21三体征家庭的银染核仁形成区的研究
周宪庭,李立容,许碧珍
遗传 , 1980,
Abstract: 最近,发展了两种简单的染色技术:银氨法和N带。其中银染法可以反映核糖体RNA基因的活性,即:具有转录活性或已经转录过的,并具有残余蛋白质的核仁形成区被银染。 人类近端着丝点染色体有很高的变异频率,并且在这些染色体间常发现随体联合现象。据推测随体联合和近端着丝点染色体的不分离或易位有一定的关系。为了探明21三体征患者及其父母的核糖体RNA基因的功能及染色
The Kinetochore Is an Enhancer of Pericentric Cohesin Binding  [PDF]
Stewart A. Weber,Jennifer L. Gerton,Joan E. Polancic,Joseph L. DeRisi,Douglas Koshland,Paul C. Megee
PLOS Biology , 2012, DOI: 10.1371/journal.pbio.0020260
Abstract: The recruitment of cohesins to pericentric chromatin in some organisms appears to require heterochromatin associated with repetitive DNA. However, neocentromeres and budding yeast centromeres lack flanking repetitive DNA, indicating that cohesin recruitment occurs through an alternative pathway. Here, we demonstrate that all budding yeast chromosomes assemble cohesin domains that extend over 20–50 kb of unique pericentric sequences flanking the conserved 120-bp centromeric DNA. The assembly of these cohesin domains requires the presence of a functional kinetochore in every cell cycle. A similar enhancement of cohesin binding was also observed in regions flanking an ectopic centromere. At both endogenous and ectopic locations, the centromeric enhancer amplified the inherent levels of cohesin binding that are unique to each region. Thus, kinetochores are enhancers of cohesin association that act over tens of kilobases to assemble pericentric cohesin domains. These domains are larger than the pericentric regions stretched by microtubule attachments, and thus are likely to counter microtubule-dependent forces. Kinetochores mediate two essential segregation functions: chromosome movement through microtubule attachment and biorientation of sister chromatids through the recruitment of high levels of cohesin to pericentric regions. We suggest that the coordination of chromosome movement and biorientation makes the kinetochore an autonomous segregation unit.
The Kinetochore Is an Enhancer of Pericentric Cohesin Binding  [PDF]
Stewart A Weber,Jennifer L Gerton,Joan E Polancic,Joseph L DeRisi,Douglas Koshland,Paul C Megee
PLOS Biology , 2004, DOI: 10.1371/journal.pbio.0020260
Abstract: The recruitment of cohesins to pericentric chromatin in some organisms appears to require heterochromatin associated with repetitive DNA. However, neocentromeres and budding yeast centromeres lack flanking repetitive DNA, indicating that cohesin recruitment occurs through an alternative pathway. Here, we demonstrate that all budding yeast chromosomes assemble cohesin domains that extend over 20–50 kb of unique pericentric sequences flanking the conserved 120-bp centromeric DNA. The assembly of these cohesin domains requires the presence of a functional kinetochore in every cell cycle. A similar enhancement of cohesin binding was also observed in regions flanking an ectopic centromere. At both endogenous and ectopic locations, the centromeric enhancer amplified the inherent levels of cohesin binding that are unique to each region. Thus, kinetochores are enhancers of cohesin association that act over tens of kilobases to assemble pericentric cohesin domains. These domains are larger than the pericentric regions stretched by microtubule attachments, and thus are likely to counter microtubule-dependent forces. Kinetochores mediate two essential segregation functions: chromosome movement through microtubule attachment and biorientation of sister chromatids through the recruitment of high levels of cohesin to pericentric regions. We suggest that the coordination of chromosome movement and biorientation makes the kinetochore an autonomous segregation unit.
倒金字塔理论与21世纪中国老龄社会  [PDF]
李建新 ?
期刊检索-中国人口科学 , 2000,
Abstract: 如果说20世纪后半叶是人口增长的世纪,那么21世纪则是人口老龄化的世纪,人口大国的中国也不例外。中国人口年龄结构也正由传统的金字塔型(正三角形)转向倒金字塔式的老年型。本文从论述倒金字塔理论出发,强调了从理论上认识老龄社会的重要意义。并且尝试从人口学自身的角度出发,界定新的人口年龄构成划分的标准,重新审视未来的老龄社会,得出了有意义的结论。
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