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Sample records for chromosome 10q tetrasomy

  1. Chromosome 10q tetrasomy: First reported case

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    Blackston, R.D.; May, K.M.; Jones, F.D. [Emory Univ., Atlanta, GA (United States)] [and others

    1994-09-01

    While there are several reports of trisomy 10q (at least 35), we are not aware of previous cases of 10q tetrasomy. We present what we believe to be the initial report of such a case. R.J. is a 6 1/2 year old white male who presented with multiple dysmorphic features, marked articulation problems, hyperactivity, and developmental delays. He is the product of a term uncomplicated pregnancy. There was a normal spontaneous vaginal delivery with a birth weight of 6 lbs. 4oz. and length was 19 1/2 inch. Dysmorphic features include small size, an asymmetrically small head, low set ears with overfolded helixes, bilateral ptosis, downslanting eyes, right eye esotropia, prominent nose, asymmetric facies, high palate, mild pectus excavatum deformity of chest, and hyperextensible elbow joints. The patient is in special needs classes for mildly mentally handicapped students. Chromosome analysis at a resolution of 800 bands revealed a complex rearrangement of chromosomes 10 and 11. The segment 10q25.3 to q16.3 appears to be inverted and duplicated within the long arm of chromosome 10 at band q25.3 and the same segment of chromosome 10 is present on the terminal end of the short arm of chromosome 11. There is no visible loss of material from chromosome 11. Fluorescence in situ hybridization was performed with a chromosome 10 specific {open_quotes}paint{close_quotes} to confirm that all of the material on the abnormal 10 and the material on the terminal short arm of 11 was from chromosome 10. Thus, it appears that the segment 10q25.3 to q26.3 is present in four copies. Parental chromosome studies are normal. We compared findings which differ in that the case of 10q tetrasomy did not have prenatal growth deficiency, microphthalmia, cleft palate, digital anomalies, heart, or renal defects. Whereas most cases of 10q trisomy are said to have severe mental deficiency, our case of 10q tetrasomy was only mildly delayed. We report this first apparent cited case of 10q tetrasomy.

  2. Chromosome 10q Deletion del (10(q26.1q26.3 is Associated with Cataract

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    Yu-Tzu Chang

    2013-04-01

    Full Text Available Distal 10q deletion syndrome is an uncommon chromosomal disorder. Interstitial deletion involving bands 10q25–10q26.1 is extremely rare and few cases have been reported. The characteristic features are facial dysmorphisms, postnatal growth retardation, developmental delay, congenital heart disease, genitourinary anomalies, digital anomalies, and strabismus. We report for the first time a patient with de novo 10q interstitial deletion del (10(q26.1q26.3 and cataract.

  3. Aggressive juvenile polyposis in children with chromosome 10q23 deletion

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    Septer, Seth; Zhang, Lei; Lawson, Caitlin E; Cocjin, Jose; Attard, Thomas; Ardinger, Holly H

    2013-01-01

    Juvenile polyps are relatively common findings in children, while juvenile polyposis syndrome (JPS) is a rare hereditary syndrome entailing an increased risk of colorectal cancer. Mutations in BMPR1A or SMAD4 are found in roughly half of patients diagnosed with JPS. Mutations in PTEN gene are also found in patients with juvenile polyps and in Bannayan-Riley-Ruvalcaba syndrome and Cowden syndrome. Several previous reports have described microdeletions in chromosome 10q23 encompassing both PTEN...

  4. Chromosomal assignment of canine THADA gene to CFA 10q25

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    Dolf Gaudenz

    2008-06-01

    Full Text Available Abstract Background Chromosomal translocations affecting the chromosome 2p21 cluster in a 450 kb breakpoint region are frequently observed in human benign thyroid adenomas. THADA (thyroid adenoma associated was identified as the affected gene within this breakpoint region. In contrast to man tumours of the thyroid gland of dogs (Canis lupus familiaris constitute mainly as follicular cell carcinomas, with malignant thyroid tumours being more frequent than benign thyroid adenomas. In order to elucidate if the THADA gene is also a target of chromosomal rearrangements in thyroid adenomas of the dog we have physically mapped the canine THADA gene to canine chromosome 10. A PCR was established to screen a canine genome library for a BAC clone containing the gene sequence of canine THADA. Further PCR reactions were done using the identified BAC clone as a template in order to verify the corresponding PCR product by sequencing. Canine whole blood was incubated with colcemid in order to arrest the cultured cells in metaphases. The verified BAC DNA was digoxigenin labeled and used as a probe in fluorescence in situ hybridization (FISH. Ten well spread metaphases were examined indicating a signal on canine chromosome 10 on both chromatids. A detailed fine mapping was performed indicating the canine THADA gene locus on the q-arm of chromosome 10. Results The canine THADA gene locus was mapped on chromosome 10q25. Our mapping results obtained in this study following the previously described nomenclature for the canine karyotype. Conclusion We analysed whether the THADA gene locus is a hotspot of canine chromosomal rearrangements in canine neoplastic lesions of the thyroid and in addition might play a role as a candidate gene for a possible malignant transformation of canine thyroid adenomas. Although the available cytogenetic data of canine thyroid adenomas are still insufficient the chromosomal region to which the canine THADA has been mapped seems to be no

  5. Chromosome 4q;10q translocations; Comparison with different ethnic populations and FSHD patients

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    Zhang Cheng

    2002-08-01

    Full Text Available Abstract Background Facioscapulohumeral muscular dystrophy (FSHD is an autosomal dominant disorder characterized by the weakness of facial, shoulder-girdle and upper arm muscles. Most patients with FSHD have fewer numbers of tandem repeated 3.3-kb KpnI units on chromosome 4q35. Chromosome 10q26 contains highly homologous KpnI repeats, and inter-chromosomal translocation has been reported. Methods To clarify the influence on the deletion of the repeats, we surveyed three different ethnic populations and FSHD patients using the BglII/BlnI dosage test. Results The frequency of translocation in 153 Japanese, 124 Korean, 114 Chinese healthy individuals and 56 Japanese 4q35-FSHD patients were 27.5%, 29.8%, 19.3%, and 32.1%, respectively. The ratio of '4 on 10' (trisomy and quatrosomy of chromosome 4 was higher than that of '10 on 4' (nullsomy and monosomy of chromosome 4 in all populations. Conclusions The inter-chromosomal exchange was frequently observed in all four populations we examined, and no significant difference was observed between healthy and diseased groups.

  6. MGMT-Methylated Alleles Are Distributed Heterogeneously Within Glioma Samples Irrespective of IDH Status and Chromosome 10q Deletion.

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    Fontana, Laura; Tabano, Silvia; Bonaparte, Eleonora; Marfia, Giovanni; Pesenti, Chiara; Falcone, Rossella; Augello, Claudia; Carlessi, Nicole; Silipigni, Rosamaria; Guerneri, Silvana; Campanella, Rolando; Caroli, Manuela; Sirchia, Silvia; Bosari, Silvano; Miozzo, Monica

    2016-06-26

    Several molecular markers drive diagnostic classification, prognostic stratification, and/or prediction of response to therapy in patients with gliomas. Among them, IDH gene mutations are valuable markers for defining subtypes and are strongly associated with epigenetic silencing of the methylguanine DNA methyltransferase (MGMT) gene. However, little is known about the percentage of MGMT-methylated alleles in IDH-mutated cells or the potential association between MGMT methylation and deletion of chromosome 10q, which encompasses the MGMT locus. Here, we quantitatively assessed MGMT methylation and IDH1 mutation in 208 primary glioma samples to explore possible differences associated with the IDH genotype. We also explored a potential association between MGMT methylation and loss of chromosome 10q. We observed that MGMT methylation was heterogeneously distributed within glioma samples irrespective of IDH status suggesting an incomplete overlap between IDH1-mutated and MGMT-methylated alleles and indicating a partial association between these two events. Moreover, loss of one MGMT allele did not affect the methylation level of the remaining allele. MGMT was methylated in about half of gliomas harboring a 10q deletion; in those cases, loss of heterozygosity might be considered a second hit leading to complete inactivation of MGMT and further contributing to tumor progression. © 2016 American Association of Neuropathologists, Inc. All rights reserved.

  7. Two craniosynostotic syndrome loci, Crouzon and Jackson-Weiss, map to chromosome 10q23-q26

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    Li, X.; Lewanda, A.F.; Eluma, F. [Johns Hopkins Univ., Baltimore, MD (United States)] [and others

    1994-07-15

    Crouzon syndrome (MIM 123500) is a common autosomal dominant form of craniosynostosis with shallow orbits, ocular proptosis, and maxillary hypoplasia. Jackson-Weiss syndrome (MIM 123150) is another autosomal dominant craniosynostosis with highly variable phenotypic expression. Unlike Crouzon syndrome, Jackson-Weiss syndrome is associated with foot anomalies. The authors performed two point linkage and haplotype analyses using 13 dinucleotide repeat markers on chromosome 10, spanning a genetic distance of 108 cM. The Crouzon syndrome locus (CFD1) maps to the region of chromosome 10q2 with the tightest linkage to locus D10S205 (Z = 3.09, {theta} = 0.00). The Jackson-Weiss syndrome locus in the large Amish pedigree in which the condition was originally described was also linked to the chromosome 10q23-q26 region between loci D10S190 and D10S186. The D10S209 locus was most strongly linked (Z = 11.29, {theta} = 0.00). 29 refs., 2 figs., 2 tabs.

  8. Partial tetrasomy of chromosome 22q11.1 resulting from a supernumerary isodicentric marker chromosome in a boy with cat-eye syndrome.

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    Ko, Jung Min; Kim, Jun Bum; Pai, Ki Soo; Yun, Jun-No; Park, Sang-Jin

    2010-12-01

    The 22q11 region has been implicated in chromosomal rearrangements that result in altered gene dosage, leading to three different congenital malformation syndromes: DiGeorge syndrome, cat-eye syndrome (CES), and der(22) syndrome. Although DiGeorge syndrome is a common genomic disorder on 22q11, CES is quite rare, and there has been no report of Korean CES cases with molecular cytogenetic confirmation. In this study, we present the phenotypic and genetic characteristics of a 3-month-old boy with CES. Clinical findings included micropthalmia, multiple colobomata, and renal and genital anomalies. Cytogenetic analyses showed the presence of a supernumerary marker chromosome, which was identified as a bisatellited and isodicentric chromosome derived from an acrocentric chromosome. The results of array comparative genomic hybridization and fluorescence in situ hybridization studies confirmed the karyotype as 47,XY,+mar.ish idic(22)(q11.1) (D22S43+).arr 22q11.1(15,500,000-15,900,000)x4, resulting in a partial tetrasomy of 22q11.1. To the best of our knowledge, this is the first report in Korea of CES confirmed by cytogenetic and molecular cytogenetic analyses.

  9. Apparent late-onset Cockayne syndrome and interstitial deletion of the long arm of chromosome 10 (del(10)(q11.23q21.2)).

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    Fryns, J P; Bulcke, J; Verdu, P; Carton, H; Kleczkowska, A; Van den Berghe, H

    1991-09-01

    We present the history and data on a 24-year-old man with clinical and neurological symptoms similar to the findings in patients with late-onset Cockayne syndrome. Prometaphase chromosome studies documented an interstitial 10q211 deletion in all cells. This finding may indicate that the gene for late Cockayne syndrome is at 10q211.

  10. DMBT1, a new member of the SRCR superfamily, on chromosome 10q25.3-26.1 is deleted in malignant brain tumours

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    Mollenhauer, J; Wiemann, S; Scheurlen, W

    1997-01-01

    Loss of sequences from human chromosome 10q has been associated with the progression of human cancer. Medulloblastoma and glioblastoma multiforme are the most common malignant brain tumours in children and adults, respectively. In glioblastoma multiforme, the most aggressive form, 80% of the tumo......Loss of sequences from human chromosome 10q has been associated with the progression of human cancer. Medulloblastoma and glioblastoma multiforme are the most common malignant brain tumours in children and adults, respectively. In glioblastoma multiforme, the most aggressive form, 80......% of the tumours show loss of 10q. We have used representational difference analysis to identify a homozygous deletion at 10q25.3-26.1 in a medulloblastoma cell line and have cloned a novel gene, DMBT1, spanning this deletion. DMBT1 shows homology to the scavenger receptor cysteine-rich (SRCR) superfamily...

  11. Prenatal diagnosis of sub-microscopic partial trisomy 10q using chromosomal microarray analysis in a phenotypically abnormal fetus with normal karyotype.

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    Browne, P C; Adam, S; Badr, M; Brooks, C R; Edwards, J; Walker, P; Mohamed, S; Gregg, A R

    2016-05-17

    Partial trisomy of the 10q region was originally reported in 1979 [1]. For 25 years, the diagnosis was made microscopically based on large, visible insertions in the region identified by karyotype analysis. Previous case reports have included both unbalanced translocations and large duplications/insertions in the 10q region [2]. Probands with partial trisomy 10q syndrome often have an abnormal phenotype that may include developmental delay [3-5], craniofacial abnormalities [3, 5], talipes (clubfoot) [2], microcephaly [2-4], or congenital heart disease [2-6]. Prenatal diagnoses by karyotype have been made following ultrasound diagnosis of sacrococcygeal teratoma [7], renal pyelectasis [3, 8-10], and other fetal abnormalities [4]. In this case, we report the first prenatal diagnosis of partial trisomy 10q (10q22.3-10q23.2) with a normal karyotype and an abnormal chromosomal microarray analysis (CMA). This is the smallest copy number variant (CNV) (7.5 Mb) in the 10q22.3-10q23.2 regions yet reported.

  12. Two craniosynostotic syndrome loci, Crouzon and Jackson-Weiss, map to chromosome 10q23-q26

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    Elumfa, F.; Lewanda, A.; Li, X. [Johns Hopkins Univ., Baltimore, MD (United States)] [and others

    1994-09-01

    Craniosynostosis is a common malformation consisting of premature fusion of skull bones leading to abnormal head shape and, in severe cases, increased intracranial pressure. Crouzon (CFD1) and Jackson-Weiss syndromes (JWS) are two distinct autosomal dominant craniosynostotic conditions with ocular proptosis and maxillary hypoplasia. In the former condition, the proptosis tends to be more severe and is due to shallow orbits. Unlike CFD1, JWS is associated with foot anomalies and highly variable phenotypic expression. We performed two point linkage and haplotype analyses with 15 markers on chromosome 10, spanning a genetic distance of 108 cM. The CFD1 locus maps to the chromosome 10q23-26 region with tightest linkage to D10S205 (Z=3.09, {theta}=0.00, 19 meioses). The JWS locus (originally described in this family) was also linked to this region in an 18 cM interval between D10S190 and D10S186. The D10S209 locus was most strongly linked (Z=11.29, {theta}=0.00, 40 meioses). All of the markers had recombinants with at least one of the conditions. Regional candidate genes implicated in craniofacial and limb development include HOX11, PAX2, ZNF32, and RBP3. These disorders may be allelic, but our data raised the possibility of genetic heterogeneity. As we gather more families, we will find evidence for or against the presence of genetically distinct forms of both syndromes. Isolation of the craniosynostotic gene(s) on chromosome 10 will be important for accurate diagnosis of these disorders and identification of genetic factors involved in craniofacial development.

  13. Chromosome aberrations involving 10q22: report of three overlapping interstitial deletions and a balanced translocation disrupting C10orf11

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    Tzschach, Andreas; Bisgaard, Anne-Marie; Kirchhoff, Maria

    2010-01-01

    and hypotonia. We also report on the results of breakpoint analysis by array painting in a mentally retarded patient with a balanced chromosome translocation 46,XY,t(10;13)(q22;p13)dn. The breakpoint in 10q22 was found to disrupt C10orf11, a brain-expressed gene in the common deleted interval of patients 1...

  14. Search for a shared segment on chromosome 10q26 in patients with bipolar affective disorder or schizophrenia from the Faroe Islands

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    Ewald, Henrik; Flint, Tracey J; Jorgensen, Tove H

    2002-01-01

    Previous linkage studies have suggested a new locus for bipolar affective disorder and possibly also for schizophrenia on chromosome 10q26. We searched for allelic association and chromosome segment and haplotype sharing on chromosome 10q26 among distantly related patients with bipolar affective...... disorder or schizophrenia and controls from the relatively isolated population of the Faroe Islands by investigating 22 microsatellite markers from a 35 cM region. We used a combined approach with both assumption free tests and tests based on genealogical relationships. The 6.5 cM region between D10S1230...... and D10S2322, which has been implied in previous linkage analyses, received some support. A search for segment sharing yielded empirical P-values around 0.02 among patients with bipolar affective disorder and around 0.03 for patients with schizophrenia. For both disorders combined allelic association...

  15. Search for a shared segment on chromosome 10q26 in patients with bipolar affective disorder or schizophrenia from the Faroe Islands

    DEFF Research Database (Denmark)

    Ewald, Henrik; Flint, Tracey J; Jorgensen, Tove H

    2002-01-01

    Previous linkage studies have suggested a new locus for bipolar affective disorder and possibly also for schizophrenia on chromosome 10q26. We searched for allelic association and chromosome segment and haplotype sharing on chromosome 10q26 among distantly related patients with bipolar affective...... and D10S2322, which has been implied in previous linkage analyses, received some support. A search for segment sharing yielded empirical P-values around 0.02 among patients with bipolar affective disorder and around 0.03 for patients with schizophrenia. For both disorders combined allelic association...... yielded empirical P-values around 0.003 at marker D10S1723. A haplotype data mining approach supported haplotype sharing in this region. In another, more distal, 11.5 cM region between markers D10S214 and D10S505, which has received support in previous linkage studies, increased haplotype sharing...

  16. A chromosome 10 variant with a 12 Mb inversion [inv(10)(q11.22q21.1)] identical by descent and frequent in the Swedish population.

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    Entesarian, Miriam; Carlsson, Birgit; Mansouri, Mahmoud Reza; Stattin, Eva-Lena; Holmberg, Eva; Golovleva, Irina; Stefansson, Hreinn; Klar, Joakim; Dahl, Niklas

    2009-03-01

    We identified a paracentric inversion of chromosome 10 [inv(10)(q11.22q21.1)] in 0.20% of Swedish individuals (15/7,439) referred for cytogenetic analysis. A retrospective analysis of 8,896 karyotypes from amniocenteses in Sweden revealed a carrier frequency of 0.079% (7/8,896) for the inversion. Cloning and detailed analysis of the inversion breakpoint regions show enrichment for interspersed repeat elements and AT-stretches. The centromeric breakpoint coincides with that of a predicted inversion from HapMap data, which suggests that this region is involved in several chromosome 10 variants. No known gene or predicted transcript are disrupted by the inversion which spans approximately 12 Mb. Carriers from four non-related Swedish families have identical inversion breakpoints and haplotype analysis confirmed that the rearrangement is identical by descent. Diagnosis was retrieved in 6 out of the 15 carriers referred for cytogenetic analysis. No consistent phenotype was found to be associated with the inversion. Our study demonstrates that the inv(10)(q11.22q21.1) is a rare and inherited chromosome variant with a broad geographical distribution in Sweden. 2009 Wiley-Liss, Inc.

  17. Analysis of Prostate Cancer Susceptibility Variants in South African Men: Replicating Associations on Chromosomes 8q24 and 10q11

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    Pedro Fernandez

    2015-01-01

    Full Text Available Genome-wide association studies (GWAS have implicated single nucleotide polymorphisms (SNPs on chromosomes 2p15, 6q25, 7p15.2, 7q21, 8q24, 10q11, 10q26, 11q13, 17q12, 17q24, 19q13, and Xp11, with prostate cancer (PCa susceptibility and/or tumour aggressiveness, in populations of African, European, and Asian ancestry. The objective of this study was to confirm these associations in South African Mixed Ancestry and White men. We evaluated 17 prioritised GWAS SNPs in South African cases (331 Mixed Ancestry and 155 White and controls (178 Mixed Ancestry and 145 White. The replicated SNP associations for the different South African ethnic groups were rs7008482 (8q24 (p=2.45×10-5, rs6983267 (8q24 (p=4.48×10-7, and rs10993994 (10q11 (p=1.40×10-3 in Mixed Ancestry men and rs10993994 (p=1.56×10-9 in White men. No significant associations were observed for the analyses stratified by disease aggressiveness in the individual and the combined population group analysis. The present study demonstrates that a number of known PCa susceptibility variants may contribute to disease susceptibility in South African men. Larger genetic investigations extended to other South African population groups are warranted to confirm the role of these and other SNPs in disease susceptibility.

  18. The gene for Crouzon craniofacial dysostosis maps to a 7 centiMorgan region on chromosome 10q in three unrelated kindreds

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    Ehrlich, G.D.; Preston, R.A.; Aston, C.A. [Univ. of Pittsburgh, PA (United States)] [and others

    1994-09-01

    Crouzon craniofacial dysostosis (CFD, M.I.M. number 123500) is an autosomal dominant disorder of craniofacial development with complete penetrance and variable expressivity that is characterized by premature craniosynostosis, maxilary hypoplasia, and shallow orbits. We recently mapped CFD to a 21 centiMorgan (cM) region of chromosome 10q25-q26 in two unrelated families from North America. We now report the confirmation of this locus using a third large CFD kindred from South America and describe a refinement of the CFD gene map position. A recombination was observed in two members of the Argentinean kindred at marker D10S209, thereby redefining the centromeric limit of the CFD locus. In addition, a newly available Genethon microsatellite marker, D10S587, which maps between D10S216 and D10S209, proved to be informative for the original family and a recombination was observed at this marker in an unaffected family member, redefining the telomeric limit of the Crouzon syndrome locus. The finding of these obligate recombinants reduces the candidate region for the CFD gene locus to 7 cM. Multipoint linkage analysis (LINKAGE (ver 5.1)) carried out on the three pedigrees produced a maximal LOD score of 12.33 at a locus approximately 2 cM telomeric to D10S209. These findings suggest that CFD is a genetically homogeneous disorder caused by mutations in a gene located on chromosome 10q.

  19. Tetrasomy Y by structural rearrangement: clinical report.

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    DesGroseilliers, Martin; Lemyre, Emmanuelle; Dallaire, Louis; Lemieux, Nicole

    2002-09-01

    Poly-Y karyotypes, except for 47,XYY, are rare events in humans. For instance, Y chromosome tetrasomy has been reported 10 times, 2 of which were by structural rearrangement. We present a 2-year-and-4-month-old boy who was referred for cytogenetic assessment because of global psychomotor delay. The GTG- and CBG-banded karyotypes on PHA-stimulated lymphocytes showed two cell populations, one of them contained two identical isodicentric Y chromosomes, which was seen in 93% of metaphases analyzed, and a 45,X cell line (7%). This was confirmed by FISH with probes DYZ3 (recognizing the centromeric region of the Y chromosome), 91H4.5 (recognizing Yp11.2), and DYZ1 (recognizing Y heterochromatin in Yq12). The breakpoint has occurred near the telomeric end of the heterochromatic region. Therefore, the karyotype is mos 47,X,idic(Y)(q12)x2[123]/45,X[9]. This is the second time that such a karyotype has been reported. This chromosomal anomaly was formed most likely by a U-type exchange. Clinical features included speech delay, short stature, brachycephaly, large ears, bilateral epicanthal folds, hypertelorism, delayed teeth eruption, bilateral radio-ulnar synostosis, bilateral fifth finger clinodactyly, normal external genitalia, and impulsive behavior. The father had normal phenotype and karyotype. A review of the tetrasomy Y patients is presented. All patients with Y chromosome tetrasomy exhibit some degree of mental retardation, various skeletal abnormalities, and facial dysmorphism. Nevertheless, the correlation between karyotype and phenotype is not yet well defined since few cases have been reported. This clinical report will be helpful in defining the phenotypic range associated with tetrasomy Y. Copyright 2002 Wiley-Liss, Inc.

  20. Mosaic tetrasomy 20p associated with osteoporosis and recurrent fractures.

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    Maziad, Asmaa S Abu; Seaver, Laurie H

    2015-07-01

    Tetrasomy 20p is a very rare chromosome abnormality, with only two single cases previously reported in the literature, both fetuses with multiple congenital anomalies, osteopenia, and fractures. We report on the first case of mosaic tetrasomy 20p in a 13-year-old male. Amniocentesis karyotype showed mosaicism (73% of cells) for a supernumerary marker chromosome, an isodicentric chromosome 20p. At birth, cord blood karyotype was normal in all cells but uroepithelial cells showed the marker chromosome in 30% of cells analyzed. Chromosomal single nucleotide polymorphism (SNP) microarray using buccal cells confirmed the previous result with mosaicism estimated at 59% of cells. His course has been complicated by profound osteoporosis with recurrent nontraumatic fractures and vertebral compression leading to significant disability. This report describes the phenotype and evaluation of mosaic pure tetrasomy 20p syndrome and compares to nonmosaic tetrasomy 20p and trisomy 20p syndromes, both of which have been previously reported in association with osteopenia and fractures. The pathophysiology of osteoporosis in tetrasomy 20p is unknown. We hypothesize that overexpression of bone morphogenetic protein 2 may be the underlying mechanism of osteoporosis and recurrent fractures. © 2015 Wiley Periodicals, Inc.

  1. Assignment of the 5HT7 receptor gene (HTR7) to chromosome 10q and exclusion of genetic linkage with Tourette syndrome

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    Gelernter, J.; Rao, P.A.; Pauls, D.L. [Yale Univ. School of Medicine, West Haven, CT (United States)] [and others

    1995-03-20

    A novel serotonin receptor designated 5HT7 (genetic locus HTR7) was cloned in 1993. This receptor has interesting properties related to ligand affinity and CNS distribution that render HTR7 a very interesting candidate gene for neuropsychiatric disorders. We mapped this gene, first by physical methods and then by genetic linkage. First, we made a tentative assignment to chromosome 10, based on hybridization of an HTR7 probe to a Southern blot of DNA from somatic cell hybrids. We then identified a genetic polymorphism at the HTR7 locus. We identified one extended pedigree where the polymorphism segregated. Using the LEPED computer program for pairwise linkage analysis, we confirmed the assignment of the gene to chromosome 10, specifically 10q21-q24, based on a lod score of 5.37 at 0% recombination between HTR7 and D10S20 (a chromosome 10 reference marker). Finally, we excluded genetic linkage between this locus and Tourette syndrome under a reasonable set of assumptions. 15 refs., 1 fig., 1 tab.

  2. High-density fine-mapping of a chromosome 10q26 linkage peak suggests association between endometriosis and variants close to CYP2C19

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    Painter, Jodie N.; Nyholt, Dale R.; Morris, Andrew; Zhao, Zhen Z.; Henders, Anjali K.; Lambert, Ann; Wallace, Leanne; Martin, Nicholas G.; Kennedy, Stephen H.; Treloar, Susan A.; Zondervan, Krina T.; Montgomery, Grant W.

    2011-01-01

    Objective To refine a previously reported linkage peak for endometriosis on chromosome 10q26, and conduct follow-up analyses and a fine-mapping association study across the region to identify new candidate genes for endometriosis. Design Case-control study. Setting Academic research. Subject(s) Cases = 3,223 women with surgically confirmed endometriosis; Controls = 1,190 women without endometriosis and 7,060 population samples. Intervention(s) Analysis of 11,984 SNPs on chromosome 10. Main outcome measure(s) Allele frequency differences between cases and controls. Results Linkage analyses on families grouped by endometriosis symptoms (primarily subfertility) provided increased evidence for linkage (logarithm of odds (LOD) score = 3.62) near a previously reported linkage peak. Three independent association signals were found at 96.59 Mb (rs11592737, P=4.9 × 10−4), 105.63 Mb (rs1253130, P=2.5 × 10−4) and 124.25 Mb (rs2250804, P=9.7 × 10−4). Analyses including only samples from linkage families supported the association at all three regions. However, only rs11592737 in the cytochrome P450 subfamily C (CYP2C19) gene was replicated in an independent sample of 2,079 cases and 7060 population controls. Conclusion(s) The role of the CYP2C19 gene in conferring risk for endometriosis warrants further investigation. PMID:21497341

  3. Polycystic kidney disease gene in the Lewis polycystic kidney rat is mapped to chromosome 10q21–q26

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    Yengkopiong JP

    2012-08-01

    Full Text Available Jada Pasquale YengkopiongDr John Garang Memorial University of Science and Technology, Faculty of Science and Technology, Bor, Republic of South SudanBackground: Polycystic kidney disease (PKD is a life-threatening disorder that affects the kidneys of millions of people across the world. The disease is normally inherited, but it can also be acquired, and leads to development of many cysts in the renal nephrons. In this study, the aim was to characterize PKD in the Lewis polycystic kidney (LPK rat, the newest model for human PKD.Methods: Mating experiments were performed between male LPK rats with PKD and female Brown Norway and Wistar Kyoto rats without PKD to raise second filial (F2 and backcross 1 (BC1 progeny, respectively. Rats that developed PKD were identified. Histological examination of the kidneys and liver was performed. Liver tissue samples were collected from each rat and used to extract DNA. The extracted DNA was amplified, and mapping and linkage analyses were performed to identify the quantitative trait locus that controlled the disease phenotypes.Results: It was established that the disease was controlled by a recessive mutation in a single gene (F2: PKD = 42, non-PKD = 110, χ2 = 0.53; BC1: PKD = 67, non-PKD = 72, χ2 = 0.18, P > 0.05 and that the disease was inherited as autosomal recessive polycystic kidney disease (ARPKD. The rats with PKD developed larger fluid-filled cystic kidneys, higher systolic blood pressure, and anemia. However, there were no extrarenal cysts and no pup deaths. Mapping studies and linkage analyses associated the disease phenotypes in both the F2 and BC1 rats to chromosome 10q21–q26, giving a maximum LOD score of 7.9 (P = 0.00001 between peak markers D10Rat180 and D10Rat26.Conclusion: The quantitative trait locus on chromosome 10q21–q26 does not contain the Pkhd-1 gene, and it is different from quantitative trait loci that control ARPKD in other murine models. The candidate genes located in the

  4. Inv dup del(10q: Identification by fluorescence in situ hybridization and array comparative genomic hybridization in a fetus with two concurrent chromosomal rearrangements

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    Chih-Ping Chen

    2012-06-01

    Conclusion: A de novo inv dup del(10q can be associated with a concurrent de novo balanced reciprocal translocation and should be differentiated from an unbalanced CCR by molecular cytogenetic techniques.

  5. Prenatal diagnosis of mosaic tetrasomy 18p

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    Chih-Ping Chen

    2012-12-01

    Conclusion: There is cytogenetic discrepancy between amniocytes and cord blood lymphocytes in prenatally detected mosaic tetrasomy 18p. Interphase FISH on uncultured amniocytes has the advantage of rapid confirmation of low-level mosaicism for tetrasomy 18p at amniocentesis.

  6. The "cat eye syndrome": dicentric small marker chromosome probably derived from a no.22 (tetrasomy 22pter to q11) associated with a characteristic phenotype. Report of 11 patients and delineation of the clinical picture.

    Science.gov (United States)

    Schinzel, A; Schmid, W; Fraccaro, M; Tiepolo, L; Zuffardi, O; Opitz, J M; Lindsten, J; Zetterqvist, P; Enell, H; Baccichetti, C; Tenconi, R; Pagon, R A

    1981-01-01

    Eleven patients with the so-called Cat Eye syndrome are reported including a more detailed description of the original cases reported by Schmid and Fraccaro. All cases had, in addition to a normal karyotype, a small extra G-like chromosome which appeared to be an isochromosome for the juxtacentromeric region (pter to q11) of an acrocentric chromosome. None were mosaics. Clinical findings and further cytogenetic studies in a few cases suggest that these markers probably derive from a No. 22 chromosome. Characteristic features of the Cat Eye syndrome in these 11 patients and those reviewed from the literature are: ocular coloboma which may involve the iris, choroid and/or optic nerve, preauricular skin tags and/or pits which are probably the most consistent feature, congenital heart defect, anal atresia with a fistula, renal malformations such as unilateral absence, unilateral or bilateral hypoplasia, and cystic dysplasia, and antimongoloid position of eyes. Intelligence is usually low-normal, although moderate retardation is also seen. There is great variability in the clinical findings ranging from near normal to lethal malformations. Less frequent, but also characteristic findings are: microphthalmia, microtia with atresia of the external auditory canal, intrahepatic or extrahepatic biliary atresia and malrotation of the gut. Direct transmission of the marker from one generation to the other was observed in both sexes. In those families, there was considerable variability in the clinical findings between affected family members. These cases show that there is a bias of ascertainment for patients who have the more striking malformations, especially those with ocular coloboma and anal atresia, a combination which appears to be present in only a minority of cases. Many mildly affected patients probably remain undetected. It is proposed that the term Cat Eye syndrome should be applied only to cases with trisomy or tetrasomy of not more than 22pter to q11 and without

  7. cDNA cloning, expression profile and genomic structure of a novel human transcript on chromosome 10q24, and its analyses as a candidate gene for infantile onset spinocerebellar ataxia.

    Science.gov (United States)

    Nikali, Kaisu; Saharinen, Juha; Peltonen, Leena

    2002-10-16

    In our search for the disease gene underlying autosomally recessively inherited infantile onset spinocerebellar ataxia (IOSCA), we identified an expressed sequence tag cluster representing a previously uncharacterized transcript in the restricted genomic sequence covering the IOSCA locus on chromosome 10q24, and for mutation analyses in IOSCA patients isolated the corresponding novel human cDNA, C10orf6. Multiple tissue cDNA and Northern analyses showed that this gene is ubiquitously expressed, with expression levels highest in the skeletal muscle and less abundant in the brain, liver, and heart than in other tissues examined. C10orf6 consists of 20 exons forming a 7.3 kb cDNA which is capable of encoding a 1173 amino acid polypeptide and possesses orthologues in other mammals. Sequencing of RT and genomic PCR products of the gene revealed no alterations in IOSCA patients when compared to control subjects, and neither could differences be detected in expression levels between patient and control brain RNA samples, thus excluding mutation(s) in this novel gene as causative for IOSCA. However, this study facilitates future investigations on both the role of C10orf6 gene product in human cells as well as its possible involvement in the pathogenesis of other hereditary diseases mapped to chromosome 10q24.

  8. Genome-wide association study identifies chromosome 10q24.32 variants associated with arsenic metabolism and toxicity phenotypes in Bangladesh.

    Directory of Open Access Journals (Sweden)

    Brandon L Pierce

    Full Text Available Arsenic contamination of drinking water is a major public health issue in many countries, increasing risk for a wide array of diseases, including cancer. There is inter-individual variation in arsenic metabolism efficiency and susceptibility to arsenic toxicity; however, the basis of this variation is not well understood. Here, we have performed the first genome-wide association study (GWAS of arsenic-related metabolism and toxicity phenotypes to improve our understanding of the mechanisms by which arsenic affects health. Using data on urinary arsenic metabolite concentrations and approximately 300,000 genome-wide single nucleotide polymorphisms (SNPs for 1,313 arsenic-exposed Bangladeshi individuals, we identified genome-wide significant association signals (P<5×10(-8 for percentages of both monomethylarsonic acid (MMA and dimethylarsinic acid (DMA near the AS3MT gene (arsenite methyltransferase; 10q24.32, with five genetic variants showing independent associations. In a follow-up analysis of 1,085 individuals with arsenic-induced premalignant skin lesions (the classical sign of arsenic toxicity and 1,794 controls, we show that one of these five variants (rs9527 is also associated with skin lesion risk (P = 0.0005. Using a subset of individuals with prospectively measured arsenic (n = 769, we show that rs9527 interacts with arsenic to influence incident skin lesion risk (P = 0.01. Expression quantitative trait locus (eQTL analyses of genome-wide expression data from 950 individual's lymphocyte RNA suggest that several of our lead SNPs represent cis-eQTLs for AS3MT (P = 10(-12 and neighboring gene C10orf32 (P = 10(-44, which are involved in C10orf32-AS3MT read-through transcription. This is the largest and most comprehensive genomic investigation of arsenic metabolism and toxicity to date, the only GWAS of any arsenic-related trait, and the first study to implicate 10q24.32 variants in both arsenic metabolism and arsenical

  9. Sperm FISH analysis of a 44,X,der(Y),t(Y;15)(q12;q10)pat,rob(13;14)(q10;q10)mat complex chromosome rearrangement.

    Science.gov (United States)

    Ferfouri, F; Boitrelle, F; Clement, P; Molina Gomes, D; Selva, J; Vialard, F

    2014-06-01

    Complex chromosome rearrangements (CCR) with two independent chromosome rearrangements are rare. Although CCRs lead to high unbalanced gamete rates, data on meiotic segregation in this context are scarce. A male patient was referred to our clinic as part of a family screening programme prompted by the observation of a 44,X,der(Y),t(Y;15)(q12;q10)pat,rob(13;14)(q10;q10)mat karyotype in his brother. Karyotyping identified the same CCR. Sperm FISH (with locus-specific probes for the segments involved in the translocations and nine chromosomes not involved in both rearrangements) was used to investigate the rearrangements meiotic segregation products and establish whether or not an inter-chromosomal effect was present. Sperm nuclear DNA fragmentation was also evaluated. For rob(13;14) and der(Y), the proportions of unbalanced products were, respectively, 26.4% and 60.6%. Overall, 70.3% of the meiotic segregation products were unbalanced. No evidence of an inter-chromosomal effect was found, and the sperm nuclear DNA fragmentation rate was similar to our laboratory's normal cut-off value. In view of previously published sperm FISH analyses of Robertsonian translocations (and even though the mechanism is still unknown), we hypothesise that cosegregation of der(Y) and rob(13;14) could modify rob(13;14) meiotic segregation. © 2013 Blackwell Verlag GmbH.

  10. [Anesthetic management of a patient with 15q tetrasomy for dental treatment].

    Science.gov (United States)

    Hase, Yuri; Kemekura, Nobuhito; Nitta, Yukie; Fujisawa, Toshiaki

    2017-05-23

    15q tetrasomy is a chromosomal abnormality that is a part of the heterogeneous group of extra structurally abnormal chromosomes. This syndrome is characterized by epilepsy, central hypotonia, developmental delay and intellectual disability, and autistic behavior. This is the first report of the anesthetic management of a patient with this syndrome. We administered general anesthesia for dental treatment in a patient with 15q tetrasomy. Appropriate planning for the prevention of complications such as seizures and hypotonia, and for delayed emergence from anesthesia, is required. Specifically, choosing short-acting drugs that do not induce seizures, together with suitable monitoring, resulted in successful anesthetic management of the patient with 15q tetrasomy. Copyright © 2017. Publicado por Elsevier Editora Ltda.

  11. Tetrasomy 18p in a male dysmorphic child in southeast Turkey

    Indian Academy of Sciences (India)

    Clinical examinations revealed dysmorphic face pattern with prominent forehead, microcephaly with wide mouth, pos- teriorly rotated low-set ears, severe mental retardation, autistic behaviour, impaired speech, and inability to walk. Keywords. tetrasomy 18p; isochromosome; marker chromosome; i(18p); human genetics.

  12. Partial proximal trisomy 10q syndrome: a new case.

    Science.gov (United States)

    Nucaro, A; Faedda, A; Cao, A; Boccone, L

    2002-01-01

    We report a case of partial proximal trisomy of the long arm of chromosome 10 confirmed by fluorescence in situ hibridization (FISH) performed with whole chromosome 10 specific painting and specific yac clones. The phenotypic findings, compared to those found in other published cases with the same karyotype, support the recognition of a distinctive partial proximal trisomy 10q syndrome (10q11-->q22).

  13. A 1.5-Megabase Yeast Artificial Chromosome Contig from Human Chromosome 10q11.2 Connecting Three Genetic Loci (RET, D10S94, and D10S102) Closely Linked to the MEN2A Locus

    National Research Council Canada - National Science Library

    Terry C. Lairmore; Shenshen Dou; James R. Howe; David Chi; Katrin Carlson; Rosalie Veile; Santosh K. Mishra; Samuel A. Wells; Helen Donis-Keller

    1993-01-01

    ...) and medullary thyroid carcinoma (MTC1) familial cancer syndromes. We have constructed a 1.5-megabase contig consisting of six genomic yeast artificial chromosome clones which include these loci and define their physical order...

  14. Relatives with opposite chromosome constitutions, rec(10)dup(10p)inv(10)(p15.1q26.12) and rec(10)dup(10q)inv(10)(p15.1q26.12), due to a familial pericentric inversion.

    Science.gov (United States)

    Ciuladaite, Zivile; Preiksaitiene, Egle; Utkus, Algirdas; Kučinskas, Vaidutis

    2014-01-01

    Large pericentric inversions in chromosome 10 are rare chromosomal aberrations with only few cases of familial inheritance. Such chromosomal rearrangements may lead to production of unbalanced gametes. As a result of a recombination event in the inversion loop, 2 recombinants with duplicated and deficient chromosome segments, including the regions distal to the inversion, may be produced. We report on 2 relatives in a family with opposite terminal chromosomal rearrangements of chromosome 10, i.e. rec(10)dup(10p)inv(10) and rec(10)dup(10q)inv(10), due to familial pericentric inversion inv(10)(p15.1q26.12). Based on array-CGH results, we characterized the exact genomic regions involved and compared the clinical features of both patients with previous reports on similar pericentric inversions and regional differences within 10p and 10q. The fact that both products of recombination are viable indicates a potentially high recurrence risk of unbalanced offspring. This report of unbalanced rearrangements in chromosome 10 in 2 generations confirms the importance of screening for terminal imbalances in patients with idiopathic intellectual disability by molecular cytogenetic techniques such as FISH, MLPA or microarrays. It also underlines the necessity for FISH to define structural characteristics of such cryptic intrachromosomal rearrangements and the underlying cytogenetic mechanisms. © 2014 S. Karger AG, Basel.

  15. Tetrasomy 15q11-q13 Diagnosed by FISH in a Patient with Autistic Disorder

    Directory of Open Access Journals (Sweden)

    Karim Ouldim

    2007-01-01

    Full Text Available We report the case of a Moroccan boy with mental retardation, hyperactivity, epilepsy, developmental problems and behavioural disorders. Cytogenetic analysis showed the presence of a supernumerary marker chromosome. Molecular cytogenetics allowed us to determine the marker as an inverted duplication of chromosome 15. It is the first case of a Moroccan patient with tetrasomy 15q in which fluorescence in situ hybridization (FISH enabled us to specify the diagnosis. Interestingly, this patient has an infantile autism with cytogenetic abnormalities on chromosomal region 15q11-q13 as reported in patients with Autistic Disorder.

  16. Mosaic tetrasomy 15q25{yields}qter in a newborn infant with multiple anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Van den Enden, A.; Roy, N.V.; Speleman, F. [Univ. Hospital, Gent (Belgium)

    1996-06-14

    We describe a premature boy with metopic craniosynostosis, facial anomalies, atrial-septal defect, hydronephrosis and flexion contractures of lower limbs, and mosaic tetrasomy 15q25{r_arrow}qter. The extra chromosome material was present in the form of an acentric marker. A number of clinical manifestations observed in this child were also found in 3 previously reported patients who were trisomic for the same part of chromosome 15 and in 2 patients who were tetrasomic for a larger segment of 15q. 17 refs., 4 figs., 1 tab.

  17. Proximal dup(10q): Case report and literature review

    Energy Technology Data Exchange (ETDEWEB)

    Barritt, J.A.; Teague, K.E.; Bodurtha, J.N. [Virginia Commonwealth Univ., Richmond, VA (United States)] [and others

    1994-09-01

    We report a case of a proximal dir dup(10q) in a female with multiple congenital anomalies. During infancy she was noted to gave growth retardation, microcephaly, microphthalmia, coloboma, a long, beaked nose, posteriorly rotated ears with simple helices, full bowed lips, widely-spaced nipples, broad first toes, hypermobile and proximally placed thumbs, a heart murmur, PDA, and coarctation of the aorta. Additional findings at age 13 included a full columella, short philtrum, thin limbs, bilateral blindness, and mental retardation, as well as continued growth retardation. Her medical history included precocious puberty at age 8 and a diagnosis of hyperactivity. Using FISH with multiple probes combined with GTG-banding, the aberrant chromosome was determined to be a dir dup(10)(q21{r_arrow}q22). Parental chromosomes were normal and the family history was unremarkable. The parental origin of the dir dup(10) is being assessed using DNA markers. Five similar cases of proximal dup(10q) have been reported previously. Consistent characteristics include low birth weight, developmental and psychomotor delay, growth retardation, and microcephaly. Also found in most cases were short prominent philtrum, bowed mouth, PDA, thin limbs, coloboma, micropthalmia, deep set eyes, and other ocular anomalies. Our case is unique in that she has a long, beaked nose, precocious puberty, and hyperactivity. Future studies such as this, using molecular cytogenetic techniques to better define the chromatin involved in proximal dup(10q), may lead to its recognition as a distinct clinical phenotype.

  18. Prenatal diagnosis of mosaic tetrasomy 12p/trisomy 12p by fluorescent in situ hybridization in amniotic fluid cells: A case report of Pallister-Killian syndrome

    NARCIS (Netherlands)

    F.J. Los; A.R.M. van Opstal (Diane); M.P. Schol (M.); J.L.J. Gaillard (J. L J); H. Brandenburg (Helen); A.M.W. van den Ouweland (Ans); P.A. In't Veld (Peter)

    1995-01-01

    textabstractA prenatally detected case of a rare mosaic tetrasomy 12p/trisomy 12p is reported, presenting as the well‐known accessory isochromosome 12p and a supernumerary single 12p marker in 17/24 and 6/24 clones of cultured amniotic fluid cells, respectively. The chromosomal nature of both marker

  19. The inv dup (15 or idic (15 syndrome (Tetrasomy 15q

    Directory of Open Access Journals (Sweden)

    Battaglia Agatino

    2008-11-01

    Full Text Available Abstract The inv dup(15 or idic(15 syndrome displays distinctive clinical findings represented by early central hypotonia, developmental delay and intellectual disability, epilepsy, and autistic behaviour. Incidence at birth is estimated at 1 in 30,000 with a sex ratio of almost 1:1. Developmental delay and intellectual disability affect all individuals with inv dup(15 and are usually moderate to profound. Expressive language is absent or very poor and often echolalic. Comprehension is very limited and contextual. Intention to communicate is absent or very limited. The distinct behavioral disorder shown by children and adolescents has been widely described as autistic or autistic-like. Epilepsy with a wide variety of seizure types can occur in these individuals, with onset between 6 months and 9 years. Various EEG abnormalities have been described. Muscle hypotonia is observed in almost all individuals, associated, in most of them, with joint hyperextensibility and drooling. Facial dysmorphic features are absent or subtle, and major malformations are rare. Feeding difficulties are reported in the newborn period. Chromosome region 15q11q13, known for its instability, is highly susceptible to clinically relevant genomic rearrangements, such as supernumerary marker chromosomes formed by the inverted duplication of proximal chromosome 15. Inv dup(15 results in tetrasomy 15p and partial tetrasomy 15q. The large rearrangements, containing the Prader-Willi/Angelman syndrome critical region (PWS/ASCR, are responsible for the inv dup(15 or idic(15 syndrome. Diagnosis is achieved by standard cytogenetics and FISH analysis, using probes both from proximal chromosome 15 and from the PWS/ASCR. Microsatellite analysis on parental DNA or methylation analysis on the proband DNA, are also needed to detect the parent-of-origin of the inv dup(15 chromosome. Array CGH has been shown to provide a powerful approach for identifying and detecting the extent of the

  20. Complex distal 10q rearrangement in a girl with mild intellectual disability

    DEFF Research Database (Denmark)

    Sarri, Catherine; Douzgou, Sofia; Gyftodimou, Yolanda

    2011-01-01

    several reports of satellited non-acrocentric chromosomes, which presumably result from a translocation with an acrocentric chromosome. This is, to our knowledge, the third report of a 10qs chromosome. The phenotype observed in the proband prompted a search for a structural rearrangement of chromosome 10q......We report on an intellectually disabled girl with a de novo satellited chromosome 10 (10qs) and performed a review of the literature of the non-acrocentric satellited chromosomes (NASC). Satellites and stalks normally occur on the short arms of acrocentric chromosomes; however, the literature cites....... By microsatellite analysis we observed a 4 Mb deletion on the long arm of chromosome 10, approximately 145 kb from the telomere. FISH and array CGH analyses revealed a complex rearrangement involving in range from the centromere to the telomere: A 9.64 Mb 10q26.11-q26.2 duplication, a 1.3 Mb region with no copy...

  1. Tetrasomy 15q12 in a patient with Angelman-like syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Ringer, K. [Univ. of Missouri School of Medicine, Kansas City, MO (United States); Huang, B.; Christian, S. [National Center for Human Genome Research, Bethesda, MD (United States)] [and others

    1994-09-01

    Supernumerary psu dic(15;15) chromosomes make up approximately 40% of livebirths possessing marker chromosomes. Markers with various chromosomal contents as well as a spectrum of phenotypes have been described. A few individuals with Angelman syndrome (AS) who have paternal uniparental disomy (UPD) for chromosome 15 or a 15q12 deletion in addition to a supernumerary psu dic(15;15) have been reported. We studied a patient who had a clinical phenotype consistent with AS including ataxic gait, severe mental retardation, absent speech and inappropriate laughter. Cytogenetic and FISH analysis showed a 47,XX,+psu dic(15q12;15q12) karyotype in which the supernumerary chromosome was positive for DNA probes in the AS critical region. Additional molecular analyses confirmed the presence of four copies of the 15q11{r_arrow}13 segment and that the psu dic(15;15) was maternal in origin. Two distal chromosome 15 markers showed normal, biparental inheritance for the two normal 15 homologues. A patient similar to ours was outlined by Stupca et al., although results of DNA analyses and parental origin were not given. In both patients, tetrasomy 15q12 resulted in an AS phenotype. The significance of the ratio of maternally:paternally derived sequences, 3:1 in our case, is unknown at present.

  2. Autism spectrum disorder with microdeletion 10q26 by subtelomere FISH

    Directory of Open Access Journals (Sweden)

    Tonk VS

    2011-05-01

    Full Text Available Vijay S Tonk1,2, Golder N Wilson11Department of Pediatrics, Texas Tech University Health Sciences Center, Lubbock, TX, USA; 2Departments of Pathology, Obstetrics and Gynecology, Texas Tech University Health Sciences Center, Lubbock, TX, USAAbstract: An 11-year-old female with early feeding problems, mild motor delays, normal speech, subtle facial changes, social difficulties, anxiety and a diagnosis of Asperger disorder was found to have deletion of 10q26.3 by subtelomere fluorescent in situ hybridization (stF analysis. Our patient and others with 10q26 aneuploidy add this region to 11 other autism susceptibility loci qualified by converging genome linkage/association, high resolution chromosome, and mutation studies in our review. We summarize these loci and the current spectrum of terminal 10q deletion cases.Keywords: autism disorder, Asperger disorder, subtelomere FISH, microarray analysis, 10q26 deletion, gene changes in autism

  3. Tetrasomy 21 pter {yields} q22.1 and Down syndrome: Molecular definition of the region

    Energy Technology Data Exchange (ETDEWEB)

    Daumer-Haas, C.; Schuffenhauer, S.; Walther, J.U. [Universitaet Muenchen (Germany); Portsmann, T. [Humboldt Universitaet, Berlin (Germany); Korenberg, J.R.; Schipper, R.D. [Univ. of California, Los Angeles, CA (United States)

    1994-12-01

    Down syndrome is usually caused by complete trisomy 21. Rarely, it is due to partial trisomy of the segment 21q22. We report on a 33-month-old girl with tetrasomy 21 pter {yields} q22.1 resulting from an extra chromosome idic(21)(q22.1). She has craniofacial traits typical of Down syndrome, including brachycephaly, third fontanel, upward slanting palpebral fissures, round face, and protruding tongue. Speech development is quite delayed whereas motor development is only mildly retarded. The molecular content of the extra isodicentric chromosome was defined by molecular genetic investigations using 13 single copy probes unique to chromosome 21, and SOD1 expression studies. The child was found to have 4 copies of the region defined by D21S16 (21cen) through D21S93 on 21q22.1 and two copies of the remaining region defined by SOD1 {yields} D21S55 {yields} D21S123. In view of the recent assignment of Down syndrome facial characters to the 21q22 region, defined in part by D21S55, it is significant that this child shows a subset of Down syndrome facial manifestations, without duplication of this region. These results suggest that genes contributing to the facial and some of the hand manifestations of Down syndrome also exist in the chromosomal region proximal to D21S55 in band 21q22.1. 34 refs., 6 figs., 3 tabs.

  4. Cytogenetic characterization of cat eye syndrome marker chromosome.

    Science.gov (United States)

    Wenger, S L; Surti, U; Nwokoro, N A; Steele, M W

    1994-01-01

    Cat eye syndrome is associated with a partial tetrasomy 22q and can be inherited. The authors have evaluated the marker chromosome in a proband and his mother by cytogenetic banding techniques to verify the dicentric chromosomal rearrangement and by fluorescence in situ hybridization to confirm the involvement of 22. The mother also had an affected offspring with an unrelated aneuploidy, trisomy 21.

  5. Severe intellectual disability, West syndrome, Dandy-Walker malformation, and syndactyly in a patient with partial tetrasomy 17q25.3.

    Science.gov (United States)

    Hackmann, Karl; Stadler, Anja; Schallner, Jens; Franke, Kathlen; Gerlach, Eva-Maria; Schrock, Evelin; Rump, Andreas; Fauth, Christine; Tinschert, Sigrid; Oexle, Konrad

    2013-12-01

    We report on a de novo 0.5 Mb triplication (partial tetrasomy) of chromosome 17q25.3 in a 10-year-old girl with severe intellectual disability, infantile seizures (West syndrome), moderate hearing loss, Dandy-Walker malformation, microcephaly, craniofacial dysmorphism, striking cutaneous syndactyly (hands 3-4, feet 2-3), joint laxity, and short stature. The triplication resulted from the unusual combination of a terminal duplication at 17qter and a cryptic translocation of an extra copy of the same segment onto chromosome 10qter. The breakpoint at 17q25.3 was located within the FOXK2 gene. SNP chip analysis suggested that the rearrangement occurred during paternal meiosis involving both paternal chromosomes 17. © 2013 Wiley Periodicals, Inc.

  6. Ventricular noncompaction and absent thumbs in a newborn with tetrasomy 5q35.2-5q35.3: an association with Hunter-McAlpine syndrome?

    Science.gov (United States)

    Sellars, Elizabeth A; Zimmerman, Sarah L; Smolarek, Teresa; Hopkin, Robert J

    2011-06-01

    We report on an infant with tetrasomy of 5q35.2-5q35.3, an interstitial triplication on one chromosome and normal complement on the other. The patient has some features of Hunter-McAlpine syndrome including intrauterine growth retardation (IUGR), almond-shaped eyes, epicanthal folds, and downturned mouth with thin vermillion of the upper lip. In addition, left ventricular noncompaction and absent thumbs were identified, which have never been described in Hunter-McAlpine syndrome. This chromosome abnormality is distinct from those previously reported. Within this region of tetrasomy is MSX2, a highly conserved homeobox containing gene. Increased copies of MSX2 have been previously associated with craniosynostosis. Our patient's only skeletal defect is absent thumbs, also potentially related to increased dosage of MSX2 which is important for limb formation. In addition, MSX2 is expressed in the developing heart and overexpression of this gene may disrupt the co-regulation of other cardiac genes in this region, namely CSX1. Copyright © 2011 Wiley-Liss, Inc.

  7. Chromosome

    Science.gov (United States)

    Chromosomes are structures found in the center (nucleus) of cells that carry long pieces of DNA. DNA ... is the building block of the human body. Chromosomes also contain proteins that help DNA exist in ...

  8. Cat eye syndrome owing to tetrasomy 22pter leads to q11.

    Science.gov (United States)

    Wilson, G N; Baker, D L; Schau, J; Parker, J

    1984-01-01

    A case of tetrasomy 22pter leads to q11 with ocular hypertelorism, downward slanting palpebral fissures, total anomalous pulmonary venous return, and anal atresia is described. The phenotypic variability of the cat eye syndrome is emphasised along with the need for categorisation of these patients according to well characterised cytogenetic findings. Images PMID:6694188

  9. Cat eye syndrome owing to tetrasomy 22pter leads to q11.

    OpenAIRE

    Wilson, G N; Baker, D L; Schau, J; Parker, J

    1984-01-01

    A case of tetrasomy 22pter leads to q11 with ocular hypertelorism, downward slanting palpebral fissures, total anomalous pulmonary venous return, and anal atresia is described. The phenotypic variability of the cat eye syndrome is emphasised along with the need for categorisation of these patients according to well characterised cytogenetic findings.

  10. Chromosomes

    Science.gov (United States)

    ... a new cell, the centromere serves as an attachment site for the two halves of each replicated ... of each chromosome is inherited from the female parent and the other from the male parent. This ...

  11. Microduplication of 10q26.3 in a Chinese hypertriglyceridemia patient.

    Science.gov (United States)

    Li, Jing-Jing; Chen, Ya-Qin; Fan, Liang-Liang; Jin, Jie-Yuan; Guo, Shuai; Xiang, Rong

    2017-11-10

    Hypertriglyceridemia (HTG) plays an important role in the development and progression of atherosclerosis. It is inherited in an autosomal dominant pattern with a frequency of approximately 1:1,000,000 worldwide. Previous study has demonstrated that more than six genes underlie this disorder. In addition, copy number variants (CNVs) including disease-causing genes also play a crucial role in it. In this study, we have employed SNP-ARRAY chip technology to detect the pathogenic CNVs in a HTG patient who carried no meaningful mutations in HTG candidate genes. And we identified a de novo CNV interstitial 134.7 kb duplication of chromosome region 10q26.3 containing CYP2E1. And this CNV also has been confirmed by Real-time PCR. CYP2E1 is a member of cytochrome P450 superfamily of enzymes which play an important role in fatty acid metabolism. Our study is consistent with previous research and further claimes that CNVs containing CYP2E1 may be related to HTG and obesity. Our study not only further confirmes the hypothesis that the CYP2E1 is a plausible candidate gene for HTG, but also may contribute to the diagnosis and treatment of these genomic diseases. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Myeloid Sarcoma and Acute Myelomonocytic Leukemia in an Adolescent with Tetrasomy 8: Staging With {sup 18}F-FDG PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Makis, William [Brandon Regional Health Centre, Brandon (Canada); Rakheja, Rajan; Lavoie, Josee; Marc Hickeson [McGill Univ. Health Centre, Brandon (Canada)

    2012-06-15

    Tetrasomy 8 is a relatively rare chromosomal abnormality that has been reported in only 33 cases in hematologic disorders, It is known for its association with aggressive acute myeloid leukemia (AML) and myeloid sarcoma and is considered a very poor prognostic factor. Myeloid sarcoma is a rare hematologic malignancy characterized by tumor masses consisting of immature myeloid cells, presenting at an extramedullary site. We present a case of a 17-year-old boy referred for an {sup 18}F-FDG PET/CT for the evaluation of pleural masses and spinal bone lesions seen on CT, after presenting with a 4 month history of chest pain. The PET/CT revealed extensive FDG-avid extrame-dullary disease in the soft tissues of the chest, abdomen, and pelvis, which were biopsy-proven to be myeloid sarcoma, as well as extensive intramedullary disease biopsy proven to be AML. This is the first report of the use of {sup 18}F-FDG PET/CT to stage a subset of aggressive AML and myeloid sarcoma in a patient with an associated chromosomal abnormality (tatrasomy 8)

  13. Syntenic homology of human unique DNA sequences within chromossome regions 5q31, 10q22, 13q32-33 and 19q13.1 in the great apes

    Directory of Open Access Journals (Sweden)

    Vallente-Samonte Rhea U.

    2000-01-01

    Full Text Available Homologies between chromosome banding patterns and DNA sequences in the great apes and humans suggest an apparent common origin for these two lineages. The availability of DNA probes for specific regions of human chromosomes (5q31, 10q22, 13q32-33 and 19q13.1 led us to cross-hybridize these to chimpanzee (Pan troglodytes, PTR, gorilla (Gorilla gorilla, GGO and orangutan (Pongo pygmaeus, PPY chromosomes in a search for equivalent regions in the great apes. Positive hybridization signals to the chromosome 5q31-specific DNA probe were observed at HSA 5q31, PTR 4q31, GGO 4q31 and PPY 4q31, while fluorescent signals using the chromosome 10q22-specific DNA probe were noted at HSA 10q22, PTR 8q22, GGO 8q22 and PPY 7q22. The chromosome arms showing hybridization signals to the Quint-EssentialTM 13-specific DNA probe were identified as HSA 13q32-33, PTR 14q32-33, GGO 14q32-33 and PPY 14q32-33, while those presenting hybridization signals to the chromosome 19q13.1-specific DNA probe were identified as HSA 19q13.1, PTR 20q13, GGO 20q13 and PPY 20q13. All four probes presumably hybridized to homologous chromosomal locations in the apes, which suggests a homology of certain unique DNA sequences among hominoid species.

  14. Cognitive and medical features of chromosomal aneuploidy.

    Science.gov (United States)

    Hutaff-Lee, Christa; Cordeiro, Lisa; Tartaglia, Nicole

    2013-01-01

    This chapter describes the physical characteristics, medical complications, and cognitive and psychological profiles that are associated with chromosomal aneuploidy conditions, a group of conditions in which individuals are born with one or more additional chromosome. Overall, chromosomal aneuploidy conditions occur in approximately 1 in 250 children. Information regarding autosomal disorders including trisomy 21 (Down syndrome), trisomy 13 (Patau syndrome), and trisomy 18 (Edward syndrome) are presented. Sex chromosome aneuploidy conditions such as Klinefelter syndrome (47,XXY), XYY, trisomy X, and Turner syndrome (45,X), in addition to less frequently occurring tetrasomy and pentasomy conditions are also covered. Treatment recommendations and suggestions for future research directions are discussed. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. 5q- syndrome-like features as the first manifestation of myelodysplastic syndrome in a patient with an unbalanced whole-arm translocation der(5;19)(p10;q10).

    Science.gov (United States)

    Ureshino, Hiroshi; Kizuka, Haruna; Kusaba, Kana; Sano, Haruhiko; Nishioka, Atsujiro; Shindo, Takero; Kubota, Yasushi; Ando, Toshihiko; Kojima, Kensuke; Kimura, Shinya

    2017-05-01

    Derivative (5;19)(p10;q10) [der(5;19)(p10;q10)] is a rare chromosomal abnormality in myelodysplastic syndrome (MDS), and is genetically similar to deletion 5q [del(5q)]. However, MDS with der(5;19)(p10;q10) and 5q- syndrome are generally characterized as distinct subtypes. Here, we report a case of a patient with 5q- syndrome-like features as the first manifestation of MDS with der(5; 19)(p10;q10). A 59-year-old woman was admitted to our hospital for anemia without leukopenia and thrombocytopenia. She had received chemotherapy comprising carboplatin and docetaxel for endometrial cancer eight years before. Bone marrow aspirate (BM) revealed low blast counts with trilineage dysplastic cells, and fluorescent in situ hybridization revealed the loss of colony-stimulating factor 1 receptor (CSF1R) signals at 5q33-34. Although the initial manifestation was 5q- syndrome, G-banded metaphase analysis and spectral karyotyping analysis revealed der(5;19)(p10;q10). Consequently, a diagnosis of therapy-related MDS (t-MDS) was made. She failed to respond to azacitidine and lenalidomide therapy. Consequently, transfusion-dependent anemia and thrombocytopenia developed with increasing myeloblasts. Cytarabine, aclarubicin, and granulocyte colony-stimulating factor therapy also failed, and unfortunately the patient died. Thus, MDS with der(5;19)(p10;q10) may represent a platinum agent-related t-MDS that is highly resistant to chemotherapy.

  16. Autosomal recessive spastic paraplegia (SPG45) with mental retardation maps to 10q24.3-q25.1.

    Science.gov (United States)

    Dursun, Umut; Koroglu, Cigdem; Kocasoy Orhan, Elif; Ugur, Sibel Aylin; Tolun, Aslihan

    2009-10-01

    Hereditary spastic paraplegias (HSPs) are characterized by progressive spasticity in the lower limbs. They are clinically heterogeneous, and pure forms as well as complicated forms with other accompanying clinical findings are known. HSPs are also genetically heterogeneous. We performed clinical and genetic studies in a consanguineous family with five affected members. A genome scan using 405 microsatellite markers for eight members of the family identified candidate gene loci, and subsequent fine mapping in 16 members identified the gene locus responsible for the HSP. The clinical manifestations were very early onset spastic paraplegia (SPG) accompanied by mental retardation and ocular signs. The gene locus was identified as the interval 102.05-106.64 Mbp on chromosome 10. Gene MRPL43 was analyzed in the patients. No mutation but high levels of mRNA were detected. We have mapped a novel autosomal recessive complicated form of HSP (SPG45) to a 4.6-Mbp region at 10q24.3-q25.1 with multipoint logarithm of odds scores >4.5.

  17. Chromosomal Abnormalities Associated With Omphalocele

    Directory of Open Access Journals (Sweden)

    Chih-Ping Chen

    2007-03-01

    Full Text Available Fetuses with omphalocele have an increased risk for chromosomal abnormalities. The risk varies with maternal age, gestational age at diagnosis, association with umbilical cord cysts, complexity of associated anomalies, and the contents of omphalocele. There is considerable evidence that genetics contributes to the etiology of omphalocele. This article provides an overview of chromosomal abnormalities associated with omphalocele and a comprehensive review of associated full aneuploidy such as trisomy 18, trisomy 13, triploidy, trisomy 21, 45,X, 47,XXY, and 47,XXX, partial aneuploidy such as dup(3q, dup(11p, inv(11, dup(1q, del(1q, dup(4q, dup(5p, dup(6q, del(9p, dup(15q, dup(17q, Pallister-Killian syndrome with mosaic tetrasomy 12p and Miller-Dieker lissencephaly syndrome with deletion of 17p13.3, and uniparental disomy (UPD such as UPD 11 and UPD 14. Omphalocele is a prominent marker for chromosomal abnormalities. Perinatal identification of omphalocele should alert chromosomal abnormalities and familial unbalanced translocations, and prompt thorough cytogenetic investigations and genetic counseling.

  18. Identification of a Novel Gene on 10q22.1 Causing Autosomal Dominant Retinitis Pigmentosa (adRP).

    Science.gov (United States)

    Daiger, Stephen P; Sullivan, Lori S; Bowne, Sara J; Koboldt, Daniel C; Blanton, Susan H; Wheaton, Dianna K; Avery, Cheryl E; Cadena, Elizabeth D; Koenekoop, Robert K; Fulton, Robert S; Wilson, Richard K; Weinstock, George M; Lewis, Richard A; Birch, David G

    2016-01-01

    Whole-genome linkage mapping identified a region on chromosome 10q21.3-q22.1 with a maximum LOD score of 3.0 at 0 % recombination in a six-generation family with autosomal dominant retinitis pigmentosa (adRP). All known adRP genes and X-linked RP genes were excluded in the family by a combination of methods. Whole-exome next-generation sequencing revealed a missense mutation in hexokinase 1, HK1 c.2539G > A, p.Glu847Lys, tracking with disease in all affected family members. One severely-affected male is homozygous for this region by linkage analysis and has two copies of the mutation. No other potential mutations were detected in the linkage region nor were any candidates identified elsewhere in the genome. Subsequent testing detected the same mutation in four additional, unrelated adRP families, for a total of five mutations in 404 probands tested (1.2 %). Of the five families, three are from the Acadian population in Louisiana, one is French Canadian and one is Sicilian. Haplotype analysis of the affected chromosome in each family and the homozygous individual revealed a rare, shared haplotype of 450 kb, suggesting an ancient founder mutation. HK1 is a widely-expressed gene, with multiple, abundant retinal transcripts, coding for hexokinase 1. Hexokinase catalyzes phosphorylation of glucose to glusose-6-phospate, the first step in glycolysis. The Glu847Lys mutation is in a highly-conserved site, outside of the active site or known functional sites.

  19. Chimerism and multiple numerical chromosome imbalances in a spontaneously aborted fetus.

    Science.gov (United States)

    Vorsanova, S G; Iourov, I Y; Demidova, I A; Kirillova, E A; Soloviev, I V; Yurov, Y B

    2006-01-01

    We report on a case of chimerism and multiple abnormalities of chromosomes 21, Xand Yin spontaneous abortion specimen. To the best our knowledge the present case is the first documented chimera in a spontaneously aborted fetus. The application of interphase fluorescence in situ hybridization (FISH) using chromosome enumeration and site-specific DNA probes showed trisomy X in 92 nuclei (23 %), tetrasomy X in 100 nuclei (25 %), pentasomy of chromosome X in 40 nuclei (10 %), XXY in 36 nuclei (9 %), XXXXXXYY in 12 nuclei (3 %), XXXXXYYYYY in 8 nuclei (2 %), trisomy 21 and female chromosome complement in 40 nuclei (10 %), normal female chromosome complement in 72 nuclei (18 %) out of 400 nuclei scored. Our experience indicates that the frequency of chimerism coupled with multiple chromosome abnormalities should be no less than 1 : 400 among spontaneous abortions. The difficulties of chimerism identification in fetal tissues are discussed.

  20. Localization of the nucleotide excision repair gene ERCC-6 to human chromosome 10q11-q21.

    NARCIS (Netherlands)

    C. Troelstra (Christine); R.M. Landsvater; J. Wiegant; M. van der Ploeg; G. Viel; C.H.C.M. Buys; J.H.J. Hoeijmakers (Jan)

    1992-01-01

    textabstractWe have cloned the human DNA excision repair gene ERCC6 by virtue of its ability to correct the uv sensitivity of Chinese hamster overy cell mutant UV61. This mutant is a member of complementation group 6 of the nucleotide excision repair-deficient rodent mutants. By means of in situ

  1. Toward cloning of a novel ataxia gene: Refined assignment and physical map of the IOSCA locus (SCA8) on 10q24

    Energy Technology Data Exchange (ETDEWEB)

    Nikali, K.; Isosomppi, J.; Suomalainen, A. [Univ. of Helsinki (Finland)] [and others

    1997-01-15

    Infantile onset spinocerebellar ataxia (IOSCA) is a progressive neurological disorder of unknown etiology. It is inherited as an autosomal recessive trait and has so far been reported in just 19 Finnish patients in 13 separate families. We have previously assigned the IOSCA locus (HGMW-approved symbol SCA8) to chromosome 10q, where no previously identified ataxia loci are located. Haplotype analysis combined with genealogical data provided evidence that all the IOSCA cases in Finland originate from a single 30- to 40-generation-old founder mutation. By analyzing extended disease haplotypes observed today, the IOSCA locus can now be restricted to a region between two adjacent microsatellites, D10S192 and D10S1265, with no genetic intermarker distance. We have constructed a detailed physical map of this 270-kb IOSCA region and cytogenetically localized it to 10q24. We have also assigned two previously known genes, PAX2 and CYP17, more precisely into this region, but the sequence analysis of coding regions of these two genes has not revealed mutations in an IOSCA patient. The obtained long-range clones will form the basis for the isolation of a novel ataxia gene. 42 refs., 3 figs.

  2. Expansion of the clinical phenotype of the distal 10q26.3 deletion syndrome to include ataxia and hyperemia of the hands and feet.

    Science.gov (United States)

    Lacaria, Melanie; Srour, Myriam; Michaud, Jacques L; Doja, Asif; Miller, Elka; Schwartzentruber, Jeremy; Goldsmith, Claire; Majewski, Jacek; Boycott, Kym M

    2017-06-01

    Distal deletion of the long arm of chromosome 10 is associated with a dysmorphic craniofacial appearance, microcephaly, behavioral issues, developmental delay, intellectual disability, and ocular, urogenital, and limb abnormalities. Herein, we present clinical, molecular, and cytogenetic investigations of four patients, including two siblings, with nearly identical terminal deletions of 10q26.3, all of whom have an atypical presentation of this syndrome. Their prominent features include ataxia, mild-to-moderate intellectual disability, and hyperemia of the hands and feet, and they do not display many of the other features commonly associated with deletions of this region. These results point to a novel gene locus associated with ataxia and highlight the variability of the clinical presentation of patients with deletions of this region. © 2017 Wiley Periodicals, Inc.

  3. A first case of primary amenorrhea with i(X)(qter---q10::---qter), rob(13;14)(q10;q10), inv(9)(p13q33) karyotype.

    Science.gov (United States)

    Korgaonkar, Seema; Ghosh, Kanjaksha; Vundinti, Babu Rao

    2011-01-01

    Primary amenorrhea (PA) refers to the absence of menarche by the age of 16-18 years although secondary sexual characters are developed. PA occurs in 1-3% of women in the reproductive age group. Various factors such as anatomical, genetic and hormonal factors reported to influence PA. We report triple chromosomal abnormalities of rob(13;14)(q10;q10),inv(9)(p13q33), i(Xq)(qter---q10::---qter) in a case of PA and short stature. Though proband has multiple chromosome aberrations, genotypic effect of only i(Xq) is evident as proband has PA and short stature. The rob(13;14) and inv(9), which are paternally derived may have role in later reproductive age. Therefore, chromosomal analysis is essential in such cases for the accurate diagnosis and management of the disease.

  4. Polymorphisms in a Putative Enhancer at the 10q21.2 Breast Cancer Risk Locus Regulate NRBF2 Expression

    Science.gov (United States)

    Darabi, Hatef; McCue, Karen; Beesley, Jonathan; Michailidou, Kyriaki; Nord, Silje; Kar, Siddhartha; Humphreys, Keith; Thompson, Deborah; Ghoussaini, Maya; Bolla, Manjeet K.; Dennis, Joe; Wang, Qin; Canisius, Sander; Scott, Christopher G.; Apicella, Carmel; Hopper, John L.; Southey, Melissa C.; Stone, Jennifer; Broeks, Annegien; Schmidt, Marjanka K.; Scott, Rodney J.; Lophatananon, Artitaya; Muir, Kenneth; Beckmann, Matthias W.; Ekici, Arif B.; Fasching, Peter A.; Heusinger, Katharina; dos-Santos-Silva, Isabel; Peto, Julian; Tomlinson, Ian; Sawyer, Elinor J.; Burwinkel, Barbara; Marme, Frederik; Guénel, Pascal; Truong, Thérèse; Bojesen, Stig E.; Flyger, Henrik; Benitez, Javier; González-Neira, Anna; Anton-Culver, Hoda; Neuhausen, Susan L.; Arndt, Volker; Brenner, Hermann; Engel, Christoph; Meindl, Alfons; Schmutzler, Rita K.; Arnold, Norbert; Brauch, Hiltrud; Hamann, Ute; Chang-Claude, Jenny; Khan, Sofia; Nevanlinna, Heli; Ito, Hidemi; Matsuo, Keitaro; Bogdanova, Natalia V.; Dörk, Thilo; Lindblom, Annika; Margolin, Sara; Kosma, Veli-Matti; Mannermaa, Arto; Tseng, Chiu-chen; Wu, Anna H.; Floris, Giuseppe; Lambrechts, Diether; Rudolph, Anja; Peterlongo, Paolo; Radice, Paolo; Couch, Fergus J.; Vachon, Celine; Giles, Graham G.; McLean, Catriona; Milne, Roger L.; Dugué, Pierre-Antoine; Haiman, Christopher A.; Maskarinec, Gertraud; Woolcott, Christy; Henderson, Brian E.; Goldberg, Mark S.; Simard, Jacques; Teo, Soo H.; Mariapun, Shivaani; Helland, Åslaug; Haakensen, Vilde; Zheng, Wei; Beeghly-Fadiel, Alicia; Tamimi, Rulla; Jukkola-Vuorinen, Arja; Winqvist, Robert; Andrulis, Irene L.; Knight, Julia A.; Devilee, Peter; Tollenaar, Robert A.E.M.; Figueroa, Jonine; García-Closas, Montserrat; Czene, Kamila; Hooning, Maartje J.; Tilanus-Linthorst, Madeleine; Li, Jingmei; Gao, Yu-Tang; Shu, Xiao-Ou; Cox, Angela; Cross, Simon S.; Luben, Robert; Khaw, Kay-Tee; Choi, Ji-Yeob; Kang, Daehee; Hartman, Mikael; Lim, Wei Yen; Kabisch, Maria; Torres, Diana; Jakubowska, Anna; Lubinski, Jan; McKay, James; Sangrajrang, Suleeporn; Toland, Amanda E.; Yannoukakos, Drakoulis; Shen, Chen-Yang; Yu, Jyh-Cherng; Ziogas, Argyrios; Schoemaker, Minouk J.; Swerdlow, Anthony; Borresen-Dale, Anne-Lise; Kristensen, Vessela; French, Juliet D.; Edwards, Stacey L.; Dunning, Alison M.; Easton, Douglas F.; Hall, Per; Chenevix-Trench, Georgia

    2015-01-01

    Genome-wide association studies have identified SNPs near ZNF365 at 10q21.2 that are associated with both breast cancer risk and mammographic density. To identify the most likely causal SNPs, we fine mapped the association signal by genotyping 428 SNPs across the region in 89,050 European and 12,893 Asian case and control subjects from the Breast Cancer Association Consortium. We identified four independent sets of correlated, highly trait-associated variants (iCHAVs), three of which were located within ZNF365. The most strongly risk-associated SNP, rs10995201 in iCHAV1, showed clear evidence of association with both estrogen receptor (ER)-positive (OR = 0.85 [0.82–0.88]) and ER-negative (OR = 0.87 [0.82–0.91]) disease, and was also the SNP most strongly associated with percent mammographic density. iCHAV2 (lead SNP, chr10: 64,258,684:D) and iCHAV3 (lead SNP, rs7922449) were also associated with ER-positive (OR = 0.93 [0.91–0.95] and OR = 1.06 [1.03–1.09]) and ER-negative (OR = 0.95 [0.91–0.98] and OR = 1.08 [1.04–1.13]) disease. There was weaker evidence for iCHAV4, located 5′ of ADO, associated only with ER-positive breast cancer (OR = 0.93 [0.90–0.96]). We found 12, 17, 18, and 2 candidate causal SNPs for breast cancer in iCHAVs 1–4, respectively. Chromosome conformation capture analysis showed that iCHAV2 interacts with the ZNF365 and NRBF2 (more than 600 kb away) promoters in normal and cancerous breast epithelial cells. Luciferase assays did not identify SNPs that affect transactivation of ZNF365, but identified a protective haplotype in iCHAV2, associated with silencing of the NRBF2 promoter, implicating this gene in the etiology of breast cancer. PMID:26073781

  5. A Non-Reciprocal Autosomal Translocation 64,XX, t(4;10)(q21;p15) in an Arabian Mare with Repeated Early Embryonic Loss.

    Science.gov (United States)

    Ghosh, S; Das, P J; Avila, F; Thwaits, B K; Chowdhary, B P; Raudsepp, T

    2016-02-01

    Balanced autosomal translocations are a known cause for repeated early embryonic loss (REEL) in horses. In most cases, carriers of such translocations are phenotypically normal, but the chromosomal aberration negatively affects gametogenesis giving rise to both genetically balanced and unbalanced gametes. The latter, if involved in fertilization, result in REEL, whereas gametes with the balanced form of translocation will pass the defect into next generation. Therefore, in order to reduce the incidence of REEL, identification of translocation carriers is critical. Here, we report about a phenotypically normal 3-year-old Arabian mare that had repeated resorption of conceptuses prior to day 45 of gestation and was diagnosed with REEL. Conventional and molecular cytogenetic analyses revealed that the mare had normal chromosome number 64,XX but carried a non-mosaic and non-reciprocal autosomal translocation t(4;10)(q21;p15). This is a novel translocation described in horses with REEL and the first such report in Arabians. Previous cases of REEL due to autosomal translocations have exclusively involved Thoroughbreds. The findings underscore the importance of routine cytogenetic screening of breeding animals. © 2015 Blackwell Verlag GmbH.

  6. Interaction Between a Chromosome 10 RET Enhancer and Chromosome 21 in the Down Syndrome-Hirschsprung Disease Association

    NARCIS (Netherlands)

    Arnold, Stacey; Pelet, Anna; Amiel, Jeanne; Borrego, Salud; Hofstra, Robert; Tam, Paul; Ceccherini, Isabella; Lyonnet, Stanislas; Sherman, Stephanie; Chakravarti, Aravinda

    Individuals with Down syndrome display a 40-fold greater risk of Hirschsprung disease (HSCR) than the general population of newborns implicating chromosome 21 in HSCR etiology. Here we demonstrate that the RET enhancer polymorphism RET + 9.7 (rs2435357:C > T) at chromosome 10q11.2 is associated with

  7. Duplication and loss of chromosome 21 in two children with Down Syndrome and acute leukemia

    Energy Technology Data Exchange (ETDEWEB)

    Rogan, P.K.; Close, P.; Seip, J.R. [Pennsylvania State Univ. College of Medicine, Hershey, PA (United States)] [and others

    1994-09-01

    Acute leukemia in patients with Trisomy 21 (Down Syndrome; DS) may often result in additional karyotypic changes in the number or structure of chromosome 21. We present two DS patients whose immunoblast karyotypes were associated with changes in chromosome 21 ploidy. Patient L.E. developed acute lymphocytic leukemia concomitant with the loss of a single copy of chromosome 21. Trisomy 21 in this individual was due to maternal meiosis I nondisjunction. A recombination event resulted in reduction of maternal alleles to homozygosity distal to D21S167. Loss of the paternal chromosomes in the leukemia clone produced uniparental maternal disomy with isodisomy over a 25cM interval. This could, in theory, permit the unopposed expression of one or more homozygous recessive maternal tumor-associated genes, thus providing an explanation for leukemogenesis in this patient. Patient E.H. was diagnosed with acute monoblastic leukemia and consistently displayed tetrasomy 21 in the blast cell population. The DS karyotype probably arose from a mitotic error in which the paternal chromosome was duplicated. DNA polymorphism analysis indicated that the additional chromosome in the leukemia clone was of maternal origin. The presence of equal numbers of maternal and paternal chromosomes in the tetraploid blast clone would not appear to be consistent with the expression of a mutant tumor suppressor gene in this patient. Although tetrasomy 21 could be a non-specific karyotypic abnormality unrelated to leukemogenesis, it is possible that monoblastic leukemia may be a consequence of increased expression of one or more genes on this chromosome.

  8. Molecular and clinical analyses with neuropsychological assessment of a case of del(10)(q26.2qter) without intellectual disability: Genomic and transcriptomic combined approach and review of the literature.

    Science.gov (United States)

    Laudier, Béatrice; Epiais, Tiphanie; Pâris, Arnaud; Menuet, Arnaud; Briault, Sylvain; Ozsancak, Canan; Perche, Olivier

    2016-07-01

    Terminal deletion of the long arm of the chromosome 10 is a rare but well known abnormality, with a large phenotypic variability. Very few data are available about subtelomeric deletion 10q26 patients without intellectual disability. Herein, we report the case of a young adult with a classical 10q26.2qter deletion. She exhibited mainly short stature at birth and in childhood/adulthood without intellectual disability or behavioral problems. After clinical and neuropsychological assessments, we performed genomic array and transcriptomic analysis and compared our results to the data available in the literature. The patient presents a 6.525 Mb heterozygous 10q26.2qter deletion, encompassed 48 genes. Among those genes, DOCK1, C10orf90, and CALY previously described as potential candidate genes for intellectual disability, were partially or completed deleted. Interestingly, they were not deregulated as demonstrated by transcriptomic analysis. This allowed us to suggest that the mechanism involved in the deletion 10qter phenotype is much more complex that only the haploinsufficiency of DOCK1 or other genes encompassed in the deletion. Genomic and transcriptomic combined approach has to be considered to understand this pathogenesis. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  9. Expression analyses of the genes harbored by the type 2 diabetes and pediatric BMI associated locus on 10q23

    Directory of Open Access Journals (Sweden)

    Zhao Jianhua

    2012-09-01

    Full Text Available Abstract Background There is evidence that one of the key type 2 diabetes (T2D loci identified by GWAS exerts its influence early on in life through its impact on pediatric BMI. This locus on 10q23 harbors three genes, encoding hematopoietically expressed homeobox (HHEX, insulin-degrading enzyme (IDE and kinesin family member 11 (KIF11, respectively. Methods We analyzed the impact of adipogeneis on the mRNA and protein expression levels of these genes in the human adipocyte Simpson-Golabi-Behmel syndrome (SGBS cell line in order to investigate which could be the culprit gene(s in this region of linkage disequilibrium. Results Following activation of differentiation with a PPARγ ligand, we observed ~20% decrease in IDE, ~40% decrease in HHEX and in excess of 80% decrease in KIF11 mRNA levels when comparing the adipocyte and pre-adipocyte states. We also observed decreases in KIF11 and IDE protein levels, but conversely we observed a dramatic increase in HHEX protein levels. Subsequent time course experiments revealed some marked changes in expression as early as three hours after activation of differentiation. Conclusion Our data suggest that the expression of all three genes at this locus are impacted during SGBS adipogenesis and provides insights in to the possible mechanisms of how the genes at this 10q23 locus could influence both adipocyte differentiation and susceptibility to T2D through insulin resistance.

  10. Chromosome Abnormalities

    Science.gov (United States)

    ... XX), and males have an X and a Y chromosome (XY). The mother and father each contribute one ... chromosome has attached to another at the centromere. Inversions: A portion of the chromosome has broken off, turned upside down, and reattached. ...

  11. FISH diagnosis of partial trisomy 13 and tetrasomy 13 in a patient with severe trigonocephaly (C) phenotype

    Energy Technology Data Exchange (ETDEWEB)

    Chu, T.W.; Teebi, A.S.; Gibson, L.; Breg, W.R.; Yang-Feng, T.L.

    1994-08-01

    An infant girl with manifestations resembling Opitz trigonocephaly (C) syndrome who died at age 6 days was found to have a complex chromosome abnormality with t(13;18)(q22;q23) and a recombinant chromosome 13 involving duplicated segments of 13q. Precise characterization was possible with the application of fluorescence in situ hybridization (FISH) using chromosome specific probes. The patient`s phenotype is compared to that of other syndromes involving trigonocephaly. 20 refs., 3 figs., 3 tabs.

  12. Rapid aneuploidy diagnosis of partial trisomy 7q (7q34→qter and partial monosomy 10q (10q26.12→qter by array comparative genomic hybridization using uncultured amniocytes

    Directory of Open Access Journals (Sweden)

    Chih-Ping Chen

    2012-03-01

    Conclusion: aCGH is a useful tool for RAD of subtle chromosomal rearrangements in pregnancy, especially under the circumstance of a previous abnormal child with an unbalanced translocation derived from a parental subtle reciprocal translocation.

  13. Development profile in a patient with monosomy 10q and Dup(17p) associated with a peripheral neuropathy

    Energy Technology Data Exchange (ETDEWEB)

    Pellegrino, J.E.; Spinner, N.B.; Zackai, E.H. [Childrens Hospital of Philadelphia, PA (United States)] [and others

    1996-02-02

    We report on a patient with dup(17p) and monosomy (10q) resulting from a familial translocation. Manifestations typical of both syndromes were present. The overall development of this patient was better by comparison with similar reported cases of either anomaly. Our evaluation detected severe gross motor delay and signs of a demyelinating peripheral neuropathy. This patient is trisomic for the region of 17p which includes the peripheral myelin protein-22 (PMP-22) gene, known to be duplicated in Charcot-Marie-Tooth neuropathy type 1A (CMT1A). Our analysis in this patient suggests that trisomy for the PMP-22 gene led to the demyelinating neuropathy and contributed to his severe motor development delay. 33 refs., 3 figs., 1 tab.

  14. Marker chromosomes.

    Science.gov (United States)

    Rao, Kiran Prabhaker; Belogolovkin, Victoria

    2013-04-01

    Marker chromosomes are a morphologically heterogeneous group of structurally abnormal chromosomes that pose a significant challenge in prenatal diagnosis. Phenotypes associated with marker chromosomes are highly variable and range from normal to severely abnormal. Clinical outcomes are very difficult to predict when marker chromosomes are detected prenatally. In this review, we outline the classification, etiology, cytogenetic characterization, and clinical consequences of marker chromosomes, as well as practical approaches to prenatal diagnosis and genetic counseling.

  15. Clinical Expression of an Inherited Unbalanced Translocation in Chromosome 6

    Directory of Open Access Journals (Sweden)

    Bani Bandana Ganguly

    2011-01-01

    Full Text Available Unbalanced chromosomal rearrangements are not common; however, they have a significant clinical expression. The parental balanced translocation produces unbalanced chromosome, which is transmitted to next generation through fertilization of gametes carrying the derivative chromosome. The carriers of balanced rearrangements mostly do not have recognizable phenotypic expression. We report a family comprising of healthy and non-consanguineous young parents and their preemie newborn severely affected with congenital anomalies and systemic disorders. Conventional Gbanding analysis of somatic chromosomes identified a balanced translocation, t(6;10(p23;q24, in mother and an unbalanced rearrangement, der(6t(6:10(p23;q24mat, in the child. The child has inherited a derivative chromosome 6 with partial deletion of 6(p23-pter and partial trisomy 10(q24-qter, which has resulted in fusion of genes of two different chromosomes. The prominent phenotypic features of del(6p, including high forehead, flat nasal bridge, agenesis of left ear, atrial septal defect (ASD, craniosynostosis, and growth retardation, are overlapping with specific Axenfeld-Reiger-, Larsen-, and Ritscher-Sinzel/3-C syndromes, however, lacking in ocular anomalies, skeletal laxity, or cerebellar malformation. Therefore, this paper rules out the isolated effect of del(6p23 or trisomy 10(q24 on distinct previously reported syndromes and proposes the combined effect of unbalanced chromosomal alteration.

  16. Fine mapping of a de novo interstitial 10q22-q23 duplication in a patient with congenital heart disease and microcephaly

    DEFF Research Database (Denmark)

    Erdogan, F; Belloso, J M; Gabau, E

    2008-01-01

    deletions or duplications elsewhere in the genome. The main clinical features of the patient are microcephaly and congenital heart disease, which are likely to be caused by dosage effect of one or several genes in the duplicated region. Similar phenotypes have been found in other patients with 10q11-q22...

  17. 31 CFR 30.10 - Q-10: What actions are necessary for a TARP recipient to comply with section 111(b)(3)(D) of EESA...

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Q-10: What actions are necessary for....10 Section 30.10 Money and Finance: Treasury Office of the Secretary of the Treasury TARP STANDARDS FOR COMPENSATION AND CORPORATE GOVERNANCE § 30.10 Q-10: What actions are necessary for a TARP...

  18. Polymorphisms in a Putative Enhancer at the 10q21.2 Breast Cancer Risk Locus Regulate NRBF2 Expression

    DEFF Research Database (Denmark)

    Darabi, Hatef; McCue, Karen; Beesley, Jonathan

    2015-01-01

    Genome-wide association studies have identified SNPs near ZNF365 at 10q21.2 that are associated with both breast cancer risk and mammographic density. To identify the most likely causal SNPs, we fine mapped the association signal by genotyping 428 SNPs across the region in 89,050 European and 12,...

  19. Interphase chromosomes

    Indian Academy of Sciences (India)

    First page Back Continue Last page Graphics. Interphase chromosomes. Genomes within interphase nuclei occupy discrete, three-dimensional regions known as 'chromosome territories' (Bridger and Bickmore, 1998, Cremer and Cremer, 2001, Parada and Misteli, 2002). The non-randomness of CT organization within an ...

  20. Modeling Chromosomes

    Science.gov (United States)

    Robertson, Carol

    2016-01-01

    Learning about chromosomes is standard fare in biology classrooms today. However, students may find it difficult to understand the relationships among the "genome", "chromosomes", "genes", a "gene locus", and "alleles". In the simple activity described in this article, which follows the 5E approach…

  1. Persistent Mosaicism for 12p Duplication/Triplication Chromosome Structural Abnormality in Peripheral Blood

    Directory of Open Access Journals (Sweden)

    Amy L. Shackelford

    2013-01-01

    Full Text Available We present a rare case of mosaicism for a structural abnormality of chromosome 12 in a patient with phenotypic features of Pallister-Killian syndrome. A six-month-old child with dysmorphic features, exotropia, hypotonia, and developmental delay was mosaic for both a normal karyotype and a cell line with 12p duplication/triplication in 25 percent of metaphase cells. Utilization of fluorescence in situ hybridization (FISH identified three copies of probes from the end of the short arm of chromosome 12 (TEL(12p13 locus and the subtelomere (12p terminal on the structurally abnormal chromosome 12. Genome-wide SNP array analysis revealed that the regions of duplication and triplication were of maternal origin. The abnormal cell line in our patient was present at 25 percent at six months and 19 months of age in both metaphase and interphase cells from peripheral blood, where typically the isochromosome 12p is absent in the newborn. This may suggest that the gene(s resulting in a growth disadvantage of abnormal cells in peripheral blood of patients with tetrasomy 12p may not have the same influence when present in only three copies.

  2. Müllerian Agenesis in Cat Eye Syndrome and 22q11 Chromosome Abnormalities: A Case Report and Literature Review.

    Science.gov (United States)

    AlSubaihin, Abdulmajeed; VanderMeulen, John; Harris, Kate; Duck, John; McCready, Elizabeth

    2017-09-14

    Although Müllerian agenesis is the second most common cause of primary amenorrhea the underlying etiology in most cases is unknown. Müllerian agenesis has been reported as a rare finding associated with chromosomal aberrations of the 22q11 chromosomal region including at least 1 individual with cat eye syndrome (CES) and 10 individuals with deletions or duplications of the 22q11.2 region. However, a potential link between 22q11 abnormalities and uterine malformations has been difficult to adequately ascertain because of the limited case reports in the literature. We report a second case of Müllerian agenesis in a girl with CES. A 16-year-old girl presented with bilateral colobomata, primary amenorrhea, and absence of the uterus and upper vagina on pelvic magnetic resonance imaging. Microarray analysis showed tetrasomy of the pericentromeric region of chromosome 22 diagnostic of CES. Müllerian aplasia/hypoplasia might represent a rare feature in CES and should be considered in the investigation of young girls with this syndrome. An increasing number of cases with 22q11 chromosome abnormalities and Müllerian agenesis further highlights the possibility of a gene within the 22q11 region that might mediate normal Müllerian development in girls. Copyright © 2017 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

  3. A report of paracentric inversion of chromosome 8 in Moebius syndrome.

    Science.gov (United States)

    Kersey, James P; Vivian, Anthony J; Reid, Evan

    2006-03-01

    An eight-year-old girl with bilateral facial paresis and restricted eye movements was diagnosed with Moebius syndrome. A chromosomal analysis showed a paracentric inversion on the long arm of chromosome 8 (46, XX, inv(8) (q21.3q24.13)). Candidate genes have been found on chromosomes 3q21, 10q21, and 13q12. We discuss the genes which are known to have associated ocular movement dysfunction in the 8q21-24 region. We hope this case will add to the current body of knowledge regarding Moebius syndrome and its genetics.

  4. Potential Signals of Natural Selection in the Top Risk Loci for Coronary Artery Disease: 9p21 and 10q11.

    Science.gov (United States)

    Zanetti, Daniela; Carreras-Torres, Robert; Esteban, Esther; Via, Marc; Moral, Pedro

    2015-01-01

    Coronary artery disease (CAD) is a complex disease and the leading cause of death in the world. Populations of different ancestry do not always share the same risk markers. Natural selective processes may be the cause of some of the population differences detected for specific risk mutations. In this study, 384 single nucleotide polymorphisms (SNPs) located in four genomic regions associated with CAD (1p13, 1q41, 9p21 and 10q11) are analysed in a set of 19 populations from Europe, Middle East and North Africa and also in Asian and African samples from the 1000 Genomes Project. The aim of this survey is to explore for the first time whether the genetic variability in these genomic regions is better explained by demography or by natural selection. The results indicate significant differences in the structure of genetic variation and in the LD patterns among populations that probably explain the population disparities found in markers of susceptibility to CAD. The results are consistent with potential signature of positive selection in the 9p21 region and of balancing selection in the 9p21 and 10q11. Specifically, in Europe three CAD risk markers in the 9p21 region (rs9632884, rs1537371 and rs1333042) show consistent signals of positive selection. The results of this study are consistent with a potential selective role of CAD in the configuration of genetic diversity in current human populations.

  5. Synthetic chromosomes.

    Science.gov (United States)

    Schindler, Daniel; Waldminghaus, Torsten

    2015-11-01

    What a living organism looks like and how it works and what are its components-all this is encoded on DNA, the genetic blueprint. Consequently, the way to change an organism is to change its genetic information. Since the first pieces of recombinant DNA have been used to transform cells in the 1970s, this approach has been enormously extended. Bigger and bigger parts of the genetic information have been exchanged or added over the years. Now we are at a point where the construction of entire chromosomes becomes a reachable goal and first examples appear. This development leads to fundamental new questions, for example, about what is possible and desirable to build or what construction rules one needs to follow when building synthetic chromosomes. Here we review the recent progress in the field, discuss current challenges and speculate on the appearance of future synthetic chromosomes. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. Chromosomal rearrangements underlying karyotype differences between Chinese pangolin (Manis pentadactyla) and Malayan pangolin (Manis javanica) revealed by chromosome painting.

    Science.gov (United States)

    Nie, Wenhui; Wang, Jinhuan; Su, Weiting; Wang, Yingxiang; Yang, Fengtang

    2009-01-01

    The Chinese pangolin (Manis pentadactyla), a representative species of the order Pholidota, has been enlisted in the mammalian whole-genome sequencing project mainly because of its phylogenetic importance. Previous studies showed that the diploid number of M. pentadactyla could vary from 2n = 36 to 42. To further characterize the genome organization of M. pentadactyla and to elucidate chromosomal mechanism underlying the karyotype diversity of Pholidota, we flow-sorted the chromosomes of 2n = 40 M. pentadactyla, and generated a set of chromosome-specific probes by DOP-PCR amplification of flow-sorted chromosomes. A comparative chromosome map between M. pentadactyla and the Malayan pangolin (Manis javanica, 2n = 38), as well as between human and M. pentadactyla, was established by chromosome painting for the first time. Our results demonstrate that seven Robertsonian rearrangements, together with considerable variations in the quantity of heterochromatin and in the number of nucleolar organizer regions (NORs) differentiate the karyotypes of 2n = 38 M. javanica and 2n = 40 M. pentadactyla. Moreover, we confirm that the M. javanica Y chromosome bears one NOR. Comparison of human homologous segment associations found in the genomes of M. javanica and M. pentadactyla revealed seven shared associations (HSA 1q/11, 2p/5, 2q/10q, 4p+q/20, 5/13, 6/19p and 8q/10p) that could constitute the potential Pholidota-specific signature rearrangements.

  7. Chromosome structure and function

    Energy Technology Data Exchange (ETDEWEB)

    Risley, M.S.

    1986-01-01

    This book presents topics in chromosome structure and function. Topics covered include: the structure of interphase chromatin; chromatin structure, gene expression and differentiation; organization of mitotic chromosomes; organization of meiotic chromosomes and synaptonimal complexes; the lampbrush chromsome of animal oocytes; dosage compensation in mammals: x chromosome inactivation; and polytene chromosomes.

  8. Rapid detection of chromosome 18 copy number in buccal smears using DNA probes and FISH

    Energy Technology Data Exchange (ETDEWEB)

    Harris, C.; Nunez, M. [Univ. of Wisconsin, WI (United States); Giraldez, R. [ONCOR, Inc., Gaithersburg, MD (United States)

    1994-09-01

    Rapid diagnosis of trisomy 18 in newborns is often critical to clinical management decisions that must be made in a minimum of time. DNA probes combined with FISH can be used to accurately to determine the copy number of chromosome 18 in interphase cells. We have used the D18Z1 alpha satellite DNA probe to determine signal frequency in normal, previously karyotyped subjects, 12 females and 6 males. We also present one clinical case of trisomy 18, confirmed by karyotype, for comparison to the results obtained from normal subjects. Buccal smears, unlike cytogenetic preparations from peripheral blood, are quite resistant to penetration of probes and detection reagents resulting in higher levels of false monosomy. We have studied 19 individuals and have obtained consistent FISH results, ranging from 64 to 90% disomy. False monosomy rates ranged from 10 to 36%, while false trisomy or tetrasomy was less than 1% in all samples. High rates of false monosomy make this test questionable for detection of low order mosaicism for monosomy, but the extremely low false hyperploidy rate suggests that this is a dependable procedure for detection of trisomy 18, enabling the use of buccal epithelium which can be collected easily from even premature and tiny infants.

  9. Pallister–Killian syndrome: Cytogenetics and molecular investigations of mosaic tetrasomy 12p in prenatal chorionic villus and in amniocytes. Strategy of prenatal diagnosis

    Directory of Open Access Journals (Sweden)

    Francesco Libotte

    2016-12-01

    Conclusion: New molecular cytogenetic techniques array comparative genomic hybridization and fluorescence in-situ hybridization in association with conventional karyotype are pivotal innovative tools to search for chromosomic anomalies and for a complete prenatal diagnosis, especially in cases such as PKS where array comparative genomic hybridization analysis alone could not show mosaicism of i(12p.

  10. Thyroid cancer GWAS identifies 10q26.12 and 6q14.1 as novel susceptibility loci and reveals genetic heterogeneity among populations.

    Science.gov (United States)

    Mancikova, Veronika; Cruz, Raquel; Inglada-Pérez, Lucía; Fernández-Rozadilla, Ceres; Landa, Iñigo; Cameselle-Teijeiro, José; Celeiro, Catuxa; Pastor, Susana; Velázquez, Antonia; Marcos, Ricard; Andía, Victor; Álvarez-Escolá, Cristina; Meoro, Amparo; Schiavi, Francesca; Opocher, Giuseppe; Quintela, Inés; Ansede-Bermejo, Juan; Ruiz-Ponte, Clara; Santisteban, Pilar; Robledo, Mercedes; Carracedo, Angel

    2015-10-15

    Thyroid cancer is the most heritable cancer of all those not displaying typical Mendelian inheritance. However, most of the genetic factors that would explain the high heritability remain unknown. Our aim was to identify additional common genetic variants associated with susceptibility to this disease. In order to do so, we performed a genome-wide association study in a series of 398 cases and 502 controls from Spain, followed by a replication in four well-defined Southern European case-control collections contributing a total of 1,422 cases and 1,908 controls. The association between the variation at the 9q22 locus near FOXE1 and thyroid cancer risk was consistent across all series, with several SNPs identified (rs7028661: OR = 1.64, p = 1.0 × 10(-22) , rs7037324: OR = 1.54, p = 1.2 × 10(-17) ). Moreover, the rare alleles of three SNPs (rs2997312, rs10788123 and rs1254167) at 10q26.12 showed suggestive evidence of association with higher risk of the disease (OR = 1.35, p = 1.2 × 10(-04) , OR = 1.26, p = 5.2 × 10(-04) and OR = 1.38, p = 5.9 × 10(-05) , respectively). Finally, the rare allele of rs4075570 at 6q14.1 conferred protection in the series studied (OR = 0.82, p = 2.0 × 10(-04) ). This study suggests that heterogeneity in genetic susceptibility between populations is a key feature to take into account when exploring genetic risk factors related to this disease. © 2015 UICC.

  11. Common variants on 2p16.1, 6p22.1 and 10q24.32 are associated with schizophrenia in Han Chinese population.

    Science.gov (United States)

    Yu, H; Yan, H; Li, J; Li, Z; Zhang, X; Ma, Y; Mei, L; Liu, C; Cai, L; Wang, Q; Zhang, F; Iwata, N; Ikeda, M; Wang, L; Lu, T; Li, M; Xu, H; Wu, X; Liu, B; Yang, J; Li, K; Lv, L; Ma, X; Wang, C; Li, L; Yang, F; Jiang, T; Shi, Y; Li, T; Zhang, D; Yue, W

    2017-07-01

    Many schizophrenia susceptibility loci have been identified through genome-wide association studies (GWASs) in European populations. However, until recently, schizophrenia GWASs in non-European populations were limited to small sample sizes and have yielded few loci associated with schizophrenia. To identify genetic risk variations for schizophrenia in the Han Chinese population, we performed a two-stage GWAS of schizophrenia comprising 4384 cases and 5770 controls, followed by independent replications of 13 single-nucleotide polymorphisms in an additional 4339 schizophrenia cases and 7043 controls of Han Chinese ancestry. Furthermore, we conducted additional analyses based on the results in the discovery stage. The combined analysis confirmed evidence of genome-wide significant associations in the Han Chinese population for three loci, at 2p16.1 (rs1051061, in an exon of VRK2, P=1.14 × 10 -12 , odds ratio (OR)=1.17), 6p22.1 (rs115070292 in an intron of GABBR1, P=4.96 × 10 -10 , OR=0.77) and 10q24.32 (rs10883795 in an intron of AS3MT, P=7.94 × 10 -10 , OR=0.87; rs10883765 at an intron of ARL3, P=3.06 × 10 -9 , OR=0.87). The polygenic risk score based on Psychiatric Genomics Consortium schizophrenia GWAS data modestly predicted case-control status in the Chinese population (Nagelkerke R 2 : 1.7% ~5.7%). Our pathway analysis suggested that neurological biological pathways such as GABAergic signaling, dopaminergic signaling, cell adhesion molecules and myelination pathways are involved in schizophrenia. These findings provide new insights into the pathogenesis of schizophrenia in the Han Chinese population. Further studies are needed to establish the biological context and potential clinical utility of these findings.

  12. The Precarious Prokaryotic Chromosome

    Science.gov (United States)

    2014-01-01

    Evolutionary selection for optimal genome preservation, replication, and expression should yield similar chromosome organizations in any type of cells. And yet, the chromosome organization is surprisingly different between eukaryotes and prokaryotes. The nuclear versus cytoplasmic accommodation of genetic material accounts for the distinct eukaryotic and prokaryotic modes of genome evolution, but it falls short of explaining the differences in the chromosome organization. I propose that the two distinct ways to organize chromosomes are driven by the differences between the global-consecutive chromosome cycle of eukaryotes and the local-concurrent chromosome cycle of prokaryotes. Specifically, progressive chromosome segregation in prokaryotes demands a single duplicon per chromosome, while other “precarious” features of the prokaryotic chromosomes can be viewed as compensations for this severe restriction. PMID:24633873

  13. Low grade mosaic for a complex supernumerary ring chromosome 18 in an adult patient with multiple congenital anomalies

    Directory of Open Access Journals (Sweden)

    Hoogeboom A Jeannette M

    2010-07-01

    Full Text Available Abstract Background Several cases have been reported of patients with a ring chromosome 18 replacing one of the normal chromosomes 18. Less common are patients with a supernumerary ring chromosomes 18. High resolution whole genome examination in patients with multiple congenital abnormalities might reveal cytogenetic abnormalities of an unexpected complexity. Results We report a 24 years old male patient with lower spinal anomalies, hypospadia, bifid scrotum, cryptorchism, anal atresia, kidney stones, urethra anomalies, radial dysplasia, and a hypoplastic thumb. Some of the anomalies overlap with the VACTERL association. Chromosome analysis of cultured peripheral blood lymphocytes revealed an additional ring chromosome in 13% of the metaphases. Both parents had a normal karyotype, demonstrating the de novo origin of this ring chromosome. FISH analysis using whole chromosome paints showed that the additional chromosomal material was derived from chromosome 18. Chromosome analysis of cultured fibroblasts revealed only one cell with the supernumerary ring chromosome in the 400 analyzed. To characterize the ring chromosome in more detail peripheral blood derived DNA was analyzed using SNP-arrays. The array results indicated a 5 Mb gain of the pericentromeric region of chromosome 18q10-q11.2. FISH analysis using BAC-probes located in the region indicated the presence of 6 signals on the r(18 chromosome. In addition, microsatellite analysis demonstrated that the unique supernumerary ring chromosome was paternally derived and both normal copies showed biparental disomy. Conclusions We report on an adult patient with multiple congenital abnormalities who had in 13% of his cells a unique supernumerary ring chromosome 18 that was composed of 6 copies of the 5 Mb gene rich region of 18q11.

  14. Sex chromosomes and sex chromosome abnormalities.

    Science.gov (United States)

    Li, Xu

    2011-12-01

    This article focuses on constitutional sex chromosome abnormalities detected by conventional cytogenetics and fluorescence in situ hybridization. The author discusses the two general classifications of abnormalities: numerical and structural. Also included are descriptions of unique aspects of X and Y chromosomes, technological advances in detection, and future perspectives.

  15. Fetal chromosome analysis: screening for chromosome disease?

    DEFF Research Database (Denmark)

    Philip, J; Tabor, Ann; Bang, J

    1983-01-01

    The aim of the study was to investigate the rationale of the current indications for fetal chromosome analysis. 5372 women had 5423 amniocentesis performed, this group constituting a consecutive sample at the chromosome laboratory, Rigshospitalet, Copenhagen from March 1973 to September 1980 (Group...... A + B). Pregnant women 35 years of age, women who previously had a chromosomally abnormal child, families with translocation carriers or other heritable chromosomal disease, families where the father was 50 years or more and women in families with a history of Down's syndrome (group A), were compared...... to women having amniocentesis, although considered not to have any increased risk of fetal chromosome abnormality (1390 pregnancies, group B). They were also compared with 750 consecutive pregnancies in women 25-34 years of age, in whom all heritable diseases were excluded (group C). The risk of unbalanced...

  16. Chromosome Disorder Outreach

    Science.gov (United States)

    ... Visit our Photo Gallery Education, Advocacy, Information & Support Chromosome Disorder Outreach, Inc is a non-profit organization. ... Inc. All Rights Reserved You are donating to : Chromosome Disorder Outreach, Inc, a 501c non-profit organization. ...

  17. Chromosome painting in plants.

    NARCIS (Netherlands)

    Schubert, I.; Fransz, P.F.; Fuchs, J.; Jong, de J.H.

    2001-01-01

    The current 'state-of-art' as to chromosome painting in plants is reviewed. We define different situations described as painting so far: i) Genomic in situ hybridisation (GISH) with total genomic DNA to distinguish alien chromosomes on the basis of divergent dispersed repeats, ii) 'Chromosomal in

  18. ZEBRAFISH CHROMOSOME-BANDING

    NARCIS (Netherlands)

    PIJNACKER, LP; FERWERDA, MA

    1995-01-01

    Banding techniques were carried out on metaphase chromosomes of zebrafish (Danio rerio) embryos. The karyotypes with the longest chromosomes consist of 12 metacentrics, 26 submetacentrics, and 12 subtelocentrics (2n = 50). All centromeres are C-band positive. Eight chromosomes have a pericentric

  19. The CEPH consortium primary linkage map of human chromosome 10.

    Science.gov (United States)

    White, R L; Lalouel, J M; Nakamura, Y; Donis-Keller, H; Green, P; Bowden, D W; Mathew, C G; Easton, D F; Robson, E B; Morton, N E

    1990-03-01

    The first CEPH consortium map, that of chromosome 10, is presented. This primary linkage map contains 28 continuously linked loci defined by genotypes generated from CEPH family DNAs with 37 probe and enzyme combinations. Cytogenetic localization of some of the genetic markers indicates that the consortium map extends, at least, from 10p13 to 10q26. The order of loci on the consortium map agrees with the physical localization data. The female map spans 309 cM (206 cM if an approximation of interference is included in the mapping function used to construct the map), and the mean genetic distance of intervals is 11 cM (7 cM). Also presented are maps of chromosome 10 from each of five CEPH collaborating laboratories, based on genotypes for all relevant markers in the CEPH database. The CEPH consortium map of chromosome 10 should be useful for localization of any gene of interest falling within the span covered. The genotypes in the chromosome 10 consortium map database are now available to the scientific community.

  20. Mapping strategies: Chromosome 16 workshop

    Energy Technology Data Exchange (ETDEWEB)

    1989-01-01

    The following topics from a workshop on chromosome 16 are briefly discussed: genetic map of chromosome 16; chromosome breakpoint map of chromosome 16; integrated physical/genetic map of chromosome 16; pulsed field map of the 16p13.2--p13.3 region (3 sheets); and a report of the HGM10 chromosome 16 committee.

  1. INTERACTION BETWEEN A CHROMOSOME 10 RET ENHANCER AND CHROMOSOME 21 IN THE DOWN SYNDROME-HIRSCHSPRUNG DISEASE ASSOCIATION

    Science.gov (United States)

    Arnold, Stacey; Pelet, Anna; Amiel, Jeanne; Borrego, Salud; Hofstra, Robert; Tam, Paul; Ceccherini, Isabella; Lyonnet, Stanislas; Sherman, Stephanie; Chakravarti, Aravinda

    2009-01-01

    Individuals with Down syndrome (DS) display a 40-fold greater risk of Hirschsprung disease (HSCR) than the general population of newborns implicating chromosome 21 in HSCR etiology. Here we demonstrate that the RET enhancer polymorphism RET+9.7 (rs2435357:C>T) at chromosome 10q11.2 is associated with HSCR in DS individuals both by transmission disequilibrium (P=0.0015) and case-control (P=0.0115) analysis of matched cases. Interestingly, the RET+9.7 T allele frequency is significantly different between individuals with DS alone (0.26±0.04), HSCR alone (0.61±0.04), and those with HSCR and DS (0.41±0.04), demonstrating an association and interaction between RET and chromosome 21 gene dosage. This is the first report of a genetic interaction between a common functional variant (rs2435357) and a not infrequent copy number error (chromosome 21 dosage) in two human developmental disorders. PMID:19306335

  2. Complex Variant t(9;22 Chromosome Translocations in Five Cases of Chronic Myeloid Leukemia

    Directory of Open Access Journals (Sweden)

    Ana Valencia

    2009-01-01

    Full Text Available The Philadelphia (Ph1 chromosome arising from the reciprocal t(9;22 translocation is found in more than 90% of chronic myeloid leukemia (CML patients and results in the formation of the chimeric fusion gene BCR-ABL. However, a small proportion of patients with CML have simple or complex variants of this translocation, involving various breakpoints in addition to 9q34 and 22q11. We report five CML cases carrying variant Ph translocations involving both chromosomes 9 and 22 as well as chromosomes 3, 5, 7, 8, or 10. G-banding showed a reciprocal three-way translocation involving 3q21, 5q31, 7q32, 8q24, and 10q22 bands. BCR-ABL fusion signal on der(22 was found in all of the cases by FISH.

  3. The Karyotype of Microsternarchus aff. bilineatus: A First Case of Y Chromosome Degeneration in Gymnotiformes.

    Science.gov (United States)

    Batista, Jéssica Almeida; Cardoso, Adauto Lima; Milhomem-Paixão, Susana Suely Rodrigues; Ready, Jonathan Stuart; Pieczarka, Julio Cesar; Nagamachi, Cleusa Yoshiko

    2017-06-01

    Various species and lineages that until recently were identified as Microsternarchus bilineatus (Hypopomidae, Gymnotiformes) have a widespread distribution in the Amazon and Orinoco River basins and across the Guiana shield. Recent molecular studies show five distinct lineages for Microsternarchus from different localities. These results suggest that this previously monotypic genus actually consists of more than one species. Here, we describe the karyotype of M. aff. bilineatus from the Cururutuia River (Bragança, Pará, Brazil). The diploid number of 48 chromosomes (14 meta-submetacentric/34 subtelo-acrocentric) is found for males and females, with an XX/XY sex chromosome system. The nucleolar organizer region is found in the short arm of pair 9. Constitutive heterochromatin occurs in the pericentromeric region of all chromosomes, in the distal region of 3p, 5p, 7p, 8q, 9q, 16q, and Xq, in the interstitial region in 2p, 10q, 11q, and 12q and all along 4p, and in a large block of the Y chromosome. These results indicate extensive karyotype divergence between this population and samples from Igarapé Tarumã Grande (Negro River, Amazonas, Brazil) studied by other researchers. Moreover, despite the diversity of sex chromosome systems found in Gymnotiformes, the XX/XY sex chromosome system of M. aff. bilineatus is the first case of Y chromosome degeneration in this order. The present data are valuable to help understand karyotype evolution in Hypopomidae.

  4. Sex Chromosome Drive

    OpenAIRE

    Helleu, Quentin; Gérard, Pierre R.; Montchamp-Moreau, Catherine

    2015-01-01

    Sex chromosome drivers are selfish elements that subvert Mendel's first law of segregation and therefore are overrepresented among the products of meiosis. The sex-biased progeny produced then fuels an extended genetic conflict between the driver and the rest of the genome. Many examples of sex chromosome drive are known, but the occurrence of this phenomenon is probably largely underestimated because of the difficulty to detect it. Remarkably, nearly all sex chromosome drivers are found in t...

  5. Chromosomal Evolution in Chiroptera

    Directory of Open Access Journals (Sweden)

    Cibele G. Sotero-Caio

    2017-10-01

    Full Text Available Chiroptera is the second largest order among mammals, with over 1300 species in 21 extant families. The group is extremely diverse in several aspects of its natural history, including dietary strategies, ecology, behavior and morphology. Bat genomes show ample chromosome diversity (from 2n = 14 to 62. As with other mammalian orders, Chiroptera is characterized by clades with low, moderate and extreme chromosomal change. In this article, we will discuss trends of karyotypic evolution within distinct bat lineages (especially Phyllostomidae, Hipposideridae and Rhinolophidae, focusing on two perspectives: evolution of genome architecture, modes of chromosomal evolution, and the use of chromosome data to resolve taxonomic problems.

  6. Chromosome analyses in dogs.

    Science.gov (United States)

    Reimann-Berg, N; Bullerdiek, J; Murua Escobar, H; Nolte, I

    2012-01-01

    Cytogenetics is the study of normal and abnormal chromosomes. Every species is characterized by a given number of chromosomes that can be recognized by their specific shape. The chromosomes are arranged according to standard classification schemes for the respective species. While pre- and postnatal chromosome analyses investigate the constitutional karyotype, tumor cytogenetics is focused on the detection of clonal acquired, tumor-associated chromosome aberrations. Cytogenetic investigations in dogs are of great value especially for breeders dealing with fertility problems within their pedigrees, for veterinarians and last but not least for the dog owners. Dogs and humans share a variety of genetic diseases, including cancer. Thus, the dog has become an increasingly important model for genetic diseases. However, cytogenetic analyses of canine cells are complicated by the complex karyotype of the dog. Only just 15 years ago, a standard classification scheme for the complete canine karyotype was established. For chromosome analyses of canine cells the same steps of chromosome preparation are used as in human cytogenetics. There are few reports about cytogenetic changes in non-neoplastic cells, involving predominantly the sex chromosomes. Cytogenetic analyses of different entities of canine tumors revealed that, comparable to human tumors, tumors of the dog are often characterized by clonal chromosome aberrations, which might be used as diagnostic and prognostic markers. The integration of modern techniques (molecular genetic approaches, adaptive computer programs) will facilitate and complete conventional cytogenetic studies. However, conventional cytogenetics is still non-replaceable.

  7. Ring chromosome 13

    DEFF Research Database (Denmark)

    Brandt, C A; Hertz, Jens Michael; Petersen, M B

    1992-01-01

    A stillborn male child with anencephaly and multiple malformations was found to have the karyotype 46,XY,r(13) (p11q21.1). The breakpoint at 13q21.1, determined by high resolution banding, is the most proximal breakpoint ever reported in patients with ring chromosome 13. In situ hybridisation...... with the probe L1.26 confirmed the derivation from chromosome 13 and DNA polymorphism analysis showed maternal origin of the ring chromosome. Our results, together with a review of previous reports of cases with ring chromosome 13 with identified breakpoints, could neither support the theory of distinct clinical...

  8. The human Y chromosome: a masculine chromosome

    NARCIS (Netherlands)

    Noordam, Michiel J.; Repping, Sjoerd

    2006-01-01

    Once considered to be a genetic wasteland of no scientific interest beyond sex determination, the human Y chromosome has made a significant comeback in the past few decades and is currently implicated in multiple diseases, including spermatogenic failure - absent or very low levels of sperm

  9. The eXtraordinarY Kids Clinic: an interdisciplinary model of care for children and adolescents with sex chromosome aneuploidy

    Directory of Open Access Journals (Sweden)

    Tartaglia N

    2015-07-01

    Full Text Available Nicole Tartaglia,1,2 Susan Howell,1,2 Rebecca Wilson,2 Jennifer Janusz,1,2 Richard Boada,1,2 Sydney Martin,2 Jacqueline B Frazier,2 Michelle Pfeiffer,2 Karen Regan,2 Sarah McSwegin,2 Philip Zeitler1,2 1Department of Pediatrics, University of Colorado School of Medicine, 2Child Development Unit, Children's Hospital Colorado, Aurora, CO, USA Purpose: Individuals with sex chromosome aneuploidies (SCAs are born with an atypical number of X and/or Y chromosomes, and present with a range of medical, developmental, educational, behavioral, and psychological concerns. Rates of SCA diagnoses in infants and children are increasing, and there is a need for specialized interdisciplinary care to address associated risks. The eXtraordinarY Kids Clinic was established to provide comprehensive and experienced care for children and adolescents with SCA, with an interdisciplinary team composed of developmental–behavioral pediatrics, endocrinology, genetic counseling, child psychology, pediatric neuropsychology, speech–language pathology, occupational therapy, nursing, and social work. The clinic model includes an interdisciplinary approach to care, where assessment results by each discipline are integrated to develop unified diagnostic impressions and treatment plans individualized for each patient. Additional objectives of the eXtraordinarY Kids Clinic program include prenatal genetic counseling, research, education, family support, and advocacy. Methods: Satisfaction surveys were distributed to 496 patients, and responses were received from 168 unique patients. Results: Satisfaction with the overall clinic visit was ranked as “very satisfied” in 85%, and as “satisfied” in another 9.8%. Results further demonstrate specific benefits from the clinic experience, the importance of a knowledgeable clinic coordinator, and support the need for similar clinics across the country. Three case examples of the interdisciplinary approach to assessment and

  10. Chromosomal mosaicism goes global

    Directory of Open Access Journals (Sweden)

    Yurov Yuri B

    2008-11-01

    Full Text Available Intercellular differences of chromosomal content in the same individual are defined as chromosomal mosaicism (alias intercellular or somatic genomic variations or, in a number of publications, mosaic aneuploidy. It has long been suggested that this phenomenon poorly contributes both to intercellular (interindividual diversity and to human disease. However, our views have recently become to change due to a series of communications demonstrated a higher incidence of chromosomal mosaicism in diseased individuals (major psychiatric disorders and autoimmune diseases as well as depicted chromosomal mosaicism contribution to genetic diversity, the central nervous system development, and aging. The later has been produced by significant achievements in the field of molecular cytogenetics. Recently, Molecular Cytogenetics has published an article by Maj Hulten and colleagues that has provided evidences for chromosomal mosaicism to underlie formation of germline aneuploidy in human female gametes using trisomy 21 (Down syndrome as a model. Since meiotic aneuploidy is suggested to be the leading genetic cause of human prenatal mortality and postnatal morbidity, these data together with previous findings define chromosomal mosaicism not as a casual finding during cytogenetic analyses but as a more significant biological phenomenon than previously recognized. Finally, the significance of chromosomal mosaicism can be drawn from the fact, that this phenomenon is involved in genetic diversity, normal and abnormal prenatal development, human diseases, aging, and meiotic aneuploidy, the intrinsic cause of which remains, as yet, unknown.

  11. Chromosomal Abnormalties with Epilepsy

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2005-02-01

    Full Text Available The correlation between specific chromosome abnormalties and various epilepsies was investigated by a study of 76 patients’ records obtained by questionnaires distributed to members of Kyoto Multi-institutional Study Group of Pediatric Neurology.

  12. Chromosomal abnormalities and autism

    Directory of Open Access Journals (Sweden)

    Farida El-Baz

    2016-01-01

    Conclusion: Chromosomal abnormalities were not detected in the studied autistic children, and so the relation between the genetics and autism still needs further work up with different study methods and techniques.

  13. Activation of X Chromosome Inactivation

    NARCIS (Netherlands)

    C.M. Maduro (Cheryl)

    2016-01-01

    markdownabstractIn mammals, males are the heterogametic sex having an X chromosome and a Y chromosome whereas females have two X chromosomes. Despite originating from an ancient homologous autosomal pair, the X and Y chromosome now differ greatly in size and gene content after ~180 MY of evolution.

  14. Vibrio chromosomes share common history

    Directory of Open Access Journals (Sweden)

    Gevers Dirk

    2010-05-01

    Full Text Available Abstract Background While most gamma proteobacteria have a single circular chromosome, Vibrionales have two circular chromosomes. Horizontal gene transfer is common among Vibrios, and in light of this genetic mobility, it is an open question to what extent the two chromosomes themselves share a common history since their formation. Results Single copy genes from each chromosome (142 genes from chromosome I and 42 genes from chromosome II were identified from 19 sequenced Vibrionales genomes and their phylogenetic comparison suggests consistent phylogenies for each chromosome. Additionally, study of the gene organization and phylogeny of the respective origins of replication confirmed the shared history. Conclusions Thus, while elements within the chromosomes may have experienced significant genetic mobility, the backbones share a common history. This allows conclusions based on multilocus sequence analysis (MLSA for one chromosome to be applied equally to both chromosomes.

  15. [Detection of complex chromosomal aberrations in patients with multiple myeloma using multiplex fluorescence in situ hybridization].

    Science.gov (United States)

    Jiang, Yuan-qiang; Chen, Li-juan; Zhu, Yu; Qiu, Hai-rong; Wang, Rong; Xu, Jia-ren; Lu, Hua; Li, Jian-yong

    2010-08-01

    To explore the value of multiplex fluorescence in situ hybridization (M-FISH) in the detection of the complex chromosomal aberrations (CCAs) in multiple myeloma (MM). M-FISH was used in 10 MM patients with CCAs detected by conventional cytogenetics (CC) using R-banding to refine the rearrangement of CCAs and identify the characteristics of marker chromosome. M-FISH confirmed the 29 structural aberrations shown by CC analysis, and also confirmed the specific source of 21 types of chromosomal aberration, which were not detected by CC analysis. Among them, t(2;15)(q33;q22), t(6;7)(q23;q34), t(8;11) (q24;q23), t(1;14)(q10;q32) and t(X;1)(q26;q25) were new chromosomal aberrations. The median survival time of 9 MM patients with CCAs was 23 months and evidently shorter than that of MM patients without CCAs, with the mean survival time being 34 months. M-FISH could refine CCAs in MM patients, find or correct the missed or misidentified abnormalities analyzed by CC. It has provided one of the essential methods for the research of chromosomal aberrations in MM.

  16. Chromosome r(10(p15.3q26.12 in a newborn child: case report

    Directory of Open Access Journals (Sweden)

    Jonasson Jon

    2009-12-01

    Full Text Available Abstract Background Ring chromosome 10 is a rare cytogenetic finding. Of the less than 10 reported cases we have found in the literature, none was characterized using high-resolution microarray analysis. Ring chromosomes are frequently unstable due to sister chromatid exchanges and mitotic failures. When mosaicism is present, the interpretation of genotype-phenotype correlations becomes extremely difficult. Results We report on a newborn girl with growth retardation, microcephaly, congenital heart defects, dysmorphic features and psychomotor retardation. Karyotyping revealed a non-mosaic apparently stable ring chromosome 10 replacing one of the normal homologues in all analyzed metaphases. High-resolution oligonucleotide microarray analysis showed a de novo approximately 12.5 Mb terminal deletion 10q26.12 -> qter and a corresponding 285 kb terminal deletion of 10pter -> p15.3. Conclusion This case demonstrates that an increased nuchal translucency thickness detected by early ultrasonography should preferably lead to not only QF-PCR for the diagnosis of Down syndrome but also karyotyping. In the future, microarray analysis, which needs further evaluation, might become the method of choice. The clinical phenotype of our patient was in agreement with that of patients with a terminal 10q deletion. For the purpose of genotype-phenotype analysis, there seems to be no need for a "ring syndrome" concept.

  17. [Y chromosome and spermatogenesis].

    Science.gov (United States)

    Ravel, C; Siffroi, J-P

    2009-01-01

    Human Y chromosome evolution has progressively been directed towards a role in sex determination and reproduction. Cytogenetically visible structural abnormalities have determined long arm chromosomal regions which define the AZF factor that contains genes implicated in the spermatogenic process. By using molecular tools, the AZF factor has been subdivided into three loci, AZFa, b and c, the deletion of which leads to specific spermatogenesis impairments due to the loss of particular genes. Most AZF genes are specifically expressed in testis but their functions are far to be known precisely. Partial deletions of AZF regions have been described. Some of them have allowed to define more precise genotype-phenotype relationships whereas others are considered as variants in relation to Y chromosome polymorphism.

  18. New Y chromosomes and early stages of sex chromosome ...

    Indian Academy of Sciences (India)

    2010-09-06

    Sep 6, 2010 ... [Traut W. 2010 New Y chromosomes and early stages of sex chromosome differentiation: sex determination in Megaselia. J. Genet. 89, ..... Schultheis C., Böhne A., Schartl M., Volff J. and Galiana-Arnoux D. 2009 Sex determination diversity and sex chromosome evolution in poeciliid fish. Sex. Dev. 3, 68–77 ...

  19. Know Your Chromosomes

    Indian Academy of Sciences (India)

    The organization of chromosomes, the structure and function of genes and the role of genetic mutations in diseases continue to be an area of intense scientific investigation. The size of an ... 39 years, while Mendel formulated his laws of inheritance 130 years ago ..... Harper International edition, Harper and Row, New York.

  20. Chromosomal abnormalities and autism

    African Journals Online (AJOL)

    Farida El-Baz

    2015-06-19

    Jun 19, 2015 ... Abstract Background: Autism is a neurodevelopmental disorder characterized by clinical, etio- logic and genetic heterogeneity. Many surveys revealed cytogenetically visible chromosomal abnor- malities in 7.4% of autistic patients documented as well as several submicroscopic variants. This study had ...

  1. Know Your Chromosomes

    Indian Academy of Sciences (India)

    a gene located on the X chromosome is expressed in males more often than in females? For most genes ..... Disease results in light sensitive skin lesions, fragile skin due to deficiency of uroporphyrinogen dicarboxylase, an enzyme involved in biosynthesis of ... Aufwomall'SctlSSlve protein. PX MPl Zellweger syndrome (ZS).

  2. The Y Chromosome

    Science.gov (United States)

    Offner, Susan

    2010-01-01

    The Y chromosome is of great interest to students and can be used to teach about many important biological concepts in addition to sex determination. This paper discusses mutation, recombination, mammalian sex determination, sex determination in general, and the evolution of sex determination in mammals. It includes a student activity that…

  3. Know Your Chromosomes

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 3. Know Your Chromosomes The Strong Holds of Family Trees. Vani Brahmachari. Series Article Volume 1 Issue 3 March 1996 pp 30-38. Fulltext. Click here to view fulltext PDF. Permanent link:

  4. Know Your Chromosomes

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 1. Know Your Chromosomes Nature's Way of Packing Genes. Vani Brahmachari. Series Article Volume 1 Issue 1 January 1996 pp 40-47. Fulltext. Click here to view fulltext PDF. Permanent link:

  5. Electochemical detection of chromosome translocation

    DEFF Research Database (Denmark)

    Kwasny, Dorota; Dimaki, Maria; Silahtaroglu, Asli

    2014-01-01

    Cytogenetics is a study of the cell structure with a main focus on chromosomes content and their structure. Chromosome abnormalities, such as translocations may cause various genetic disorders and heametological malignancies. Chromosome translocations are structural rearrangements of two...... chromosomes that results in formation of derivative chromosomes with a mixed DNA sequence. The method currently used for their detection is Fluorescent In Situ Hybridization, which requires a use of expensive, fluorescently labeled probes that target the derivative chromosomes. We present here a double...... hybridization approach developed for label-free detection of the chromosome translocations. For specific translocation detection it is necessary to determine that the two DNA sequences forming a derivative chromosome are connected, which is achieved by two subsequent hybridization steps. The electrochemical...

  6. Telomere dysfunction and chromosome instability

    Energy Technology Data Exchange (ETDEWEB)

    Murnane, John P., E-mail: jmurnane@radonc.ucsf.edu [Department of Radiation Oncology, University of California San Francisco, 2340 Sutter Street, San Francisco, CA 94143-1331 (United States)

    2012-02-01

    The ends of chromosomes are composed of a short repeat sequence and associated proteins that together form a cap, called a telomere, that keeps the ends from appearing as double-strand breaks (DSBs) and prevents chromosome fusion. The loss of telomeric repeat sequences or deficiencies in telomeric proteins can result in chromosome fusion and lead to chromosome instability. The similarity between chromosome rearrangements resulting from telomere loss and those found in cancer cells implicates telomere loss as an important mechanism for the chromosome instability contributing to human cancer. Telomere loss in cancer cells can occur through gradual shortening due to insufficient telomerase, the protein that maintains telomeres. However, cancer cells often have a high rate of spontaneous telomere loss despite the expression of telomerase, which has been proposed to result from a combination of oncogene-mediated replication stress and a deficiency in DSB repair in telomeric regions. Chromosome fusion in mammalian cells primarily involves nonhomologous end joining (NHEJ), which is the major form of DSB repair. Chromosome fusion initiates chromosome instability involving breakage-fusion-bridge (B/F/B) cycles, in which dicentric chromosomes form bridges and break as the cell attempts to divide, repeating the process in subsequent cell cycles. Fusion between sister chromatids results in large inverted repeats on the end of the chromosome, which amplify further following additional B/F/B cycles. B/F/B cycles continue until the chromosome acquires a new telomere, most often by translocation of the end of another chromosome. The instability is not confined to a chromosome that loses its telomere, because the instability is transferred to the chromosome donating a translocation. Moreover, the amplified regions are unstable and form extrachromosomal DNA that can reintegrate at new locations. Knowledge concerning the factors promoting telomere loss and its consequences is

  7. [Dicentric Y chromosome].

    Science.gov (United States)

    Abdelmoula, N Bouayed; Amouri, A

    2005-01-01

    Dicentric Y chromosomes are the most common Y structural abnormalities and their influence on gonadal and somatic development is extremely variable. Here, we report the third comprehensive review of the literature concerning dicentric Y chromosomes reported since 1994. We find 78 new cases for which molecular studies (PCR or FISH) have been widely applied to investigate SRY (68% of cases), GBY, ZFY, RFS4Y, GCY and different genes at AZF region. For dic(Yq), all cases (n = 20) were mosaic for 45,X and 4 of them were also mosaic for a 46,XY cell line. When breakpoints were available (15/20 cases), they were in Yp11. 50% of cases were phenotypic female and 20% phenotypic male while 20% of cases were reported with gonadal dysgenesis. Gonadal histology was defined in 8 cases but only in one case, gonadal tissu was genetically investigated because of gonadoblastoma. For dic(Yp) (n = 55), mosaicism concerned only 45,X cell line and was found in 50 cases while the remainder five cases were homogeneous. When breakpoints were available, it was at Yq11 in 50 cases and at Yq12 in two cases. 54% of cases were phenotypic female, 26% were phenotypic male and 18% were associated with genitalia ambiguous. SRY was analyzed in 33 cases, sequenced in 9 cases and was muted in only one case. Gonads were histologically explored in 34 cases and genetically investigated in 8 cases. Gonadoblastoma was found in only two cases. Through this review, it seems that phenotype-genotype correlations are still not possible and that homogeneous studies of dic(Y) in more patients using molecular tools for structural characterization of the rearranged Y chromosome and assessment of mosaicism in many organs are necessary to clarify the basis of the phenotypic heterogeneity of dicentric Y chromosomes and then to help phenotypic prediction of such chromosome rearrangement.

  8. A der(18)t(9;18)(p13;p11) and a der(9;18)(p10;q10) in polycythemia vera associated with a hyperproliferative phenotype in transformation to postpolycythemic myelofibrosis

    DEFF Research Database (Denmark)

    Larsen, Thomas Stauffer; Hasselbalch, Hans Carl; Pallisgaard, Niels

    2007-01-01

    harbored the JAK2 V617F mutation. Our data, together with previously published data, clearly indicate an association of these chromosomal abnormalities with a highly proliferative PV phenotype with a propensity to transform into postpolycythemic myelofibrosis. Cytogenetic analysis seems to identify...

  9. The chromosome cycle of prokaryotes

    Science.gov (United States)

    Kuzminov, Andrei

    2013-01-01

    Summary In both eukaryotes and prokaryotes, chromosomal DNA undergoes replication, condensation-decondensation and segregation, sequentially, in some fixed order. Other conditions, like sister-chromatid cohesion (SCC), may span several chromosomal events. One set of these chromosomal transactions within a single cell cycle constitutes the “chromosome cycle”. For many years it was generally assumed that the prokaryotic chromosome cycle follows major phases of the eukaryotic one: -replication-condensation-segregation-(cell division)-decondensation-, with SCC of unspecified length. Eventually it became evident that, in contrast to the strictly consecutive chromosome cycle of eukaryotes, all stages of the prokaryotic chromosome cycle run concurrently. Thus, prokaryotes practice “progressive” chromosome segregation separated from replication by a brief SCC, and all three transactions move along the chromosome at the same fast rate. In other words, in addition to replication forks, there are “segregation forks” in prokaryotic chromosomes. Moreover, the bulk of prokaryotic DNA outside the replication-segregation transition stays compacted. I consider possible origins of this concurrent replication-segregation and outline the “nucleoid administration” system that organizes the dynamic part of the prokaryotic chromosome cycle. PMID:23962352

  10. Chromosome 19 International Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Pericak-Vance, M.A. (Duke Univ., Durham, NC (United States). Medical Center); Ropers, H.H. (Univ. Hospital Nijmegen, (The Netherlands). Dept. of Human Genetics); Carrano, A.J. (Lawrence Livermore National Lab., CA (United States))

    1993-01-04

    The Second International Workshop on Human Chromosome 19 was hosted on January 25 and 26, 1992, by the Department of Human Genetics, University Hospital Nijmegen, The Netherlands, at the 'Meerdal Conference Center'. The workshop was supported by a grant from the European Community obtained through HUGO, the Dutch Research Organization (NWO) and the Muscular Dystrophy Association (MDA). Travel support for American participants was provided by the Department of Energy. The goals of this workshop were to produce genetic, physical and integrated maps of chromosome 19, to identify inconsistencies and gaps, and to discuss and exchange resources and techniques available for the completion of these maps. The second day of the meeting was largely devoted to region or disease specific efforts. In particular, the meeting served as a platform for assessing and discussing the recent progress made into the molecular elucidation of myotonic dystrophy.

  11. The X chromosome in space.

    Science.gov (United States)

    Jégu, Teddy; Aeby, Eric; Lee, Jeannie T

    2017-06-01

    Extensive 3D folding is required to package a genome into the tiny nuclear space, and this packaging must be compatible with proper gene expression. Thus, in the well-hierarchized nucleus, chromosomes occupy discrete territories and adopt specific 3D organizational structures that facilitate interactions between regulatory elements for gene expression. The mammalian X chromosome exemplifies this structure-function relationship. Recent studies have shown that, upon X-chromosome inactivation, active and inactive X chromosomes localize to different subnuclear positions and adopt distinct chromosomal architectures that reflect their activity states. Here, we review the roles of long non-coding RNAs, chromosomal organizational structures and the subnuclear localization of chromosomes as they relate to X-linked gene expression.

  12. Method for obtaining Chromosomes Method for obtaining Chromosomes

    Directory of Open Access Journals (Sweden)

    Bogart James P.

    1973-09-01

    Full Text Available It is very easy to obtain chromosomes from anuran amphibians.Amphibians have very large chromosomes which can easily be seen with an ordinary microscope. The method used has been tested in the laboratory and also at collecting sites. All that is required are a few chemicals and simple equipment.It is very easy to obtain chromosomes from anuran amphibians.Amphibians have very large chromosomes which can easily be seen with an ordinary microscope. The method used has been tested in the laboratory and also at collecting sites. All that is required are a few chemicals and simple equipment.

  13. Y chromosome morphology of cattle.

    Science.gov (United States)

    Potter, W L; Upton, P C

    1979-11-01

    Metaphase chromosomes from cultured lymphocytes were prepared from 246 bulls including Bos indicus, Bos taurus. Bos (Bibos) banteng, Sanga and interspecific and intra-specific breed crosses. Morphology and karyotype position of the Y chromosome for each bull were noted. Karyotype position of the Y chromosome varied between bulls from 25th to 29th pair and the Y chromosomes of Bos indicus and breeds derived from Bos indicus bulls were acrocentric while those of Bos taurus, Sanga and breeds derived from these bulls were metacentric/submetacentric. Two forms of Y chromosome were noted in the Droughtmaster breed. C-banding patterns of the acrocentric Y chromosome were characteristic and enabled easy identification.

  14. Intraspecific chromosome variability

    Directory of Open Access Journals (Sweden)

    N Dubinin

    2010-12-01

    Full Text Available (Editorial preface. The publication is presented in order to remind us of one of dramatic pages of the history of genetics. It re-opens for the contemporary reader a comprehensive work marking the priority change from plant cytogenetics to animal cytogenetics led by wide population studies which were conducted on Drosophila polytene chromosomes. The year of the publication (1937 became the point of irretrievable branching between the directions of Old World and New World genetics connected with the problems of chromosome variability and its significance for the evolution of the species. The famous book of T. Dobzhansky (1937 was published by Columbia University in the US under the title “Genetics and the origin of species”, and in the shadow of this American ‘skybuilding’ all other works grew dim. It is remarkable that both Dobzhansky and Dubinin come to similar conclusions about the role of chromosomes in speciation. This is not surprising given that they both might be considered as representatives of the Russian genetic school, by their birth and education. Interestingly, Dobzhansky had never referred to the full paper of Dubinin et al. (1937, though a previous short communication in Nature (1936 was included together with all former papers on the related subject. In full, the volume of the original publication printed in the Biological Journal in Moscow comprised 47 pages, in that number 41 pages of the Russian text accompanied by 16 Figs, a table and reference list, and, above all, 6 pages of the English summary. This final part in English is now reproduced in the authors’ version with the only addition being the reference list in the originally printed form.

  15. X Chromosome Evolution in Cetartiodactyla.

    Science.gov (United States)

    Proskuryakova, Anastasia A; Kulemzina, Anastasia I; Perelman, Polina L; Makunin, Alexey I; Larkin, Denis M; Farré, Marta; Kukekova, Anna V; Lynn Johnson, Jennifer; Lemskaya, Natalya A; Beklemisheva, Violetta R; Roelke-Parker, Melody E; Bellizzi, June; Ryder, Oliver A; O'Brien, Stephen J; Graphodatsky, Alexander S

    2017-08-31

    The phenomenon of a remarkable conservation of the X chromosome in eutherian mammals has been first described by Susumu Ohno in 1964. A notable exception is the cetartiodactyl X chromosome, which varies widely in morphology and G-banding pattern between species. It is hypothesized that this sex chromosome has undergone multiple rearrangements that changed the centromere position and the order of syntenic segments over the last 80 million years of Cetartiodactyla speciation. To investigate its evolution we have selected 26 evolutionarily conserved bacterial artificial chromosome (BAC) clones from the cattle CHORI-240 library evenly distributed along the cattle X chromosome. High-resolution BAC maps of the X chromosome on a representative range of cetartiodactyl species from different branches: pig (Suidae), alpaca (Camelidae), gray whale (Cetacea), hippopotamus (Hippopotamidae), Java mouse-deer (Tragulidae), pronghorn (Antilocapridae), Siberian musk deer (Moschidae), and giraffe (Giraffidae) were obtained by fluorescent in situ hybridization. To trace the X chromosome evolution during fast radiation in specious families, we performed mapping in several cervids (moose, Siberian roe deer, fallow deer, and Pere David's deer) and bovid (muskox, goat, sheep, sable antelope, and cattle) species. We have identified three major conserved synteny blocks and rearrangements in different cetartiodactyl lineages and found that the recently described phenomenon of the evolutionary new centromere emergence has taken place in the X chromosome evolution of Cetartiodactyla at least five times. We propose the structure of the putative ancestral cetartiodactyl X chromosome by reconstructing the order of syntenic segments and centromere position for key groups.

  16. Know Your Chromosomes Hybrid Cells and Human Chromosomes

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 6. Know Your Chromosomes Hybrid Cells and Human Chromosomes. Vani Brahmachari. Series Article Volume 1 Issue 6 June 1996 pp 41-49. Fulltext. Click here to view fulltext PDF. Permanent link:

  17. Chromosome Connections: Compelling Clues to Common Ancestry

    Science.gov (United States)

    Flammer, Larry

    2013-01-01

    Students compare banding patterns on hominid chromosomes and see striking evidence of their common ancestry. To test this, human chromosome no. 2 is matched with two shorter chimpanzee chromosomes, leading to the hypothesis that human chromosome 2 resulted from the fusion of the two shorter chromosomes. Students test that hypothesis by looking for…

  18. Towards positional cloning of the locus for benign neonatal epilepsy (EBN1) on chromosome 20

    Energy Technology Data Exchange (ETDEWEB)

    Schubert, S.; Laccone, F.; Hansmann, I. [Institute of Human Genetics, Goettingen (Germany)] [and others

    1994-09-01

    Benign neonatal epilepsy is characterized by tonic-clonic and generalized convulsions appearing during the neonatal period and clearing most often by the age of 2 years. EBN, a rare example of primary epilepsy, follows an autosomal dominant mode of inheritance with high penetrance. One locus for EBN (EBN1) was assigned by linkage analysis to the distal 20q segment in proximity to D20S19 and D20S20. The association of 20q sequences with seizures is also underlined by the observation that all 10 probands known with a ring 20 disclose seizures. For positional cloning of the respective locus at 20q13.3, we characterized segmental monosomy in two probands with r(20) and in one proband with a translocation t(10q;20q). The latter proband has a dicentric chromosome 10;20 with breakpoints very distally at 10q and 20q, and seizures similar to those in EBN. Segmental monosomy was investigated by FISH, Southerns and PCR for microsatellites assuming that the respective phenotype, i.e. seizures, is due to loss of 20q sequences (loss of gene function). Probes were used for D20S19, D20S20, D20S24, D20S26, D20S64, D20S102, D20S171, DS20S173, cos23D11, cos35, cos54, as well as for the genes CHRNA4, EDN3, GNAS1, KCNB1, MC3. All of these genes are reasonable candidates for EBN1, due to their function and/or expression pattern. Segmental monosomy for the distal 20q segment was disclosed in the proband with dic(10q;20q) for all loci distal from the critical marker D20S20 and including one of the above genes. In none of the two r(20) probands was any of the distal 20q-markers was found to be deleted, however. It is assumed that seizures with these probands should result from other mechanisms, e.g., by an altered function of respective genes resulting from ring formation. The gene deleted in our proband with dic(10q;20q) is a first candidate gene for EBN1 and is being investigated with respect to its significance for disease manifestation in EBN1.

  19. Chromosomal rearrangements occurred repeatedly and ...

    African Journals Online (AJOL)

    All examined Paroedura showed NORs on the smallest chromosome pair; moreover, six of the eleven examined species show a 2n = 36 karyotype, with a pair of metacentrics and 17 telocentric pair. The remaining species exhibited karyotypes with a diploid chromosome number ranging from 2n = 31 to 2n = 38. We assume ...

  20. Vibrio chromosome-specific families

    DEFF Research Database (Denmark)

    Lukjancenko, Oksana; Ussery, David

    2014-01-01

    many membrane-associated activities, such as ion channels, transmembrane transporters, and electron transport chain proteins. Thus, it appears that whilst there are many "housekeeping systems" encoded in chromosome 1, there are far fewer core functions found in chromosome 2. However, the presence...

  1. Cohesin in determining chromosome architecture

    Energy Technology Data Exchange (ETDEWEB)

    Haering, Christian H., E-mail: christian.haering@embl.de [Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg (Germany); Jessberger, Rolf, E-mail: rolf.jessberger@tu-dresden.de [Institute of Physiological Chemistry, Dresden University of Technology, Dresden (Germany)

    2012-07-15

    Cells use ring-like structured protein complexes for various tasks in DNA dynamics. The tripartite cohesin ring is particularly suited to determine chromosome architecture, for it is large and dynamic, may acquire different forms, and is involved in several distinct nuclear processes. This review focuses on cohesin's role in structuring chromosomes during mitotic and meiotic cell divisions and during interphase.

  2. Slit scan flow cytometry of isolated chromosomes following fluorescence hybridization: an approach of online screening for specific chromosomes and chromosome translocations

    NARCIS (Netherlands)

    Hausmann, M.; Dudin, G.; Aten, J. A.; Heilig, R.; Diaz, E.; Cremer, C.

    1991-01-01

    The recently developed methods of non radioactive in situ hybridization of chromosomes offer new aspects for chromosome analysis. Fluorescent labelling of hybridized chromosomes or chromosomal subregions allows to facilitate considerably the detection of specific chromosomal abnormalities. For many

  3. Chromosomal Evolution in Lower Vertebrates: Sex Chromosomes in Neotropical Fishes

    Directory of Open Access Journals (Sweden)

    Marcelo de Bello Cioffi

    2017-10-01

    Full Text Available Abstract: Fishes exhibit the greatest diversity of species among vertebrates, offering a number of relevant models for genetic and evolutionary studies. The investigation of sex chromosome differentiation is a very active and striking research area of fish cytogenetics, as fishes represent one of the most vital model groups. Neotropical fish species show an amazing variety of sex chromosome systems, where different stages of differentiation can be found, ranging from homomorphic to highly differentiated sex chromosomes. Here, we draw attention on the impact of recent developments in molecular cytogenetic analyses that helped to elucidate many unknown questions about fish sex chromosome evolution, using excellent characiform models occurring in the Neotropical region, namely the Erythrinidae family and the Triportheus genus. While in Erythrinidae distinct XY and/or multiple XY-derived sex chromosome systems have independently evolved at least four different times, representatives of Triportheus show an opposite scenario, i.e., highly conserved ZZ/ZW system with a monophyletic origin. In both cases, recent molecular approaches, such as mapping of repetitive DNA classes, comparative genomic hybridization (CGH, and whole chromosome painting (WCP, allowed us to unmask several new features linked to the molecular composition and differentiation processes of sex chromosomes in fishes.

  4. Field-flow fractionation of chromosomes

    Energy Technology Data Exchange (ETDEWEB)

    Giddings, J.C.

    1990-09-01

    Research continued on field flow fractionation of chromosomes. Progress in the past year can be organized into three main categories: (1) chromosome sample preparation; (2) preliminary chromosome fractionation; (3) fractionation of a polystyrene aggregate model which approximates the chromosome shape. We have been successful in isolating metaphase chromosomes from the Chinese hamster. We also received a human chromosome sample from Dr. Carolyn Bell-Prince of Los Alamos National Laboratory. Results are discussed. 2 figs.

  5. Mitotic chromosome condensation in vertebrates

    Energy Technology Data Exchange (ETDEWEB)

    Vagnarelli, Paola, E-mail: P.Vagnarelli@ed.ac.uk

    2012-07-15

    Work from several laboratories over the past 10-15 years has revealed that, within the interphase nucleus, chromosomes are organized into spatially distinct territories [T. Cremer, C. Cremer, Chromosome territories, nuclear architecture and gene regulation in mammalian cells, Nat. Rev. Genet. 2 (2001) 292-301 and T. Cremer, M. Cremer, S. Dietzel, S. Muller, I. Solovei, S. Fakan, Chromosome territories-a functional nuclear landscape, Curr. Opin. Cell Biol. 18 (2006) 307-316]. The overall compaction level and intranuclear location varies as a function of gene density for both entire chromosomes [J.A. Croft, J.M. Bridger, S. Boyle, P. Perry, P. Teague,W.A. Bickmore, Differences in the localization and morphology of chromosomes in the human nucleus, J. Cell Biol. 145 (1999) 1119-1131] and specific chromosomal regions [N.L. Mahy, P.E. Perry, S. Gilchrist, R.A. Baldock, W.A. Bickmore, Spatial organization of active and inactive genes and noncoding DNA within chromosome territories, J. Cell Biol. 157 (2002) 579-589] (Fig. 1A, A'). In prophase, when cyclin B activity reaches a high threshold, chromosome condensation occurs followed by Nuclear Envelope Breakdown (NEB) [1]. At this point vertebrate chromosomes appear as compact structures harboring an attachment point for the spindle microtubules physically recognizable as a primary constriction where the two sister chromatids are held together. The transition from an unshaped interphase chromosome to the highly structured mitotic chromosome (compare Figs. 1A and B) has fascinated researchers for several decades now; however a definite picture of how this process is achieved and regulated is not yet in our hands and it will require more investigation to comprehend the complete process. From a biochemical point of view a vertebrate mitotic chromosomes is composed of DNA, histone proteins (60%) and non-histone proteins (40%) [6]. I will discuss below what is known to date on the contribution of these two different classes

  6. Chromatid Painting for Chromosomal Inversion Detection Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose a novel approach to the detection of chromosomal inversions. Transmissible chromosome aberrations (translocations and inversions) have profound genetic...

  7. Chromatid Painting for Chromosomal Inversion Detection Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose the continued development of a novel approach to the detection of chromosomal inversions. Transmissible chromosome aberrations (translocations and...

  8. Regional mapping of short tandem repeats on human chromosome 10: Cytochrome P450 gene CYP2E, D10S196, D10S220, and D10S225

    Energy Technology Data Exchange (ETDEWEB)

    Koelble, K. (Univ. of Oxford (United Kingdom))

    1993-12-01

    Human CYP2E encodes an ethanol-inducible cytochrome P450 monooxygenase that metabolizes various carcinogens and may therefore play a role in cancer susceptibility. An intronic (GGAT)[sub n] [center dot] (CCTA)[sub n] repeat element was found to display limited polymorphism in Caucasoids and was used as a sequence-tagged site for genomic amplification from somatic cell hybrids to localize CYP2E to 10q24.3-qter; using the same panel, three microsatellite markers, D10S196, D10S220, and D10S225, were mapped to 10q21. The close synteny of CYP2E, CYP2C, and CYP17 belonging to two different cytochrome P450 families suggests a central role for the long arm of chromosome 10 in the evolution of this large gene superfamily. 18 refs., 2 figs.

  9. X Chromosome Evolution in Cetartiodactyla

    Science.gov (United States)

    Proskuryakova, Anastasia A.; Kulemzina, Anastasia I.; Makunin, Alexey I.; Kukekova, Anna V.; Lynn Johnson, Jennifer; Lemskaya, Natalya A.; Beklemisheva, Violetta R.; Roelke-Parker, Melody E.; Bellizzi, June; Ryder, Oliver A.; O’Brien, Stephen J.; Graphodatsky, Alexander S.

    2017-01-01

    The phenomenon of a remarkable conservation of the X chromosome in eutherian mammals has been first described by Susumu Ohno in 1964. A notable exception is the cetartiodactyl X chromosome, which varies widely in morphology and G-banding pattern between species. It is hypothesized that this sex chromosome has undergone multiple rearrangements that changed the centromere position and the order of syntenic segments over the last 80 million years of Cetartiodactyla speciation. To investigate its evolution we have selected 26 evolutionarily conserved bacterial artificial chromosome (BAC) clones from the cattle CHORI-240 library evenly distributed along the cattle X chromosome. High-resolution BAC maps of the X chromosome on a representative range of cetartiodactyl species from different branches: pig (Suidae), alpaca (Camelidae), gray whale (Cetacea), hippopotamus (Hippopotamidae), Java mouse-deer (Tragulidae), pronghorn (Antilocapridae), Siberian musk deer (Moschidae), and giraffe (Giraffidae) were obtained by fluorescent in situ hybridization. To trace the X chromosome evolution during fast radiation in specious families, we performed mapping in several cervids (moose, Siberian roe deer, fallow deer, and Pere David’s deer) and bovid (muskox, goat, sheep, sable antelope, and cattle) species. We have identified three major conserved synteny blocks and rearrangements in different cetartiodactyl lineages and found that the recently described phenomenon of the evolutionary new centromere emergence has taken place in the X chromosome evolution of Cetartiodactyla at least five times. We propose the structure of the putative ancestral cetartiodactyl X chromosome by reconstructing the order of syntenic segments and centromere position for key groups. PMID:28858207

  10. Are There Knots in Chromosomes?

    Directory of Open Access Journals (Sweden)

    Jonathan T. Siebert

    2017-08-01

    Full Text Available Recent developments have for the first time allowed the determination of three-dimensional structures of individual chromosomes and genomes in nuclei of single haploid mouse embryonic stem (ES cells based on Hi–C chromosome conformation contact data. Although these first structures have a relatively low resolution, they provide the first experimental data that can be used to study chromosome and intact genome folding. Here we further analyze these structures and provide the first evidence that G1 phase chromosomes are knotted, consistent with the fact that plots of contact probability vs sequence separation show a power law dependence that is intermediate between that of a fractal globule and an equilibrium structure.

  11. Chromosome fragility in Freemartin cattle

    Directory of Open Access Journals (Sweden)

    V. Barbieri

    2010-04-01

    Full Text Available The aim of the present study was to verify chromosome fragility in freemartin cattle using chromosome aberration (CA and sister chromatid exchange (SCE tests. A total of eighteen co-twins were investigated. Fourteen animals were identified as cytogenetically chimeric (2n=60, XX/XY while 4 were classified as normal. Freemartin cattle showed a higher percentage of aneuploid cells (18.64% and highly significant statistical differences (P < 0.001 in mean values of gaps (4.53 ± 2.05, chromatid breaks (0.26 ± 0.51, and significant statistical differences (P < 0.005 in mean values of chromosome breaks (0.12 ± 0.43 when compared to 10 control animals from single births (aneuploid cells, 11.20%; gaps, 2.01 ± 1.42; chromatid breaks, 0.05 ± 0.22; chromosome breaks, 0.02 ± 0.14.

  12. Dynamic organization of mitotic chromosomes.

    Science.gov (United States)

    Kinoshita, Kazuhisa; Hirano, Tatsuya

    2017-06-01

    The assembly of rod-shaped chromosomes during mitosis is an essential prerequisite for faithful segregation of genetic information into daughter cells. Despite the long history of chromosome research, it is only recently that we have acquired powerful approaches and crucial tools that help to unlock the secret of this seemingly complex process. In particular, in vitro assays, mammalian genetics, Hi-C analyses and computer simulations have provided valuable information during the past two years. These studies are now beginning to elucidate how the core components of mitotic chromosomes, namely, histones, topoisomerase IIα and condensins, cooperate with each other to convert very long stretches of DNA into rod-shaped chromosomes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Origin and domestication of papaya Yh chromosome

    Science.gov (United States)

    Sex in papaya is controlled by a pair of nascent sex chromosomes. Females are XX, and two slightly different Y chromosomes distinguish males (XY) and hermaphrodites (XYh). The hermaphrodite-specific region of the Yh chromosome (HSY) and its X chromosome counterpart were sequenced and analyzed previo...

  14. Numerically abnormal chromosome constitutions in humans

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-12-31

    Chapter 24, discusses numerically abnormal chromosome constitutions in humans. This involves abnormalities of human chromosome number, including polyploidy (when the number of sets of chromosomes increases) and aneuploidy (when the number of individual normal chromosomes changes). Chapter sections discuss the following chromosomal abnormalities: human triploids, imprinting and uniparental disomy, human tetraploids, hydatidiform moles, anomalies caused by chromosomal imbalance, 13 trisomy (D{sub 1} trisomy, Patau syndrome), 21 trisomy (Down syndrome), 18 trisomy syndrome (Edwards syndrome), other autosomal aneuploidy syndromes, and spontaneous abortions. The chapter concludes with remarks on the nonrandom participation of chromosomes in trisomy. 69 refs., 3 figs., 4 tabs.

  15. Inherited unbalanced structural chromosome abnormalities at prenatal chromosome analysis are rarely ascertained through recurrent miscarriage

    NARCIS (Netherlands)

    Franssen, M. T. M.; Korevaar, J. C.; Tjoa, W. M.; Leschot, N. J.; Bossuyt, P. M. M.; Knegt, A. C.; Suykerbuyk, R. F.; Hochstenbach, R.; van der Veen, F.; Goddijn, M.

    2008-01-01

    OBJECTIVE: To determine the mode of ascertainment of inherited unbalanced structural chromosome abnormalities detected at prenatal chromosome analysis. METHODS: From the databases of three centres for clinical genetics in the Netherlands, all cases of inherited unbalanced structural chromosome

  16. Inherited unbalanced structural chromosome abnormalities at prenatal chromosome analysis are rarely ascertained through recurrent miscarriage

    NARCIS (Netherlands)

    Franssen, M. T. M.; Korevaar, J. C.; Tjoa, W. M.; Leschot, N. J.; Bossuyt, P. M. M.; Knegt, A. C.; Suykerbuyk, R. F.; Hochstenbach, R.; van der Veen, F.; Goddijn, M.

    Objective To determine the mode of ascertainment of inherited unbalanced structural chromosome abnormalities detected at prenatal chromosome analysis. Methods From the databases of three centres for clinical genetics in the Netherlands, all cases of inherited unbalanced structural chromosome

  17. Radiation-induced chromosomal instability

    Energy Technology Data Exchange (ETDEWEB)

    Ritter, S. [GSI, Biophysics, Darmstadt (Germany)

    1999-03-01

    Recent studies on radiation-induced chromosomal instability in the progeny of exposed mammalian cells were briefly described as well as other related studies. For the analysis of chromosomal damage in clones, cells were seeded directly after exposure in cell well-dish to form single cell clones and post-irradiation chromosome aberrations were scored. Both exposure to isoeffective doses of X-ray or 270 MeV/u C-ions (13 keV/{mu}m) increased the number of clones with abnormal karyotype and the increase was similar for X-ray and for C-ions. Meanwhile, in the progeny of cells for mass cultures, there was no indication of a delayed expression of chromosomal damage up to 40 population doublings after the exposure. A high number of aberrant cells were only observed directly after exposure to 10.7 MeV/u O-ions, i.e. in the first cycle cells and decreased with subsequent cell divisions. The reason for these differences in the radiation-induced chromosomal instability between clonal isolates and mass culture has not been clarified. Recent studies indicated that genomic instability occurs at a high frequency in the progeny of cells irradiated with both sparsely and densely ionizing radiation. Such genomic instability is thought likely to increase the risk of carcinogenesis, but more data are required for a well understanding of the health risks resulting from radiation-induced delayed instability. (M.N.)

  18. Chromosome segregation in plant meiosis

    Directory of Open Access Journals (Sweden)

    Linda eZamariola

    2014-06-01

    Full Text Available Faithful chromosome segregation in meiosis is essential for ploidy stability over sexual life cycles. In plants, defective chromosome segregation caused by gene mutations or other factors leads to the formation of unbalanced or unreduced gametes creating aneuploid or polyploid progeny, respectively. Accurate segregation requires the coordinated execution of conserved processes occurring throughout the two meiotic cell divisions. Synapsis and recombination ensure the establishment of chiasmata that hold homologous chromosomes together allowing their correct segregation in the first meiotic division, which is also tightly regulated by cell-cycle dependent release of cohesin and monopolar attachment of sister kinetochores to microtubules. In meiosis II, bi-orientation of sister kinetochores and proper spindle orientation correctly segregate chromosomes in four haploid cells. Checkpoint mechanisms acting at kinetochores control the accuracy of kinetochore-microtubule attachment, thus ensuring the completion of segregation. Here we review the current knowledge on the processes taking place during chromosome segregation in plant meiosis, focusing on the characterization of the molecular factors involved.

  19. New Advances in Chromosome Architecture.

    Science.gov (United States)

    Leake, Mark C

    2016-01-01

    Our knowledge of the "architecture" of chromosomes has grown enormously in the past decade. This new insight has been enabled largely through advances in interdisciplinary research methods at the cutting-edge interface of the life and physical sciences. Importantly this has involved several state-of-the-art biophysical tools used in conjunction with molecular biology approaches which enable investigation of chromosome structure and function in living cells. Also, there are new and emerging interfacial science tools which enable significant improvements to the spatial and temporal resolution of quantitative measurements, such as in vivo super-resolution and powerful new single-molecule biophysics methods, which facilitate probing of dynamic chromosome processes hitherto impossible. And there are also important advances in the methods of theoretical biophysics which have enabled advances in predictive modeling of this high quality experimental data from molecular and physical biology to generate new understanding of the modes of operation of chromosomes, both in eukaryotic and prokaryotic cells. Here, I discuss these advances, and take stock on the current state of our knowledge of chromosome architecture and speculate where future advances may lead.

  20. Mechanisms for Complex Chromosomal Insertions.

    Science.gov (United States)

    Gu, Shen; Szafranski, Przemyslaw; Akdemir, Zeynep Coban; Yuan, Bo; Cooper, Mitchell L; Magriñá, Maria A; Bacino, Carlos A; Lalani, Seema R; Breman, Amy M; Smith, Janice L; Patel, Ankita; Song, Rodger H; Bi, Weimin; Cheung, Sau Wai; Carvalho, Claudia M B; Stankiewicz, Paweł; Lupski, James R

    2016-11-01

    Chromosomal insertions are genomic rearrangements with a chromosome segment inserted into a non-homologous chromosome or a non-adjacent locus on the same chromosome or the other homologue, constituting ~2% of nonrecurrent copy-number gains. Little is known about the molecular mechanisms of their formation. We identified 16 individuals with complex insertions among 56,000 individuals tested at Baylor Genetics using clinical array comparative genomic hybridization (aCGH) and fluorescence in situ hybridization (FISH). Custom high-density aCGH was performed on 10 individuals with available DNA, and breakpoint junctions were fine-mapped at nucleotide resolution by long-range PCR and DNA sequencing in 6 individuals to glean insights into potential mechanisms of formation. We observed microhomologies and templated insertions at the breakpoint junctions, resembling the breakpoint junction signatures found in complex genomic rearrangements generated by replication-based mechanism(s) with iterative template switches. In addition, we analyzed 5 families with apparently balanced insertion in one parent detected by FISH analysis and found that 3 parents had additional small copy-number variants (CNVs) at one or both sides of the inserting fragments as well as at the inserted sites. We propose that replicative repair can result in interchromosomal complex insertions generated through chromothripsis-like chromoanasynthesis involving two or three chromosomes, and cause a significant fraction of apparently balanced insertions harboring small flanking CNVs.

  1. Mechanisms for Complex Chromosomal Insertions.

    Directory of Open Access Journals (Sweden)

    Shen Gu

    2016-11-01

    Full Text Available Chromosomal insertions are genomic rearrangements with a chromosome segment inserted into a non-homologous chromosome or a non-adjacent locus on the same chromosome or the other homologue, constituting ~2% of nonrecurrent copy-number gains. Little is known about the molecular mechanisms of their formation. We identified 16 individuals with complex insertions among 56,000 individuals tested at Baylor Genetics using clinical array comparative genomic hybridization (aCGH and fluorescence in situ hybridization (FISH. Custom high-density aCGH was performed on 10 individuals with available DNA, and breakpoint junctions were fine-mapped at nucleotide resolution by long-range PCR and DNA sequencing in 6 individuals to glean insights into potential mechanisms of formation. We observed microhomologies and templated insertions at the breakpoint junctions, resembling the breakpoint junction signatures found in complex genomic rearrangements generated by replication-based mechanism(s with iterative template switches. In addition, we analyzed 5 families with apparently balanced insertion in one parent detected by FISH analysis and found that 3 parents had additional small copy-number variants (CNVs at one or both sides of the inserting fragments as well as at the inserted sites. We propose that replicative repair can result in interchromosomal complex insertions generated through chromothripsis-like chromoanasynthesis involving two or three chromosomes, and cause a significant fraction of apparently balanced insertions harboring small flanking CNVs.

  2. Dean flow fractionation of chromosomes

    Science.gov (United States)

    Hockin, Matt; Sant, Himanshu J.; Capecchi, Mario; Gale, Bruce K.

    2016-03-01

    Efforts to transfer intact mammalian chromosomes between cells have been attempted for more than 50 years with the consistent result being transfer of sub unit length pieces regardless of method. Inertial microfluidics is a new field that has shown much promise in addressing the fractionation of particles in the 2-20 μm size range (with unknown limits) and separations are based upon particles being carried by curving confined flows (within a spiral shaped, often rectangular flow chamber) and migrating to stable "equilibrium" positions of varying distance from a chamber wall depending on the balance of dean and lift forces. We fabricated spiral channels for inertial microfluidic separations using a standard soft lithography process. The concentration of chromosomes, small contaminant DNA and large cell debris in each outlets were evaluated using microscope (60X) and a flow cytometer. Using Dean Flow Fractionation, we were able to focus 4.5 times more chromosomes in outlet 2 compared to outlet 4 where most of the large debris is found. We recover 16% of the chromosomes in outlet #1- 50% in 2, 23% in 3 and 11% in 4. It should be noted that these estimates of recovery do not capture one piece of information- it actually may be that the chromosomes at each outlet are physically different and work needs to be done to verify this potential.

  3. Chromosomal Evolution in Lower Vertebrates: Sex Chromosomes in Neotropical Fishes

    Czech Academy of Sciences Publication Activity Database

    Cioffi, M. de B.; Yano, C. F.; Sember, Alexandr; Bertollo, L.A.C.

    2017-01-01

    Roč. 8, č. 10 (2017), č. článku 258. ISSN 2073-4425 R&D Projects: GA MŠk EF15_003/0000460 Institutional support: RVO:67985904 Keywords : alternative evolutionary models * simple and multiple sex chromosomes * independent and common origins Subject RIV: EG - Zoology Impact factor: 3.600, year: 2016

  4. Inheritance of a Ring Chromosome 21 in a Couple Undergoing In Vitro Fertilization (IVF: A Case Report

    Directory of Open Access Journals (Sweden)

    Roberto L. P. Mazzaschi

    2011-01-01

    Full Text Available An amniotic fluid sample from an in vitro fertilized pregnancy was referred for cytogenetic analysis based on a Down syndrome screening risk of 1 : 21. Routine cytogenetic analysis showed a nonmosaic karyotype of 46,XX,r(21(p11.2q22.3, with partial monosomy for chromosome 21 due to a ring chromosome replacing one of the normal homologues. Detailed ultrasound scanning for the remainder of the pregnancy did not reveal any unusual findings. Parental bloods showed that the mother was mosaic for the ring 21 with a karyotype of 46,XX,r(21(p11.2q22.3/46,XX and the father had an unrelated Robertsonian translocation, with a karyotype of 45,XY,rob(13;14(q10;q10. Microarray analysis of cultured amniocytes determined the extent of the deletion of chromosome 21 material in the ring. The parents were given genetic counselling, and a phenotypically normal female baby was delivered at term. This case highlights the importance of karyotyping as an initial step in the management of couples referred for in vitro fertilization.

  5. First Birth after Sperm Selection through Discontinuous Gradient Centrifugation and Artificial Insemination from a Chromosomal Translocation Carrier

    Directory of Open Access Journals (Sweden)

    Alexandre Rouen

    2014-01-01

    Full Text Available Introduction. Balanced chromosomal carriers, though usually healthy, are confronted with recurrent spontaneous abortions and malformations in the offspring. Those are related to the transmission of an abnormal, chromosomally unbalanced genotype. We evidenced that the proportion of unbalanced spermatozoa can be significantly decreased through a sperm preparation process called discontinuous gradient centrifugation (DGC. We therefore started offering intrauterine inseminations with this procedure to couples with a male translocation carriers. Case Presentation. We report the case of a 37-year-old man carrying a t(3;10(q25;p13 reciprocal translocation. He and his partner had had trouble conceiving for ten years and had four spontaneous abortions. DGC in this patient decreased the proportion of unbalanced spermatozoa from 63.6% to 52.3%. They were therefore offered intrauterine insemination with DGC, which eventually led to the birth of a healthy female child carrying the paternal translocation. Conclusion. We showed that translocation carriers could be offered intrauterine inseminations with DGC. Before this, the only two options were natural conception with prenatal diagnosis and termination of chromosomally unbalanced fetuses or preimplantation genetic diagnosis, which is a much heavier and costly procedure. We are currently offering this option through a multicentric program in France, and this is the first birth originating from it.

  6. Random search for shared chromosomal regions in four affected individuals: the assignment of a new hereditary ataxia locus

    Energy Technology Data Exchange (ETDEWEB)

    Nikali, K.; Suomalainen, A.; Koskinen, T.; Peltonen, L. [Univ. of Helsinki (Finland); Terwilliger, J. [Univ. of Oxford (United Kingdom); Weissenbach, J. [Genethon, Evry (France)

    1995-05-01

    Infantile-onset spinocerebellar ataxia (IOSCA) is an autosomal recessively inherited progressive neurological disorder of unknown etiology. This ataxia, identified so far only in the genetically isolated Finnish population, does not share gene locus with any of the previously identified hereditary ataxias, and a random mapping approach was adopted to assign the IOSCA locus. Based on the assumption of one founder mutation, a primary screening of the genome was performed using samples from just four affected individuals in two consanguineous pedigrees. The identification of a shared chromosomal region in these four patients provided the first evidence that the IOSCA gene locus is on chromosome 10q23.3-q24.1, which was confirmed by conventional linkage analysis in the complete family material. Strong linkage disequilibrium observed between IOSCA and the linked markers was utilized to define accurately the critical chromosomal region. The results showed the power of linkage disequilibrium in the locus assignment of diseases with very limited family materials. 30 refs., 3 figs., 2 tabs.

  7. Identification of chromosome abnormalities in screening of a family with manic depression and psoriasis: predisposition to aneuploidy.

    Science.gov (United States)

    Demirhan, Osman; Demirbek, Bülent; Tunç, Erdal; Uslu, Inayet Nur; Çetiner, Salih; Serin, Ayşe

    2012-06-01

    Cytogenetic analysis is an important stage in understanding the genetic background of manic depression (MD), and may provide a valuable clue to the identification of target loci and successful search for major genes. In order to identify chromosomal regions we aimed to detect the relationships between chromosomal aberrations (CAs) and immunological markers in a family with MD and psoriasis. We used the cell cultivation and conventional G-banding. We found predominantly numerical aberrations. The most common aneuploidy was chromosome 8, followed by chromosome 22, 21, 15, X and Y. However, structural aberrations consisted of duplications, deletions, translocations and breaks, with a focus on: loci on del(1)(q12-q23), del(1)(q21.1-q24), del(1)(q21.1-q23), del(10)(p11.2-pter), der(2)t(2;4)(p25;p12), t(2;22)(p14;p13), t(19;Y)? and dup(10)(q26). The susceptibility genes of MD or psoriasis may be located on these loci. Numerical sex CAs included 4(5.8%) with 45,X, 3(4.3%) with 47,XXY, and 4(5.8%) with structural chromosome X; del(X)(q13); del(X)(p11-pter) del(X)(q21.3) and inv(Y)(q11.2). We also conducted an immunological study. According results of this study, the percentage of CD2+, CD4+ and CD8+ lymphocytes of the father were significantly higher, whereas CD4+ lymphocytes were decreased in the mother, when compared the healthy persons. The percentage of CD4 level of the son was decreased, whereas CD8+ lymphocytes were higher. The CD4/CD8 ratio of the father and the son was found to be significantly high. These results may suggest that MD and psoriasis have a significant impact on both genetic and immunological parameters. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Algorithm for sorting chromosomal aberrations

    DEFF Research Database (Denmark)

    Vogel, Ida; Lund, Najaaraq; Rasmussen, Steen

    2017-01-01

    Prenatal diagnostic methods and screening procedures change rapidly in these years. Years ago only karyotyping was performed prenatally, and we monitored only Down syndrome(1) . Since then the diagnostic possibilities have increased to QF-PCR, FISH, MLPA and chromosomal microarray....

  9. Interpreting chromosomal abnormalities using Prolog.

    Science.gov (United States)

    Cooper, G; Friedman, J M

    1990-04-01

    This paper describes an expert system for interpreting the standard notation used to represent human chromosomal abnormalities, namely, the International System for Human Cytogenetic Nomenclature. Written in Prolog, this program is very powerful, easy to maintain, and portable. The system can be used as a front end to any database that employs cytogenetic notation, such as a patient registry.

  10. CHROMOSOMAL MULTIPLICITY IN BURKHOLDERIA CEPACIA

    Science.gov (United States)

    We have used CHEF gel electrophoresis to screen preparations of large DNA from different Burkholderia cepacia isolates for the presence of DNA species corresponding to the linearized forms of the three chromosomes of 3.4,2.5, and 0.9 Mb identified in B. cepacia strain 17616. DNA ...

  11. Prenatal diagnosis and molecular cytogenetic characterization of a derivative chromosome der(18;18(q10;q10del(18(q11.1q12.1del(18(q22.1q22.3 presenting as apparent isochromosome 18q in a fetus with holoprosencephaly

    Directory of Open Access Journals (Sweden)

    Chih-Ping Chen

    2011-06-01

    Conclusion: Concomitant monosomy 18p and trisomy 18q can be associated with holoprosencephaly and abnormal maternal serum screening results. Array-comparative genomic hybridization, fluorescence in situ hybridization, and quantitative fluorescent polymerase chain reaction are useful in genetic counseling of prenatally detected isochromosomes by providing information on the origin and genetic components of the isochromosome.

  12. Chromosome Aberrations by Heavy Ions

    Science.gov (United States)

    Ballarini, Francesca; Ottolenghi, Andrea

    It is well known that mammalian cells exposed to ionizing radiation can show different types of chromosome aberrations (CAs) including dicentrics, translocations, rings, deletions and complex exchanges. Chromosome aberrations are a particularly relevant endpoint in radiobiology, because they play a fundamental role in the pathways leading either to cell death, or to cell conversion to malignancy. In particular, reciprocal translocations involving pairs of specific genes are strongly correlated (and probably also causally-related) with specific tumour types; a typical example is the BCR-ABL translocation for Chronic Myeloid Leukaemia. Furthermore, aberrations can be used for applications in biodosimetry and more generally as biomarkers of exposure and risk, that is the case for cancer patients monitored during Carbon-ion therapy and astronauts exposed to space radiation. Indeed hadron therapy and astronauts' exposure to space radiation represent two of the few scenarios where human beings can be exposed to heavy ions. After a brief introduction on the main general features of chromosome aberrations, in this work we will address key aspects of the current knowledge on chromosome aberration induction, both from an experimental and from a theoretical point of view. More specifically, in vitro data will be summarized and discussed, outlining important issues such as the role of interphase death/mitotic delay and that of complex-exchange scoring. Some available in vivo data on cancer patients and astronauts will be also reported, together with possible interpretation problems. Finally, two of the few available models of chromosome aberration induction by ionizing radiation (including heavy ions) will be described and compared, focusing on the different assumptions adopted by the authors and on how these models can deal with heavy ions.

  13. Chromosome imaging by atomic force microscopy: influencing ...

    Indian Academy of Sciences (India)

    investigated factors influencing chromosome ultrastructures or species-specific ultrastructural characteristics. We studied the effects of several factors on AFM imag- ing of chromosomal ultrastructures. We found that process- ing time had little effect on chromosomal ultrastructures, but that trypsin digestion had a large effect.

  14. Morphology and structure of polytene chromosomes

    Energy Technology Data Exchange (ETDEWEB)

    Zhimulev, I.F. [Institute of Cytology and Genetics, Novosibirsk (Russian Federation)

    1996-12-31

    The morphology and structure of polytene chromosomes is the subject of this detailed volume of Advances in Genetics. Polytene chromosomes are the only interphase chromosomes that appear throughout as individual structures, and therefore offer the kind of detail of the molecular biology that geneticists need. 2869 refs., 123 figs., 27 tabs.

  15. Chromosome number and cytomorphological characterization of a ...

    African Journals Online (AJOL)

    Chromosome counts from natural populations of Abrus pulchellus in Nigeria were carried out. Tetraploid (2n = 44) chromosome number was constant in all the samples investigated. The 44 chromosomes fall into three cytomorphological categories: eight metacentric and eight submetacentric pairs, and six acrocentric pairs.

  16. Familial transmission of a ring chromosome 21

    DEFF Research Database (Denmark)

    Hertz, Jens Michael

    1987-01-01

    A ring chromosome 21 was found in a phenotypically normal mother and her son. The clinical findings in the son were bilateral retention of the testes and a slightly delayed puberty onset. Consequences of a ring formation of a chromosome 21 in phenotypically normal patients are presented...... and discussed, and the previously reported cases of familially transmitted G-group ring chromosomes are reviewed....

  17. High resolution analysis of interphase chromosome domains

    NARCIS (Netherlands)

    Visser, A. E.; Jaunin, F.; Fakan, S.; Aten, J. A.

    2000-01-01

    Chromosome territories need to be well defined at high resolution before functional aspects of chromosome organization in interphase can be explored. To visualize chromosomes by electron microscopy (EM), the DNA of Chinese hamster fibroblasts was labeled in vivo with thymidine analogue BrdU. Labeled

  18. A DNA Crosslinker Collects Mitotic Chromosomes.

    Science.gov (United States)

    Sun, Mingxuan; Heald, Rebecca

    2017-09-11

    Incorporating each set of daughter chromosomes into a single nucleus at the end of mitosis is essential for genome stability. In a recent Cell paper, Samwer et al. (2017) show that by non-covalently crosslinking DNA, BAF promotes chromosome coalescence, preventing nuclear membranes from enwrapping individual chromosomes to form micronuclei. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. A Plain English Map of the Human Chromosomes.

    Science.gov (United States)

    Offner, Susan

    1992-01-01

    Presents a chromosome map for 19 known chromosomes in human genetics. Describes the characteristics attributed to the genetic codes for each of the chromosomes and discusses the teaching applications of the chromosome map. (MDH)

  20. Sex chromosome-linked genes in plants.

    Science.gov (United States)

    Matsunaga, Sachihiro

    2006-08-01

    Recent studies of plant sex chromosome-linked genes have revealed many interesting characteristics, although there are limited reports about heteromorphic sex chromosomes in flowering plants. Sex chromosome-linked genes in angiosperms have been characterized mainly in the dioecious plant Silene latifolia. Although all such genes were isolated from transcripts of male flower buds of S. latifolia, most seem to be housekeeping genes except for the petal- and stamen-specific MADS box gene on the Y chromosome (SlAP3Y) and the male reproductive organ-specific gene on the X chromosome (MROS3X). Recent evolutionary studies have revealed at least three evolutionary strata on the X chromosome that are related to stepwise loss of recombination between the sex chromosomes. Moreover, genetic maps showed conservation of gene organization on the X chromosome in the genus Silene and substantial pericentric inversion between the X and Y chromosomes of S. latifolia during evolution. A comparison between paralogs on the sex chromosomes revealed that introns of the Y-linked genes are longer than those of X-linked paralogs. Although analyses of sex chromosome-linked genes suggest that degeneration of the Y chromosome has occurred, the Y chromosome in flowering plants remains the largest in the male genome, unlike that of mammals. Accumulation of repetitive sequences and the entire chloroplast genome on the Y chromosome appear to have contributed to this large size. However, more detailed studies will be required to help explain the basis for the fact that heteromorphic sex chromosomes in angiosperms are large.

  1. Mapping strategies: Chromosome 16 workshop. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    1989-12-31

    The following topics from a workshop on chromosome 16 are briefly discussed: genetic map of chromosome 16; chromosome breakpoint map of chromosome 16; integrated physical/genetic map of chromosome 16; pulsed field map of the 16p13.2--p13.3 region (3 sheets); and a report of the HGM10 chromosome 16 committee.

  2. Novel insights into mitotic chromosome condensation

    Science.gov (United States)

    Piskadlo, Ewa; Oliveira, Raquel A.

    2016-01-01

    The fidelity of mitosis is essential for life, and successful completion of this process relies on drastic changes in chromosome organization at the onset of nuclear division. The mechanisms that govern chromosome compaction at every cell division cycle are still far from full comprehension, yet recent studies provide novel insights into this problem, challenging classical views on mitotic chromosome assembly. Here, we briefly introduce various models for chromosome assembly and known factors involved in the condensation process (e.g. condensin complexes and topoisomerase II). We will then focus on a few selected studies that have recently brought novel insights into the mysterious way chromosomes are condensed during nuclear division. PMID:27508072

  3. Automated clinical system for chromosome analysis

    Science.gov (United States)

    Castleman, K. R.; Friedan, H. J.; Johnson, E. T.; Rennie, P. A.; Wall, R. J. (Inventor)

    1978-01-01

    An automatic chromosome analysis system is provided wherein a suitably prepared slide with chromosome spreads thereon is placed on the stage of an automated microscope. The automated microscope stage is computer operated to move the slide to enable detection of chromosome spreads on the slide. The X and Y location of each chromosome spread that is detected is stored. The computer measures the chromosomes in a spread, classifies them by group or by type and also prepares a digital karyotype image. The computer system can also prepare a patient report summarizing the result of the analysis and listing suspected abnormalities.

  4. Chromosome congression explained by nanoscale electrostatics.

    Science.gov (United States)

    Gagliardi, L John; Shain, Daniel H

    2014-02-24

    Nanoscale electrostatic microtubule disassembly forces between positively charged molecules in kinetochores and negative charges on plus ends of microtubules have been implicated in poleward chromosome motions and may also contribute to antipoleward chromosome movements. We propose that chromosome congression can be understood in terms of antipoleward nanoscale electrostatic microtubule assembly forces between negatively charged microtubule plus ends and like-charged chromosome arms, acting in conjunction with poleward microtubule disassembly forces. Several other aspects of post-attachment prometaphase chromosome motions, as well as metaphase oscillations, are consistently explained within this framework.

  5. The Hypermethylated Regions in Avian Chromosomes.

    Science.gov (United States)

    Schmid, Michael; Steinlein, Claus

    2017-01-01

    Chromosomal locations and amounts of 5-methylcytosine-rich chromosome regions were detected in the karyotypes of 13 bird species by indirect immunofluorescence using a monoclonal anti-5-methylcytosine antibody. These species belong to 7 orders and 10 families of modern (Neognathae) and primitive (Palaeognathae) birds and are characterized by macro- and microchromosomes as well as ZW sex chromosomes. In all 13 species, the hypermethylated chromosome segments are confined to constitutive heterochromatin. The chromosomal locations of hypermethylated DNA regions in the karyotypes are constant and species-specific. There is no general rule with regard to the distribution of these hypermethylated chromosome regions in the genomes of birds. In most instances, hypermethylated segments are located in the centromeric regions of chromosomes, but in the sex chromosomes, these can also be found in telomeric and interstitial postitions. In most of the species studied, the centromeric heterochromatin in many, if not all, of the microchromosomes is hypermethylated. However, in one species, the only detectable hypermethylated heterochromatic regions are located in one pair of macroautosomes and in the Z sex chromosome, but none of the microchromosomes contains visible quantities of 5-methylcytosine. The analysis of 5-methylcytosine-rich chromosome regions can be very helpful for the comparative cytogenetics of closely related species or subspecies. It also reflects the dynamic evolutionary process operating in the highly repetitive DNA of eukaryotic chromosomes. © 2017 S. Karger AG, Basel.

  6. Chromosomes aberations and enviromental factors

    Directory of Open Access Journals (Sweden)

    Marković Srđan Z.

    2017-01-01

    Full Text Available Explanation the topic: Changes in genetic material can lead to aberrant cell in the direction of disorders of cellular regulation, malignant transformation, cell death, or if the adjustment was made at the level of the reproductive cells, to genetic changes in some of the consequent off spring. The topic position in scientific/professional public: Breaking of chromosomes can occur spontaneously or can be induced. Chromatid/chromosome breakings can be induced by different environmental factors: chemicals, biological clastogenic agents, accidentally or intentionally. Conclusions: The authors suggest: - making conditions for strong respect of environmental regulations; - to use higher plants for the early detection of environmental mutagens; - create and orderly update National radionuclide database.

  7. Dynamics of chromosome segregation in Escherichia coli

    DEFF Research Database (Denmark)

    Nielsen, Henrik Jørck

    2007-01-01

    Since the 1960’es the conformation and segregation of the chromosome in Escherichia coli has been a subject of interest for many scientists. However, after 40 years of research, we still know incredibly little about how the chromosome is organized inside the cell, how it manages to duplicate...... this incredibly big molecule and separate the two daughter chromosomes and how it makes sure that the daughter cells receives one copy each. The fully extended chromosome is two orders of magnitude larger than the cell in which it is contained. Hence the chromosome is heavily compacted in the cell......, and it is obvious that structured cellular actions are required to unpack it, as required for its replication, and refold the two daughter chromosomes separately without getting them entangled in the process each generation. The intention of the study was initially to find out how the chromosome is organized...

  8. CHROMOSOMAL ABNORMALITIES IN PATIENTS WITH RECURRENT MISCARRIAGE

    Directory of Open Access Journals (Sweden)

    Daniela Mierla

    2012-06-01

    Full Text Available Chromosomal abnormalities are involved in the etiology of recurrent spontaneous pregnancy loss and sub-fertility. The purpose of this study was to determine the frequency and contribution of chromosomal abnormalities in recurrent miscarriages. The results obtained and literature review are helpful in understanding the importance of cytogenetics analysis of female infertility. To investigate the distribution of chromosomal abnormalities in the Romanian population with recurrent miscarriage, karyotype analysis by G-banding was performed from peripheral blood in 967 women infertility. Results: Chromosomal abnormalities were found to 79 women (8,17%. The percentage of chromosomal abnormalities in the studied population correlates with the data in the literature. Chromosomal abnormalities could play the important role in etiology of infertility and are more frequently detected in this group of patients compared to general population. In the infertile couples balanced chromosomal abnormalities are the main cause of spontaneous abortions.

  9. Environmental pollution, chromosomes, and health

    Science.gov (United States)

    Bell, Peter M.

    In mid-May, 1980, President Carter declared a state of emergency at the Love Canal area, near Niagara Falls, New York. The reason for this was for the U.S. to underwrite the relocation costs ($3-5 million) of some 2500 residents who, according to a report by the EPA (Environmental Protection Agency) may have suffered damaged chromosomes. These injuries were apparently caused by contact with toxic wastes that had been dumped in the area in the years prior to development for housing.That the toxic compounds exist in the Love Canal and Niagara Falls subsurface zones, including public water supplies, appears to be established fact. That the residents of the Love Canal area suffered chromosomal damage may be established fact as well. Whether or not these two findings can be linked to ill health of the residents is another matter. Recently, the EPA report has been described as having ‘close to zero scientific significance,’ and has been ‘discredited’(Science, 208, 123a, 1980). The reasons for this disparity go beyond differences of opinion, beyond possible inadequacies of the EPA study, and even beyond problems that probably will arise from future studies, including those now in the planning stages. The problem is that even if victims have easily recognizable injuries from toxic substances (injury that apparently has not occurred to Love Canal residents), medical science usually cannot show a causal relationship. Even chromosomal damage is, at best, difficult to interpret. In ideal studies of significant populations and control groups, the association of toxic chemical to chromosome damage and to cancer and birth defects is indirect and, up to now, has been shown to have little or no significance to an individual member of the exposed population.

  10. Chromosome microarrays in human reproduction.

    Science.gov (United States)

    Rajcan-Separovic, Evica

    2012-01-01

    Chromosome microarray (CMA) testing allows automatic and easy identification of large chromosomal abnormalities detectable by conventional cytogenetics as well as the detection of submicroscopic chromosomal imbalances. A PubMed search was performed in order to review the current use of CMA testing in the field of human reproduction. Articles discussing the use of CMA in the preimplantation setting, ongoing pregnancies, miscarriages and patients with reproductive disorders were considered. A high rate of concordance between conventional methods of detecting chromosomal abnormalities [e.g. fluorescence in situ hybridization (FISH), karyotyping] and CMA was reported in the prenatal setting with CMA providing more comprehensive and detailed results as it investigates the whole genome at higher resolution. In preimplantation genetic screening, CMA is replacing FISH and the selection of embryos based on CMA has already resulted in live births. For ongoing pregnancies and miscarriages, CMA eliminates tissue culture failures and artifacts and allows a quick turnaround time. The detection of submicroscopic imbalances [or copy number variants (CNVs)] is beneficial when the imbalance has a clear clinical consequence but is challenging for previously undescribed imbalances, particularly for ongoing pregnancies. Recurrent CNVs have been documented in patients with reproductive disorders; however, the application of CMA in this field is still limited. CMA enhances reproductive medicine as it facilitates better understanding of the genetic aspects of human development and reproduction and more informed patient management. Further clinical validation of CMA in the prenatal setting, creation of practice guidelines and catalogs of newly discovered submicroscopic imbalances with clinical outcomes are areas that will require attention in the future.

  11. Microdissection and chromosome painting of the alien chromosome in an addition line of wheat-Thinopyrum intermedium

    Science.gov (United States)

    The chromosome painting is an efficient tool for chromosome research. However, plant chromosome painting is relatively underdeveloped. In this study, chromosome painting was developed and used to identify alien chromosomes in TAi-27, a wheat-Thinopyrum intermedium addition line, and chromosomes of...

  12. Chromosome aberration assays in Allium

    Energy Technology Data Exchange (ETDEWEB)

    Grant, W.F.

    1982-01-01

    The common onion (Allium cepa) is an excellent plant for the assay of chromosome aberrations after chemical treatment. Other species of Allium (A. cepa var. proliferum, A. carinatum, A. fistulosum and A. sativum) have also been used but to a much lesser extent. Protocols have been given for using root tips from either bulbs or seeds of Allium cepa to study the cytological end-points, such as chromosome breaks and exchanges, which follow the testing of chemicals in somatic cells. It is considered that both mitotic and meiotic end-points should be used to a greater extent in assaying the cytogenetic effects of a chemical. From a literature survey, 148 chemicals are tabulated that have been assayed in 164 Allium tests for their clastogenic effect. Of the 164 assays which have been carried out, 75 are reported as giving a positive reaction, 49 positive and with a dose response, 1 positive and temperature-related, 9 borderline positive, and 30 negative; 76% of the chemicals gave a definite positive response. It is proposed that the Allium test be included among those tests routinely used for assessing chromosomal damage induced by chemicals.

  13. De Novo Chromosome Structure Prediction

    Science.gov (United States)

    di Pierro, Michele; Cheng, Ryan R.; Lieberman-Aiden, Erez; Wolynes, Peter G.; Onuchic, Jose'n.

    Chromatin consists of DNA and hundreds of proteins that interact with the genetic material. In vivo, chromatin folds into nonrandom structures. The physical mechanism leading to these characteristic conformations, however, remains poorly understood. We recently introduced MiChroM, a model that generates chromosome conformations by using the idea that chromatin can be subdivided into types based on its biochemical interactions. Here we extend and complete our previous finding by showing that structural chromatin types can be inferred from ChIP-Seq data. Chromatin types, which are distinct from DNA sequence, are partially epigenetically controlled and change during cell differentiation, thus constituting a link between epigenetics, chromosomal organization, and cell development. We show that, for GM12878 lymphoblastoid cells we are able to predict accurate chromosome structures with the only input of genomic data. The degree of accuracy achieved by our prediction supports the viability of the proposed physical mechanism of chromatin folding and makes the computational model a powerful tool for future investigations.

  14. Mechanisms of Chromosome Congression during Mitosis

    Directory of Open Access Journals (Sweden)

    Helder Maiato

    2017-02-01

    Full Text Available Chromosome congression during prometaphase culminates with the establishment of a metaphase plate, a hallmark of mitosis in metazoans. Classical views resulting from more than 100 years of research on this topic have attempted to explain chromosome congression based on the balance between opposing pulling and/or pushing forces that reach an equilibrium near the spindle equator. However, in mammalian cells, chromosome bi-orientation and force balance at kinetochores are not required for chromosome congression, whereas the mechanisms of chromosome congression are not necessarily involved in the maintenance of chromosome alignment after congression. Thus, chromosome congression and maintenance of alignment are determined by different principles. Moreover, it is now clear that not all chromosomes use the same mechanism for congressing to the spindle equator. Those chromosomes that are favorably positioned between both poles when the nuclear envelope breaks down use the so-called “direct congression” pathway in which chromosomes align after bi-orientation and the establishment of end-on kinetochore-microtubule attachments. This favors the balanced action of kinetochore pulling forces and polar ejection forces along chromosome arms that drive chromosome oscillatory movements during and after congression. The other pathway, which we call “peripheral congression”, is independent of end-on kinetochore microtubule-attachments and relies on the dominant and coordinated action of the kinetochore motors Dynein and Centromere Protein E (CENP-E that mediate the lateral transport of peripheral chromosomes along microtubules, first towards the poles and subsequently towards the equator. How the opposite polarities of kinetochore motors are regulated in space and time to drive congression of peripheral chromosomes only now starts to be understood. This appears to be regulated by position-dependent phosphorylation of both Dynein and CENP-E and by spindle

  15. Chromosomal divergence and evolutionary inferences in Rhodniini based on the chromosomal location of ribosomal genes

    Directory of Open Access Journals (Sweden)

    Sebastian Pita

    2013-05-01

    Full Text Available In this study, we used fluorescence in situ hybridisation to determine the chromosomal location of 45S rDNA clusters in 10 species of the tribe Rhodniini (Hemiptera: Reduviidae: Triatominae. The results showed striking inter and intraspecific variability, with the location of the rDNA clusters restricted to sex chromosomes with two patterns: either on one (X chromosome or both sex chromosomes (X and Y chromosomes. This variation occurs within a genus that has an unchanging diploid chromosome number (2n = 22, including 20 autosomes and 2 sex chromosomes and a similar chromosome size and genomic DNA content, reflecting a genome dynamic not revealed by these chromosome traits. The rDNA variation in closely related species and the intraspecific polymorphism in Rhodnius ecuadoriensis suggested that the chromosomal position of rDNA clusters might be a useful marker to identify recently diverged species or populations. We discuss the ancestral position of ribosomal genes in the tribe Rhodniini and the possible mechanisms involved in the variation of the rDNA clusters, including the loss of rDNA loci on the Y chromosome, transposition and ectopic pairing. The last two processes involve chromosomal exchanges between both sex chromosomes, in contrast to the widely accepted idea that the achiasmatic sex chromosomes of Heteroptera do not interchange sequences.

  16. Complex X-Chromosomal Rearrangements in Two Women with Ovarian Dysfunction: Implications of Chromothripsis/Chromoanasynthesis-Dependent and -Independent Origins of Complex Genomic Alterations.

    Science.gov (United States)

    Suzuki, Erina; Shima, Hirohito; Toki, Machiko; Hanew, Kunihiko; Matsubara, Keiko; Kurahashi, Hiroki; Narumi, Satoshi; Ogata, Tsutomu; Kamimaki, Tsutomu; Fukami, Maki

    2016-01-01

    Our current understanding of the phenotypic consequences and the molecular basis of germline complex chromosomal rearrangements remains fragmentary. Here, we report the clinical and molecular characteristics of 2 women with germline complex X-chromosomal rearrangements. Patient 1 presented with nonsyndromic ovarian dysfunction and hyperthyroidism; patient 2 exhibited various Turner syndrome- associated symptoms including ovarian dysfunction, short stature, and autoimmune hypothyroidism. The genomic abnormalities of the patients were characterized by array-based comparative genomic hybridization, high-resolution karyotyping, microsatellite genotyping, X-inactivation analysis, and bisulfite sequencing. Patient 1 carried a rearrangement of unknown parental origin with a 46,X,der(X)(pter→ p22.1::p11.23→q24::q21.3→q24::p11.4→pter) karyotype, indicative of a catastrophic chromosomal reconstruction due to chromothripsis/chromoanasynthesis. Patient 2 had a paternally derived isochromosome with a 46,X,der(X)(pter→ p22.31::q22.1→q10::q10→q22.1::p22.31→pter) karyotype, which likely resulted from 2 independent, sequential events. Both patients showed completely skewed X inactivation. CpG sites at Xp22.3 were hypermethylated in patient 2. The results indicate that germline complex X-chromosomal rearrangements underlie nonsyndromic ovarian dysfunction and Turner syndrome. Disease-causative mechanisms of these rearrangements likely include aberrant DNA methylation, in addition to X-chromosomal mispairing and haploinsufficiency of genes escaping X inactivation. Notably, our data imply that germline complex X-chromosomal rearrangements are created through both chromothripsis/chromoanasynthesis-dependent and -independent processes. © 2017 S. Karger AG, Basel.

  17. Chromosome analysis of arsenic affected cattle

    Directory of Open Access Journals (Sweden)

    S. Shekhar

    2014-10-01

    Full Text Available Aim: The aim was to study the chromosome analysis of arsenic affected cattle. Materials and Methods: 27 female cattle (21 arsenic affected and 6 normal were selected for cytogenetical study. The blood samples were collected, incubated, and cultured using appropriate media and specific methods. The samples were analyzed for chromosome number and morphology, relative length of the chromosome, arm ratio, and centromere index of X chromosome and chromosomal abnormalities in arsenic affected cattle to that of normal ones. Results: The diploid number of metaphase chromosomes in arsenic affected cattle as well as in normal cattle were all 2n=60, 58 being autosomes and 2 being sex chromosomes. From the centromeric position, karyotyping studies revealed that all the 29 pair of autosomes was found to be acrocentric or telocentric, and the sex chromosomes (XX were submetacentric in both normal and arsenic affected cattle. The relative length of all the autosome pairs and sex chrosomosome pair was found to be higher in normal than that of arsenic affected cattle. The mean arm ratio of X-chromosome was higher in normal than that of arsenic affected cattle, but it is reverse in case of centromere index value of X-chromosome. There was no significant difference of arm ratio and centromere index of X-chromosomes between arsenic affected and normal cattle. No chromosomal abnormalities were found in arsenic affected cattle. Conclusion: The chromosome analysis of arsenic affected cattle in West Bengal reported for the first time in this present study which may serve as a guideline for future studies in other species. These reference values will also help in comparison of cytological studies of arsenic affected cattle to that of various toxicants.

  18. Deciphering evolutionary strata on plant sex chromosomes and fungal mating-type chromosomes through compositional segmentation.

    Science.gov (United States)

    Pandey, Ravi S; Azad, Rajeev K

    2016-03-01

    Sex chromosomes have evolved from a pair of homologous autosomes which differentiated into sex determination systems, such as XY or ZW system, as a consequence of successive recombination suppression between the gametologous chromosomes. Identifying the regions of recombination suppression, namely, the "evolutionary strata", is central to understanding the history and dynamics of sex chromosome evolution. Evolution of sex chromosomes as a consequence of serial recombination suppressions is well-studied for mammals and birds, but not for plants, although 48 dioecious plants have already been reported. Only two plants Silene latifolia and papaya have been studied until now for the presence of evolutionary strata on their X chromosomes, made possible by the sequencing of sex-linked genes on both the X and Y chromosomes, which is a requirement of all current methods that determine stratum structure based on the comparison of gametologous sex chromosomes. To circumvent this limitation and detect strata even if only the sequence of sex chromosome in the homogametic sex (i.e. X or Z chromosome) is available, we have developed an integrated segmentation and clustering method. In application to gene sequences on the papaya X chromosome and protein-coding sequences on the S. latifolia X chromosome, our method could decipher all known evolutionary strata, as reported by previous studies. Our method, after validating on known strata on the papaya and S. latifolia X chromosome, was applied to the chromosome 19 of Populus trichocarpa, an incipient sex chromosome, deciphering two, yet unknown, evolutionary strata. In addition, we applied this approach to the recently sequenced sex chromosome V of the brown alga Ectocarpus sp. that has a haploid sex determination system (UV system) recovering the sex determining and pseudoautosomal regions, and then to the mating-type chromosomes of an anther-smut fungus Microbotryum lychnidis-dioicae predicting five strata in the non

  19. Scaling Chromosomes for an Evolutionary Karyotype: A Chromosomal Tradeoff between Size and Number across Woody Species.

    Science.gov (United States)

    Liang, Guolu; Chen, Hong

    2015-01-01

    This study aims to examine the expected scaling relationships between chromosome size and number across woody species and to clarify the importance of the scaling for the maintenance of chromosome diversity by analyzing the scaling at the inter- & intra-chromosomal level. To achieve for the goals, chromosome trait data were extracted for 191 woody species (including 56 evergreen species and 135 deciduous species) from the available literature. Cross-species analyses revealed a tradeoff among chromosomes between chromosome size and number, demonstrating there is selective mechanism crossing chromosomes among woody species. And the explanations for the result were presented from intra- to inter-chromosome contexts that the scaling may be compromises among scale symmetry, mechanical requirements, and resource allocation across chromosomes. Therein, a 3/4 scaling pattern was observed between total chromosomes and m-chromosomes within nucleus which may imply total chromosomes may evolve from more to less. In addition, the primary evolutionary trend of karyotype and the role of m-chromosomes in the process of karyotype evolution were also discussed.

  20. SMC complexes: from DNA to chromosomes.

    Science.gov (United States)

    Uhlmann, Frank

    2016-07-01

    SMC (structural maintenance of chromosomes) complexes - which include condensin, cohesin and the SMC5-SMC6 complex - are major components of chromosomes in all living organisms, from bacteria to humans. These ring-shaped protein machines, which are powered by ATP hydrolysis, topologically encircle DNA. With their ability to hold more than one strand of DNA together, SMC complexes control a plethora of chromosomal activities. Notable among these are chromosome condensation and sister chromatid cohesion. Moreover, SMC complexes have an important role in DNA repair. Recent mechanistic insight into the function and regulation of these universal chromosomal machines enables us to propose molecular models of chromosome structure, dynamics and function, illuminating one of the fundamental entities in biology.

  1. Genetically determined chromosome instability syndromes.

    Science.gov (United States)

    Schroeder, T M

    1982-01-01

    Spontaneously increased chromosomal instability is well documented in the three autosomal recessive diseases, Fanconi's anemia (FA), Bloom's syndrome (BS), and ataxia telangiectasia (AT). Other conditions have been reported to be associated with chromosomal breakage. Some are still single observations: in Werner's syndrome only fibroblasts are affected, and systemic sclerosis may not be an inherited disease. Various aspects of FA, BS, and AT are discussed which have emerged since recent reviews have been published. The differential diagnosis in FA has become more important than it was in the past. Proven heterogeneity in FA demands definition of what to name FA and FA variants. The analysis of cancer frequencies and types in FA and AT lacks important clues. This should stimulate all of us to mutual exchange of data and creation of registries not only of patients and follow-ups, but also of characterized cell strains. A synopsis of results from cell and cytogenetic studies demonstrates similarities and differences in detail of the general phenomenon of chromosomal instability which FA, BS, and AT share. Results from biochemical studies at the DNA level together with cytogenetic findings indicate different but still undefined failures in DNA metabolism or DNA repair mechanisms due to the different genes. A new approach to analyzing the impairment of DNA repair in FA is briefly described. DNA related enzymes are produced in the cytoplasm and have to be transported to the nucleus. The subcellular distribution of topoisomerase activity was found to be unusual in three placentas of FA patients. Other DNA enzymes were distributed normally. Thus, a specific mechanism for movement of the enzyme through the nuclear membrane seems to be defective.

  2. Chromosomal rearrangements in Tourette syndrome

    DEFF Research Database (Denmark)

    Bertelsen, Birgitte; Debes, Nanette Mol; Hjermind, Lena E

    2013-01-01

    Tourette syndrome (TS) is a childhood-onset complex neurobiological disorder characterized by a combination of persistent motor and vocal tics and frequent presence of other neuropsychiatric comorbidities. TS shares the fate of other complex disorders, where the genetic etiology is largely unknown...... been an efficient tool for the cloning of disease genes in several Mendelian disorders and in a number of complex disorders. Through cytogenetic investigation of 205 TS patients, we identified three possibly disease-associated chromosome rearrangements rendering this approach relevant in chasing TS...

  3. Deletion of chromosome 13 in Moebius syndrome.

    Science.gov (United States)

    Slee, J J; Smart, R D; Viljoen, D L

    1991-01-01

    A girl aged 2 1/2 years with Moebius syndrome was found to have a deletion of band q12.2 in chromosome 13 (46,XX,del(13)(q12.2]. This is the second report concerning involvement of chromosome 13q and Moebius syndrome. The observation raises the possibility that a gene responsible for Moebius syndrome is located in this region of chromosome 13. Images PMID:1870098

  4. Deletion of chromosome 13 in Moebius syndrome.

    OpenAIRE

    Slee, J J; Smart, R D; Viljoen, D L

    1991-01-01

    A girl aged 2 1/2 years with Moebius syndrome was found to have a deletion of band q12.2 in chromosome 13 (46,XX,del(13)(q12.2]. This is the second report concerning involvement of chromosome 13q and Moebius syndrome. The observation raises the possibility that a gene responsible for Moebius syndrome is located in this region of chromosome 13.

  5. AB26. Y chromosome and male infertility

    OpenAIRE

    Iijima, Masashi

    2014-01-01

    In infertile couples, a male contribution to infertility is found in 45-50%. The cause of male factor infertility remains largely unexplained, but varicocele and genetic disorder are recognized as major causes leading to spermatogenesis disability. Genetic disorder leads to male infertility include chromosomal abnormalities and Y chromosome microdeletions. Chromosomal abnormalities (numerical or structural abnormalities) can be detected routine karyotype analysis. In non-obstructed azoospemia...

  6. Y chromosome haplogroups in autistic subjects

    OpenAIRE

    Jamain, Stéphane; Quach, Hélène; Quintana-Murci, Luis; Betancur, Catalina; Philippe, Anne; Gillberg, Christopher; Sponheim, Eili; Skjeldal, Ola H.; Fellous, Marc; Leboyer, Marion; Bourgeron, Thomas

    2002-01-01

    The male to female ratio in autism is 4:1 in the global autistic population, but increases to 23:1 in autistic subjects without physical or brain abnormalities. 1 Despite this well-recognised gender difference, male predisposition to autistic disorder remains unexplained and the role of sex chromosomes is still debated. Numerical and structural abnormalities of the sex chromosomes are among the most frequently reported chromosomal disorders associated with autism. However, genome scans have f...

  7. Giemsa C-banding of Barley Chromosomes. IV. Chromosomal Constitution of Autotetraploid Barley

    DEFF Research Database (Denmark)

    Linde-Laursen, Ib

    1984-01-01

    The progeny of an autotetraploid barley plant (C1) consisted of 45 tetraploids and 33 aneuploids. Giemsa C-banding was used to identify each of the chromosomes in 20 euploid and 31 aneuploid C2--seedlings, and in 11 C3--offspring of aneuploid C2--plants. The euploid C2--seedlings all had four...... homologues of each of the chromosomes. The aneuploid C2--seedlings were fairly equally distributed on hypo-and hyperploids, and on the seven chromosome groups. This suggests that a particular chromosome is lost or gained at random in gametes and embryos. The 11 C3--seedlings comprised seven true euploids......, one seedling with 2n=28 having an extra chromosome 6 and missing one chromosome 3, and three seedlings with 2n=29. The chromosomal composition of aneuploid C3--seedlings did not reflect that of their aneuploid C2--parents with respect to missing or extra chromosomes. Two hypohexaploid C2--seedlings...

  8. New Y chromosomes and early stages of sex chromosome differentiation: sex determination in Megaselia.

    Science.gov (United States)

    Traut, Walther

    2010-09-01

    The phorid fly Megaselia scalaris is a laboratory model for the turnover and early differentiation of sex chromosomes. Isolates from the field have an XY sex-determining mechanism with chromosome pair 2 acting as X and Y chromosomes. The sex chromosomes are homomorphic but display early signs of sex chromosome differentiation: a low level of molecular differences between X and Y. The male-determining function (M), maps to the distal part of the Y chromosome's short arm. In laboratory cultures, new Y chromosomes with no signs of a molecular differentiation arise at a low rate, probably by transposition of M to these chromosomes. Downstream of the primary signal, the homologue of the Drosophila doublesex (dsx) is part of the sex-determining pathway while Sex-lethal (Sxl), though structurally conserved, is not.

  9. Maternal mosaicism of sex chromosome causes discordant sex chromosomal aneuploidies associated with noninvasive prenatal testing

    Directory of Open Access Journals (Sweden)

    Leilei Wang

    2015-10-01

    Conclusion: Our findings indicated that maternal mosaicism of sex chromosome could cause discordant sex chromosomal aneuploidies associated with NIPT. We highly recommended that maternal karyotype should be confirmed for the cases with abnormal results in NIPT.

  10. Identification of a susceptibility locus for severe adolescent idiopathic scoliosis on chromosome 17q24.3.

    Directory of Open Access Journals (Sweden)

    Atsushi Miyake

    Full Text Available Adolescent idiopathic scoliosis (AIS is the most common spinal deformity, affecting around 2% of adolescents worldwide. Genetic factors play an important role in its etiology. Using a genome-wide association study (GWAS, we recently identified novel AIS susceptibility loci on chromosomes 10q24.31 and 6q24.1. To identify more AIS susceptibility loci relating to its severity and progression, we performed GWAS by limiting the case subjects to those with severe AIS. Through a two-stage association study using a total of ∼12,000 Japanese subjects, we identified a common variant, rs12946942 that showed a significant association with severe AIS in the recessive model (P=4.00 × 10(-8, odds ratio [OR]=2.05. Its association was replicated in a Chinese population (combined P=6.43 × 10(-12, OR = 2.21. rs12946942 is on chromosome 17q24.3 near the genes SOX9 and KCNJ2, which when mutated cause scoliosis phenotypes. Our findings will offer new insight into the etiology and progression of AIS.

  11. Structure and function of eukaryotic chromosomes

    Energy Technology Data Exchange (ETDEWEB)

    Hennig, W.

    1987-01-01

    Contents: Introduction; Polytene Chromosomel Giant Chromosomes in Ciliates; The sp-I Genes in the Balbiani Rings of Chironomus Salivary Glands; The White Locus of Drosophila Melanogaster; The Genetic and Molecular Organization of the Dense Cluster of Functionally Related Vital Genes in the DOPA Decarboxylase Region of the Drosophila melanogaster Genome; Heat Shock Puffs and Response to Environmental Stress; The Y Chromosomal Lampbrush Loops of Drosophila; Contributions of Electron Microscopic Spreading Preparations (''Miller Spreads'') to the Analysis of Chromosome Structure; Replication of DNA in Eukaryotic Chromosomes; Gene Amplification in Dipteran Chromosomes; The Significance of Plant Transposable Elements in Biologically Relevant Processes; Arrangement of Chromosomes in Interphase Cell Nuclei; Heterochromatin and the Phenomenon of Chromosome Banding; Multiple Nonhistone Protein-DNA Complexes in Chromatin Regulate the Cell- and Stage-Specific Activity of an Eukaryotic Gene; Genetics of Sex Determination in Eukaryotes; Application of Basic Chromosome Research in Biotechnology and Medicine. This book presents an overview of various aspects of chromosome research.

  12. The Y chromosomes of the great apes.

    Science.gov (United States)

    Hallast, Pille; Jobling, Mark A

    2017-05-01

    The great apes (orangutans, gorillas, chimpanzees, bonobos and humans) descended from a common ancestor around 13 million years ago, and since then their sex chromosomes have followed very different evolutionary paths. While great-ape X chromosomes are highly conserved, their Y chromosomes, reflecting the general lability and degeneration of this male-specific part of the genome since its early mammalian origin, have evolved rapidly both between and within species. Understanding great-ape Y chromosome structure, gene content and diversity would provide a valuable evolutionary context for the human Y, and would also illuminate sex-biased behaviours, and the effects of the evolutionary pressures exerted by different mating strategies on this male-specific part of the genome. High-quality Y-chromosome sequences are available for human and chimpanzee (and low-quality for gorilla). The chromosomes differ in size, sequence organisation and content, and while retaining a relatively stable set of ancestral single-copy genes, show considerable variation in content and copy number of ampliconic multi-copy genes. Studies of Y-chromosome diversity in other great apes are relatively undeveloped compared to those in humans, but have nevertheless provided insights into speciation, dispersal, and mating patterns. Future studies, including data from larger sample sizes of wild-born and geographically well-defined individuals, and full Y-chromosome sequences from bonobos, gorillas and orangutans, promise to further our understanding of population histories, male-biased behaviours, mutation processes, and the functions of Y-chromosomal genes.

  13. [Chromosome breakage syndrome and fragile X syndrome].

    Science.gov (United States)

    Shiraishi, Y

    1995-11-01

    Chromosome instability is a characteristic cytogenetic feature of a number of genetically determined human disorders collectively known as chromosome breakage syndromes. Included among the disorders are Bloom's syndrome (BS), Fanconi's anemia (FA), ataxia telangiectasia (AT). In each of the syndromes chromosome instability exists in the form of increased frequencies of breaks and interchanges occurring either spontaneously or following treatment with various DNA-damaging agents. These diseases have in common an autosomal recessive transmission and an increased tendency to develop malignancies. The blood cells of subjects with AT, BS, or FA are significantly more radiosensitive than those of controls, particularly in the occurrence of chromosome aberrations.

  14. Movement of chromosomes with severed kinetochore microtubules.

    Science.gov (United States)

    Forer, Arthur; Johansen, Kristen M; Johansen, Jørgen

    2015-05-01

    Experiments dating from 1966 and thereafter showed that anaphase chromosomes continued to move poleward after their kinetochore microtubules were severed by ultraviolet microbeam irradiation. These observations were initially met with scepticism as they contradicted the prevailing view that kinetochore fibre microtubules pulled chromosomes to the pole. However, recent experiments using visible light laser microbeam irradiations have corroborated these earlier experiments as anaphase chromosomes again were shown to move poleward after their kinetochore microtubules were severed. Thus, multiple independent studies using different techniques have shown that chromosomes can indeed move poleward without direct microtubule connections to the pole, with only a kinetochore 'stub' of microtubules. An issue not yet settled is: what propels the disconnected chromosome? There are two not necessarily mutually exclusive proposals in the literature: (1) chromosome movement is propelled by the kinetochore stub interacting with non-kinetochore microtubules and (2) chromosome movement is propelled by a spindle matrix acting on the stub. In this review, we summarise the data indicating that chromosomes can move with severed kinetochore microtubules and we discuss proposed mechanisms for chromosome movement with severed kinetochore microtubules.

  15. Chromosomal replicons of higher plants

    Energy Technology Data Exchange (ETDEWEB)

    Van' t Hof, J.

    1987-03-16

    This brief discussion of replicons of higher plants offers a glimpse into the properties of chromosomal DNA replication. It gives evidence that the S phase of unrelated plant species is comprised of temporally ordered replicon families that increase in number with genome size. This orderly process, which assures a normal inheritance of genetic material to recipient daughter cells, is maintained at the level of replicon clusters by two mutually exclusive mechanisms, one involving the rate at which single replicons replicate their allotment of DNA, and another by means of the tempo-pause. The same two mechanisms are used by cells to alter the pattern of chromosomal DNA replication just prior to and during normal development. Both mechanisms are genetically determined and produce genetic effects when disturbed of disrupted by additional non-conforming DNAs. Further insight into how these two mechanisms operate requires more molecular information about the nature of replicons and the factors that govern when a replicon family replicates. Plant material is a rich and ideal source for this information just awaiting exploitation. 63 refs.

  16. Increased chromosome radiosensitivity during pregnancy

    Energy Technology Data Exchange (ETDEWEB)

    Ricoul, Michelle; Sabatier, Laure; Dutrillaux, Bernard [Commissariat a l`Energie Atomique, Laboratoire de Radiobiologie et Oncologie, DRR, DSV, Fontenay aux roses (France)

    1997-03-04

    It was necessary to consider the risks of exposure of pregnant women, not only in relation to the child, but also in relation to their own hypersensitivity. We have demonstrated that pregnancy increases radiosensitivity of chromosome in the mouse at the end of gestation. This is of importance since it may have implications on radioprotection of pregnant women and give experimental guidelines to the problems of hypersensitivity to drugs and cancer aggravation during pregnancy. Blood obtained from women at various times of pregnancy was exposed to ionizing radiations. By comparison to non-pregnant women, an increase in chromosome breakage was observed in metaphases from lymphocytes, after short-term culture in the presence of the serum of the same donor. Immediately after delivery, this increase in radiosensitivity disappeared. In a prospective study, serial analyses showed a very strong correlation between the amount of pregnancy hormones, progesterone in particular, and the increase in radiosensitivity. Pregnant women may have an increased sensitivity to ionizing radiation during the second half of their pregnancy. This study provides the first evidence in human that radiosensitivity may vary in relation to physiological conditions.

  17. Stabilization of chromosomes by DNA intercalators for flow karyotyping and identification by banding of isolated chromosomes

    NARCIS (Netherlands)

    Aten, J. A.; Buys, C. H.; van der Veen, A. Y.; Mesa, J. R.; Yu, L. C.; Gray, J. W.; Osinga, J.; Stap, J.

    1987-01-01

    A number of structurally unrelated DNA intercalators have been studied as stabilizers of mitotic chromosomes during isolation from rodent and human metaphase cells. Seven out of the nine intercalators tested were found to be useful as chromosome stabilizing agents. Chromosome suspensions prepared in

  18. Exchange of core chromosomes and horizontal transfer of lineage-specific chromosomes in Fusarium oxysporum

    NARCIS (Netherlands)

    Vlaardingerbroek, I.; Beerens, B.; Rose, L.; Fokkens, L.; Cornelissen, B.J.C.; Rep, M.

    2016-01-01

    Horizontal transfer of supernumerary or lineage-specific (LS) chromosomes has been described in a number of plant pathogenic filamentous fungi. So far it was not known whether transfer is restricted to chromosomes of certain size or properties, or whether 'core' chromosomes can also undergo

  19. [Frequency of chromosome variants in human populations].

    Science.gov (United States)

    Kuleshov, N P; Kulieva, L M

    1979-01-01

    Chromosome variants were analyzed in the course of the population chromosome investigation of 6000 newborns and clinical cytogenetic studies of 403 married couples with recurrent spontaneous abortions, stillbirths or offsprings having congenital malformations or Down's syndrome. The following variants were determined: 1) Igh+, 9gh+, 16gh+ - the enlargement of the secondary constrictions of the size, more than 1/4 of the long arm of the chromosome; 2) Dp+ or Gp+ - the enlargement of the short arms of acrocentrics, their size being more than the short arm of the chromosome 18; 3) Ds+ or Gs - large satellites of the acrocentrics which are equal or more than the thickness of the chromatids of the long arms; 4) Es+ - satellites on the short arms of the chromosomes 17 or 18; 5) Dss of Gss - double satellites; 6) Yq+ - the enlargement of the long arm of Y chromosome, the size of which being more than G chromosome; 7) Yq- - deletion of the long arm of Y chromosome, the size of the long arm being less than chromosomes 21--22. The total frequency of variants in newborns was 12.8/1000 births. The incidence of different types of variants per 1000 births was as follows: Igh+ - 0.33; 9gh+ - 0.17; 16gh+ - 0.50; Ds+ - 2.33; Dp+ - 1.50; Dp- - 0.17; Gs+ - 0.83; Gp+ - 2.17; Yq+ - 6.91/1000 males; Yg- - 0.99/1000 males; double variants - 0.33; other variants - 0.33. 4.0% of married couples with recurrent spontaneous abortions had major chromosome aberrations, 14.6% - extreme variants of chromosomes. Among 113 couples with the history of congenital malformations in their offsprings major chromosome abnormalities were found in 4.4%, chromosome variants - 13.3%. The frequency of chromosome variants among 139 patients with Down's syndrome was 7.2%. In one case Robertsonian translocation t(DqGa) was determined. The most frequent types of variant chromosomes were Ds+, Dp+, Es+, Yq+.

  20. Chromosomal painting and ZW sex chromosomes differentiation in Characidium (Characiformes, Crenuchidae

    Directory of Open Access Journals (Sweden)

    Artoni Roberto F

    2011-07-01

    Full Text Available Abstract Background The Characidium (a Neotropical fish group have a conserved diploid number (2n = 50, but show remarkable differences among species and populations in relation to sex chromosome systems and location of nucleolus organizer regions (NOR. In this study, we isolated a W-specific probe for the Characidium and characterized six Characidium species/populations using cytogenetic procedures. We analyzed the origin and differentiation of sex and NOR-bearing chromosomes by chromosome painting in populations of Characidium to reveal their evolution, phylogeny, and biogeography. Results A W-specific probe for efficient chromosome painting was isolated by microdissection and degenerate oligonucleotide primed-polymerase chain reaction (DOP-PCR amplification of W chromosomes from C. gomesi. The W probe generated weak signals dispersed on the proto sex chromosomes in C. zebra, dispersed signals in both W and Z chromosomes in C. lauroi and, in C. gomesi populations revealed a proximal site on the long arms of the Z chromosome and the entire W chromosome. All populations showed small terminal W probe sites in some autosomes. The 18S rDNA revealed distinctive patterns for each analyzed species/population with regard to proto sex chromosome, sex chromosome pair, and autosome location. Conclusions The results from dual-color fluorescence in situ hybridization (dual-color FISH using W and 18S rDNA probes allowed us to infer the putative evolutionary pathways for the differentiation of sex chromosomes and NORs, from structural rearrangements in a sex proto-chromosome, followed by gene erosion and heterochromatin amplification, morphological differentiation of the sex chromosomal pair, and NOR transposition, giving rise to the distinctive patterns observed among species/populations of Characidium. Biogeographic isolation and differentiation of sex chromosomes seem to have played a major role in the speciation process in this group of fish.

  1. How to Protect the Chromosomal Ends?

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 15; Issue 6. How to Protect the Chromosomal Ends? - Telomerase, Chromosome Stability and Aging. Anurag N Paranjape Annapoorni Rangarajan. General Article Volume 15 Issue 6 June 2010 pp 538-547 ...

  2. X-chromosome inactivation and escape

    Indian Academy of Sciences (India)

    2015-11-06

    Nov 6, 2015 ... She predicted many of the features of X inactivation, for e.g., .... feature that locks silencing, i.e. DNA methylation at CpG islands of X-linked ..... 1996 XIST RNA paints the inactive X chromosome at interphase: evidence for a novel RNA involved in nuclear/chromosome structure. J. Cell Biol. 132, 259–275.

  3. Chromosome studies in Cashew ( Anacardium occidentale L ...

    African Journals Online (AJOL)

    Chromosome studies in Cashew (Anacardium occidentale L.) OM Aliyu, JA Awopetu. Abstract. Despite the increased cultivation of cashew as a commodity crop in sub-Sahara Africa, Asia and South America there are few chromosome studies on it. The present study investigates number, structure and behavior of ...

  4. Determination of chromosomal ploidy in Agave ssp.

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-19

    Oct 19, 2009 ... (2008) analyzed the karyotypes of several agave cul- tivars. Doughty (1936) reported the chromosomal ploidies of three varieties. However, little is known about the chromosome numbers of wild and local breeding. *Corresponding author. E-mail: lianzi9381@yahoo.com.cn. Tel: (+86)13922727215.

  5. Chromosome number9 specific repetitive DNA sequence

    Energy Technology Data Exchange (ETDEWEB)

    Joste, N.E.; Cram, L.S.; Hildebrand, C.E.; Jones, M.; Longmire, J.; Robinson, T.; Moyzis, R.K.

    1986-05-01

    Human repetitive DNA libraries have been constructed and various recombinant DNA clones isolated that are likely candidates for chromosome specific sequences. The first clone tested (pHuR 98; plasmid human repeat 98) was biotinylated and hybridized to human chromosomes in situ. The hybridized recombinant probe was detected with fluoresceinated avidin, and chromosomes were counter-stained with either propidium iodide or distamycin-DAPI. Specific hybridization to chromosome band 9q1 was obtained. The localization was confirmed by hybridizing radiolabeled pHuR 98 DNA to human chromosomes sorted by flow cytometry. Various methods, including orthogonal field pulsed gel electrophoresis analysis indicate that 75 kilobase blocks of this sequence are interspersed with other repetitive DNA sequences in this chromosome band. This study is the first to report a human repetitive DNA sequence uniquely localized to a specific chromosome. This clone provides an easily detected and highly specific chromosomal marker for molecular cytogenetic analyses in numerous basic research and clinical studies.

  6. Genomic regulatory landscapes and chromosomal rearrangements

    DEFF Research Database (Denmark)

    Ladegaard, Elisabete L Engenheiro

    2008-01-01

    specificity of the individual CNEs. In this PhD study I have studied several chromosomal rearrangements with breakpoints in the vicinity of trans-dev genes. This included chromosomal rearrangements compatible with known phenotype-genotype associations (Rieger syndrome-PITX2, Mowat-Wilson syndrome-ZEB2...

  7. [CHROMOSOMAL ABNORMALITIES IN PATIENTS WITH INFERTILITY].

    Science.gov (United States)

    Pylyp, L Y; Spinenko, L O; Verhoglyad, N V; Kashevarova, O O; Zukin, V D

    2015-01-01

    To assess the frequency and structure of chromosomal abnormalities in patients with infertility, a retrospective analysis of cytogenetic studies of 3414 patients (1741 females and 1673 males), referred to the Clinic of reproductive medicine "Nadiya" from 2007 to 2012, was performed. Chromosomal abnormalities were detected in 2.37% patients: 2.79% in males and 1.95% in females. Balanced structural chromosomal abnormalities prevailed over numerical abnormalities and corresponded to 80.2% of all chromosomal abnormalities detected in the studied group. Sex chromosome abnormalities made up 23.5% of chromosomal pathology (19/81) and included gonosomal aneuploidies in 84% of cases (16/19) and structural abnormalities of chromosome Y in 16% of cases (3/19). The low level sex chromosome mosaicism was detected with the frequency of 0.55%. Our results highlight the importance of cytogenetic studies in patients seeking infertility treatment by assisted reproductive technologies, since an abnormal finding not only provide a firm diagnosis to couples with infertility, but also influences significantly the approach to infertility treatment in such patients.

  8. Y chromosome haplogroups in autistic subjects.

    Science.gov (United States)

    Jamain, S; Quach, H; Quintana-Murci, L; Betancur, C; Philippe, A; Gillberg, C; Sponheim, E; Skjeldal, O H; Fellous, M; Leboyer, M; Bourgeron, T

    2002-01-01

    The male to female ratio in autism is 4:1 in the global autistic population, but increases to 23:1 in autistic subjects without physical or brain abnormalities.(1) Despite this well-recognised gender difference, male predisposition to autistic disorder remains unexplained and the role of sex chromosomes is still debated. Numerical and structural abnormalities of the sex chromosomes are among the most frequently reported chromosomal disorders associated with autism. However, genome scans have failed to detect linkage on the X chromosome(2,3,4) and this approach cannot study the non-recombining region of the Y chromosome. In this study, we searched for a specific Y chromosome effect in autistic subjects. Using informative Y-polymorphic markers, the Y chromosome haplotypes of 111 autistic subjects from France, Sweden and Norway were defined and compared with relevant control populations. No significant difference in Y-haplotype distribution between the affected and control groups was observed. Although this study cannot exclude the presence of a Y susceptibility gene, our results are not suggestive of a Y chromosome effect in autism.

  9. Human male meiotic sex chromosome inactivation.

    NARCIS (Netherlands)

    Vries, M. de; Vosters, S.; Merkx, G.F.M.; Hauwers, K.W.M. d'; Wansink, D.G.; Ramos, L.; Boer, P. de

    2012-01-01

    In mammalian male gametogenesis the sex chromosomes are distinctive in both gene activity and epigenetic strategy. At first meiotic prophase the heteromorphic X and Y chromosomes are placed in a separate chromatin domain called the XY body. In this process, X,Y chromatin becomes highly

  10. Chromosome number and cytomorphological characterization of a ...

    African Journals Online (AJOL)

    Owner

    mistaken identity of species in earlier chromosome counts. Observations on chromosome morphology and size made in this study are an insight into what will be expected at meiosis. Distribution of several morphological categories namely acrocentrics, metacentrics and submetacentrics occurring in different size regimes as.

  11. Chromosomal Aneuploidies and Early Embryonic Developmental Arrest

    Directory of Open Access Journals (Sweden)

    Maria Maurer

    2015-07-01

    Full Text Available Background: Selecting the best embryo for transfer, with the highest chance of achieving a vital pregnancy, is a major goal in current in vitro fertilization (IVF technology. The high rate of embryonic developmental arrest during IVF treatment is one of the limitations in achieving this goal. Chromosomal abnormalities are possibly linked with chromosomal arrest and selection against abnormal fertilization products. The objective of this study was to evaluate the frequency and type of chromosomal abnormalities in preimplantation embryos with developmental arrest. Materials and Methods: This cohort study included blastomeres of embryos with early developmental arrest that were biopsied and analyzed by fluorescence in-situ hybridization (FISH with probes for chromosomes 13, 16, 18, 21 and 22. Forty-five couples undergoing IVF treatment were included, and 119 arrested embryos were biopsied. All probes were obtained from the Kinderwunsch Zentrum, Linz, Austria, between August 2009 and August 2011. Results: Of these embryos, 31.6% were normal for all chromosomes tested, and 68.4% were abnormal. Eleven embryos were uniformly aneuploid, 20 were polyploid, 3 were haploid, 11 displayed mosaicism and 22 embryos exhibited chaotic chromosomal complement. Conclusion: Nearly 70% of arrested embryos exhibit chromosomal errors, making chromosomal abnormalities a major cause of embryonic arrest and may be a further explanation for the high developmental failure rates during culture of the embryos in the IVF setting.

  12. The Barley Chromosome 5 Linkage Map

    DEFF Research Database (Denmark)

    Jensen, J.; Jørgensen, Jørgen Helms

    1975-01-01

    The literature is surveyed for data on recombination between loci on chromosome 5 of barley; 13 loci fall into the category “mapped” loci, more than 20 into the category “associated” loci and nine into the category “loci once suggested to be on chromosome 5”. A procedure was developed...

  13. CHROMOSOME STUDY OF SOME GRASSHOPPER SPECIES ...

    African Journals Online (AJOL)

    Hence, this research is aimed at studying the chromosomes of some Ethiopian grasshopper species. The grasshopper specimens used in this study were collected from eight localities in central Ethiopia. The specimens were identified as belonging to two families (Acrididae and Tetrigidae). Chromosome preparations were ...

  14. Translocations used to generate chromosome segment duplications ...

    Indian Academy of Sciences (India)

    Supplementary figure 1. (a–i) Putative novel genes created by the breakpoints. Translocation chromosomes are shown with the translocated segment indicated in red and the untranslocated segments in black or blue. Purple arrows indicate whether the chromosome is a donor (arrow pointing up) or a recipient (arrow ...

  15. Translocations used to generate chromosome segment duplications ...

    Indian Academy of Sciences (India)

    progeny bearing a duplication (Dp) of the translocated chromosome segment. Here, 30 ... [Singh P K, Iyer V S, Sowjanya T N, Raj B K and Kasbekar D P 2010 Translocations used to generate chromosome segment duplications in. Neurospora can ... of this work, namely, the definition of breakpoint junction sequences of 12 ...

  16. A sexy spin on nonrandom chromosome segregation.

    Science.gov (United States)

    Charville, Gregory W; Rando, Thomas A

    2013-06-06

    Nonrandom chromosome segregation is an intriguing phenomenon linked to certain asymmetric stem cell divisions. In a recent report in Nature, Yadlapalli and Yamashita (2013) observe nonrandom segregation of X and Y chromosomes in Drosophila germline stem cells and shed light on the complex mechanisms of this fascinating process. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Role of chromosomal instability in cancer progression.

    Science.gov (United States)

    McClelland, Sarah E

    2017-09-01

    Cancer cells often display chromosomal instability (CIN), a defect that involves loss or rearrangement of the cell's genetic material - chromosomes - during cell division. This process results in the generation of aneuploidy, a deviation from the haploid number of chromosomes, and structural alterations of chromosomes in over 90% of solid tumours and many haematological cancers. This trait is unique to cancer cells as normal cells in the body generally strictly maintain the correct number and structure of chromosomes. This key difference between cancer and normal cells has led to two important hypotheses: (i) cancer cells have had to overcome inherent barriers to changes in chromosomes that are not tolerated in non-cancer cells and (ii) CIN represents a cancer-specific target to allow the specific elimination of cancer cells from the body. To exploit these hypotheses and design novel approaches to treat cancer, a full understanding of the mechanisms driving CIN and how CIN contributes to cancer progression is required. Here, we will discuss the possible mechanisms driving chromosomal instability, how CIN may contribute to the progression at multiple stages of tumour evolution and possible future therapeutic directions based on targeting cancer chromosomal instability. © 2017 Society for Endocrinology.

  18. Cat-eye syndrome with unusual marker chromosome probably not chromosome 22.

    Science.gov (United States)

    Rosenfeld, W; Verma, R S; Jhaveri, R C

    1984-05-01

    An unusual supernumerary chromosome with a single satellite on the long arm was found in a child with manifestations of the cat-eye syndrome including apparently low-set and malformed ears, preauricular tags, micrognathia, and imperforate anus. Although G-banding suggested that this extra material was chromosome 22, this was not confirmed by several other banding techniques. After examination of the parents' chromosomes, the nature and origin of this extra chromosome remains obscure. We conclude that patients previously diagnosed as having "partial trisomy 22" with incomplete cat-eye syndrome may have a different chromosome constitution when studied by various banding techniques.

  19. Advances in understanding paternally transmitted Chromosomal Abnormalities

    Energy Technology Data Exchange (ETDEWEB)

    Marchetti, F; Sloter, E; Wyrobek, A J

    2001-03-01

    Multicolor FISH has been adapted for detecting the major types of chromosomal abnormalities in human sperm including aneuploidies for clinically-relevant chromosomes, chromosomal aberrations including breaks and rearrangements, and other numerical abnormalities. The various sperm FISH assays have been used to evaluate healthy men, men of advanced age, and men who have received mutagenic cancer therapy. The mouse has also been used as a model to investigate the mechanism of paternally transmitted genetic damage. Sperm FISH for the mouse has been used to detect chromosomally abnormal mouse sperm, while the PAINT/DAPI analysis of mouse zygotes has been used to evaluate the types of chromosomal defects that can be paternally transmitted to the embryo and their effects on embryonic development.

  20. Flow Analysis and Sorting of Plant Chromosomes.

    Science.gov (United States)

    Vrána, Jan; Cápal, Petr; Šimková, Hana; Karafiátová, Miroslava; Čížková, Jana; Doležel, Jaroslav

    2016-10-10

    Analysis and sorting of plant chromosomes (plant flow cytogenetics) is a special application of flow cytometry in plant genomics and its success depends critically on sample quality. This unit describes the methodology in a stepwise manner, starting with the induction of cell cycle synchrony and accumulation of dividing cells in mitotic metaphase, and continues with the preparation of suspensions of intact mitotic chromosomes, flow analysis and sorting of chromosomes, and finally processing of the sorted chromosomes. Each step of the protocol is described in detail as some procedures have not been used widely. Supporting histograms are presented as well as hints on dealing with plant material; the utility of sorted chromosomes for plant genomics is also discussed. © 2016 by John Wiley & Sons, Inc. Copyright © 2016 John Wiley & Sons, Inc.

  1. B chromosomes: from cytogenetics to systems biology.

    Science.gov (United States)

    Valente, Guilherme T; Nakajima, Rafael T; Fantinatti, Bruno E A; Marques, Diego F; Almeida, Rodrigo O; Simões, Rafael P; Martins, Cesar

    2017-02-01

    Though hundreds to thousands of reports have described the distribution of B chromosomes among diverse eukaryote groups, a comprehensive theory of their biological role has not yet clearly emerged. B chromosomes are classically understood as a sea of repetitive DNA sequences that are poor in genes and are maintained by a parasitic-drive mechanism during cell division. Recent developments in high-throughput DNA/RNA analyses have increased the resolution of B chromosome biology beyond those of classical and molecular cytogenetic methods; B chromosomes contain many transcriptionally active sequences, including genes, and can modulate the activity of autosomal genes. Furthermore, the most recent knowledge obtained from omics analyses, which is associated with a systemic view, has demonstrated that B chromosomes can influence cell biology in a complex way, possibly favoring their own maintenance and perpetuation.

  2. Energy Landscapes of Folding Chromosomes

    Science.gov (United States)

    Zhang, Bin

    The genome, the blueprint of life, contains nearly all the information needed to build and maintain an entire organism. A comprehensive understanding of the genome is of paramount interest to human health and will advance progress in many areas, including life sciences, medicine, and biotechnology. The overarching goal of my research is to understand the structure-dynamics-function relationships of the human genome. In this talk, I will be presenting our efforts in moving towards that goal, with a particular emphasis on studying the three-dimensional organization, the structure of the genome with multi-scale approaches. Specifically, I will discuss the reconstruction of genome structures at both interphase and metaphase by making use of data from chromosome conformation capture experiments. Computationally modeling of chromatin fiber at atomistic level from first principles will also be presented as our effort for studying the genome structure from bottom up.

  3. Chromosomal context and replication properties of ARS plasmids in ...

    Indian Academy of Sciences (India)

    ARS) elements function as plasmid as well as chromosomal replication origins in yeasts. As compared to ARSs, different chromosomal origins vary greatly in their efficiency and timing of replication probably due to their wider chromosomal ...

  4. Meiotic cohesin-based chromosome structure is essential for homologous chromosome pairing in Schizosaccharomyces pombe.

    Science.gov (United States)

    Ding, Da-Qiao; Matsuda, Atsushi; Okamasa, Kasumi; Nagahama, Yuki; Haraguchi, Tokuko; Hiraoka, Yasushi

    2016-06-01

    Chromosome structure is dramatically altered upon entering meiosis to establish chromosomal architectures necessary for the successful progression of meiosis-specific events. An early meiotic event involves the replacement of the non-SMC mitotic cohesins with their meiotic equivalents in most part of the chromosome, forming an axis on meiotic chromosomes. We previously demonstrated that the meiotic cohesin complex is required for chromosome compaction during meiotic prophase in the fission yeast Schizosaccharomyces pombe. These studies revealed that chromosomes are elongated in the absence of the meiotic cohesin subunit Rec8 and shortened in the absence of the cohesin-associated protein Pds5. In this study, using super-resolution structured illumination microscopy, we found that Rec8 forms a linear axis on chromosomes, which is required for the organized axial structure of chromatin during meiotic prophase. In the absence of Pds5, the Rec8 axis is shortened whereas chromosomes are widened. In rec8 or pds5 mutants, the frequency of homologous chromosome pairing is reduced. Thus, Rec8 and Pds5 play an essential role in building a platform to support the chromosome architecture necessary for the spatial alignment of homologous chromosomes.

  5. Elucidation of structural abnormalities of the X chromosome using fluorescence in situ hybridisation with a Y chromosome painting probe.

    OpenAIRE

    Howell, R T; Millener, R; Thorne, S; O'Loughlin, J; Brassey, J; McDermott, A

    1994-01-01

    Particular regions of the X and Y chromosomes share DNA sequence homology to the extent that cross hybridisation occurs. Thus, chromosome painting with a whole Y chromosome probe consistently results in fluorescence on specific regions of the X chromosome as well as the complete Y chromosome. This phenomenon has been exploited to elucidate the structure of unusual X chromosome rearrangements, without Y involvement, in two females.

  6. Scaling behaviors of CG clusters for chromosomes

    Energy Technology Data Exchange (ETDEWEB)

    Cheng Jun [Department of Physics, Wenzhou Normal College, Wenzhou 325027 (China); Department of Physics, Jinhua University, Jinhua 321017 (China); Zhang Linxi [Department of Physics, Wenzhou Normal College, Wenzhou 325027 (China)]. E-mail: lxzhang@hzcnc.com

    2005-07-01

    In this paper we adopt a new method to study the scaling behaviors of CG clusters in different organism chromosomes. The statistical distributions of CG and AT clusters for different chromosomes have the same scaling behaviors, i.e. P(S){proportional_to}e{sup -{alpha}}{sup S}. The values of {alpha} are very close to each other for the same organism chromosomes, and depend on different organism chromosomes. We also find that the parameter {xi}(m)={sigma}(m)m of CG cluster complies with the good power law {xi}(m){proportional_to}m{sup -{gamma}}. Here {sigma}(m)=2-, and m is the number of bases in consecutive, non-overlapping blocks. The values of {gamma} have the same behavior as the values of {alpha} in statistical distributions of P(S){proportional_to}e{sup -{alpha}}{sup S}. Meanwhile, we also consider the relationship between the values of {gamma} and the percentage of cluster CG content for different organism chromosomes, and there are some relations between them. These investigations provide some insights into the nucleotide clusters of chromosomes, and help us understand DNA sequences of chromosomes.

  7. Nonrandom chromosomal changes in human malignant cells

    Energy Technology Data Exchange (ETDEWEB)

    Rowley, J D

    1977-01-01

    The role of chromosomal changes in human malignant cells has been the subject of much debate. The observation of nonrandom chromosomal changes has become well recognized in chronic myelogenous leukemia, and more recently in acute myelogenous leukemia. In the present report, data are presented on the sites of duplication of chromosome No. 1 in hematologic disorders. Trisomy for region lq25 to lq32 was observed in every one of 34 patients whose cells showed duplication of some part of chromosome No. 1. Adjacent regions lq21 to lq25, and lq32 to lqter, also were trisomic in the majority of patients. Two patients had deletions, one of lq32 to qter, and the other, of lp32 to pter. The sites of chromosomal breaks leading to trisomy differ from those involved in balanced reciprocal translocations. Some of these sites are sometimes, but not always, vulnerable in constitutional chromosomal abnormalities. The nature of the proliferative advantage conferred on myeloid cells by these chromosomal changes is unknown.

  8. [Y chromosome structural abnormalities and Turner's syndrome].

    Science.gov (United States)

    Ravel, C; Siffroi, J-P

    2009-06-01

    Although specifically male, the human Y chromosome may be observed in female karyotypes, mostly in women with Turner syndrome stigmata. In women with isolated gonadal dysgenesis but otherwise normal stature, the testis determining factor or SRY gene may have been removed from the Y chromosome or may be mutated. In other women with Turner syndrome, the karyotype is usually abnormal and shows a frequent 45,X/46,XY mosaicism. In these cases, the phenotype depends on the ratio between Y positive and 45,X cell lines in the body. When in mosaicism, Y chromosomes are likely to carry structural abnormalities which explain mitotic instability, such as the existence of two centromeres. Dicentric Y isochromosomes for the short arm (idic[Yp]) or ring Y chromosomes (r[Y]) are the most frequent abnormal Y chromosomes found in infertile patients and in Turner syndrome in mosaic with 45,X cells. Although monocentric, deleted Y chromosomes for the long arm and those carrying microdeletions in the AZF region are also instable and are frequently associated with a 45,X cell line. Management of infertile patients carrying such abnormal Y chromosomes must take into account the risk and the consequences of a mosaicism in the offspring.

  9. Structure of the human chromosome interaction network.

    Directory of Open Access Journals (Sweden)

    Sergio Sarnataro

    Full Text Available New Hi-C technologies have revealed that chromosomes have a complex network of spatial contacts in the cell nucleus of higher organisms, whose organisation is only partially understood. Here, we investigate the structure of such a network in human GM12878 cells, to derive a large scale picture of nuclear architecture. We find that the intensity of intra-chromosomal interactions is power-law distributed. Inter-chromosomal interactions are two orders of magnitude weaker and exponentially distributed, yet they are not randomly arranged along the genomic sequence. Intra-chromosomal contacts broadly occur between epigenomically homologous regions, whereas inter-chromosomal contacts are especially associated with regions rich in highly expressed genes. Overall, genomic contacts in the nucleus appear to be structured as a network of networks where a set of strongly individual chromosomal units, as envisaged in the 'chromosomal territory' scenario derived from microscopy, interact with each other via on average weaker, yet far from random and functionally important interactions.

  10. Analysis of chromosome conservation in Lemur catta studied by chromosome paints and BAC/PAC probes.

    Science.gov (United States)

    Cardone, Maria Francesca; Ventura, Mario; Tempesta, Sergio; Rocchi, Mariano; Archidiacono, Nicoletta

    2002-12-01

    A panel of human chromosome painting probes and bacterial and P1 artificial chromosome (BAC/PAC) clones were used in fluorescence in situ hybridization (FISH) experiments to investigate the chromosome conservation of the ring-tailed lemur (Lemur catta, LCA) with respect to human. Whole chromosome paints specific for human chromosomes 7, 9, 11, 13, 14, 17, 18, 20, 21, and X were found to identify a single chromosome or an uninterrupted chromosomal region in LCA. A large set of partial chromosome paints and BAC/PAC probes were then used to refine the characterization of the rearrangements differentiating the two karyotypes. The results were also used to reconstruct the ancestral Lemuridae karyotype. Lemur catta, indeed, can be used as an outgroup, allowing symplesiomorphic (ancestral) rearrangements to be distinguished from apomorphic (derived) rearrangements in lemurs. Some LCA chromosomes are difficult to distinguish morphologically. The 'anchorage' of most LCA chromosomes to specific probes will contribute to the standardization of the karyotype of this species.

  11. Insect sex chromosomes. VI. A presumptive hyperactivation of the male X chromosome in Acheta domesticus (L.).

    Science.gov (United States)

    Rao, S R; Ali, S

    1982-01-01

    The functional status of the X chromosome in Acheta domesticus has been analysed at the whole chromosome level on the basis of (1) 3H-thymidine autoradiography, (2) 5-BrdU/AO fluorescence microscopy (3) in vivo 5-BrdU incorporation and (4) 3H-UdR induced aberrations. The rationale of these techniques in relation to the functional aspect of the X chromosome is that the inactive X chromosome would (1) show asynchrony in DNA synthesis, (2) show differential fluorescence, (3) respond differentially to in vivo 5-BrdU treatment and (4) the active X chromosome would show aberrations when treated with 3H-Uridine. From the results, it appears that the X chromosomes in both male (XO) and female (XX) somatic cells of Acheta are euchromatic (active). Further, the single X in the male is transcriptionally as active as the two X chromosomes in the female. In other words, the single X in the male is hyperactive when compared with the single X in the female. From this it is inferred that the male X chromosome is differentially regulated in order to bring about an equalization of it's gene product(s) to that produced by both Xs in the female. Drosophila melanogaster has a comparable system of dosage compensation. Thus, Acheta is yet another insect showing evidence for an X chromosome regulatory mechanism of dosage compensation. Additionally, it is surmised that sex determination in Acheta is based on an autosomes/X chromosome balance mechanism.

  12. Large-scale reconstruction of 3D structures of human chromosomes from chromosomal contact data.

    Science.gov (United States)

    Trieu, Tuan; Cheng, Jianlin

    2014-04-01

    Chromosomes are not positioned randomly within a nucleus, but instead, they adopt preferred spatial conformations to facilitate necessary long-range gene-gene interactions and regulations. Thus, obtaining the 3D shape of chromosomes of a genome is critical for understanding how the genome folds, functions and how its genes interact and are regulated. Here, we describe a method to reconstruct preferred 3D structures of individual chromosomes of the human genome from chromosomal contact data generated by the Hi-C chromosome conformation capturing technique. A novel parameterized objective function was designed for modeling chromosome structures, which was optimized by a gradient descent method to generate chromosomal structural models that could satisfy as many intra-chromosomal contacts as possible. We applied the objective function and the corresponding optimization method to two Hi-C chromosomal data sets of both a healthy and a cancerous human B-cell to construct 3D models of individual chromosomes at resolutions of 1 MB and 200 KB, respectively. The parameters used with the method were calibrated according to an independent fluorescence in situ hybridization experimental data. The structural models generated by our method could satisfy a high percentage of contacts (pairs of loci in interaction) and non-contacts (pairs of loci not in interaction) and were compatible with the known two-compartment organization of human chromatin structures. Furthermore, structural models generated at different resolutions and from randomly permuted data sets were consistent.

  13. Chromosomal aberrations in benign prostatic hyperplasia patients

    Directory of Open Access Journals (Sweden)

    Muammer Altok

    2016-01-01

    Full Text Available Purpose: To investigate the chromosomal changes in patients with benign prostatic hyperplasia (BPH. Materials and Methods: A total of 54 patients diagnosed with clinical BPH underwent transurethral prostate resection to address their primary urological problem. All patients were evaluated by use of a comprehensive medical history and rectal digital examination. The preoperative evaluation also included serum prostate-specific antigen (PSA measurement and ultrasonographic measurement of prostate volume. Prostate cancer was detected in one patient, who was then excluded from the study. We performed conventional cytogenetic analyses of short-term cultures of 53 peripheral blood samples obtained from the BPH patients. Results: The mean (±standard deviation age of the 53 patients was 67.8±9.4 years. The mean PSA value of the patients was 5.8±7.0 ng/mL. The mean prostate volume was 53.6±22.9 mL. Chromosomal abnormalities were noted in 5 of the 53 cases (9.4%. Loss of the Y chromosome was the most frequent chromosomal abnormality and was observed in three patients (5.7%. There was no statistically significant relationship among age, PSA, prostate volume, and chromosomal changes. Conclusions: Loss of the Y chromosome was the main chromosomal abnormality found in our study. However, this coexistence did not reach a significant level. Our study concluded that loss of the Y chromosome cannot be considered relevant for the diagnosis of BPH as it is for prostate cancer. Because BPH usually occurs in aging men, loss of the Y chromosome in BPH patients may instead be related to the aging process.

  14. Chromosomal aberrations in benign prostatic hyperplasia patients

    Science.gov (United States)

    Bağcı, Özkan; Umul, Mehmet; Güneş, Mustafa; Akyüz, Mehmet; Uruç, Fatih; Uz, Efkan; Soyupek, Sedat

    2016-01-01

    Purpose To investigate the chromosomal changes in patients with benign prostatic hyperplasia (BPH). Materials and Methods A total of 54 patients diagnosed with clinical BPH underwent transurethral prostate resection to address their primary urological problem. All patients were evaluated by use of a comprehensive medical history and rectal digital examination. The preoperative evaluation also included serum prostate-specific antigen (PSA) measurement and ultrasonographic measurement of prostate volume. Prostate cancer was detected in one patient, who was then excluded from the study. We performed conventional cytogenetic analyses of short-term cultures of 53 peripheral blood samples obtained from the BPH patients. Results The mean (±standard deviation) age of the 53 patients was 67.8±9.4 years. The mean PSA value of the patients was 5.8±7.0 ng/mL. The mean prostate volume was 53.6±22.9 mL. Chromosomal abnormalities were noted in 5 of the 53 cases (9.4%). Loss of the Y chromosome was the most frequent chromosomal abnormality and was observed in three patients (5.7%). There was no statistically significant relationship among age, PSA, prostate volume, and chromosomal changes. Conclusions Loss of the Y chromosome was the main chromosomal abnormality found in our study. However, this coexistence did not reach a significant level. Our study concluded that loss of the Y chromosome cannot be considered relevant for the diagnosis of BPH as it is for prostate cancer. Because BPH usually occurs in aging men, loss of the Y chromosome in BPH patients may instead be related to the aging process. PMID:26966725

  15. Trends in the evolution of reptilian chromosomes.

    Science.gov (United States)

    Olmo, Ettore

    2008-10-01

    Reptiles are a karyologically heterogeneous group, where some orders and suborders exhibit characteristics similar to those of anamniotes and others share similarities with homeotherms. The class also shows different evolutionary trends, for instance in genome and chromosome size and composition. The turtle DNA base composition is similar to that of mammals, whereas that of lizards and snakes is more similar to that of anamniotes. The major karyological differences between turtles and squamates are the size and composition of the genome and the rate at which chromosomes change. Turtles have larger and more variable genome sizes, and a greater amount of middle repetitive DNA that differs even among related species. In lizards and snakes size of the genome are smaller, single-copy DNA is constant within each suborder, and differences in repetitive DNA involve fractions that become increasingly heterogeneous with widening phylogenetic distance. With regard to variation in karyotype morphology, turtles and crocodiles show low variability in chromosome number, morphology, and G-banding pattern. Greater variability is found among squamates, which have a similar degree of karyotypic change-as do some mammals, such as carnivores and bats-and in which there are also differences among congeneric species. An interesting relationship has been highlighted in the entire class Reptilia between rates of change in chromosomes, number of living species, and rate of extinction. However, different situations obtain in turtles and crocodiles on the one hand, and squamates on the other. In the former, the rate of change in chromosomes is lower and the various evolutionary steps do not seem to have entailed marked chromosomal variation, whereas squamates have a higher rate of change in chromosomes clearly related to the number of living species, and chromosomal variation seems to have played an important role in the evolution of several taxa. The different evolutionary trends in

  16. Progressive segregation of the Escherichia coli chromosome

    DEFF Research Database (Denmark)

    Nielsen, Henrik Jørck; Youngren, Brenda; Hansen, Flemming G.

    2006-01-01

    We have followed the fate of 14 different loci around the Escherichia coli chromosome in living cells at slow growth rate using a highly efficient labelling system and automated measurements. Loci are segregated as they are replicated, but with a marked delay. Most markers segregate in a smooth...... temporal progression from origin to terminus. Thus, the overall pattern is one of continuous segregation during replication and is not consistent with recently published models invoking extensive sister chromosome cohesion followed by simultaneous segregation of the bulk of the chromosome. The terminus...

  17. The Barley Chromosome 5 Linkage Map

    DEFF Research Database (Denmark)

    Jensen, J.; Jørgensen, Jørgen Helms

    1975-01-01

    The distances between nine loci on barley chromosome 5 have been studied in five two-point tests, three three-point tests, and one four-point test. Our previous chromosome 5 linkage map, which contained eleven loci mapped from literature data (Jensen and Jørgensen 1975), is extended with four loci......-position is fixed on the map by a locus (necl), which has a good marker gene located centrally in the linkage group. The positions of the other loci are their distances in centimorgans from the 0-position; loci in the direction of the short chromosome arm are assigned positive values and those...

  18. The terminal DNA structure of mammalian chromosomes.

    OpenAIRE

    McElligott, R; Wellinger, R J

    1997-01-01

    In virtually all eukaryotic organisms, telomeric DNA is composed of a variable number of short direct repeats. While the primary sequence of telomeric repeats has been determined for a great variety of species, the actual physical DNA structure at the ends of a bona fide metazoan chromosome with a centromere is unknown. It is shown here that an overhang of the strand forming the 3' ends of the chromosomes, the G-rich strand, is found at mammalian chromosome ends. Moreover, on at least some te...

  19. Chromosomal abnormalities in patients with sperm disorders

    Directory of Open Access Journals (Sweden)

    L. Y. Pylyp

    2013-02-01

    Full Text Available Chromosomal abnormalities are among the most common genetic causes of spermatogenic disruptions. Carriers of chromosomal abnormalities are at increased risk of infertility, miscarriage or birth of a child with unbalanced karyotype due to the production of unbalanced gametes. The natural selection against chromosomally abnormal sperm usually prevents fertilization with sperm barring in cases of serious chromosomal abnormalities. However, assisted reproductive technologies in general and intracytoplasmic sperm injection in particular, enable the transmission of chromosomal abnormalities to the progeny. Therefore, cytogenetic studies are important in patients with male factor infertility before assisted reproduction treatment. The purpose of the current study was to investigate the types and frequencies of chromosomal abnormalities in 724 patients with infertility and to estimate the risk of chromosomal abnormalities detection in subgroups of patients depending on the severity of spermatogenic disruption, aiming at identifying groups of patients in need of cytogenetic studies. Karyotype analysis was performed in 724 blood samples of men attending infertility clinic. Chromosomal preparation was performed by standard techniques. At least 20 GTG-banded metaphase plates with the resolution from 450 to 750 bands per haploid set were analysed in each case. When chromosomal mosaicism was suspected, this number was increased to 50. Abnormal karyotypes were observed in 48 (6.6% patients, including 67% of autosomal abnormalities and 33% of gonosomal abnormalities. Autosomal abnormalities were represented by structural rearrangements. Reciprocal translocations were the most common type of structural chromosomal abnormalities in the studied group, detected with the frequency of 2.6% (n = 19, followed by Robertsonian translocation, observed with the frequency of 1.2% (n = 9. The frequency of inversions was 0.6% (n = 4. Gonosomal abnormalities included 14 cases

  20. Mayans: a Y chromosome perspective

    Science.gov (United States)

    Perez-Benedico, David; La Salvia, Joel; Zeng, Zhaoshu; Herrera, Giselle A; Garcia-Bertrand, Ralph; Herrera, Rene J

    2016-01-01

    In spite of the wealth of available cultural and archeological information as well as general interest in the Mayans, little is known about their genetics. In this study, for the first time, we attempt to alleviate this lacuna of knowledge by comprehensively investigating the Y chromosome composition of contemporary Mayan populations throughout their domain. To accomplish this, five geographically targeted and ethnically distinct Mayan populations are investigated using Y-SNP and Y-STR markers. Findings: overall, the Mayan populations as a group are highly homogeneous, basically made up of only two autochthonous haplogroups, Q1a2a1a1*-M3 and Q1a2a1*-L54. Although the Y-STR data illustrates diversity, this diversity, for the most part, is uniformly distributed among geographically distant Mayan populations. Similar haplotypes among populations, abundance of singletons and absence of population partitioning within networks among Mayan populations suggest recent population expansion and substantial gene flow within the Mayan dominion, possibly due to the development of agriculture, the establishment of interacting City–State systems and commerce. PMID:26956252

  1. Y chromosome haplogroups in autistic subjects : Y chromosome in autistic subjects

    OpenAIRE

    Jamain, Stéphane; Quach, Hélène; Quintana-Murci, Luis; Betancur, Catalina; Philippe, Anne; Gillberg, Christopher; Sponheim, Eili; Skjeldal, Ola,; Fellous, Marc; Leboyer, Marion; Bourgeron, Thomas

    2002-01-01

    The male to female ratio in autism is 4:1 in the global autistic population, but increases to 23:1 in autistic subjects without physical or brain abnormalities. Despite this well-recognised gender difference, male predisposition to autistic disorder remains unexplained and the role of sex chromosomes is still debated. Numerical and structural abnormalities of the sex chromosomes are among the most frequently reported chromosomal disorders associated with autism. However, genome scans have fai...

  2. The Chromosomal Passenger Complex Is Required for Meiotic Acentrosomal Spindle Assembly and Chromosome Biorientation

    OpenAIRE

    Radford, Sarah J.; Jang, Janet K.; McKim, Kim S.

    2012-01-01

    DURING meiosis in the females of many species, spindle assembly occurs in the absence of the microtubule-organizing centers called centrosomes. In the absence of centrosomes, the nature of the chromosome-based signal that recruits microtubules to promote spindle assembly as well as how spindle bipolarity is established and the chromosomes orient correctly toward the poles is not known. To address these questions, we focused on the chromosomal passenger complex (CPC). We have found that the CP...

  3. Chromosome characterization using single fluorescent dye

    Energy Technology Data Exchange (ETDEWEB)

    Crissman, Harry A. (Los Alamos, NM); Hirons, Gregory T. (Irvine, CA)

    1995-01-01

    Chromosomes are characterized by fluorescent emissions from a single fluorescent dye that is excited over two different wavelengths. A mixture containing chromosomes is stained with a single dye selected from the group consisting of TOTO and YOYO and the stained chromosomes are placed in a flow cytometer. The fluorescent dye is excited sequentially by a first light having a wavelength in the ultraviolet range to excite the TOTO or YOYO to fluoresce at a first intensity and by a second light having a wavelength effective to excite the TOTO or YOYO dye to fluoresce at a second intensity. Specific chromosomes may be identified and sorted by intensity relationships between the first and second fluorescence emissions.

  4. Genetics Home Reference: Y chromosome infertility

    Science.gov (United States)

    ... chromosomal abnormalities in 2078 infertile couples referred for assisted reproductive techniques. Hum Reprod. 2005 Feb;20(2):437-42. ... Yq microdeletions in infertile italian couples referred for assisted reproductive technique. Sex Dev. 2007;1(6):347-52. doi: ...

  5. Chromosomal contact permits transcription between coregulated genes

    CSIR Research Space (South Africa)

    Fanucchi, Stephanie

    2013-10-01

    Full Text Available . To ask whether chromosomal contacts are required for cotranscription in multigene complexes, we devised a strategy using TALENs to cleave and disrupt gene loops in a well-characterized multigene complex. Monitoring this disruption using RNA FISH...

  6. Chromosomal aberrations in uranium and coal miners

    Energy Technology Data Exchange (ETDEWEB)

    Wolf, G.; Arndt, D.; Kotschy-Lang, N.; Obe, G. [Robert Koch Inst., Berlin (Germany)

    2004-02-01

    Peripheral lymphocytes from 66 Wismut uranium miners (WUM) and 29 Ruhr coal miners (RGM) were cultured and analysed for structural chromosomal aberrations in Giemsa-stained M1 metaphases. Cytogenetic data from 23 male white-collar workers from public services were used as a historical control group. The frequencies of chromosomal aberrations and sister chromatid exchanges in WUM and RCM were quite similar. Compared with public services workers, WUM and RCM had significantly higher frequencies of chromosomal aberrations. It is concluded that chromosomal aberrations in WUM are not induced by radioactive particles inhaled during underground mining but as in RCM rather result from factors such as age, lifestyle, illnesses, medications and diagnostic irradiations.

  7. IAPT/IOPB chromosome data 25 - Asteraceae

    Czech Academy of Sciences Publication Activity Database

    Krahulcová, Anna

    2017-01-01

    Roč. 66, č. 5 (2017), s. 1249-1249 ISSN 0040-0262 Institutional support: RVO:67985939 Keywords : chromosome numbers * DNA ploidy level * anginosperms Subject RIV: EF - Botanics Impact factor: 2.447, year: 2016

  8. Genetics Home Reference: ring chromosome 20 syndrome

    Science.gov (United States)

    ... F, Verardi R, Grande G, Stabile M. Electroclinical evolution in ring chromosome 20 epilepsy syndrome: a case ... care or advice. Users with questions about a personal health condition should consult with a qualified healthcare ...

  9. Temporal genomic evolution of bird sex chromosomes

    DEFF Research Database (Denmark)

    Wang, Zongji; Zhang, Jilin; Yang, Wei

    2014-01-01

    driving forces of Z chromosome evolution, we analyze here 45 newly available bird genomes and four species' transcriptomes, over their course of recombination loss between the sex chromosomes. RESULTS: We show Z chromosomes in general have a significantly higher substitution rate in introns and synonymous...... protein-coding sites than autosomes, driven by the male-to-female mutation bias ('male-driven evolution' effect). Our genome-wide estimate reveals that the degree of such a bias ranges from 1.6 to 3.8 among different species. G + C content of third codon positions exhibits the same trend of gradual...... ('fast-Z' evolution). And species with a lower level of intronic heterozygosities tend to evolve even faster on the Z chromosome. Further analysis of fast-evolving genes' enriched functional categories and sex-biased expression patterns support that, fast-Z evolution in birds is mainly driven by genetic...

  10. Complement activation in chromosome 13 dementias

    DEFF Research Database (Denmark)

    Rostagno, A.; Revesz, T.; Lashley, T.

    2002-01-01

    Chromosome 13 dementias, familial British dementia (FBD) and familial Danish dementia (FDD), are associated with neurodegeneration and cerebrovascular amyloidosis, with striking neuropathological similarities to Alzheimer's disease (AD). Despite the structural differences among the amyloid subunits...

  11. Non-disjunction of chromosome 13

    DEFF Research Database (Denmark)

    Bugge, Merete; Collins, Andrew; Hertz, Jens Michael

    2007-01-01

    We performed a molecular study with 21 microsatellites on a sample of 82 trisomy 13 conceptuses, the largest number of cases studied to date. The parental origin was determined in every case and in 89% the extra chromosome 13 was of maternal origin with an almost equal number of maternal MI and MII...... recombination in both maternal MI and MII errors and the former is associated with a significant number of tetrads (33%) that are nullichiasmate, which do not appear to be a feature of normal chromosome 13 meiosis. This study supports the evidence for subtle chromosome-specific influences on the mechanisms...... that determine non-disjunction of human chromosomes, consistent with the diversity of findings for other trisomies....

  12. Meiosis I: When Chromosomes Undergo Extreme Makeover

    Science.gov (United States)

    Miller, Matthew P.; Amon, Angelika; Ünal, Elçin

    2013-01-01

    The ultimate success of cell division relies on the accurate partitioning of the genetic material. Errors in this process occur in nearly all tumors and are the leading cause of miscarriages and congenital birth defects in humans. Two cell divisions, mitosis and meiosis, use common as well as unique mechanisms to ensure faithful chromosome segregation. In mitosis, alternating rounds of DNA replication and chromosome segregation preserves the chromosome complement of the progenitor cell. In contrast, during meiosis two consecutive rounds of nuclear division, meiosis I and meiosis II, follow a single round of DNA replication to reduce the chromosome complement by half. Meiosis likely evolved through changes to the mitotic cell division program. This review will focus on the recent findings describing the modifications that transform mitosis into meiosis. PMID:23916768

  13. Demasculinization of the Anopheles gambiae X chromosome

    Directory of Open Access Journals (Sweden)

    Magnusson Kalle

    2012-05-01

    Full Text Available Abstract Background In a number of organisms sex-biased genes are non-randomly distributed between autosomes and the shared sex chromosome X (or Z. Studies on Anopheles gambiae have produced conflicting results regarding the underrepresentation of male-biased genes on the X chromosome and it is unclear to what extent sexual antagonism, dosage compensation or X-inactivation in the male germline, the evolutionary forces that have been suggested to affect the chromosomal distribution of sex-biased genes, are operational in Anopheles. Results We performed a meta-analysis of sex-biased gene expression in Anopheles gambiae which provides evidence for a general underrepresentation of male-biased genes on the X-chromosome that increased in significance with the observed degree of sex-bias. A phylogenomic comparison between Drosophila melanogaster, Aedes aegypti and Culex quinquefasciatus also indicates that the Anopheles X chromosome strongly disfavours the evolutionary conservation of male-biased expression and that novel male-biased genes are more likely to arise on autosomes. Finally, we demonstrate experimentally that transgenes situated on the Anopheles gambiae X chromosome are transcriptionally silenced in the male germline. Conclusion The data presented here support the hypothesis that the observed demasculinization of the Anopheles X chromosome is driven by X-chromosome inactivation in the male germline and by sexual antagonism. The demasculinization appears to be the consequence of a loss of male-biased expression, rather than a failure in the establishment or the extinction of male-biased genes.

  14. Chromosomal abnormalities in child psychiatric patients.

    OpenAIRE

    Hong, K. E.; Kim, J. H.; Moon, S. Y.; Oh, S. K.

    1999-01-01

    To determine the frequency of chromosomal abnormalities in a child psychiatric population, and to evaluate possible associations between types of abnormalities and patient's clinical characteristics, cytogenetic examination was performed on 604 patients. Demographic data, reasons for karyotyping, clinical signs, and other patient characteristics were assessed and correlated with the results from karyotyping. Chromosomal abnormalities were found in 69 patients (11.3%); these were structural in...

  15. Chromosomal profile of indigenous pig (Sus scrofa

    Directory of Open Access Journals (Sweden)

    P. Guru Vishnu

    2015-02-01

    Full Text Available Aim: The objective of this study was to investigate the chromosomal profile of indigenous pigs by computing morphometric measurements. Materials and Methods: A cytogenetic study was carried out in 60 indigenous pigs to analyze the chromosomal profile by employing the short term peripheral blood lymphocyte culture technique. Results: The modal chromosome number (2n in indigenous pigs was found to be 38 and a fundamental number of 64 as in the exotic. First chromosome was the longest pair, and thirteenth pair was the second largest while Y-chromosome was the smallest in the karyotype of the pig. The mean relative length, arm ratio, centromeric indices and morphological indices of chromosomes varied from 1.99±0.01 to 11.23±0.09, 1.04±0.05 to 2.95±0.02, 0.51±0.14 to 0.75±0.09 and 2.08±0.07 to 8.08±0.15%, respectively in indigenous pigs. Sex had no significant effect (p>0.05 on all the morphometric measurements studied. Conclusion: The present study revealed that among autosomes first five pairs were sub metacentric, next two pairs were sub telocentric (6-7, subsequent five pairs were metacentric (8-12 and remaining six pairs were telocentric (13-18, while both allosomes were metacentric. The chromosomal number, morphology and various morphometric measurements of the chromosomes of the indigenous pigs were almost similar to those established breeds reported in the literature.

  16. Chromosomal evolution in the plant family Solanaceae.

    Science.gov (United States)

    Wu, Feinan; Tanksley, Steven D

    2010-03-17

    Over the past decades, extensive comparative mapping research has been performed in the plant family Solanaceae. The recent identification of a large set of single-copy conserved orthologous (COSII) markers has greatly accelerated comparative mapping studies among major solanaceous species including tomato, potato, eggplant, pepper and diploid Nicotiana species (as well as tetraploid tobacco). The large amount of comparative data now available for these species provides the opportunity to describe the overall patterns of chromosomal evolution in this important plant family. The results of this investigation are described herein. We combined data from multiple COSII studies, and other comparative mapping studies performed in tomato, potato, eggplant, pepper and diploid Nicotiana species, to deduce the features and outcomes of chromosomal evolution in the Solanaceae over the past 30 million years. This includes estimating the rates and timing of chromosomal changes (inversions and translocations) as well as deducing the age of ancestral progenitor species and predicting their genome configurations. The Solanaceae has experienced chromosomal changes at a modest rate compared with other families and the rates are likely conserved across different lineages of the family. Chromosomal inversions occur at a consistently higher rate than do translocations. Further, we find evidences for non-random positioning of the chromosomal rearrangement breakpoints. This finding is consistent with the similar finding in mammals, where hot spots for chromosomal breakages have apparently played a significant role in shaping genome evolution. Finally, by utilizing multiple genome comparisons we were able to reconstruct the most likely genome configuration for a number of now-extinct progenitor species that gave rise to the extant solanaceous species used in this research. The results from this study provide the first broad overview of chromosomal evolution in the family Solanaceae, and

  17. Female meiotic sex chromosome inactivation in chicken.

    Directory of Open Access Journals (Sweden)

    Sam Schoenmakers

    2009-05-01

    Full Text Available During meiotic prophase in male mammals, the heterologous X and Y chromosomes remain largely unsynapsed, and meiotic sex chromosome inactivation (MSCI leads to formation of the transcriptionally silenced XY body. In birds, the heterogametic sex is female, carrying Z and W chromosomes (ZW, whereas males have the homogametic ZZ constitution. During chicken oogenesis, the heterologous ZW pair reaches a state of complete heterologous synapsis, and this might enable maintenance of transcription of Z- and W chromosomal genes during meiotic prophase. Herein, we show that the ZW pair is transiently silenced, from early pachytene to early diplotene using immunocytochemistry and gene expression analyses. We propose that ZW inactivation is most likely achieved via spreading of heterochromatin from the W on the Z chromosome. Also, persistent meiotic DNA double-strand breaks (DSBs may contribute to silencing of Z. Surprisingly, gammaH2AX, a marker of DSBs, and also the earliest histone modification that is associated with XY body formation in mammalian and marsupial spermatocytes, does not cover the ZW during the synapsed stage. However, when the ZW pair starts to desynapse, a second wave of gammaH2AX accumulates on the unsynapsed regions of Z, which also show a reappearance of the DSB repair protein RAD51. This indicates that repair of meiotic DSBs on the heterologous part of Z is postponed until late pachytene/diplotene, possibly to avoid recombination with regions on the heterologously synapsed W chromosome. Two days after entering diplotene, the Z looses gammaH2AX and shows reactivation. This is the first report of meiotic sex chromosome inactivation in a species with female heterogamety, providing evidence that this mechanism is not specific to spermatogenesis. It also indicates the presence of an evolutionary force that drives meiotic sex chromosome inactivation independent of the final achievement of synapsis.

  18. Chromosome 11q13 deletion syndrome

    OpenAIRE

    Kim, Yu-Seon; Kim, Gun-Ha; Byeon, Jung Hye; Eun, So-Hee; Eun, Baik-Lin

    2016-01-01

    Chromosome 11q13 deletion syndrome has been previously reported as either otodental syndrome or oculo-oto-dental syndrome. The otodental syndrome is characterized by dental abnormalities and high-frequency sensorineural hearing loss, and by ocular coloboma in some cases. The underlying genetic defect causing otodental syndrome is a hemizygous microdeletion involving the FGF3 gene on chromosome 11q13.3. Recently, a new form of severe deafness, microtia (small ear) and small teeth, without the ...

  19. Plasmid and chromosome segregation in prokaryotes

    DEFF Research Database (Denmark)

    Møller-Jensen, Jakob; Bugge Jensen, Rasmus; Gerdes, Kenn

    2000-01-01

    Recent major advances in the understanding of prokaryotic DNA segregation have been achieved by using fluorescence microscopy to visualize the localization of cellular components. Plasmids and bacterial chromosomes are partitioned in a highly dynamic fashion, suggesting the presence of a mitotic......-like apparatus in prokaryotes. The identification of chromosomal homologues of the well-characterized plasmid partitioning genes indicates that there could be a general mechanism of bacterial DNA partitioning. Udgivelsesdato: July 1...

  20. Abnormal sex chromosome constitution and longitudinal growth

    DEFF Research Database (Denmark)

    Aksglaede, Lise; Skakkebaek, Niels E; Juul, Anders

    2008-01-01

    Growth is a highly complex process regulated by the interaction between sex steroids and the GH IGF-axis. However, other factors such as sex chromosome-related genes play independent roles.......Growth is a highly complex process regulated by the interaction between sex steroids and the GH IGF-axis. However, other factors such as sex chromosome-related genes play independent roles....

  1. Sequence conservation on the Y chromosome

    Energy Technology Data Exchange (ETDEWEB)

    Gibson, L.H.; Yang-Feng, L. [Yale Univ. School of Medicine, New Haven, CT (United States); Lau, C. [Univ. of California, San Francisco, CA (United States)

    1994-09-01

    The Y chromosome is present in all mammals and is considered to be essential to sex determination. Despite intense genomic research, only a few genes have been identified and mapped to this chromosome in humans. Several of them, such as SRY and ZFY, have been demonstrated to be conserved and Y-located in other mammals. In order to address the issue of sequence conservation on the Y chromosome, we performed fluorescence in situ hybridization (FISH) with DNA from a human Y cosmid library as a probe to study the Y chromosomes from other mammalian species. Total DNA from 3,000-4,500 cosmid pools were labeled with biotinylated-dUTP and hybridized to metaphase chromosomes. For human and primate preparations, human cot1 DNA was included in the hybridization mixture to suppress the hybridization from repeat sequences. FISH signals were detected on the Y chromosomes of human, gorilla, orangutan and baboon (Old World monkey) and were absent on those of squirrel monkey (New World monkey), Indian munjac, wood lemming, Chinese hamster, rat and mouse. Since sequence analysis suggested that specific genes, e.g. SRY and ZFY, are conserved between these two groups, the lack of detectable hybridization in the latter group implies either that conservation of the human Y sequences is limited to the Y chromosomes of the great apes and Old World monkeys, or that the size of the syntenic segment is too small to be detected under the resolution of FISH, or that homologeous sequences have undergone considerable divergence. Further studies with reduced hybridization stringency are currently being conducted. Our results provide some clues as to Y-sequence conservation across species and demonstrate the limitations of FISH across species with total DNA sequences from a particular chromosome.

  2. Chromosomal organization and segregation in Pseudomonas aeruginosa.

    Directory of Open Access Journals (Sweden)

    Isabelle Vallet-Gely

    2013-05-01

    Full Text Available The study of chromosomal organization and segregation in a handful of bacteria has revealed surprising variety in the mechanisms mediating such fundamental processes. In this study, we further emphasized this diversity by revealing an original organization of the Pseudomonas aeruginosa chromosome. We analyzed the localization of 20 chromosomal markers and several components of the replication machinery in this important opportunistic γ-proteobacteria pathogen. This technique allowed us to show that the 6.3 Mb unique circular chromosome of P. aeruginosa is globally oriented from the old pole of the cell to the division plane/new pole along the oriC-dif axis. The replication machinery is positioned at mid-cell, and the chromosomal loci from oriC to dif are moved sequentially to mid-cell prior to replication. The two chromosomal copies are subsequently segregated at their final subcellular destination in the two halves of the cell. We identified two regions in which markers localize at similar positions, suggesting a bias in the distribution of chromosomal regions in the cell. The first region encompasses 1.4 Mb surrounding oriC, where loci are positioned around the 0.2/0.8 relative cell length upon segregation. The second region contains at least 800 kb surrounding dif, where loci show an extensive colocalization step following replication. We also showed that disrupting the ParABS system is very detrimental in P. aeruginosa. Possible mechanisms responsible for the coordinated chromosomal segregation process and for the presence of large distinctive regions are discussed.

  3. Chromosomal Abnormality in Men with Impaired Spermatogenesis

    OpenAIRE

    Dana Mierla; Dumitru Jardan; Veronica Stoian

    2014-01-01

    Background: Chromosomal abnormalities and Y chromosome microdeletions are regarded as two most frequent genetic causes associated with failure of spermatogenesis in the Caucasian population. Materials and Methods: To investigate the distribution of genetic defects in the Romanian population with azoospermia or severe oligozoospermia, karyotype analysis by G-banding was carried out in 850 idiopathic infertile men and in 49 fertile men with one or more children. Screening for microdeletions in ...

  4. Modelling chromosomal aberration induction by ionising radiation: The influence of interphase chromosome architecture

    Science.gov (United States)

    Ottolenghi, A.; Ballarini, F.; Biaggi, M.

    Several advances have been achieved in the knowledge of nuclear architecture and functions during the last decade, thus allowing the identification of interphase chromosome territories and sub-chromosomal domains (e.g. arm and band domains). This is an important step in the study of radiation-induced chromosome aberrations; indeed, the coupling between track-structure simulations and reliable descriptions of the geometrical properties of the target is one of the main tasks in modelling aberration induction by radiation, since it allows one to clarify the role of the initial positioning of two DNA lesions in determining their interaction probability. In the present paper, the main recent findings on nuclear and chromosomal architecture are summarised. A few examples of models based on different descriptions of interphase chromosome organisation (random-walk models, domain models and static models) are presented, focussing on how the approach adopted in modelling the target nuclei and chromosomes can influence the simulation of chromosomal aberration yields. Each model is discussed by taking into account available experimental data on chromosome aberration induction and/or interphase chromatin organisation. Preliminary results from a mechanistic model based on a coupling between radiation track-structure features and explicitly-modelled, non-overlapping chromosome territories are presented.

  5. Application of chromosomal microdissection, polymerase chain reaction (PCR), and reverse chromosome painting in prenatal diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Wang, N.; Xu, J.; Cedrone, E. [Univ. of Rochester School of Medicine, Rochester, NY (United States)

    1994-09-01

    De novo marker chromosomes have been found in about 0.04% of amniotic fluid cultures. The origin of these marker chromosomes is difficult to identify by routine chromosome banding analysis. In the present study, we applied microdissection, PCR, and reverse chromosome painting to two amniotic fluid cases with a karyotype of 47,XX,+mar, and 47,XX,+?i(9p), respectively. Fluorescence in situ hybridization of the biotin-labeled DNA probe generated from 5 copies of the dissected marker chromosomes was applied to the normal metaphase spreads and revealed that the marker originated from the p arm of chromosomes 14 and 22, while the ?i(9p) was actually i(4p). Reverse painting of the same probe to the metaphase spreads of the patients completely painted the marker chromosomes in question, which confirms the accuracy of the analysis. Our study provides an example of the application of chromosome microdissection and molecular cytogenetics in prenatal diagnosis for the identification of marker chromosomes unidentifiable by routine analysis.

  6. Homomorphic sex chromosomes and the intriguing Y chromosome of Ctenomys rodent species (Rodentia, Ctenomyidae).

    Science.gov (United States)

    Suárez-Villota, Elkin Y; Pansonato-Alves, José C; Foresti, Fausto; Gallardo, Milton H

    2014-01-01

    Unlike the X chromosome, the mammalian Y chromosome undergoes evolutionary decay resulting in small size. This sex chromosomal heteromorphism, observed in most species of the fossorial rodent Ctenomys, contrasts with the medium-sized, homomorphic acrocentric sex chromosomes of closely related C. maulinus and C. sp. To characterize the sequence composition of these chromosomes, fluorescent banding, self-genomic in situ hybridization, and fluorescent in situ hybridization with an X painting probe were performed on mitotic and meiotic plates. High molecular homology between the sex chromosomes was detected on mitotic material as well as on meiotic plates immunodetected with anti-SYCP3 and anti-γH2AX. The Y chromosome is euchromatic, poor in repetitive sequences and differs from the X by the loss of a block of pericentromeric chromatin. Inferred from the G-banding pattern, an inversion and the concomitant prevention of recombination in a large asynaptic region seems to be crucial for meiotic X chromosome inactivation. These peculiar findings together with the homomorphism of Ctenomys sex chromosomes are discussed in the light of the regular purge that counteracts Muller's ratchet and the probable mechanisms accounting for their origin and molecular homology. © 2014 S. Karger AG, Basel.

  7. Paternal isodisomy of chromosome 6 in association with a maternal supernumerary marker chromosome (6)

    Energy Technology Data Exchange (ETDEWEB)

    James, R.S.; Crolla, J.A.; Sitch, F.L. [Salisbury District Hospital, Wiltshire (United Kingdom)] [and others

    1994-09-01

    Uniparental disomy may arise by a number of different mechanisms of aneuploidy correction. A population that has been identified as being at increased risk of aneuploidy are those individuals bearing supernumerary marker chromosomes (SMCs). There have been a number of cases reported of trisomy 21 in association with bi-satellited marker chromosomes have described two individuals with small inv dup (15) markers. One had paternal isodisomy of chromosome 15 and Angelman syndrome. The other had maternal heterodisomy (15) and Prader-Willi syndrome. At the Wessex Regional Genetics Laboratory we have conducted a search for uniparental disomy of the normal homologues of the chromosomes from which SMCs originated. Our study population consists of 39 probands with SMCs originating from a number of different autosomes, including 17 with SMCs of chromosome 15 origin. Using PCR amplification of microsatellite repeat sequences located distal to the regions included in the SMCs we have determined the parental origin of the two normal homologues in each case. We have identified paternal isodisomy of chromosome 6 in a female child with a supernumerary marker ring chromosome 6 in approximately 70% of peripheral blood lymphocytes. The marker was found to be of maternal origin. This is the second case of paternal isodisomy of chromosome 6 to be reported, and the first in association with a SMC resulting in a partial trisomy for a portion of the short arm of chromosome 6. In spite of this, the patient appears to be functioning appropriately for her age.

  8. The hierarchically organized splitting of chromosomal bands for all human chromosomes

    Directory of Open Access Journals (Sweden)

    Liehr Thomas

    2009-01-01

    Full Text Available Abstract Background Chromosome banding is widely used in cytogenetics. However, the biological nature of hierarchically organized splitting of chromosomal bands of human chromosomes is an enigma and has not been, as yet, studied. Results Here we present for the first time the hierarchically organized splitting of chromosomal bands in their sub-bands for all human chromosomes. To do this, array-proved multicolor banding (aMCB probe-sets for all human chromosomes were applied to normal metaphase spreads of three different G-band levels. We confirmed for all chromosomes to be a general principle that only Giemsa-dark bands split into dark and light sub-bands, as we demonstrated previously by chromosome stretching. Thus, the biological band splitting is in > 50% of the sub-bands different than implemented by the ISCN nomenclature suggesting also a splitting of G-light bands. Locus-specific probes exemplary confirmed the results of MCB. Conclusion Overall, the present study enables a better understanding of chromosome architecture. The observed difference of biological and ISCN band-splitting may be an explanation why mapping data from human genome project do not always fit the cytogenetic mapping.

  9. Whole chromosome gain does not in itself confer cancer-like chromosomal instability.

    Science.gov (United States)

    Valind, Anders; Jin, Yuesheng; Baldetorp, Bo; Gisselsson, David

    2013-12-24

    Constitutional aneuploidy is typically caused by a single-event meiotic or early mitotic error. In contrast, somatic aneuploidy, found mainly in neoplastic tissue, is attributed to continuous chromosomal instability. More debated as a cause of aneuploidy is aneuploidy itself; that is, whether aneuploidy per se causes chromosomal instability, for example, in patients with inborn aneuploidy. We have addressed this issue by quantifying the level of somatic mosaicism, a proxy marker of chromosomal instability, in patients with constitutional aneuploidy by precise background-filtered dual-color FISH. In contrast to previous studies that used less precise methods, we find that constitutional trisomy, even for large chromosomes that are often trisomic in cancer, does not confer a significantly elevated rate of somatic chromosomal mosaicism in individual cases. Constitutional triploidy was associated with an increased level of somatic mosaicism, but this consisted mostly of reversion from trisomy to disomy and did not correspond to a proportionally elevated level of chromosome mis-segregation in triploids, indicating that the observed mosaicism resulted from a specific accumulation of cells with a hypotriploid chromosome number. In no case did the rate of somatic mosaicism in constitutional aneuploidy exceed that of "chromosomally stable" cancer cells. Our findings show that even though constitutional aneuploidy was in some cases associated with low-level somatic mosaicism, it was insufficient to generate the cancer-like levels expected if aneuploidy single-handedly triggered cancer-like chromosomal instability.

  10. Neo-sex chromosomes of Ronderosia bergi: insight into the evolution of sex chromosomes in grasshoppers.

    Science.gov (United States)

    Palacios-Gimenez, O M; Marti, D A; Cabral-de-Mello, D C

    2015-09-01

    Sex chromosomes have evolved many times from morphologically identical autosome pairs, most often presenting several recombination suppression events, followed by accumulation of repetitive DNA sequences. In Orthoptera, most species have an X0♂ sex chromosome system. However, in the subfamily Melanoplinae, derived variants of neo-sex chromosomes (neo-XY♂ or neo-X1X2Y♂) emerged several times. Here, we examined the differentiation of neo-sex chromosomes in a Melanoplinae species with a neo-XY♂/XX♀ system, Ronderosia bergi, using several approaches: (i) classical cytogenetic analysis, (ii) mapping via fluorescent in situ hybridization of some selected repetitive DNA sequences and microdissected sex chromosomes, and (iii) immunolocalization of distinct histone modifications. The microdissected sex chromosomes were also used as sources for Polymerase chain reaction (PCR) amplification of RNA-coding multigene families, to study variants related to the sex chromosomes. Our data suggest that the R. bergi neo-Y has become differentiated after its formation by a Robertsonian translocation and inversions, and has accumulated repetitive DNA sequences. Interestingly, the ex autosomes incorporated into the neo-sex chromosomes retain some autosomal post-translational histone modifications, at least in metaphase I, suggesting that the establishment of functional modifications in neo-sex chromosomes is slower than their sequence differentiation.

  11. Interphase Chromosome Profiling: A Method for Conventional Banded Chromosome Analysis Using Interphase Nuclei.

    Science.gov (United States)

    Babu, Ramesh; Van Dyke, Daniel L; Dev, Vaithilingam G; Koduru, Prasad; Rao, Nagesh; Mitter, Navnit S; Liu, Mingya; Fuentes, Ernesto; Fuentes, Sarah; Papa, Stephen

    2017-10-05

    - Chromosome analysis on bone marrow or peripheral blood samples fails in a small proportion of attempts. A method that is more reliable, with similar or better resolution, would be a welcome addition to the armamentarium of the cytogenetics laboratory. - To develop a method similar to banded metaphase chromosome analysis that relies only on interphase nuclei. - To label multiple targets in an equidistant fashion along the entire length of each chromosome, including landmark subtelomere and centromere regions. Each label so generated by using cloned bacterial artificial chromosome probes is molecularly distinct with unique spectral characteristics, so the number and position of the labels can be tracked to identify chromosome abnormalities. - Interphase chromosome profiling (ICP) demonstrated results similar to conventional chromosome analysis and fluorescence in situ hybridization in 55 previously studied cases and obtained useful ICP chromosome analysis results on another 29 cases in which conventional methods failed. - ICP is a new and powerful method to karyotype peripheral blood and bone marrow aspirate preparations without reliance on metaphase chromosome preparations. It will be of particular value for cases with a failed conventional analysis or when a fast turnaround time is required.

  12. Coexistence of inverted Y, chromosome 15p+ and abnormal phenotype.

    Science.gov (United States)

    Acar, H; Cora, T; Erkul, I

    1999-01-01

    In this study, we report conventional and molecular cytogenetic studies in a patient with multiple anomalies who is a carrier of a pericentric inversion on chromosome Y and a chromosome 15p+. His parents were phenotypically normal. The father is a carrier of a pericentric inversion of chromosome Y, and the mother carries a large chromosome 15p+ variant. The inverted Y chromosome was demonstrated by GTG- and CBG-banding, and DAPI-staining. The presence of extra chromosomal material on the chromosome 15p, that was C-band and DAPI positive, was demonstrated by trypsin G-banding. This suggests that the extra chromosomal material contained repetitive DNA sequences. NOR-staining indicated the presence a nuclear organizer region at the junction of the chromosome 15p+ material. Fluorescence in situ hybridization (FISH), with chromosome X and Y painting probes, alpha- and classic-satellite probes specific for chromosome Y, alpha- and beta-satellite III probes for chromosome 15 were used to elucidate the nature of both the inverted Y chromosome and chromosome 15p+. The result with chromosome X and Y painting probes, alpha-satellite, classic-satellite, and DYS59 probes specific for chromosome Y revealed the rearrangement of the Y chromosome was an inv(Y)(p11.2q11.22 or q11.23). FISH with alpha-satellite and beta-satellite III probes for chromosome 15 demonstrated that the extra chromosomal material on the chromosome 15 probably represents beta-satellite III sequences. The possible roles of the simultaneous occurrence of an inverted Y and the amplified DNA sequence on chromosome 15p in the abnormal phenotype of the proband are discussed.

  13. Centromeric banding pattern of mitotic chromosomes in Vigna vexillata

    African Journals Online (AJOL)

    Vigna vexillata chromosome characterization was carried out using the Leishman C- banding technique. The results showed that the chromosomes mostly exhibited bands at both the centromeric and telomeric regions. These bands will serve, as a valuable marker for the identification of the chromosomes. Chromosomes 2 ...

  14. Discovery of Supernumerary B Chromosomes in Drosophila melanogaster

    Science.gov (United States)

    Bauerly, Elisabeth; Hughes, Stacie E.; Vietti, Dana R.; Miller, Danny E.; McDowell, William; Hawley, R. Scott

    2014-01-01

    B chromosomes are small, heterochromatic chromosomes that are transmitted in a non-Mendelian manner. We have identified a stock of Drosophila melanogaster that recently (within the last decade) acquired an average of 10 B chromosomes per fly. These B chromosomes are transmitted by both males and females and can be maintained for multiple generations in a wild-type genetic background despite the fact that they cause high levels of 4th chromosome meiotic nondisjunction in females. Most curiously, these B chromosomes are mitotically unstable, suggesting either the absence of critical chromosomal sites or the inability of the meiotic or mitotic systems to cope with many additional chromosomes. These B chromosomes also contain centromeres and are primarily composed of the heterochromatic AATAT satellite sequence. Although the AATAT sequence comprises the majority of the 4th chromosome heterochromatin, the B chromosomes lack most, if not all, 4th chromosome euchromatin. Presumably as a consequence of their heterochromatic content, these B chromosomes significantly modify position-effect variegation in two separate reporter systems, acting as enhancers of variegation in one case and suppressors in the other. The identification of B chromosomes in a genetically tractable organism like D. melanogaster will facilitate studies of chromosome evolution and the analysis of the mechanisms by which meiotic and mitotic processes cope with additional chromosomes. PMID:24478336

  15. Label Free Chromosome Translocation Detection with Silicon nanowires

    DEFF Research Database (Denmark)

    Kwasny, Dorota; Andersen, Karsten Brandt; Frøhling, Kasper Bayer

    HROMOSOME translocation, which is a rearrangement of arms between two chromosomes, is a major group of chromosome abnormalities leading to cancer. As a result, two derivative chromosomes with sequences coming from both chromosomes are formed. The current translocation detection method is a Fluore...

  16. Chromosomes in the genesis and progression of ependymomas

    DEFF Research Database (Denmark)

    Rogatto, S R; Casartelli, C; Rainho, C A

    1993-01-01

    chromosomes in three cases. Structural rearrangements of chromosome 2 were a finding for all cases and involved loss of material at 2q32-34. Other structural chromosome abnormalities detected involved chromosomes 4, 6, 10, 11, 12, and X. We also reviewed data on 22 cases previously reported....

  17. Comparative chromosome painting in Carnivora and Pholidota.

    Science.gov (United States)

    Perelman, P L; Beklemisheva, V R; Yudkin, D V; Petrina, T N; Rozhnov, V V; Nie, W; Graphodatsky, A S

    2012-01-01

    The order of Carnivora has been very well characterized with over 50 species analyzed by chromosome painting and with painting probe sets made for 9 Carnivora species. Representatives of almost all families have been studied with few exceptions (Otariidae, Odobenidae, Nandiniidae, Prionodontidae). The patterns of chromosome evolution in Carnivora are discussed here. Overall, many Carnivora species retained karyotypes that only slightly differ from the ancestral carnivore karyotype. However, there are at least 3 families in which the ancestral carnivore karyotype has been severely rearranged - Canidae, Ursidae and Mephitidae. Here we report chromosome painting of yet another Carnivora species with a highly rearranged karyotype, Genetta pardina. Recurrent rearrangements make it difficult to define the ancestral chromosomal arrangement in several instances. Only 2 species of pangolins (Pholidota), a sister order of Carnivora, have been studied by chromosome painting. Future use of whole-genome sequencing data is discussed in the context of solving the questions that are beyond resolution of conventional banding techniques and chromosome painting. Copyright © 2012 S. Karger AG, Basel.

  18. Epilepsy and chromosome 18 abnormalities: A review.

    Science.gov (United States)

    Verrotti, Alberto; Carelli, Alessia; di Genova, Lorenza; Striano, Pasquale

    2015-11-01

    To analyze the various types of epilepsy in subjects with chromosome 18 aberrations in order to define epilepsy and its main clinical, electroclinical and prognostic aspects in chromosome 18 anomalies. A careful overview of recent works concerning chromosome 18 aberrations and epilepsy has been carried out considering the major groups of chromosomal 18 aberrations, identified using MEDLINE and EMBASE database from 1980 to 2015. Epilepsy seems to be particularly frequent in patients with trisomy or duplication of chromosome 18 with a prevalence of up to 65%. Approximately, over half of the patients develop epilepsy during the first year of life. Epilepsy can be focal or generalized; infantile spasms have also been reported. Brain imagines showed anatomical abnormalities in 38% of patients. Some antiepileptic drugs as valproic acid and carbamazepine were useful for treating seizures although a large majority of patients need polytherapy. Children with chromosomal 18 abnormalities can present different types of epilepsy, more frequently focal seizures in individuals with 18q- deletion syndrome, while both complex partial seizures and generalized tonic-clonic seizures have been described in patients who suffer for trisomy 18. Outcome in term of seizures frequency and duration seems to be variable and epilepsy is drug resistant in half of the children, especially in children with trisomy 18 and generalized epilepsy. Copyright © 2015 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

  19. The genomics of plant sex chromosomes.

    Science.gov (United States)

    Vyskot, Boris; Hobza, Roman

    2015-07-01

    Around six percent of flowering species are dioecious, with separate female and male individuals. Sex determination is mostly based on genetics, but morphologically distinct sex chromosomes have only evolved in a few species. Of these, heteromorphic sex chromosomes have been most clearly described in the two model species - Silene latifolia and Rumex acetosa. In both species, the sex chromosomes are the largest chromosomes in the genome. They are hence easily distinguished, can be physically separated and analyzed. This review discusses some recent experimental data on selected model dioecious species, with a focus on S. latifolia. Phylogenetic analyses show that dioecy in plants originated independently and repeatedly even within individual genera. A cogent question is whether there is genetic degeneration of the non-recombining part of the plant Y chromosome, as in mammals, and, if so, whether reduced levels of gene expression in the heterogametic sex are equalized by dosage compensation. Current data provide no clear conclusion. We speculate that although some transcriptome analyses indicate the first signs of degeneration, especially in S. latifolia, the evolutionary processes forming plant sex chromosomes in plants may, to some extent, differ from those in animals. Copyright © 2015. Published by Elsevier Ireland Ltd.

  20. Evolutionary stability of sex chromosomes in snakes.

    Science.gov (United States)

    Rovatsos, Michail; Vukić, Jasna; Lymberakis, Petros; Kratochvíl, Lukáš

    2015-12-22

    Amniote vertebrates possess various mechanisms of sex determination, but their variability is not equally distributed. The large evolutionary stability of sex chromosomes in viviparous mammals and birds was believed to be connected with their endothermy. However, some ectotherm lineages seem to be comparably conserved in sex determination, but previously there was a lack of molecular evidence to confirm this. Here, we document a stability of sex chromosomes in advanced snakes based on the testing of Z-specificity of genes using quantitative PCR (qPCR) across 37 snake species (our qPCR technique is suitable for molecular sexing in potentially all advanced snakes). We discovered that at least part of sex chromosomes is homologous across all families of caenophidian snakes (Acrochordidae, Xenodermatidae, Pareatidae, Viperidae, Homalopsidae, Colubridae, Elapidae and Lamprophiidae). The emergence of differentiated sex chromosomes can be dated back to about 60 Ma and preceded the extensive diversification of advanced snakes, the group with more than 3000 species. The Z-specific genes of caenophidian snakes are (pseudo)autosomal in the members of the snake families Pythonidae, Xenopeltidae, Boidae, Erycidae and Sanziniidae, as well as in outgroups with differentiated sex chromosomes such as monitor lizards, iguanas and chameleons. Along with iguanas, advanced snakes are therefore another example of ectothermic amniotes with a long-term stability of sex chromosomes comparable with endotherms. © 2015 The Author(s).

  1. Polytene chromosome map and inversion polymorphism in Drosophila mediopunctata

    Directory of Open Access Journals (Sweden)

    Ananina Galina

    2002-01-01

    Full Text Available Drosophila mediopunctata belongs to the tripunctata group, and is one of the commonest Drosophila species collected in some places in Brazil, especially in the winter. A standard map of the polytene chromosomes is presented. The breakpoints of the naturally occurring chromosomal rearrangements are marked on the map. The distribution of breaking points through the chromosomes of D. mediopunctata is apparently non-random. Chromosomes X, II and IV show inversion polymorphisms. Chromosome II is the most polymorphic, with 17 inversions, 8 inversions in the distal region and 9 in the proximal region. Chromosome X has four different gene arrangements, while chromosome IV has only two.

  2. Synchronous clear cell renal cell carcinoma and tubulocystic carcinoma: genetic evidence of independent ontogenesis and implications of chromosomal imbalances in tumor progression

    Directory of Open Access Journals (Sweden)

    Quiroga-Garza Gabriela

    2012-02-01

    Full Text Available Abstract Seven percent of renal cell carcinoma (RCC cases are diagnosed as "unclassified" RCC by morphology. Genetic profiling of RCCs helps define renal tumor subtypes, especially in cases where morphologic diagnosis is inconclusive. This report describes a patient with synchronous clear cell RCC (ccRCC and a tubulocystic renal carcinoma (TCRC in the same kidney, and discusses the pathologic features and genetic profile of both tumors. A 67 year-old male underwent CT scans for an unrelated medical event. Two incidental renal lesions were found and ultimately removed by radical nephrectomy. The smaller lesion had multiple small cystic spaces lined by hobnail cells with high nuclear grade separated by fibrous stroma. This morphology and the expression of proximal (CD10, AMACR and distal tubule cell (CK19 markers by immunohistochemistry supported the diagnosis of TCRC. The larger lesion was a typical ccRCC, with Fuhrman's nuclear grade 3 and confined to the kidney. Molecular characterization of both neoplasms using virtual karyotyping was performed to assess relatedness of these tumors. Low grade areas (Fuhrman grade 2 of the ccRCC showed loss of 3p and gains in chromosomes 5 and 7, whereas oncocytic areas displayed additional gain of 2p and loss of 10q; the high grade areas (Fuhrman grade 3 showed several additional imbalances. In contrast, the TCRC demonstrated a distinct profile with gains of chromosomes 8 and 17 and loss of 9. In conclusion, ccRCC and TCRC show distinct genomic copy number profiles and chromosomal imbalances in TCRC might be implicated in the pathogenesis of this tumor. Second, the presence of a ccRCC with varying degrees of differentiation exemplifies the sequence of chromosomal imbalances acquired during tumor progression. Virtual Slides The virtual slide(s for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1790525735655283

  3. Synchronous clear cell renal cell carcinoma and tubulocystic carcinoma: genetic evidence of independent ontogenesis and implications of chromosomal imbalances in tumor progression.

    Science.gov (United States)

    Quiroga-Garza, Gabriela; Piña-Oviedo, Sergio; Cuevas-Ocampo, Karime; Goldfarb, Richard; Schwartz, Mary R; Ayala, Alberto G; Monzon, Federico A

    2012-02-27

    Seven percent of renal cell carcinoma (RCC) cases are diagnosed as "unclassified" RCC by morphology. Genetic profiling of RCCs helps define renal tumor subtypes, especially in cases where morphologic diagnosis is inconclusive. This report describes a patient with synchronous clear cell RCC (ccRCC) and a tubulocystic renal carcinoma (TCRC) in the same kidney, and discusses the pathologic features and genetic profile of both tumors. A 67 year-old male underwent CT scans for an unrelated medical event. Two incidental renal lesions were found and ultimately removed by radical nephrectomy. The smaller lesion had multiple small cystic spaces lined by hobnail cells with high nuclear grade separated by fibrous stroma. This morphology and the expression of proximal (CD10, AMACR) and distal tubule cell (CK19) markers by immunohistochemistry supported the diagnosis of TCRC. The larger lesion was a typical ccRCC, with Fuhrman's nuclear grade 3 and confined to the kidney. Molecular characterization of both neoplasms using virtual karyotyping was performed to assess relatedness of these tumors. Low grade areas (Fuhrman grade 2) of the ccRCC showed loss of 3p and gains in chromosomes 5 and 7, whereas oncocytic areas displayed additional gain of 2p and loss of 10q; the high grade areas (Fuhrman grade 3) showed several additional imbalances. In contrast, the TCRC demonstrated a distinct profile with gains of chromosomes 8 and 17 and loss of 9. In conclusion, ccRCC and TCRC show distinct genomic copy number profiles and chromosomal imbalances in TCRC might be implicated in the pathogenesis of this tumor. Second, the presence of a ccRCC with varying degrees of differentiation exemplifies the sequence of chromosomal imbalances acquired during tumor progression. The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1790525735655283.

  4. Secondary tetrasomic segregation of MDH-B and preferential pairing of homeologues in rainbow trout.

    Science.gov (United States)

    Allendorf, F W; Danzmann, R G

    1997-04-01

    We examined the inheritance of allelic variation at an isozyme locus, MDH-B, duplicated by ancestral polyploidy in salmonid fishes. We detected only disomic segregation in females. Segregation ratios in males were best explained by a mixture of disomic and tetrasomic inheritance. We propose a two-stage model of pairing in male meiosis in which, first, homologous chromosomes pair and recombine in the proximal region of the chromosome. Next, homeologous chromosomes pair and recombine distally. We suggest that this type of tetrasomic inheritance in which centromeres segregate disomically should be referred to as "secondary tetrasomy" to distinguish it from tetrasomy involving entire chromosomes (i.e., "primary tetrasomy"). Differences in segregation ratios between males indicate differences between individuals in the amount of recombination between homeologous chromosomes. We also consider the implication of these results for estimation of allele frequencies at duplicated loci in salmonid populations.

  5. Small supernumerary marker chromosomes (sSMC in humans; are there B chromosomes hidden among them

    Directory of Open Access Journals (Sweden)

    Ogilvie Caroline

    2008-06-01

    Full Text Available Abstract Background Small supernumerary marker chromosomes (sSMC and B-chromosomes represent a heterogeneous collection of chromosomes added to the typical karyotype, and which are both small in size. They may consist of heterochromatic and/or euchromatic material. Also a predominance of maternal transmission was reported for both groups. Even though sSMC and B-chromosomes show some similarity it is still an open question if B-chromosomes are present among the heterogeneous group of sSMC. According to current theories, sSMC would need drive, drift or beneficial effects to increase in frequency in order to become B chromosome. However, up to now no B-chromosomes were described in human. Results Here we provide first evidence and discuss, that among sSMC B-chromosomes might be hidden. We present two potential candidates which may already be, or may in future evolve into B chromosomes in human: (i sSMC cases where the marker is stainable only by DNA derived from itself; and (ii acrocentric-derived inverted duplication sSMC without associated clinical phenotype. Here we report on the second sSMC stainable exclusively by its own DNA and show that for acrocentric derived sSMC 3.9× more are familial cases than reported for other sSMC. Conclusion The majority of sSMC are not to be considered as B-chromosomes. Nonetheless, a minority of sSMC show similarities to B-chromosomes. Further studies are necessary to come to final conclusions for that problem.

  6. Sequencing of individual chromosomes of plant pathogenic Fusarium oxysporum.

    Science.gov (United States)

    Kashiwa, Takeshi; Kozaki, Toshinori; Ishii, Kazuo; Turgeon, B Gillian; Teraoka, Tohru; Komatsu, Ken; Arie, Tsutomu

    2017-01-01

    A small chromosome in reference isolate 4287 of F. oxysporum f. sp. lycopersici (Fol) has been designated as a 'pathogenicity chromosome' because it carries several pathogenicity related genes such as the Secreted In Xylem (SIX) genes. Sequence assembly of small chromosomes in other isolates, based on a reference genome template, is difficult because of karyotype variation among isolates and a high number of sequences associated with transposable elements. These factors often result in misassembly of sequences, making it unclear whether other isolates possess the same pathogenicity chromosome harboring SIX genes as in the reference isolate. To overcome this difficulty, single chromosome sequencing after Contour-clamped Homogeneous Electric Field (CHEF) separation of chromosomes was performed, followed by de novo assembly of sequences. The assembled sequences of individual chromosomes were consistent with results of probing gels of CHEF separated chromosomes with SIX genes. Individual chromosome sequencing revealed that several SIX genes are located on a single small chromosome in two pathogenic forms of F. oxysporum, beyond the reference isolate 4287, and in the cabbage yellows fungus F. oxysporum f. sp. conglutinans. The particular combination of SIX genes on each small chromosome varied. Moreover, not all SIX genes were found on small chromosomes; depending on the isolate, some were on big chromosomes. This suggests that recombination of chromosomes and/or translocation of SIX genes may occur frequently. Our method improves sequence comparison of small chromosomes among isolates. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Additional chromosome abnormalities in chronic myeloid leukemia

    Directory of Open Access Journals (Sweden)

    Hui-Hua Hsiao

    2011-02-01

    Full Text Available The Philadelphia (Ph chromosome and/or Breakpoint cluster region-Abelson leukemia virus oncogene transcript are unique markers for chronic myeloid leukemia (CML. However, CML demonstrates heterogeneous presentations and outcomes. We analyzed the cytogenetic and molecular results of CML patients to evaluate their correlation with clinical presentations and outcome. A total of 84 newly diagnosed CML patients were enrolled in the study. Patients were treated according to disease status. Bone marrow samples were obtained to perform cytogenetic and molecular studies. Clinical presentations, treatment courses, and survival were reviewed retrospectively. Among 84 patients, 72 had chronic phase and 12 had accelerated phase CML. Cytogenetic study showed 69 (82.1% with the classic Ph chromosome, 6 (7.2% with a variant Ph chromosome, and 9 (10.7% with additional chromosome abnormalities. Fifty-four (64.3% cases harbored b3a2 transcripts, 29 (34.5% had b2a2 transcript, and 1 had e19a2 transcript. There was no difference in clinical presentations between different cytogenetic and molecular groups; however, additional chromosome abnormalities were significantly associated with the accelerated phase. Imatinib therapy was an effective treatment, as measured by cytogenetic response, when administered as first- and second-line therapy in chronic phase patients. Survival analysis showed that old age, additional chromosome abnormalities, high Sokal score, and no cytogenetic response in second-line therapy had a significant poor impact (p<0.05. In conclusion, we presented the cytogenetic and molecular pattern of CML patients and demonstrated that the additional chromosome abnormality was associated with poor outcome.

  8. Klinefelter syndrome and other sex chromosomal aneuploidies

    Directory of Open Access Journals (Sweden)

    Graham John M

    2006-10-01

    Full Text Available Abstract The term Klinefelter syndrome (KS describes a group of chromosomal disorder in which there is at least one extra X chromosome to a normal male karyotype, 46,XY. XXY aneuploidy is the most common disorder of sex chromosomes in humans, with prevalence of one in 500 males. Other sex chromosomal aneuploidies have also been described, although they are much less frequent, with 48,XXYY and 48,XXXY being present in 1 per 17,000 to 1 per 50,000 male births. The incidence of 49,XXXXY is 1 per 85,000 to 100,000 male births. In addition, 46,XX males also exist and it is caused by translocation of Y material including sex determining region (SRY to the X chromosome during paternal meiosis. Formal cytogenetic analysis is necessary to make a definite diagnosis, and more obvious differences in physical features tend to be associated with increasing numbers of sex chromosomes. If the diagnosis is not made prenatally, 47,XXY males may present with a variety of subtle clinical signs that are age-related. In infancy, males with 47,XXY may have chromosomal evaluations done for hypospadias, small phallus or cryptorchidism, developmental delay. The school-aged child may present with language delay, learning disabilities, or behavioral problems. The older child or adolescent may be discovered during an endocrine evaluation for delayed or incomplete pubertal development with eunuchoid body habitus, gynecomastia, and small testes. Adults are often evaluated for infertility or breast malignancy. Androgen replacement therapy should begin at puberty, around age 12 years, in increasing dosage sufficient to maintain age appropriate serum concentrations of testosterone, estradiol, follicle stimulating hormone (FSH, and luteinizing hormone (LH. The effects on physical and cognitive development increase with the number of extra Xs, and each extra X is associated with an intelligence quotient (IQ decrease of approximately 15–16 points, with language most affected

  9. Molecular mapping of chromosomes 17 and X

    Energy Technology Data Exchange (ETDEWEB)

    Barker, D.F.

    1991-01-15

    Progress toward the construction of high density genetic maps of chromosomes 17 and X has been made by isolating and characterizing a relatively large set of polymorphic probes for each chromosome and using these probes to construct genetic maps. We have mapped the same polymorphic probes against a series of chromosome breakpoints on X and 17. The probes could be assigned to over 30 physical intervals on the X chromosome and 7 intervals on 17. In many cases, this process resulted in improved characterization of the relative locations of the breakpoints with respect to each other and the definition of new physical intervals. The strategy for isolation of the polymorphic clones utilized chromosome specific libraries of 1--15 kb segments from each of the two chromosomes. From these libraries, clones were screened for those detecting restriction fragment length polymorphisms. The markers were further characterized, the chromosomal assignments confirmed and in most cases segments of the original probes were subcloned into plasmids to produce probes with improved signal to noise ratios for use in the genetic marker studies. The linkage studies utilize the CEPH reference families and other well-characterized families in our collection which have been used for genetic disease linkage work. Preliminary maps and maps of portions of specific regions of 17 and X are provided. We have nearly completed a map of the 1 megabase Mycoplasma arthritidis genome by applying these techniques to a lambda phage library of its genome. We have found bit mapping to be an efficient means to organize a contiguous set of overlapping clones from a larger genome.

  10. Sequencing papaya X and Yh chromosomes reveals molecular basis of incipient sex chromosome evolution.

    Science.gov (United States)

    Wang, Jianping; Na, Jong-Kuk; Yu, Qingyi; Gschwend, Andrea R; Han, Jennifer; Zeng, Fanchang; Aryal, Rishi; VanBuren, Robert; Murray, Jan E; Zhang, Wenli; Navajas-Pérez, Rafael; Feltus, F Alex; Lemke, Cornelia; Tong, Eric J; Chen, Cuixia; Wai, Ching Man; Singh, Ratnesh; Wang, Ming-Li; Min, Xiang Jia; Alam, Maqsudul; Charlesworth, Deborah; Moore, Paul H; Jiang, Jiming; Paterson, Andrew H; Ming, Ray

    2012-08-21

    Sex determination in papaya is controlled by a recently evolved XY chromosome pair, with two slightly different Y chromosomes controlling the development of males (Y) and hermaphrodites (Y(h)). To study the events of early sex chromosome evolution, we sequenced the hermaphrodite-specific region of the Y(h) chromosome (HSY) and its X counterpart, yielding an 8.1-megabase (Mb) HSY pseudomolecule, and a 3.5-Mb sequence for the corresponding X region. The HSY is larger than the X region, mostly due to retrotransposon insertions. The papaya HSY differs from the X region by two large-scale inversions, the first of which likely caused the recombination suppression between the X and Y(h) chromosomes, followed by numerous additional chromosomal rearrangements. Altogether, including the X and/or HSY regions, 124 transcription units were annotated, including 50 functional pairs present in both the X and HSY. Ten HSY genes had functional homologs elsewhere in the papaya autosomal regions, suggesting movement of genes onto the HSY, whereas the X region had none. Sequence divergence between 70 transcripts shared by the X and HSY revealed two evolutionary strata in the X chromosome, corresponding to the two inversions on the HSY, the older of which evolved about 7.0 million years ago. Gene content differences between the HSY and X are greatest in the older stratum, whereas the gene content and order of the collinear regions are identical. Our findings support theoretical models of early sex chromosome evolution.

  11. Marked chromosomes associations in catarrhine monkeys, with a note on chromosome associations in other primate groups

    NARCIS (Netherlands)

    Boer, L.E.M. de

    In metaphase figures, obtained from cultures of whole blood, associations of the marked chromosomes were found in species of the following genera: Macaca, Cercocebus, Cercopithecus and Symphalangus. The different types of these associations are discussed. A note is given on chromosome associations

  12. Tracking of chromosome dynamics in live Streptococcus pneumoniae reveals that transcription promotes chromosome segregation

    NARCIS (Netherlands)

    Kjos, Morten; Veening, Jan-Willem

    Chromosome segregation is an essential part of the bacterial cell cycle but is poorly characterized in oval-shaped streptococci. Using time-lapse fluorescence microscopy and total internal reflection fluorescence microscopy, we have tracked the dynamics of chromosome segregation in live cells of the

  13. The Chromosomal Passenger Complex Is Required for Meiotic Acentrosomal Spindle Assembly and Chromosome Biorientation

    Science.gov (United States)

    Radford, Sarah J.; Jang, Janet K.; McKim, Kim S.

    2012-01-01

    DURING meiosis in the females of many species, spindle assembly occurs in the absence of the microtubule-organizing centers called centrosomes. In the absence of centrosomes, the nature of the chromosome-based signal that recruits microtubules to promote spindle assembly as well as how spindle bipolarity is established and the chromosomes orient correctly toward the poles is not known. To address these questions, we focused on the chromosomal passenger complex (CPC). We have found that the CPC localizes in a ring around the meiotic chromosomes that is aligned with the axis of the spindle at all stages. Using new methods that dramatically increase the effectiveness of RNA interference in the germline, we show that the CPC interacts with Drosophila oocyte chromosomes and is required for the assembly of spindle microtubules. Furthermore, chromosome biorientation and the localization of the central spindle kinesin-6 protein Subito, which is required for spindle bipolarity, depend on the CPC components Aurora B and Incenp. Based on these data we propose that the ring of CPC around the chromosomes regulates multiple aspects of meiotic cell division including spindle assembly, the establishment of bipolarity, the recruitment of important spindle organization factors, and the biorientation of homologous chromosomes. PMID:22865736

  14. Exchange of core chromosomes and horizontal transfer of lineage-specific chromosomes in Fusarium oxysporum.

    Science.gov (United States)

    Vlaardingerbroek, Ido; Beerens, Bas; Rose, Laura; Fokkens, Like; Cornelissen, Ben J C; Rep, Martijn

    2016-11-01

    Horizontal transfer of supernumerary or lineage-specific (LS) chromosomes has been described in a number of plant pathogenic filamentous fungi. So far it was not known whether transfer is restricted to chromosomes of certain size or properties, or whether 'core' chromosomes can also undergo horizontal transfer. We combined a directed and a non-biased approach to determine whether such restrictions exist. Selection genes were integrated into the genome of a strain of Fusarium oxysporum pathogenic on tomato, either targeted to specific chromosomes by homologous recombination or integrated randomly into the genome. By testing these strains for transfer of the marker to another strain we could confirm transfer of a previously described mobile pathogenicity chromosome. Surprisingly, we also identified strains in which (parts of) core chromosomes were transferred. Whole genome sequencing revealed that this was accompanied by the loss of the homologous region from the recipient strain. Remarkably, transfer of the mobile pathogenicity chromosome always accompanied this exchange of core chromosomes. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

  15. Reassignment of chicken W chromosome sequences to the Z chromosome by fluorescence in situ hybridization (FISH).

    Science.gov (United States)

    Stiglec, R; Ezaz, T; Graves, J A M

    2007-01-01

    There is much interest in the gene content of the small heterochromatic W chromosome of the chicken, on the supposition that it may contain sex-determining genes. A considerable region in the chicken genome has been assigned to the W chromosome on the basis of its repetitive sequences. Using fluorescent in situ hybridization (FISH) we localized five Bacterial Artificial Chromosomes (BACs) onto female chicken metaphase spreads. We physically mapped these BACs to the Z chromosome. The chicken genome database, however, assigned all five BACs to the W chromosome. Our results demonstrate that the 17 genes on these BACs are Z-specific, and points to the inadequacy of assigning regions of the genome based exclusively on repetitive sequences. Copyright 2007 S. Karger AG, Basel.

  16. Mechanisms of ring chromosome formation in 11 cases of human ring chromosome 21

    DEFF Research Database (Denmark)

    McGinniss, M J; Kazazian, H H; Stetten, G

    1992-01-01

    We studied the mechanism of ring chromosome 21 (r(21)) formation in 13 patients (11 unique r(21)s), consisting of 7 from five families with familial r(21) and 6 with de novo r(21). The copy number of chromosome 21 sequences in the rings of these patients was determined by quantitative dosage......), resulting in deletion of varying amounts of 21q22.1 to 21qter. The data from one individual who had a Down syndrome phenotype were consistent with asymmetric breakage and reunion of 21q sequences from an intermediate isochromosome or Robertsonian translocation chromosome as reported by Wong et al. Another......). The phenotype of patients correlated well with the extent of deletion or duplication of chromosome 21 sequences. These data demonstrate three mechanisms of r(21) formation and show that the phenotype of r(21) patients varies with the extent of chromosome 21 monosomy or trisomy....

  17. The database of chromosome imbalance regions and genes resided in lung cancer from Asian and Caucasian identified by array-comparative genomic hybridization

    Directory of Open Access Journals (Sweden)

    Lo Fang-Yi

    2012-06-01

    Full Text Available Abstract Background Cancer-related genes show racial differences. Therefore, identification and characterization of DNA copy number alteration regions in different racial groups helps to dissect the mechanism of tumorigenesis. Methods Array-comparative genomic hybridization (array-CGH was analyzed for DNA copy number profile in 40 Asian and 20 Caucasian lung cancer patients. Three methods including MetaCore analysis for disease and pathway correlations, concordance analysis between array-CGH database and the expression array database, and literature search for copy number variation genes were performed to select novel lung cancer candidate genes. Four candidate oncogenes were validated for DNA copy number and mRNA and protein expression by quantitative polymerase chain reaction (qPCR, chromogenic in situ hybridization (CISH, reverse transcriptase-qPCR (RT-qPCR, and immunohistochemistry (IHC in more patients. Results We identified 20 chromosomal imbalance regions harboring 459 genes for Caucasian and 17 regions containing 476 genes for Asian lung cancer patients. Seven common chromosomal imbalance regions harboring 117 genes, included gain on 3p13-14, 6p22.1, 9q21.13, 13q14.1, and 17p13.3; and loss on 3p22.2-22.3 and 13q13.3 were found both in Asian and Caucasian patients. Gene validation for four genes including ARHGAP19 (10q24.1 functioning in Rho activity control, FRAT2 (10q24.1 involved in Wnt signaling, PAFAH1B1 (17p13.3 functioning in motility control, and ZNF322A (6p22.1 involved in MAPK signaling was performed using qPCR and RT-qPCR. Mean gene dosage and mRNA expression level of the four candidate genes in tumor tissues were significantly higher than the corresponding normal tissues (PP=0.06. In addition, CISH analysis of patients indicated that copy number amplification indeed occurred for ARHGAP19 and ZNF322A genes in lung cancer patients. IHC analysis of paraffin blocks from Asian Caucasian patients demonstrated that the frequency of

  18. The database of chromosome imbalance regions and genes resided in lung cancer from Asian and Caucasian identified by array-comparative genomic hybridization.

    Science.gov (United States)

    Lo, Fang-Yi; Chang, Jer-Wei; Chang, I-Shou; Chen, Yann-Jang; Hsu, Han-Shui; Huang, Shiu-Feng Kathy; Tsai, Fang-Yu; Jiang, Shih Sheng; Kanteti, Rajani; Nandi, Suvobroto; Salgia, Ravi; Wang, Yi-Ching

    2012-06-12

    Cancer-related genes show racial differences. Therefore, identification and characterization of DNA copy number alteration regions in different racial groups helps to dissect the mechanism of tumorigenesis. Array-comparative genomic hybridization (array-CGH) was analyzed for DNA copy number profile in 40 Asian and 20 Caucasian lung cancer patients. Three methods including MetaCore analysis for disease and pathway correlations, concordance analysis between array-CGH database and the expression array database, and literature search for copy number variation genes were performed to select novel lung cancer candidate genes. Four candidate oncogenes were validated for DNA copy number and mRNA and protein expression by quantitative polymerase chain reaction (qPCR), chromogenic in situ hybridization (CISH), reverse transcriptase-qPCR (RT-qPCR), and immunohistochemistry (IHC) in more patients. We identified 20 chromosomal imbalance regions harboring 459 genes for Caucasian and 17 regions containing 476 genes for Asian lung cancer patients. Seven common chromosomal imbalance regions harboring 117 genes, included gain on 3p13-14, 6p22.1, 9q21.13, 13q14.1, and 17p13.3; and loss on 3p22.2-22.3 and 13q13.3 were found both in Asian and Caucasian patients. Gene validation for four genes including ARHGAP19 (10q24.1) functioning in Rho activity control, FRAT2 (10q24.1) involved in Wnt signaling, PAFAH1B1 (17p13.3) functioning in motility control, and ZNF322A (6p22.1) involved in MAPK signaling was performed using qPCR and RT-qPCR. Mean gene dosage and mRNA expression level of the four candidate genes in tumor tissues were significantly higher than the corresponding normal tissues (P<0.001~P=0.06). In addition, CISH analysis of patients indicated that copy number amplification indeed occurred for ARHGAP19 and ZNF322A genes in lung cancer patients. IHC analysis of paraffin blocks from Asian Caucasian patients demonstrated that the frequency of PAFAH1B1 protein overexpression was 68

  19. Origin of B chromosomes in the genus Astyanax (Characiformes, Characidae) and the limits of chromosome painting.

    Science.gov (United States)

    de A Silva, Duílio M Z; Daniel, Sandro Natal; Camacho, Juan Pedro M; Utsunomia, Ricardo; Ruiz-Ruano, Francisco J; Penitente, Manolo; Pansonato-Alves, José Carlos; Hashimoto, Diogo Teruo; Oliveira, Claudio; Porto-Foresti, Fábio; Foresti, Fausto

    2016-06-01

    Eukaryote genomes are frequently burdened with the presence of supernumerary (B) chromosomes. Their origin is frequently investigated by chromosome painting, under the hypothesis that sharing the repetitive DNA sequences contained in the painting probes is a sign of common descent. However, the intragenomic mobility of many anonymous DNA sequences contained in these probes (e.g., transposable elements) adds high uncertainty to this conclusion. Here we test the validity of chromosome painting to investigate B chromosome origin by comparing its results for seven B chromosome types in two fish species genus Astyanax, with those obtained (1) by means of the physical mapping of 18S ribosomal DNA (rDNA), H1 histone genes, the As51 satellite DNA and the (AC)15 microsatellite, and (2) by comparing the nucleotide sequence of one of these families (ITS regions from ribosomal DNA) between genomic DNA from B-lacking individuals in both species and the microdissected DNA from two metacentric B chromosomes found in these same species. Intra- and inter-specific painting suggested that all B chromosomes that were assayed shared homologous DNA sequences among them, as well as with a variable number of A chromosomes in each species. This finding would be consistent with a common origin for all seven B chromosomes analyzed. By contrast, the physical mapping of repetitive DNA sequences failed to give support to this hypothesis, as no more than two B-types shared a given repetitive DNA. Finally, sequence analysis of the ITS regions suggested that at least some of the B chromosomes could have had a common origin.

  20. Chromosomal polymorphism in the Sporothrix schenckii complex.

    Science.gov (United States)

    Sasaki, Alexandre A; Fernandes, Geisa F; Rodrigues, Anderson M; Lima, Fábio M; Marini, Marjorie M; Dos S Feitosa, Luciano; de Melo Teixeira, Marcus; Felipe, Maria Sueli Soares; da Silveira, José Franco; de Camargo, Zoilo P

    2014-01-01

    Sporotrichosis is a polymorphic disease caused by a complex of thermodimorphic fungi including S. brasiliensis, S. schenckii sensu stricto (s. str.), S. globosa and S. luriei. Humans and animals can acquire the disease through traumatic inoculation of propagules into the subcutaneous tissue. Despite the importance of sporotrichosis as a disease that can take epidemic proportions there are just a few studies dealing with genetic polymorphisms and genomic architecture of these pathogens. The main objective of this study was to investigate chromosomal polymorphisms and genomic organization among different isolates in the S. schenckii complex. We used pulsed field gel electrophoresis (PFGE) to separate chromosomal fragments of isolated DNA, followed by probe hybridization. Nine loci (β-tubulin, calmodulin, catalase, chitin synthase 1, Internal Transcribed Spacer, Pho85 cyclin-dependent kinase, protein kinase C Ss-2, G protein α subunit and topoisomerase II) were mapped onto chromosomal bands of Brazilian isolates of S. schenckii s. str. and S. brasiliensis. Our results revealed the presence of intra and interspecies polymorphisms in chromosome number and size. The gene hybridization analysis showed that closely related species in phylogenetic analysis had similar genetic organizations, mostly due to identification of synteny groups in chromosomal bands of similar sizes. Our results bring new insights into the genetic diversity and genome organization among pathogenic species in the Sporothrix schenckii complex.

  1. Chromosome-specific DNA Repeat Probes

    Energy Technology Data Exchange (ETDEWEB)

    Baumgartner, Adolf; Weier, Jingly Fung; Weier, Heinz-Ulrich G.

    2006-03-16

    In research as well as in clinical applications, fluorescence in situ hybridization (FISH) has gained increasing popularity as a highly sensitive technique to study cytogenetic changes. Today, hundreds of commercially available DNA probes serve the basic needs of the biomedical research community. Widespread applications, however, are often limited by the lack of appropriately labeled, specific nucleic acid probes. We describe two approaches for an expeditious preparation of chromosome-specific DNAs and the subsequent probe labeling with reporter molecules of choice. The described techniques allow the preparation of highly specific DNA repeat probes suitable for enumeration of chromosomes in interphase cell nuclei or tissue sections. In addition, there is no need for chromosome enrichment by flow cytometry and sorting or molecular cloning. Our PCR-based method uses either bacterial artificial chromosomes or human genomic DNA as templates with {alpha}-satellite-specific primers. Here we demonstrate the production of fluorochrome-labeled DNA repeat probes specific for human chromosomes 17 and 18 in just a few days without the need for highly specialized equipment and without the limitation to only a few fluorochrome labels.

  2. Chromosomal Abnormality in Men with Impaired Spermatogenesis

    Directory of Open Access Journals (Sweden)

    Dana Mierla

    2014-03-01

    Full Text Available Background: Chromosomal abnormalities and Y chromosome microdeletions are regarded as two most frequent genetic causes associated with failure of spermatogenesis in the Caucasian population. Materials and Methods: To investigate the distribution of genetic defects in the Romanian population with azoospermia or severe oligozoospermia, karyotype analysis by G-banding was carried out in 850 idiopathic infertile men and in 49 fertile men with one or more children. Screening for microdeletions in the azoospermia factor (AZF region of Y chromosome was performed by multiplex polymerase chain reaction (PCR on a group of 67 patients with no detectable chromosomal abnormality. The results of the two groups were compared by a two-tailed Fisher’s exact test. Results: In our study chromosomal abnormalities were observed in 12.70% and 8.16% of infertile and fertile individuals respectively. Conclusion: Our data suggests that infertile men with severe azoospermia have higher incidences of genetic defects than fertile men and also patients from any other group. Infertile men with normal sperm present a higher rate of polymorphic variants. It is important to know whether there is a genetic cause of male infertility before patients are subjected to intracytoplasmic sperm injection (ICSI or testicular sperm extraction (TESE/ICSI treatment.

  3. Amphibian and Avian Karyotype Evolution: Insights from Lampbrush Chromosome Studies.

    Science.gov (United States)

    Zlotina, Anna; Dedukh, Dmitry; Krasikova, Alla

    2017-11-08

    Amphibian and bird karyotypes typically have a complex organization, which makes them difficult for standard cytogenetic analysis. That is, amphibian chromosomes are generally large, enriched with repetitive elements, and characterized by the absence of informative banding patterns. The majority of avian karyotypes comprise a small number of relatively large macrochromosomes and numerous tiny morphologically undistinguishable microchromosomes. A good progress in investigation of amphibian and avian chromosome evolution became possible with the usage of giant lampbrush chromosomes typical for growing oocytes. Due to the giant size, peculiarities of organization and enrichment with cytological markers, lampbrush chromosomes can serve as an opportune model for comprehensive high-resolution cytogenetic and cytological investigations. Here, we review the main findings on chromosome evolution in amphibians and birds that were obtained using lampbrush chromosomes. In particular, we discuss the data on evolutionary chromosomal rearrangements, accumulation of polymorphisms, evolution of sex chromosomes as well as chromosomal changes during clonal reproduction of interspecies hybrids.

  4. Generation of multicolor banding probes for chromosomes of different species

    Directory of Open Access Journals (Sweden)

    Kosyakova Nadezda

    2013-02-01

    Full Text Available Abstract Background The multicolor banding (MCB/mBAND technique provides a unique opportunity to characterize intrachromosomal rearrangements and to determine chromosomal breakpoints. Until recently, MCB probes have only been available for human and some murine chromosomes. Generation of MCB probes for chromosomes of other species, useful and required in many cytogenetics research fields, was limited by technical difficulties. MCB probes are established by chromosome microdissection followed by whole genomic DNA amplification. However, unambiguous identification of the target chromosome is required for MCB-probe establishment. Previously proposed protocols suggested G-banding staining or preliminary FISH with whole chromosome paints (WCP as methods to identify the chromosome of interest. Results Here we present a complete workflow for MCB probe generation for those cases and species where chromosome morphology is too challenging to recognize target chromosomes by conventional methods and where WCP probes are not available. The workflow was successfully applied for murine chromosomes that are difficult to identify unambiguously. Additionally, we showed that glass-needle based microdissection enables establishment of a whole set of WCP paints by microdissection of individual chromosomes of a single metaphase Conclusions The present method can be applied for generation of whole or region-specific DNA probes for species, where karyotyping of G-banded chromosomes is challenging due to similar chromosome morphology and/or chromosome banding patterns.

  5. Generation of multicolor banding probes for chromosomes of different species.

    Science.gov (United States)

    Kosyakova, Nadezda; Hamid, Ahmed Basheer; Chaveerach, Arunrat; Pinthong, Krit; Siripiyasing, Pornnarong; Supiwong, Weerayuth; Romanenko, Svetlana; Trifonov, Vladimir; Fan, Xiaobo

    2013-02-04

    The multicolor banding (MCB/mBAND) technique provides a unique opportunity to characterize intrachromosomal rearrangements and to determine chromosomal breakpoints. Until recently, MCB probes have only been available for human and some murine chromosomes. Generation of MCB probes for chromosomes of other species, useful and required in many cytogenetics research fields, was limited by technical difficulties. MCB probes are established by chromosome microdissection followed by whole genomic DNA amplification. However, unambiguous identification of the target chromosome is required for MCB-probe establishment. Previously proposed protocols suggested G-banding staining or preliminary FISH with whole chromosome paints (WCP) as methods to identify the chromosome of interest. Here we present a complete workflow for MCB probe generation for those cases and species where chromosome morphology is too challenging to recognize target chromosomes by conventional methods and where WCP probes are not available. The workflow was successfully applied for murine chromosomes that are difficult to identify unambiguously. Additionally, we showed that glass-needle based microdissection enables establishment of a whole set of WCP paints by microdissection of individual chromosomes of a single metaphase The present method can be applied for generation of whole or region-specific DNA probes for species, where karyotyping of G-banded chromosomes is challenging due to similar chromosome morphology and/or chromosome banding patterns.

  6. [Penoscrotal hypospadias with XXYY chromosome pattern].

    Science.gov (United States)

    Neugebauer, H; Steichen-Gersdorf, E; Glatzl, J

    1991-01-01

    This is the report of a boy, 2 years and 4 months of age who presented with an penoscrotal hypospadia with normal appearing testes. Physical examination and routine laboratory tests revealed--besides a broad base of the nose and clinodactyly--no abnormality. The boy exhibits a normal speech development with retarded global intellectual development. Investigation of the hormon status revealed a disturbance of testosteron secretion and a hypergonadotropic hypogonadism. Chromosomal analysis in lymphocyte cultures revealed a XXYY karyotyp. This chromosomal pattern is seen in 3% of patients with Klinefelter syndrom; the estimated frequency is 1 in 25,000 population. A combination of an XXYY chromosomal pattern with a penoscrotal hypospadia has not been reported in the literature so far.

  7. Chromosomal abnormalities in a psychiatric population

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, K.E.; Lubetsky, M.J.; Wenger, S.L.; Steele, M.W. [Univ. of Pittsburgh Medical Center, PA (United States)

    1995-02-27

    Over a 3.5 year period of time, 345 patients hospitalized for psychiatric problems were evaluated cytogenetically. The patient population included 76% males and 94% children with a mean age of 12 years. The criteria for testing was an undiagnosed etiology for mental retardation and/or autism. Cytogenetic studies identified 11, or 3%, with abnormal karyotypes, including 4 fragile X positive individuals (2 males, 2 females), and 8 with chromosomal aneuploidy, rearrangements, or deletions. While individuals with chromosomal abnormalities do not demonstrate specific behavioral, psychiatric, or developmental problems relative to other psychiatric patients, our results demonstrate the need for an increased awareness to order chromosomal analysis and fragile X testing in those individuals who have combinations of behavioral/psychiatric, learning, communication, or cognitive disturbance. 5 refs., 1 fig., 2 tabs.

  8. Can molecular cell biology explain chromosome motions?

    Directory of Open Access Journals (Sweden)

    Gagliardi L

    2011-05-01

    Full Text Available Abstract Background Mitotic chromosome motions have recently been correlated with electrostatic forces, but a lingering "molecular cell biology" paradigm persists, proposing binding and release proteins or molecular geometries for force generation. Results Pole-facing kinetochore plates manifest positive charges and interact with negatively charged microtubule ends providing the motive force for poleward chromosome motions by classical electrostatics. This conceptual scheme explains dynamic tracking/coupling of kinetochores to microtubules and the simultaneous depolymerization of kinetochore microtubules as poleward force is generated. Conclusion We question here why cells would prefer complex molecular mechanisms to move chromosomes when direct electrostatic interactions between known bound charge distributions can accomplish the same task much more simply.

  9. The complete sequence of human chromosome 5

    Energy Technology Data Exchange (ETDEWEB)

    Schmutz, Jeremy; Martin, Joel; Terry, Astrid; Couronne, Olivier; Grimwood, Jane; Lowry, State; Gordon, Laurie A.; Scott, Duncan; Xie, Gary; Huang, Wayne; Hellsten, Uffe; Tran-Gyamfi, Mary; She, Xinwei; Prabhakar, Shyam; Aerts, Andrea; Altherr, Michael; Bajorek, Eva; Black, Stacey; Branscomb, Elbert; Caoile, Chenier; Challacombe, Jean F.; Chan, Yee Man; Denys, Mirian; Detter, Chris; Escobar, Julio; Flowers, Dave; Fotopulos, Dea; Glavina, Tijana; Gomez, Maria; Gonzales, Eidelyn; Goodstenin, David; Grigoriev, Igor; Groza, Matthew; Hammon, Nancy; Hawkins, Trevor; Haydu, Lauren; Israni, Sanjay; Jett, Jamie; Kadner, Kristen; Kimbal, Heather; Kobayashi, Arthur; Lopez, Frederick; Lou, Yunian; Martinez, Diego; Medina, Catherine; Morgan, Jenna; Nandkeshwar, Richard; Noonan, James P.; Pitluck, Sam; Pollard, Martin; Predki, Paul; Priest, James; Ramirez, Lucia; Rash, Sam; Retterer, James; Rodriguez, Alex; Rogers, Stephanie; Salamov, Asaf; Salazar, Angelica; Thayer, Nina; Tice, Hope; Tsai, Ming; Ustaszewska, Anna; Vo, Nu; Wheeler, Jeremy; Wu, Kevin; Yang, Joan; Dickson, Mark; Cheng, Jan-Fang; Eichler, Evan E.; Olsen, Anne; Pennacchio, Len A.; Rokhsar, Daniel S.; Richardson, Paul; Lucas, Susan M.; Myers, Richard M.; Rubin, Edward M.

    2004-04-15

    Chromosome 5 is one of the largest human chromosomes yet has one of the lowest gene densities. This is partially explained by numerous gene-poor regions that display a remarkable degree of noncoding and syntenic conservation with non-mammalian vertebrates, suggesting they are functionally constrained. In total, we compiled 177.7 million base pairs of highly accurate finished sequence containing 923 manually curated protein-encoding genes including the protocadherin and interleukin gene families and the first complete versions of each of the large chromosome 5 specific internal duplications. These duplications are very recent evolutionary events and play a likely mechanistic role, since deletions of these regions are the cause of debilitating disorders including spinal muscular atrophy (SMA).

  10. Can molecular cell biology explain chromosome motions?

    Science.gov (United States)

    Shain, Daniel H; Gagliardi, L John

    2011-05-27

    Mitotic chromosome motions have recently been correlated with electrostatic forces, but a lingering "molecular cell biology" paradigm persists, proposing binding and release proteins or molecular geometries for force generation. Pole-facing kinetochore plates manifest positive charges and interact with negatively charged microtubule ends providing the motive force for poleward chromosome motions by classical electrostatics. This conceptual scheme explains dynamic tracking/coupling of kinetochores to microtubules and the simultaneous depolymerization of kinetochore microtubules as poleward force is generated. We question here why cells would prefer complex molecular mechanisms to move chromosomes when direct electrostatic interactions between known bound charge distributions can accomplish the same task much more simply. © 2011 Shain and Gagliardi; licensee BioMed Central Ltd.

  11. Mapping genes to human chromosome 19

    Energy Technology Data Exchange (ETDEWEB)

    Connolly, Sarah [Univ. of Illinois, Urbana-Champaign, IL (United States); Lawrence Livermore National Lab., CA (United States)

    1996-05-01

    For this project, 22 Expressed Sequence Tags (ESTs) were fine mapped to regions of human chromosome 19. An EST is a short DNA sequence that occurs once in the genome and corresponds to a single expressed gene. {sup 32}P-radiolabeled probes were made by polymerase chain reaction for each EST and hybridized to filters containing a chromosome 19-specific cosmid library. The location of the ESTs on the chromosome was determined by the location of the ordered cosmid to which the EST hybridized. Of the 22 ESTs that were sublocalized, 6 correspond to known genes, and 16 correspond to anonymous genes. These localized ESTs may serve as potential candidates for disease genes, as well as markers for future physical mapping.

  12. Non-disjunction of chromosome 18

    DEFF Research Database (Denmark)

    Bugge, M; Collins, A; Petersen, M B

    1998-01-01

    A sample of 100 trisomy 18 conceptuses analysed separately and together with a published sample of 61 conceptuses confirms that an error in maternal meiosis II (MII) is the most frequent cause of non-disjunction for chromosome 18. This is unlike all other human trisomies that have been studied......, which show a higher frequency in maternal meiosis I (MI). Maternal MI trisomy 18 shows a low frequency of recombination in proximal p and medial q, but not the reduction in proximal q observed in chromosome 21 MI non-disjunction. Maternal MII non-disjunction does not fit the entanglement model...... that predicts increased recombination, especially near the centromere. Whereas recent data on MII trisomy 21 show the predicted increase in recombination proximally, maternal MII trisomy 18 has non-significantly reduced recombination. Therefore, chromosome-specific factors must complicate the simple model...

  13. Origin of extra chromosome in Patau syndrome.

    Science.gov (United States)

    Ishikiriyama, S; Niikawa, N

    1984-01-01

    Five live-born infants with Patau syndrome were studied for the nondisjunctional origin of the extra chromosome. Transmission modes of chromosomes 13 from parents to a child were determined using both QFQ- and RFA-heteromorphisms as markers, and the origin was ascertained in all of the patients. The extra chromosome had originated in nondisjunction at the maternal first meiotic division in two patients, at the maternal second meiosis in other two, and at the paternal first meiosis in the remaining one. Summarizing the results of the present study, together with those of the previous studies on a liveborn and abortuses with trisomy 13, nondisjunction at the maternal and the paternal meiosis occurred in this trisomy in the ratio of 14:3. This ratio is not statistically different from that inferred from the previous studies for Down syndrome. These findings suggest that there may be a fundamental mechanism common to the occurrence of nondisjunction in the acrocentric trisomies.

  14. The X--a sexy chromosome.

    Science.gov (United States)

    Graves, J A; Delbridge, M L

    2001-12-01

    There is new and convincing evidence that the mammalian X chromosome, as well as the Y chromosome, contains an atypically high proportion of genes involved in sex and reproduction (SRR genes). Here we consider alternative explanations for this concentration. One possibility is that a particularly well-endowed autosome was "chosen" for a career as a sex chromosome. Alternatively, the high concentration of SRR genes may have resulted from the accumulation of these genes on the X after the degradation of the Y, either by transposition of autosomal SRR genes to a "selfish X", or by acquisition of SRR functions by widely expressed genes on the X. We suggest experiments to distinguish these possibilities, and speculate on the implications of gathering evidence that genes with other functions, too, are not distributed uniformly over the genome. Copyright 2001 John Wiley & Sons, Inc.

  15. Bias of purine stretches in sequenced chromosomes

    DEFF Research Database (Denmark)

    Ussery, David; Soumpasis, Dikeos Mario; Brunak, Søren

    2002-01-01

    We examined more than 700 DNA sequences (full length chromosomes and plasmids) for stretches of purines (R) or pyrimidines (Y) and alternating YR stretches; such regions will likely adopt structures which are different from the canonical B-form. Since one turn of the DNA helix is roughly 10 bp, we...... to contain 1.0% of purine tracts and also 1.0% of the alternating pyr/pur tracts. In the vast majority of cases, there are more purine tracts than would be expected from a random sequence, with an average of 3.5%, significantly larger than the expectation value. The fraction of the chromosomes containing pyr......, in eukaryotes there is an abundance of long stretches of purines or alternating purine/pyrimidine tracts, which cannot be explained in this way; these sequences are likely to play an important role in eukaryotic chromosome organisation....

  16. Human male meiotic sex chromosome inactivation.

    Directory of Open Access Journals (Sweden)

    Marieke de Vries

    Full Text Available In mammalian male gametogenesis the sex chromosomes are distinctive in both gene activity and epigenetic strategy. At first meiotic prophase the heteromorphic X and Y chromosomes are placed in a separate chromatin domain called the XY body. In this process, X,Y chromatin becomes highly phosphorylated at S139 of H2AX leading to the repression of gonosomal genes, a process known as meiotic sex chromosome inactivation (MSCI, which has been studied best in mice. Post-meiotically this repression is largely maintained. Disturbance of MSCI in mice leads to harmful X,Y gene expression, eventuating in spermatocyte death and sperm heterogeneity. Sperm heterogeneity is a characteristic of the human male. For this reason we were interested in the efficiency of MSCI in human primary spermatocytes. We investigated MSCI in pachytene spermatocytes of seven probands: four infertile men and three fertile controls, using direct and indirect in situ methods. A considerable degree of variation in the degree of MSCI was detected, both between and within probands. Moreover, in post-meiotic stages this variation was observed as well, indicating survival of spermatocytes with incompletely inactivated sex chromosomes. Furthermore, we investigated the presence of H3K9me3 posttranslational modifications on the X and Y chromatin. Contrary to constitutive centromeric heterochromatin, this heterochromatin marker did not specifically accumulate on the XY body, with the exception of the heterochromatic part of the Y chromosome. This may reflect the lower degree of MSCI in man compared to mouse. These results point at relaxation of MSCI, which can be explained by genetic changes in sex chromosome composition during evolution and candidates as a mechanism behind human sperm heterogeneity.

  17. Chromosomes of Protists: The crucible of evolution.

    Science.gov (United States)

    Soyer-Gobillard, Marie-Odile; Dolan, Michael F

    2015-12-01

    As early as 1925, the great protozoologist Edouard Chatton classified microorganisms into two categories, the prokaryotic and the eukaryotic microbes, based on light microscopical observation of their nuclear organization. Now, by means of transmission electron microscopy, we know that prokaryotic microbes are characterized by the absence of nuclear envelope surrounding the bacterial chromosome, which is more or less condensed and whose chromatin is deprived of histone proteins but presents specific basic proteins. Eukaryotic microbes, the protists, have nuclei surrounded by a nuclear envelope and have chromosomes more or less condensed, with chromatin-containing histone proteins organized into nucleosomes. The extraordinary diversity of mitotic systems presented by the 36 phyla of protists (according to Margulis et al., Handbook of Protoctista, 1990) is in contrast to the relative homogeneity of their chromosome structure and chromatin components. Dinoflagellates are the exception to this pattern. The phylum is composed of around 2000 species, and characterized by unique features including their nucleus (dinokaryon), dinomitosis, chromosome organization and chromatin composition. Although their DNA synthesis is typically eukaryotic, dinoflagellates are the only eukaryotes in which the chromatin, organized into quasi-permanently condensed chromosomes, is in some species devoid of histones and nucleosomes. In these cases, their chromatin contains specific DNA-binding basic proteins. The permanent compaction of their chromosomes throughout the cell cycle raises the question of the modalities of their division and their transcription. Successful in vitro reconstitution of nucleosomes using dinoflagellate DNA and heterologous corn histones raises questions about dinoflagellate evolution and phylogeny. [Int Microbiol 18(4):209-216 (2015)]. Copyright© by the Spanish Society for Microbiology and Institute for Catalan Studies.

  18. From equator to pole: splitting chromosomes in mitosis and meiosis

    Science.gov (United States)

    Duro, Eris

    2015-01-01

    During eukaryotic cell division, chromosomes must be precisely partitioned to daughter cells. This relies on a mechanism to move chromosomes in defined directions within the parental cell. While sister chromatids are segregated from one another in mitosis and meiosis II, specific adaptations enable the segregation of homologous chromosomes during meiosis I to reduce ploidy for gamete production. Many of the factors that drive these directed chromosome movements are known, and their molecular mechanism has started to be uncovered. Here we review the mechanisms of eukaryotic chromosome segregation, with a particular emphasis on the modifications that ensure the segregation of homologous chromosomes during meiosis I. PMID:25593304

  19. DNA Repair Defects and Chromosomal Aberrations

    Science.gov (United States)

    Hada, Megumi; George, K. A.; Huff, J. L.; Pluth, J. M.; Cucinotta, F. A.

    2009-01-01

    Yields of chromosome aberrations were assessed in cells deficient in DNA doublestrand break (DSB) repair, after exposure to acute or to low-dose-rate (0.018 Gy/hr) gamma rays or acute high LET iron nuclei. We studied several cell lines including fibroblasts deficient in ATM (ataxia telangiectasia mutated; product of the gene that is mutated in ataxia telangiectasia patients) or NBS (nibrin; product of the gene mutated in the Nijmegen breakage syndrome), and gliomablastoma cells that are proficient or lacking in DNA-dependent protein kinase (DNA-PK) activity. Chromosomes were analyzed using the fluorescence in situ hybridization (FISH) chromosome painting method in cells at the first division post irradiation, and chromosome aberrations were identified as either simple exchanges (translocations and dicentrics) or complex exchanges (involving >2 breaks in 2 or more chromosomes). Gamma irradiation induced greater yields of both simple and complex exchanges in the DSB repair-defective cells than in the normal cells. The quadratic dose-response terms for both simple and complex chromosome exchanges were significantly higher for the ATM- and NBS-deficient lines than for normal fibroblasts. However, in the NBS cells the linear dose-response term was significantly higher only for simple exchanges. The large increases in the quadratic dose-response terms in these repair-defective cell lines points the importance of the functions of ATM and NBS in chromatin modifications to facilitate correct DSB repair and minimize the formation of aberrations. The differences found between ATM- and NBS-deficient cells at low doses suggest that important questions should with regard to applying observations of radiation sensitivity at high dose to low-dose exposures. For aberrations induced by iron nuclei, regression models preferred purely linear dose responses for simple exchanges and quadratic dose responses for complex exchanges. Relative biological effectiveness (RBE) factors of all of

  20. Design and chemical synthesis of eukaryotic chromosomes.

    Science.gov (United States)

    Xie, Ze-Xiong; Liu, Duo; Li, Bing-Zhi; Zhao, Meng; Zeng, Bo-Xuan; Wu, Yi; Shen, Yue; Lin, Tao; Yang, Ping; Dai, Junbiao; Cai, Yizhi; Yang, Huanming; Yuan, Ying-Jin

    2017-11-27

    Following the discovery of the DNA double helix structure and the advancement of genome sequencing, we have entered a promising stage with regard to genome writing. Recently, a milestone breakthrough was achieved in the chemical synthesis of designer yeast chromosomes. Here, we review the systematic approaches to the de novo synthesis of designer eukaryotic chromosomes, with an emphasis on technologies and methodologies that enable design, building, testing and debugging. The achievement of chemically synthesized genomes with customized genetic features offers an opportunity to rebuild genome organization, remold biological functions and promote life evolution, which will be of great benefit for application in medicine and industrial manufacturing.

  1. Microdissection and chromosome painting of X and B chromosomes in the grasshopper Eyprepocnemis plorans.

    Science.gov (United States)

    Teruel, M; Cabrero, J; Perfectti, F; Acosta, M J; Sánchez, A; Camacho, J P M

    2009-01-01

    The relative location of 2 repetitive DNAs, i.e. ribosomal (rDNA) and a tandemly repeated satellite DNA (satDNA), with respect to the centromere, suggested that B chromosomes in the grasshopper Eyprepocnemis plorans derived intraspecifically from the X chromosome. To test this hypothesis, we microdissected X and B chromosomes and amplified the obtained DNA by 2 different procedures, the conventional DOP-PCR method and the single-cell whole-genome amplification GenomePlex method. We then generated DNA probes to perform chromosome painting. Our results have confirmed that X and B chromosomes share many DNA sequences between them and with most of the autosomes, especially at locations where the satDNA and rDNA reside, in consistency with previous information. This supports the hypothesis of an intraspecific origin of B chromosomes in E. plorans. Nevertheless, the present results did not help to clarify whether Bs were derived from the X chromosome or else from 1 or more autosomes. (c) 2009 S. Karger AG, Basel.

  2. Maternal mosaicism of sex chromosome causes discordant sex chromosomal aneuploidies associated with noninvasive prenatal testing.

    Science.gov (United States)

    Wang, Leilei; Meng, Qian; Tang, Xinxin; Yin, Ting; Zhang, Jinglu; Yang, Shuting; Wang, Xuyun; Wu, Haiqian; Shi, Qingxi; Jenkins, Edmund C; Zhong, Nanbert; Gu, Ying

    2015-10-01

    To investigate the clinical efficiency of noninvasive prenatal test (NIPT) identifying fetal chromosomal aneuploidies. In the present study, 917 women with high-risk pregnancies were invited to participate in an NIPT trial based on an Illumina HiSeq massively parallel sequencing platform. Abnormal cases in NIPT were validated by karyotyping and fluorescence in situ hybridization (FISH) analysis. All of the participants' infants were examined clinically and followed up for at least 6 months. A total of 35 (3.82%) high-risk pregnancies were detected with abnormal results in NIPT, which included 25 cases (2.73%) of trisomy 21 (Tri21), four cases (0.44%) of trisomy 18 (Tri18), four cases (0.44%) of Turner syndrome (45, X), one cases (0.11%) of Klinefelter's syndrome (47, XXY), and one cases (0.11%) with lower X chromosome concentration. Further validation indicated that one case of Tri18 and the case with lower X chromosome concentration were false positive results (0.22%) in NIPT. Furthermore, it was found that the false positive case with lower X chromosome concentration in NIPT was caused by maternal sex chromosomal mosaicism (45, X and 46, XX). Our findings indicated that maternal mosaicism of sex chromosome could cause discordant sex chromosomal aneuploidies associated with NIPT. We highly recommended that maternal karyotype should be confirmed for the cases with abnormal results in NIPT. Copyright © 2015. Published by Elsevier B.V.

  3. Identification of novel translocation between short arm of chromosome 4 and long arm of chromosome 6 in an infertile man using Interphase Chromosome Profiling (ICP).

    Science.gov (United States)

    Kaul, S; Kaur, H; Vats, S K S; Chawla, J; Jindal, R; Khetarpal, P

    2018-02-07

    Conventional cytogenetics has always been a favourite to detect chromosomal aberrations. Carriers of chromosomal translocation are often phenotypically normal but are infertile. Couples are often advised to go for karyotyping, but culture failure or improper metaphase spread with poor banding often makes the analysis difficult. We report here a novel translocation between short arm of chromosome 4 and long arm of chromosome 6 in an infertile man using an advanced molecular cytogenetic technique of Interphase Chromosome Profiling (ICP). © 2018 Blackwell Verlag GmbH.

  4. A maximum likelihood algorithm for reconstructing 3D structures of human chromosomes from chromosomal contact data.

    Science.gov (United States)

    Oluwadare, Oluwatosin; Zhang, Yuxiang; Cheng, Jianlin

    2018-02-23

    The development of chromosomal conformation capture techniques, particularly, the Hi-C technique, has made the analysis and study of the spatial conformation of a genome an important topic in bioinformatics and computational biology. Aided by high-throughput next generation sequencing techniques, the Hi-C technique can generate genome-wide, large-scale intra- and inter-chromosomal interaction data capable of describing in details the spatial interactions within a genome. These data can be used to reconstruct 3D structures of chromosomes that can be used to study DNA replication, gene regulation, genome interaction, genome folding, and genome function. Here, we introduce a maximum likelihood algorithm called 3DMax to construct the 3D structure of a chromosome from Hi-C data. 3DMax employs a maximum likelihood approach to infer the 3D structures of a chromosome, while automatically re-estimating the conversion factor (α) for converting Interaction Frequency (IF) to distance. Our results show that the models generated by 3DMax from a simulated Hi-C dataset match the true models better than most of the existing methods. 3DMax is more robust to structural variability and noise. Compared on a real Hi-C dataset, 3DMax constructs chromosomal models that fit the data better than most methods, and it is faster than all other methods. The models reconstructed by 3DMax were consistent with fluorescent in situ hybridization (FISH) experiments and existing knowledge about the organization of human chromosomes, such as chromosome compartmentalization. 3DMax is an effective approach to reconstructing 3D chromosomal models. The results, and the models generated for the simulated and real Hi-C datasets are available here: http://sysbio.rnet.missouri.edu/bdm_download/3DMax/ . The source code is available here: https://github.com/BDM-Lab/3DMax . A short video demonstrating how to use 3DMax can be found here: https://youtu.be/ehQUFWoHwfo .

  5. Neocentromeres Provide Chromosome Segregation Accuracy and Centromere Clustering to Multiple Loci along a Candida albicans Chromosome.

    Directory of Open Access Journals (Sweden)

    Laura S Burrack

    2016-09-01

    Full Text Available Assembly of kinetochore complexes, involving greater than one hundred proteins, is essential for chromosome segregation and genome stability. Neocentromeres, or new centromeres, occur when kinetochores assemble de novo, at DNA loci not previously associated with kinetochore proteins, and they restore chromosome segregation to chromosomes lacking a functional centromere. Neocentromeres have been observed in a number of diseases and may play an evolutionary role in adaptation or speciation. However, the consequences of neocentromere formation on chromosome missegregation rates, gene expression, and three-dimensional (3D nuclear structure are not well understood. Here, we used Candida albicans, an organism with small, epigenetically-inherited centromeres, as a model system to study the functions of twenty different neocentromere loci along a single chromosome, chromosome 5. Comparison of neocentromere properties relative to native centromere functions revealed that all twenty neocentromeres mediated chromosome segregation, albeit to different degrees. Some neocentromeres also caused reduced levels of transcription from genes found within the neocentromere region. Furthermore, like native centromeres, neocentromeres clustered in 3D with active/functional centromeres, indicating that formation of a new centromere mediates the reorganization of 3D nuclear architecture. This demonstrates that centromere clustering depends on epigenetically defined function and not on the primary DNA sequence, and that neocentromere function is independent of its distance from the native centromere position. Together, the results show that a neocentromere can form at many loci along a chromosome and can support the assembly of a functional kinetochore that exhibits native centromere functions including chromosome segregation accuracy and centromere clustering within the nucleus.

  6. Female chromosome X mosaicism is age-related and preferentially affects the inactivated X chromosome

    OpenAIRE

    Machiela, MJ; Zhou, W; Karlins, E. (Eric); Sampson, JN; Freedman, ND; Yang, Q.; Hicks, B.; Dagnall, C; Hautman, C; Jacobs, KB; Abnet, CC; Aldrich, MC; Amos, C; Amundadottir, LT; Arslan, AA

    2016-01-01

    To investigate large structural clonal mosaicism of chromosome X, we analysed the SNP microarray intensity data of 38,303 women from cancer genome-wide association studies (20,878 cases and 17,425 controls) and detected 124 mosaic X events >2 Mb in 97 (0.25%) women. Here we show rates for X-chromosome mosaicism are four times higher than mean autosomal rates; X mosaic events more often include the entire chromosome and participants with X events more likely harbour autosomal mosaic events....

  7. Neo-sex chromosome inheritance across species in Silene hybrids.

    Science.gov (United States)

    Weingartner, L A; Delph, L F

    2014-07-01

    Neo-sex chromosomes, which form through the major restructuring of ancestral sex chromosome systems, have evolved in various taxa. Such restructuring often consists of the fusion of an autosome to an existing sex chromosome, resulting in novel sex chromosome formations (e.g. X1X2Y or XY1Y2.). Comparative studies are often made between restructured sex chromosome systems of closely related species, and here we evaluate the consequences of variable sex chromosome systems to hybrids. If neo-sex chromosomes are improperly inherited across species, this could lead to aberrant development and reproductive isolation. In this study, we examine the fate of neo-sex chromosomes in hybrids of the flowering plants Silene diclinis and Silene latifolia. Silene diclinis has a neo-sex chromosome system (XY1Y2) that is thought to have evolved from an ancestral XY system that is still present in S. latifolia. These species do not hybridize naturally, and improper sex chromosome inheritance could contribute to reproductive isolation. We investigated whether this major restructuring of sex chromosomes prevents their proper inheritance in a variety of hybrid crosses, including some F2 - and later-generation hybrids, with sex chromosome-linked, species-specific, polymorphic markers and chromosome squashes. We discovered that despite the differences in sex chromosomes that exist between these two species, proper segregation had occurred in hybrids that made it to flowering, including later-generation hybrids, indicating that neo-sex chromosome formation alone does not result in complete reproductive isolation between these two species. Additionally, hybrids with aberrant sex expression (e.g. neuter, hermaphrodite) also inherited the restructured sex chromosomes properly, highlighting that issues with sexual development in hybrids can be caused by intrinsic genetic incompatibility rather than improper sex chromosome inheritance. © 2014 The Authors. Journal of Evolutionary Biology © 2014

  8. [Chromosomal mosaicism in spontaneous abortions: analysis of 650 cases].

    Science.gov (United States)

    Vorsanova, S G; Iurov, I Iu; Kolotiĭ, A D; Beresheva, A K; Demidova, I A; Kurinnaia, O S; Kravets, V S; Monakhov, V V; Solov'ev, I V; Iurov, Iu B

    2010-10-01

    It is known that up to 50% spontaneous abortions (SA) in the first trimester of pregnancy are associated with chromosomal abnormalities. We studied mosaic forms of chromosomal abnormalities in 650 SA specimens using interphase mFISH and DNAprobes for chromosomes 1,9, 13/21, 14/22, 15, 16, 18, X, and Y. Numerical chromosomal abnormalities were discovered in 58.2% (378 cases). They contained combined chromosomal abnormalities (aneuploidy of several chromosomes or aneuploidy in combination with polyploidy in the same specimen) in 7.7% (29 cases) or 4.5% of the entire SA sample; autosomal trisomy, in 45% (18.2% in chromosome 16, 8.9% in chromosomes 14/22, 7.9% in chromosomes 13/21, 3.1% in chromosome 18, and 1.4% in chromosome 9). Chromosome X aneuploidy was found in 27% cases, among which 9.6% represented chromosome X monosomy. Polyploidy was observed in 22.9% cases. In 5.1% cases, we observed mosaic form of autosomal monosomy Among the SA cases with chromosomal abnormalities mosaicism was observed in 50.3% (approximately 25% of the entire SA sample). The results of the present study indicate that significant amount of chromosomal abnormalities in SA cells are associated with disturbances in mitotic chromosome separation, which represents the most common cause of intrauterine fetal death. It was also shown that original collection of DNA probes and the technique of interphase MFISH could be useful for detection of chromosomal mosaicism in prenatal cell specimens.

  9. Dispensable chromosomes in Fusarium oxysporum f. sp. lycopersici.

    Science.gov (United States)

    Vlaardingerbroek, Ido; Beerens, Bas; Schmidt, Sarah M; Cornelissen, Ben J C; Rep, Martijn

    2016-12-01

    The genomes of many filamentous fungi consist of a 'core' part containing conserved genes essential for normal development as well as conditionally dispensable (CD) or lineage-specific (LS) chromosomes. In the plant-pathogenic fungus Fusarium oxysporum f. sp. lycopersici, one LS chromosome harbours effector genes that contribute to pathogenicity. We employed flow cytometry to select for events of spontaneous (partial) loss of either the two smallest LS chromosomes or two different core chromosomes. We determined the rate of spontaneous loss of the 'effector' LS chromosome in vitro at around 1 in 35 000 spores. In addition, a viable strain was obtained lacking chromosome 12, which is considered to be a part of the core genome. We also isolated strains carrying approximately 1-Mb deletions in the LS chromosomes and in the dispensable core chromosome. The large core chromosome 1 was never observed to sustain deletions over 200 kb. Whole-genome sequencing revealed that some of the sites at which the deletions occurred were the same in several independent strains obtained for the two chromosomes tested, indicating the existence of deletion hotspots. For the core chromosome, this deletion hotspot was the site of insertion of the marker used to select for loss events. Loss of the core chromosome did not affect pathogenicity, whereas loss of the effector chromosome led to a complete loss of pathogenicity. © 2016 THE AUTHORS. MOLECULAR PLANT PATHOLOGY PUBLISHED BY BRITISH SOCIETY FOR PLANT PATHOLOGY AND JOHN WILEY & SONS LTD.

  10. RESEARCH ARTICLE Y chromosome polymorphisms of the ...

    Indian Academy of Sciences (India)

    2017-02-10

    Feb 10, 2017 ... individual camels. In addition, a TG repeat in the USP9Y gene was identified as the first polymorphic microsatellite in the camel Y chromosome, whereas microsatellites based on bovine sequences were not detected. The frequency of each allele varied among different populations.For the Nanjiang, Hexi ...

  11. Monosomic analysis reveals duplicated chromosomal segments in ...

    Indian Academy of Sciences (India)

    g bg. GGg or. Golden plant. –. bGg, GGGg. –, Indicates the absence of dominant allele (due to nondisjunction of chromosome carrying dominant allele) in the egg cell (female gamete) and consequently creating hemizygous condition in the embryos of monosomic plants. Journal of Genetics, Vol. 88, No. 3, December 2009.

  12. MORPHOLOGY AND CHROMOSOME NUMBERS OF Gongronema ...

    African Journals Online (AJOL)

    journal

    Morphology and chromosome numbers than one nucleus per cell (Partanen, 1963). Polyploidy in some instances is advantageous as it affects plant part sizes like larger leaf areas, flowers and fruits (Walker et al. 2005; El-. Ferchichi et al. 2006; Samiha et al. 2009). The higher number of viable seeds per follicle and matured ...

  13. Turner Syndrome: Phenotypic Variability of Chromosomal Polymorphism

    Directory of Open Access Journals (Sweden)

    M.O. Ryznychuk

    2015-07-01

    Full Text Available Turner syndrome was firstly described by N. Shereshevskyi in 1925, and then by H. Turner in 1938. In 1959, Ch. Ford found that in patients with this syndrome one X chromosome is absent. The cause of this is that in the process of fertilization, one of two X chromosomes of maternal egg or paternal sperm is lost. Recent studies have suggested that two-thirds of patients with Turner syndrome do not have one X chromosome. Patients are almost exclusively women. Their karyotype is 45, X. Among newborn girls, Turner syndrome occurs with a frequency of 1 : 3,000, and among girls suffering from mental retardation — 1 : 1,500. The decisive arguments in the diagnosis of Turner syndrome are typical clinical features; data of study of sex chromatin and karyotype; possible prenatal diagnosis of fetal pathology. Patients with Turner syndrome require hormone therapy (by growth hormone, sex hormones, correction of congenital malformations and aesthetic defects. This article summarizes data of features of phenotypic manifestations of Turner syndrome, depending on the variant of chromosomal abnormalities.

  14. Chromosomal evolution and phylogenetic analyses in Tayassu ...

    Indian Academy of Sciences (India)

    (SFRH/BSAB/329/2003) sabbatical grants. References. Adega F., Chaves R. and Guedes-Pinto H. 2005 Chromosome re- striction enzyme digestion in domestic pig (Sus scrofa). Consti- tutive heterochromatin arrangement. Genes Genet. Sys. 80, 49–. 56. Adega F., Chaves R., Kofler A., Krausman P. R., Masabanda J.,.

  15. Insect chromosomes preparing methods for genetic researches ...

    African Journals Online (AJOL)

    Cytogenetics are almost always based on the examination of the fixed mitotic chromosomes during the analyses of metaphase. During this phase of the cycle of cells, the DNA is folded up and chromatin is strongly condensed. The relative position of the centromere is constant, which means that the ratio of the lengths of the ...

  16. Evaluation of Chromosomal Abnormalities and Common ...

    African Journals Online (AJOL)

    Its' pathophysiology is poorly understood. Infections, genetic, endocrine, anatomic and immunologic problems have been suggested as causes for RM. Objective: To evaluate the frequency of chromosomal abnormalities and 3 common thrombophilic mutations in couples with RM. Methods: A retrospective data collection ...

  17. Association of recurrent pregnancy loss with chromosomal ...

    African Journals Online (AJOL)

    EB

    Zhonghua Yi Xue Yi. Chuan Xue Za Zhi. 2011; 28: 575-8. 18. Kwinecka-Dmitriew B, Zakrzewska M, Latos-. Bieleñska A, Skrzypczak J. Frequency of chromosomal aberrations in material from abortions. Ginekol Pol 2010; 81: 896-901. 19. Be C, Velásquez P, Youlton R. Spontaneous abortion: cytogenetic study of 609 cases.

  18. New molecular techniques for chromosome analysis.

    Science.gov (United States)

    Pergament, E

    2000-08-01

    The advent of molecular genetic technology has significantly advanced knowledge about the structure of chromosomes and their behaviour during meiosis and mitosis, as well as delineating cytogenetic aberrations that cannot be identified by conventional chromosome analysis. Molecular cytogenetics, the visualization of genetic loci using the dynamic recombinant technology of fluorescence in situ hybridization (FISH), now provides the obstetrician and gynaecologist with increasingly important diagnostic and prognostic information heretofore unavailable. The technical principles underlying FISH are briefly discussed. Emphasis is placed on the clinical applications of FISH and technologies derived from FISH, in particular comparative genome hybridization, microdissection FISH and multiplex FISH. These technologies play increasingly significant roles in preimplantation and prenatal genetic diagnosis, in the identification of microdeletion syndromes, cryptic translocations and marker chromosomes, and in defining chromosome mosaicism. FISH and related technologies also constitute essential diagnostic modalities in follow-up of organ transplantation, in a variety of haematological disorders and in determining the amplification of oncogenes associated with specific forms of cancer and neoplasia. Copyright 2000 Harcourt Publishers Ltd.

  19. Fetal chromosome abnormalities and congenital malformations: an ...

    African Journals Online (AJOL)

    Objective: Our objective were to determine and evaluate the role of genetic counseling and amniocentesis in early detection of chromosomal abnormalities or congenital malformations among women at risk. Patients and Methods: The study was performed on 784 pregnant women. Results: The cause for seeking genetic ...

  20. Nondisjunction of chromosome 15: Origin and recombination

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, W.P.; Bernasconi, F.; Schinzel, A.A.; Mutirangura, A.; Ledbetter, D.H. (Baylor College of Medicine, Houston, TX (United States)); Langlois, S. (Univ. of Britisch Columbia, Vancouver (Canada)); Morris, M.A.; Malcolm, S.

    1993-09-01

    Thirty-two cases of uniparental disomy (UPD), ascertained from Prader-Willi syndrome patients (N=27) and Angelman syndrome patients (N-5), are used to investigate the pattern of recombination associated with nondisjunction of chromosome 15. In addition, the meiotic stage of nondisjunction is inferred by using markers mapping near the centromere. Two basic approaches to the analysis of recombination in specific pairwise intervals along the chromosome. This method shows a significant reduction in recombination for two of five intervals examined. Second, the observed frequency of each recombinant class (i.e., zero, one, two, three, or more observable crossovers) is compared with expected values. This is useful for testing whether the reduction in recombination can be attributed solely to a proportion of cases with no recombination at all (because of asynapsis), with the remaining groups showing normal recombination (or even excess recombination), or whether recombination is uniformly reduced. Analysis of maternal UPD(15) data shows a slight reduction in the multiple-recombinant classes, with a corresponding increase in both the zero- and one-recombinant classes over expected values. The majority, more than 82%, of the extra chromosomes in maternal UPD(15) cases are due to meiotic I nondisjunction events. In contrast, more paternal UPD(15) cases so far examined appear to have a postzygotic origin of the extra paternal chromosome. 33 refs., 1 fig., 7 tabs.

  1. The chromosome 9q subtelomere deletion syndrome

    NARCIS (Netherlands)

    Stewart, D.R.; Kleefstra, T.

    2007-01-01

    The chromosome 9q subtelomere deletion syndrome (9qSTDS) is among the first and most common clinically recognizable syndromes to arise from widespread testing by fluorescent in situ hybridization (FISH) of subtelomere deletions. There are about 50 reported cases worldwide. Affected individuals

  2. Chromosomal evolution and phylogenetic analyses in Tayassu ...

    Indian Academy of Sciences (India)

    The mammalian family Tayassuidae (peccaries) is confined to the New World and comprises three recognized extant species, white-lipped (Tayassu pecari), collared (Pecari tajacu) and chacoan (Catagonus wagneri) peccaries, which exhibit distinct morphological and chromosomal features. The phylogenetic relationships ...

  3. Chromosomal aberrations induced by Markhamia tomentosa (Benth ...

    African Journals Online (AJOL)

    Markhamia tomentosa (Benth.) K. Schum. Ex Engl. (Bignoniaceae) is used traditionally in the treatment of pain, oedema, pulmonary troubles and cancer. The genotoxic and cytotoxic effects of the ethanolic extract of the leaves of M. tomentosa was investigated using the Allium cepa root chromosomal aberration assay.

  4. Frequency of congenital malformations and chromosomal disorders ...

    Indian Academy of Sciences (India)

    The main congenital disorders observed were: cardiovascular system anomalies, musculoskeletal system, urogenital system, etc. During the investigation period, in the human population of Bacau county, 97 cases of newborns with chromosomal disorders were diagnosed (0.16% of the living newborns), while in Vaslui ...

  5. First trimester ultrasound screening of chromosomal abnormalities

    Directory of Open Access Journals (Sweden)

    Trninić-Pjević Aleksandra

    2007-01-01

    Full Text Available Introduction: A retrocervical subcutaneous collection of fluid at 11-14 weeks of gestation, can be visualized by ultrasound as nuchal translucency (NT. Objective. To examine the distribution of fetal nuchal translucency in low risk population, to determine the detection rate of chromosomal abnormalities in the population of interest based on maternal age and NT measurement. Method. Screening for chromosomal defects, advocated by The Fetal Medicine Foundation (FMF, was performed in 1,341 pregnancies in the period January 2000 - April 2004. Initial risk for chromosomal defects (based on maternal and gestational age and corrected risk, after the NT measurement, were calculated. Complete data were collected from 1,048 patients. Results. Out of 1,048 pregnancies followed, 8 cases of Down’s syndrome were observed, 7 were detected antenatally and 6 out of 7 were detected due to screening that combines maternal age and NT measurement. According to our results, sensitivity of the screening for aneuploidies based on maternal age alone was 12.5% and false positive rate 13.1%, showing that screening based on NT measurement is of great importance. Screening by a combination of maternal age and NT, and selecting a screening-positive group for invasive testing enabled detection of 75% of fetuses with trisomy 21. Conclusion. In screening for chromosomal abnormalities, an approach which combines maternal age and NT is effective and increases the detection rate compared to the use of any single test. .

  6. Taurodontism in females with extra X chromosomes.

    Science.gov (United States)

    Varrela, J; Alvesalo, L

    1989-01-01

    The association between taurodontism and extra X chromosomes was studied in four 47,XXX-females and in two 48,XXXX-females. Occurrence of the trait in the permanent mandibular molars was noted from orthopantomograms. Five first-degree relatives and a sample of 157 normal males and females were investigated as controls. Two of the 47,XXX-females and both 48,XXX-females each had at least one mandibular molar classified as taurodont. The two affected 47,XXX-females had hypotaurodont or mesotaurodont teeth, whereas both 48,XXXX-females showed hypertaurodontism. The manidubular molars of the other two 47,XXX females had normal root morphology. The only control relative with taurodont teeth was a sister to a 48,XXXX-female. In the population control group, four females had taurodont teeth. These results support the concept that a prevalence of taurodontism increases as the number of X chromosomes increases and also indicate that expression of the trait and the number of X chromosomes may be positively correlated. It is suggested that the X chromosome gene(s) influencing development of enamel may be involved in the development of taurodontism.

  7. Improved prenatal detection of chromosomal anomalies

    DEFF Research Database (Denmark)

    Frøslev-Friis, Christina; Hjort-Pedersen, Karina; Henriques, Carsten U

    2011-01-01

    Prenatal screening for karyotype anomalies takes place in most European countries. In Denmark, the screening method was changed in 2005. The aim of this study was to study the trends in prevalence and prenatal detection rates of chromosome anomalies and Down syndrome (DS) over a 22-year period....

  8. Association of recurrent pregnancy loss with chromosomal ...

    African Journals Online (AJOL)

    Objective: To evaluate the association of parental and fetal chromosomal abnormalities with recurrent pregnancy loss in our area and to analyze the frequency of three types of hereditary thrombophilia's; (MTHFR C677T polymorphisms, FV Leiden G1691A mutation and Prothrombin (factor II) G20210A mutation) in these ...

  9. MORPHOLOGY AND CHROMOSOME NUMBERS OF Gongronema ...

    African Journals Online (AJOL)

    journal

    Cytological studies on the root-tips of four clones of Gongronema latifolia Benth. were conducted to identify cross-compatible clones for possible improvement through hybridisation. The results showed that the diploid chromosomes number in G. latifolia was 2n = 16. Clones, IMS-20-NJIABA, AKS-33-EKPENE EDIENE, ANS-.

  10. Morphology and chromosome numbers of Gongronema latifolia ...

    African Journals Online (AJOL)

    Cytological studies on the root-tips of four clones of Gongronema latifolia Benth. were conducted to identify cross-compatible clones for possible improvement through hybridisation. The results showed that the diploid chromosomes number in G. latifolia was 2n = 16. Clones, IMS-20-NJIABA, AKS-33-EKPENE EDIENE, ...

  11. Chromosome Conformation Capture on Chip (4C)

    DEFF Research Database (Denmark)

    Leblanc, Benjamin Olivier; Comet, Itys; Bantignies, Frédéric

    2016-01-01

    4C methods are useful to investigate dependencies between regulatory mechanisms and chromatin structures by revealing the frequency of chromatin contacts between a locus of interest and remote sequences on the chromosome. In this chapter we describe a protocol for the data analysis of microarray...

  12. Monosomic analysis reveals duplicated chromosomal segments in ...

    Indian Academy of Sciences (India)

    Monosomics for chromosome 2 expressed liguleless leaf phenotype due to hemizygous condition of recessive gene lg. Two monosomic-4 plants were identified after test crossing with monosomic tester (see table 2 in electronic supplemen- tary material). Monosomic-6 plants were identified by the cytological analysis (figure ...

  13. Ring Chromosome 7 in an Indian Woman

    Science.gov (United States)

    Kaur, Anupam; Dhillon, Sumit; Garg, P. D.; Singh, Jai Rup

    2008-01-01

    Background: Ring chromosome 7 [r(7)] is a rare cytogenetic aberration, with only 16 cases (including 3 females) reported in the literature to date. This is the first reported case of r(7) from India. Method: Clinical and cytogenetic investigations were carried out in an adult female with microcephaly and intellectual disability. Results: Ring…

  14. Mitotic chromosome compaction via active loop extrusion

    Science.gov (United States)

    Goloborodko, Anton; Imakaev, Maxim; Marko, John; Mirny, Leonid; MIT-Northwestern Team

    During cell division, two copies of each chromosome are segregated from each other and compacted more than hundred-fold into the canonical X-shaped structures. According to earlier microscopic observations and the recent Hi-C study, chromosomes are compacted into arrays of consecutive loops of ~100 kilobases. Mechanisms that lead to formation of such loop arrays are largely unknown. Here we propose that, during cell division, chromosomes can be compacted by enzymes that extrude loops on chromatin fibers. First, we use computer simulations and analytical modeling to show that a system of loop-extruding enzymes on a chromatin fiber self-organizes into an array of consecutive dynamic loops. Second, we model the process of loop extrusion in 3D and show that, coupled with the topo II strand-passing activity, it leads to robust compaction and segregation of sister chromatids. This mechanism of chromosomal condensation and segregation does not require additional proteins or specific DNA markup and is robust against variations in the number and properties of such loop extruding enzymes. Work at NU was supported by the NSF through Grants DMR-1206868 and MCB-1022117, and by the NIH through Grants GM105847 and CA193419. Work at MIT was supported by the NIH through Grants GM114190 R01HG003143.

  15. Chromosomes and plant cell division in space

    Science.gov (United States)

    Krikorian, A. D.

    1988-01-01

    The objectives were: examination of chromosomal aberrations; development of an experimental system; and engineering design units (EDUs) evaluation. Evaluation criteria are presented. Procedures were developed for shuttle-based investigations which result in the procurement of plant root tips for subsequent cytological examination.

  16. Transcript variations, phylogenetic tree and chromosomal ...

    Indian Academy of Sciences (India)

    Transcript variations, phylogenetic tree and chromosomal localization of porcine aryl hydrocarbon receptor (AhR) and AhR nuclear translocator (ARNT) genes ... Prawochenskiego 5, 10-720 Olsztyn, Poland; Department of Genetics and Animal Breeding, Poznan University of Life Science, Wolynska 33, 60-637 Poznan, ...

  17. Human oocyte chromosome analyses need a standardized ...

    Indian Academy of Sciences (India)

    Studies of DNA polymorphisms in human trisomic abor- tions and liveborn have revealed a chromosome-specific vari- ation in the importance of meiosis I versus meiosis II er- rors. As a general rule, maternal meiosis I errors predom- inate among almost all trisomies (Hassold and Hunt 2001). It is evident that a direct ...

  18. Insect chromosomes preparing methods for genetic researches

    African Journals Online (AJOL)

    STORAGESEVER

    2009-01-05

    Jan 5, 2009 ... Importantly, each chromosome displays a unique banding pattern. Different staining methods showed the banding pattern (g band), ... with 100 t/mn in a clinical centrifugal machine, with sodium citrate for 1 - 10 min, fixed and dried as described above. Measurement of length are taken on photographs.

  19. Insect chromosomes preparing methods for genetic researches

    African Journals Online (AJOL)

    STORAGESEVER

    2009-01-05

    Jan 5, 2009 ... Cytogenetics are almost always based on the examination of the fixed mitotic chromosomes during the analyses of metaphase. During this phase of the cycle of cells, the DNA is folded up and chromatin is strongly condensed. The relative position of the centromere is constant, which means that the ratio of.

  20. The chromosome number of Anthocleista djalonensis Chev

    NARCIS (Netherlands)

    Gadella, T.W.J.

    1961-01-01

    Few cytological data are available of the Loganiaceae. Its subfamily Buddleioideae, often considered a separate family, is a well-defined group, as far as could be concluded from the chromosome number. On the other hand, nothing can be said with certainty of the other subfamily, the Loganioideae,

  1. Histone modifications: Cycling with chromosomal replication

    DEFF Research Database (Denmark)

    Thon, Genevieve

    2008-01-01

    Histone modifications tend to be lost during chromosome duplication. Several recent studies suggest that the RNA interference pathway becomes active during the weakened transcriptional repression occurring at centromeres in S phase, resulting in the re-establishment of histone modifications that ...

  2. Understanding Chromosome Disorders and their Implications for Special Educators

    Directory of Open Access Journals (Sweden)

    Linda Gilmore

    2014-03-01

    Full Text Available More children are now being diagnosed with chromosome abnormalities. Some chromosome disorder syndromes are relatively well known; while others are so rare that there is only limited evidence about their likely impact on learning and development. For educators, a basic level of knowledge about chromosome abnormalities is important for understanding the literature and communicating with families and professionals. This paper describes chromosomes, and the numerical and structural anomalies that can occur, usually spontaneously during early cell division. Distinctive features of various chromosome syndromes are summarised before a discussion of the rare chromosome disorders that are labelled, not with a syndrome name, but simply by a description of the chromosome number, size and shape. Because of the potential within-group variability that characterises syndromes, and the scarcity of literature about the rare chromosome disorders, expectations for learning and development of individual students need to be based on the range of possible outcomes that may be achievable.

  3. Sperm chromosomal abnormalities in patients with unexplained recurrent abortions.

    Science.gov (United States)

    Al-Hassan, S; Hellani, A; Al-Shahrani, A; Al-Deery, M; Jaroudi, K; Coskun, S

    2005-01-01

    Cytogenetic studies showed that about half of concepti were chromosomally abnormal in first trimester abortions. Sperm chromosomal abnormalities in men with normal karyotype could occur during spermatogenesis. The objective of this study was to evaluate sperm chromosomal abnormalities in patients with unexplained recurrent abortions. A total of 14 couples with normal karyotype, and negative workup for endocrine, immune and anatomical causes of recurrent abortion was investigated. Semen analysis was performed and chromosomal abnormalities were assessed by fluorescent in situ hybridization for chromosomes 13, 18, 21, X and Y. The average number of abortions was 5.8. The incidence of chromosomal abnormalities was 16.5% that was higher when compared to baseline (4.6%). In conclusion, a high rate of sperm chromosomal abnormalities was observed in recurrent abortion patients. These abnormalities might form during spermatogenesis since all patients had normal karyotype. Sperm chromosomal abnormality analysis can be included into recurrent abortion workup when no other cause is detected.

  4. Mapping and ordered cloning of the human X chromosome

    Energy Technology Data Exchange (ETDEWEB)

    Caskey, C.T.; Nelson, D.L.

    1992-12-01

    Progress is reported on gathering X chromosome specific libraries and integrating those with the library produced in this project. Further studies on understanding Fragile X Syndrome and other hereditary diseases related to the X chromosome are described. (DT)

  5. Flow cytometry measurements of human chromosome kinetochore labeling

    Energy Technology Data Exchange (ETDEWEB)

    Fantes, J.A.; Green, D.K.; Malloy, P.; Sumner, A.T.

    1989-03-01

    A method for the preparation and measurement of immunofluorescent human chromosome centromeres in suspension is described using CREST antibodies, which bind to the centromeric region of chromosomes. Fluorescein isothiocyanate (FITC)-conjugated antihuman antibodies provide the fluorescent label. Labeled chromosomes are examined on microscope slides and by flow cytometry. In both cases a dye which binds to DNA is added to provide identification of the chromosome groups. Sera from different CREST patients vary in their ability to bind to chromosome arms in addition to the centromeric region. Flow cytometry and microfluorimetry measurements have shown that with a given CREST serum the differences in kinetochore fluorescence between chromosomes are only minor. Flow cytometry experiments to relate the number of dicentric chromosomes, induced by in vitro radiation of peripheral blood cells to the slightly increased number of chromosomes with above-average kinetochore fluorescence did not produce decisive radiation dosimetry results.

  6. Use of chromosome microdissection in fish molecular cytogenetics

    Directory of Open Access Journals (Sweden)

    Frederico Henning

    2008-01-01

    Full Text Available Chromosome microdissection is a technique in which whole chromosomes or chromosomal segments are dissected under an inverted microscope yielding chromosome-specific sequences. Several protocol modifications introduced during the past 15 years reduced the number of chromosomes required for most applications. This is of particular interest to fish molecular cytogenetics, since most species present highly uniform karyotypes which make impossible the collection of multiple copies of the same chromosome. Probes developed in this manner can be used to investigate chromosome homologies in closely related species. Here we describe a protocol recently used in the gymnotiform species group Eigenmannia and review the major steps involved in the generation of these markers focusing on protocol modifications aiming to reduce the number of required chromosomes.

  7. Dosage compensation, the origin and the afterlife of sex chromosomes.

    Science.gov (United States)

    Larsson, Jan; Meller, Victoria H

    2006-01-01

    Over the past 100 years Drosophila has been developed into an outstanding model system for the study of evolutionary processes. A fascinating aspect of evolution is the differentiation of sex chromosomes. Organisms with highly differentiated sex chromosomes, such as the mammalian X and Y, must compensate for the imbalance in gene dosage that this creates. The need to adjust the expression of sex-linked genes is a potent force driving the rise of regulatory mechanisms that act on an entire chromosome. This review will contrast the process of dosage compensation in Drosophila with the divergent strategies adopted by other model organisms. While the machinery of sex chromosome compensation is different in each instance, all share the ability to direct chromatin modifications to an entire chromosome. This review will also explore the idea that chromosome-targeting systems are sometimes adapted for other purposes. This appears the likely source of a chromosome-wide targeting system displayed by the Drosophila fourth chromosome.

  8. Angular resolved light scattering microscopy on human chromosomes

    Science.gov (United States)

    Müller, Dennis; Stark, Julian; Kienle, Alwin

    2017-07-01

    Angular resolved scattering light measurements on chromosomes are compared to Discrete Dipole Approximation (DDA) simulations using Atomic Force Microscopy (AFM) based geometrical models. This could present a novel, marker-free method for human chromosome karyotyping.

  9. Identification of Chromosomes Alterations in Primary Breast Cancer Using Premature Chromosome Condensation

    National Research Council Canada - National Science Library

    Griffin, Constance

    2000-01-01

    .... We are developing a new method, premature chromosome condensation (PCC),using mitotic Xenopus extracts that will allow us to obtain G-banded karyotypes from primary, uncultured breast cancer specimens...

  10. Neo-sex chromosomes in the black muntjac recapitulate incipient evolution of mammalian sex chromosomes

    DEFF Research Database (Denmark)

    Zhou, Qi; Wang, Jun; Huang, Ling

    2008-01-01

    muntjac, in which a recent X-autosome fusion and a subsequent large autosomal inversion within just the past 0.5 million years have led to inheritance patterns identical to the traditional X-Y (neo-sex chromosomes). We compared patterns of genome evolution in 35-kilobase noncoding regions and 23 gene......BACKGROUND: The regular mammalian X and Y chromosomes diverged from each other at least 166 to 148 million years ago, leaving few traces of their early evolution, including degeneration of the Y chromosome and evolution of dosage compensation. RESULTS: We studied the intriguing case of black...... pairs on the homologous neo-sex chromosomes. We found that neo-Y alleles have accumulated more mutations, comprising a wide variety of mutation types, which indicates cessation of recombination and is consistent with an ongoing neo-Y degeneration process. Putative deleterious mutations were observed...

  11. Insertion of retrotransposons at chromosome ends: adaptive response to chromosome maintenance

    Directory of Open Access Journals (Sweden)

    Geraldine eServant

    2016-01-01

    Full Text Available The telomerase complex is a specialized reverse transcriptase that inserts tandem DNA arrays at the linear chromosome ends and contributes to the protection of the genetic information in eukaryotic genomes. Telomerases are phylogenetically related to retrotransposons, encoding also the reverse transcriptase activity required for the amplification of their sequences throughout the genome. Intriguingly the telomerase gene is lost from the drosophila genome and tandem retrotransposons replace telomeric sequences at the chromosome extremities. This observation suggests the versatility of reverse transcriptase activity in counteracting the chromosome shortening associated with genome replication and that retrotransposons can provide this activity in case of a dysfunctional telomerase. In this review paper, we describe the major classes of retroelements present in eukaryotic genomes in order to point out the differences and similarities with the telomerase complex. In a second part, we discuss the insertion of retroelements at the ends of chromosomes as an adaptive response for dysfunctional telomeres.

  12. Metagenomic chromosome conformation capture (meta3C) unveils the diversity of chromosome organization in microorganisms

    National Research Council Canada - National Science Library

    Marbouty, Martial; Cournac, Axel; Flot, Jean-François; Marie-Nelly, Hervé; Mozziconacci, Julien; Koszul, Romain

    2014-01-01

    .... Consequently, the chromosome organization of microorganisms has been investigated in a few model species, but the extent to which the features described can be generalized to other taxa remains unknown...

  13. Chromosomes of South American Bufonidae (Amphibia, Anura Chromosomes of South American Bufonidae (Amphibia, Anura

    Directory of Open Access Journals (Sweden)

    Brum Zorrilla N.

    1973-09-01

    Full Text Available Karyotypes of eight of South American Bufonidae were studied: B.ictericus, B. spinulosus spinulosus, B. arenarum, B. g. fernandezae, B. g. d'orbignyi, B. crucifer, B. paracnemis and B. marinus. In all species 2n = 22 chromosomes were found. Neither heteromorphic pairs of chromosomes nor bivalents with characteristic morphology and behavior of sex chromosomesduring male meiosis were observed in any species.Karyotypes of eight of South American Bufonidae were studied: B.ictericus, B. spinulosus spinulosus, B. arenarum, B. g. fernandezae, B. g. d'orbignyi, B. crucifer, B. paracnemis and B. marinus. In all species 2n = 22 chromosomes were found. Neither heteromorphic pairs of chromosomes nor bivalents with characteristic morphology and behavior of sex chromosomesduring male meiosis were observed in any species.

  14. Dielectrophoretic manipulation of human chromosomes in microfluidic channels: extracting chromosome dielectric properties

    DEFF Research Database (Denmark)

    Clausen, Casper Hyttel; Dimaki, Maria; Buckley, Sonia

    2011-01-01

    An investigation of the dielectric properties of polyamine buffer prepared human chromosomes is presented in this paper. Chromosomes prepared in this buffer are only a few micrometers in size and shaped roughly like spherical discs. Dielectrophoresis was therefore chosen as the method...... of manipulation combined with a custom designed microfluidic system containing the required electrodes for dielectrophoresis experiments. Our results show that although this system is presently not able to distinguish between the different chromosomes, it can provide average data for the dielectric properties...... of human chromosomes in polyamine buffer. These can then be used to optimize system designs for further characterization and even sorting. The experimental data from the dielectrophoretic manipulation were combined with theoretical calculations to extract a range of values for the permittivity...

  15. Chromosomes as well as chromosomal subdomains constitute distinct units in interphase nuclei

    NARCIS (Netherlands)

    Visser, A. E.; Aten, J. A.

    1999-01-01

    Fluorescence in situ hybridization has demonstrated that chromosomes form individual territories in interphase nuclei. However, this technique is not suitable to determine whether territories are mutually exclusive or interwoven. This notion, however, is essential for understanding functional

  16. Chromosomal Abnormalities Associated with Neural Tube Defects (I): Full Aneuploidy

    OpenAIRE

    Chih-Ping Chen

    2007-01-01

    Fetuses with neural tube defects (NTDs) carry a risk of chromosomal abnormalities. The risk varies with maternal age, gestational age at diagnosis, association with other structural abnormalities, and family history of chromosome aberrations. This article provides an overview of chromosomal abnormalities associated with NTDs in embryos, fetuses, and newborn patients, and a comprehensive review of numerical chromosomal abnormalities associated with NTDs, such as trisomy 18, trisomy 13, triploi...

  17. Updating the maize karyotype by chromosome DNA sizing.

    Directory of Open Access Journals (Sweden)

    Jéssica Coutinho Silva

    Full Text Available The karyotype is a basic concept regarding the genome, fundamentally described by the number and morphological features of all chromosomes. Chromosome class, centromeric index, intra- and interchromosomal asymmetry index, and constriction localization are important in clinical, systematic and evolutionary approaches. In spite of the advances in karyotype characterization made over the last years, new data about the chromosomes can be generated from quantitative methods, such as image cytometry. Therefore, using Zea mays L., this study aimed to update the species' karyotype by supplementing information on chromosome DNA sizing. After adjustment of the procedures, chromosome morphometry and class as well as knob localization enabled describing the Z. mays karyotype. In addition, applying image cytometry, DNA sizing was unprecedentedly measured for the arms and satellite of all chromosomes. This way, unambiguous identification of the chromosome pairs, and hence the assembly of 51 karyograms, were only possible after the DNA sizing of each chromosome, their arms and satellite portions. These accurate, quantitative and reproducible data also enabled determining the distribution and variation of DNA content in each chromosome. From this, a correlation between DNA amount and total chromosome length evidenced that the mean DNA content of chromosome 9 was higher than that of chromosome 8. The chromosomal DNA sizing updated the Z. mays karyotype, providing insights into its dynamic genome with regards to the organization of the ten chromosomes and their respective portions. Considering the results and the relevance of cytogenetics in the current scenario of comparative sequencing and genomics, chromosomal DNA sizing should be incorporated as an additional parameter for karyotype definition. Based on this study, it can be affirmed that cytogenetic approaches go beyond the simple morphological description of chromosomes.

  18. Variability of chromosome number and morphology and gymnosperm improvement

    OpenAIRE

    Tucović Aleksandar; Šijačić-Nikolić Mirjana; Vilotić Dragica

    2004-01-01

    The causes of monotypic and polytypic variability of the gymnosperm chromosome complex were studied. The development of karyogram and idiograms of the species should be applied in the aim of upgrading the breeding method and technique. The study of the chromosome variability depends on the knowledge on gene function at the level of chromosome and at the level of genome, i.e. at the supra-chromosome level.

  19. Optimization of calyculin A-induced premature chromosome condensation assay for chromosome aberration studies.

    Science.gov (United States)

    Miura, Tomisato; Blakely, William F

    2011-12-01

    Calyculin A-induced premature chromosome condensation (PCC) assay is a simple and useful method to assess structural and numerical chromosome aberrations in cells. Our hypothesis in this study is that suboptimum calyculin A induction of PCC resulting in fuzzy compactness and/or shortened length chromosomes would decrease the detection sensitivity of numerical and structural chromosome aberrations such as small PCC rings and small excess fragments. In this study, an optimization of calyculin A exposure on chromosome morphology and PCC induction frequency was investigated using a human peripheral blood lymphocyte (PBL) ex vivo irradiation ((60) Co-γ rays; ∼0.6 Gy/min; 0-30 Gy) model. Treatment with calyculin A (50 nM) for 15 and 30 min resulted in 11.3 ± 2.7 and 9.9 ± 1.6-fold increases in the frequency of G(2) /M-PCC cells with extended length chromosomes compared with the 60-min treated group over a broad dose range (0 to 20 Gy), respectively. The G(2) /M-PCC scoring index per PCC in 15- and 30-min treated groups was increased by 1.9 ± 0.2 (P = 0.001) and 1.8 ± 0.2 (P = 0.001) compared with the 60-min treated group over 0-20 Gy, respectively. The G(2) /M-PCC efficiency of 30-min treated group was highest in the three conditions (i.e., 15-, 30-, and 60-min treatment) of calyculin A exposure. Calyculin A (50 nM) treatment for 30 min before the 48-h harvest of mitogen-stimulated human PBL is optimum for the formation of suitable chromosome morphology necessary to assess structural chromosome aberrations induced by exposure to radiation using the chemical induced-PCC assay. Published 2011 Wiley Periodicals, Inc. Published 2011 Wiley Periodicals, Inc.

  20. Sex-chromosome anaphase movements in crane-fly spermatocytes are coordinated: ultraviolet microbeam irradiation of one kinetochore of one sex chromosome blocks the movements of both sex chromosomes

    Energy Technology Data Exchange (ETDEWEB)

    Swedak, J.A.M.; Forer, A.

    1987-11-01

    Sex chromosomes in crane-fly spermatocytes move polewards at anaphase after the autosomes have reached the poles. We irradiated one kinetochore of one sex chromosome using an ultraviolet microbeam. When both sex chromosomes were normally oriented, irradiation of a single kinetochore permanently blocked movement of both sex chromosomes. Irradiation of non-kinetochore chromosomal regions or of spindle fibres did not block movement, or blocked movement only temporarily. We argue that ultraviolet irradiation of one kinetochore blocks movement of both sex chromosomes because of effects on a 'signal' system. Irradiation of one kinetochore of a maloriented sex chromosome did not block motion of either sex chromosome. However, irradiation of one kinetochore of a normally oriented sex chromosome permanently blocked motion of both that sex chromosome and the maloriented sex chromosome. Thus for the signal system to allow the sex chromosomes to move to the pole each sex chromosome must have one spindle fibre to each pole.

  1. New chromosome numbers in the genus Trigonella L. ( Fabaceae ...

    African Journals Online (AJOL)

    Somatic chromosome numbers of 45 Trigonella L. (Fabaceae), collected from different localities in Turkey was examined. Chromosome numbers were determined as 2n = 14, 16, 30 and 46. B chromosome was also observed in somatic cells of some taxa (Trigonella arcuata C.A. Meyer and Trigonella procumbens (Besser) ...

  2. Chromosomal radiosensitivity of lymphocytes in South African breast ...

    African Journals Online (AJOL)

    chromosomal radiosensitivity.[5]. Measurement of chromosomal radiosensitivity has been used as an indirect measure of cancer susceptibility. The association between chromosomal radiosensitivity and cancer risk is supported by the following facts: cancer-prone disorders such as ataxia telangiectasia present with high ...

  3. Intrachanges as part of complex chromosome-type exchange aberrations

    NARCIS (Netherlands)

    Boei, JJWA; Vermeulen, S; Moser, J; Mullenders, LHF; Natarajan, AT

    2002-01-01

    The chromosome-type exchange aberrations induced by ionizing radiation during the G(0)/G(1) phase of the cell cycle are believed to be the result of illegitimate rejoining of chromosome breaks. From numerous studies using chromosome painting, it has emerged that even after a moderate dose of

  4. Neocentrics and holokinetics (holocentrics): chromosomes out of the centromeric rules.

    Science.gov (United States)

    Guerra, M; Cabral, G; Cuacos, M; González-García, M; González-Sánchez, M; Vega, J; Puertas, M J

    2010-07-01

    The centromere appears as a single constriction at mitotic metaphase in most eukaryotic chromosomes. Holokinetic chromosomes are the exception to this rule because they do not show any centromeric constrictions. Holokinetic chromosomes are usually forgotten in most reviews about centromeres, despite their presence in a number of animal and plant species. They are generally linked to very intriguing and unusual mechanisms of mitosis and meiosis. Holokinetic chromosomes differ from monocentric chromosomes not only in the extension of the kinetochore plate, but also in many other peculiar karyological features, which could be understood as the 'holokinetic syndrome' that is reviewed in detail. Together with holokinetic chromosomes we review neocentromeric activity, a similarly intriguing case of regions able to pull chromosomes towards the poles without showing the main components reported to be essential to centromeric function. A neocentromere is a chromosomal region different from the true centromere in structure, DNA sequence and location, but is able to lead chromosomes to the cell poles in special circumstances. Neocentromeres have been reported in plants and animals showing different features. Both in humans and Drosophila, neocentric activity appears in somatic cells with defective chromosomes lacking a functional centromere. In most cases in plants, neocentromeres appear in chromosomes which have normal centromeres, but are active only during meiosis. Because of examples such as spontaneous or induced neocentromeres and holokinetic chromosomes, it is becoming less surprising that different structures and DNA sequences of centromeres appear in evolution. Copyright 2010 S. Karger AG, Basel.

  5. Karyotypic Determinants of Chromosome Instability in Aneuploid Budding Yeast

    Science.gov (United States)

    Bradford, William D.; Li, Rong

    2012-01-01

    Recent studies in cancer cells and budding yeast demonstrated that aneuploidy, the state of having abnormal chromosome numbers, correlates with elevated chromosome instability (CIN), i.e. the propensity of gaining and losing chromosomes at a high frequency. Here we have investigated ploidy- and chromosome-specific determinants underlying aneuploidy-induced CIN by observing karyotype dynamics in fully isogenic aneuploid yeast strains with ploidies between 1N and 2N obtained through a random meiotic process. The aneuploid strains exhibited various levels of whole-chromosome instability (i.e. chromosome gains and losses). CIN correlates with cellular ploidy in an unexpected way: cells with a chromosomal content close to the haploid state are significantly more stable than cells displaying an apparent ploidy between 1.5 and 2N. We propose that the capacity for accurate chromosome segregation by the mitotic system does not scale continuously with an increasing number of chromosomes, but may occur via discrete steps each time a full set of chromosomes is added to the genome. On top of such general ploidy-related effect, CIN is also associated with the presence of specific aneuploid chromosomes as well as dosage imbalance between specific chromosome pairs. Our findings potentially help reconcile the divide between gene-centric versus genome-centric theories in cancer evolution. PMID:22615582

  6. 21 CFR 864.2260 - Chromosome culture kit.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Chromosome culture kit. 864.2260 Section 864.2260...) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Cell And Tissue Culture Products § 864.2260 Chromosome culture kit. (a) Identification. A chromosome culture kit is a device containing the necessary ingredients...

  7. Fish on avian lampbrush chromosomes produces higher resolution gene mapping

    NARCIS (Netherlands)

    Galkina, S.A.; Deryusheva, S.; Fillon, V.; Vignal, A.; Crooijmans, R.P.M.A.; Groenen, M.A.M.; Rodionov, A.V.; Gaginskaya, E.

    2006-01-01

    Giant lampbrush chromosomes, which are characteristic of the diplotene stage of prophase I during avian oogenesis, represent a very promising system for precise physical gene mapping. We applied 35 chicken BAC and 4 PAC clones to both mitotic metaphase chromosomes and meiotic lampbrush chromosomes

  8. DisA, a busy bee that monitors chromosome integrity.

    Science.gov (United States)

    Boye, Erik

    2006-05-19

    When nutrients are limited many prokaryotic and some eukaryotic cells tuck their chromosomes safely away in resistant spores. However, before starting the sporulation process, the prokaryote Bacillus subtilis wisely ensures that its chromosome is intact. In this issue of Cell, Bejerano-Sagie et al. (2006) describe a protein, DisA, that is responsible for the surveillance of chromosome integrity during sporulation.

  9. Nonrandom chromosome segregation in Neocurtilla (Gryllotalpa) hexadactyla: an ultrastructural study.

    Science.gov (United States)

    Kubai, D F; Wise, D

    1981-02-01

    During meiosis I in males of the mole cricket Neocurtilla (Gryllotalpa) hexadactyla, the univalent X1 chromosome and the heteromorphic X2Y chromosome pair segregate nonrandomly; the X1 and X2 chromosomes move to the same pole in anaphase. By means of ultrastructural analysis of serial sections of cells in several stages of meiosis I, metaphase of meiosis II, and mitosis, we found that the kinetochore region of two of the three nonrandomly segregating chromosomes differ from autosomal kinetochores only during meiosis I. The distinction is most pronounced at metaphase I when massive aggregates of electron-dense substance mark the kinetochores of X1 and Y chromosomes. The lateral position of the kinetochores of X1 and Y chromosomes and the association of these chromosomes with microtubules running toward both poles are also characteristic of meiosis I and further distinguish X1 and Y from the autosomes. Nonrandomly segregating chromosomes are typically positioned within the spindle so that the kinetochoric sides of the X2Y pair and the X1 chromosome are both turned toward the same interpolar spindle axis. This spatial relationship may be a result of a linkage of X1 and Y chromosomes lying in opposite half spindles via a small bundle of microtubules that runs between their unusual kinetochores. Thus, nonrandom segregation in Neocurtilla hexadactyla involves a unique modification at the kinetochores of particular chromosomes, which presumably affects the manner in which these chromosomes are integrated within the spindle.

  10. Dynamic sex chromosomes in Old World chameleons (Squamata: Chamaeleonidae).

    Science.gov (United States)

    Nielsen, S V; Banks, J L; Diaz, R E; Trainor, P A; Gamble, T

    2018-01-18

    Much of our current state of knowledge concerning sex chromosome evolution is based on a handful of 'exceptional' taxa with heteromorphic sex chromosomes. However, classifying the sex chromosome systems of additional species lacking easily identifiable, heteromorphic sex chromosomes is indispensable if we wish to fully understand the genesis, degeneration and turnover of vertebrate sex chromosomes. Squamate reptiles (lizards and snakes) are a potential model clade for studying sex chromosome evolution as they exhibit a suite of sex-determining modes yet most species lack heteromorphic sex chromosomes. Only three (of 203) chameleon species have identified sex chromosome systems (all with female heterogamety, ZZ/ZW). This study uses a recently developed method to identify sex-specific genetic markers from restriction site-associated DNA sequence (RADseq) data, which enables the identification of sex chromosome systems in species lacking heteromorphic sex chromosomes. We used RADseq and subsequent PCR validation to identify an XX/XY sex chromosome system in the veiled chameleon (Chamaeleo calyptratus), revealing a novel transition in sex chromosome systems within the Chamaeleonidae. The sex-specific genetic markers identified here will be essential in research focused on sex-specific, comparative, functional and developmental evolutionary questions, further promoting C. calyptratus' utility as an emerging model organism. © 2018 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2018 European Society For Evolutionary Biology.

  11. Typing of Y chromosome SNPs with multiplex PCR methods

    DEFF Research Database (Denmark)

    Sanchez Sanchez, Juan Jose; Børsting, Claus; Morling, Niels

    2005-01-01

    We describe a method for the simultaneous typing of Y-chromosome single nucleotide polymorphism (SNP) markers by means of multiplex polymerase chain reaction (PCR) strategies that allow the detection of 35 Y chromosome SNPs on 25 amplicons from 100 to 200 pg of chromosomal deoxyribonucleic acid...

  12. Determination of chromosomal ploidy in Agave ssp. | Lingling ...

    African Journals Online (AJOL)

    Chromosome observation is necessary to elucidate the structure, function and organization of Agave plants' genes and genomes. However, few researches about chromosome observation of Agave ssp. were done, not only because their chromosome numbers are large, but also because their ploidies are complicated.

  13. Y-Chromosome short tandem repeat, typing technology, locus ...

    African Journals Online (AJOL)

    Y-Chromosome short tandem repeat, typing technology, locus information and allele frequency in different population: A review. ... This review will highlight the importance of the Y- Chromosome as a tool for tracing human evolution and describes some details of Y-chromosomal short tandem repeat (STR) analysis. Among ...

  14. Visualization of chromosomes in the binucleate intestinal parasite Giardia lamblia.

    Science.gov (United States)

    Shen, Hai E; Cao, Lei; Li, Ji; Tian, Xi Feng; Yang, Zhi Hong; Wang, Yue; Tian, Yu Na; Lu, Si Qi

    2011-11-01

    Mitosis of Giardia lamblia is a complex and rapid event that is poorly understood at the cellular and molecular levels. Therefore, we conducted this study to determine (1) whether the two nuclei have similar or different chromosomes, (2) the number of chromosomes of G. lamblia, and (3) the morphology and karyotype of the chromosomes. Trophozoites of the C2 and WB strains of G. lamblia were grown in modified TYI-S-33 medium at 37°C. The trophozoites were collected, and sample slides were prepared for conventional light and scanning electron microscopy. Light microscopy revealed five pairs of chromosomes. The chromosomes were approximately 0.64-0.94 μm long with a short rod-like shape and were usually arranged in pairs. Scanning electron microscopy yielded similar findings, and 10 chromosomes could be seen in each nucleus. Thus, the chromosome number of G. lamblia is 2n = 10. Chromosomes in pair 1 are submetacentric chromosomes, while pairs 2-5 are telocentric chromosomes. The present study shows that G. lamblia trophozoites have typical condensed chromosomes during mitosis and contains five pairs of chromosomes. The karyogram shows good fit to the formula 2n = 10 = 2sm + 8t revealed by scanning electron microscopy.

  15. In situ hybridization to somatic chromosomes in Drosophila.

    Science.gov (United States)

    Dernburg, Abby F

    2011-09-01

    In situ hybridization was originally developed as a technique for visualizing and physically mapping specific sequences on Drosophila melanogaster polytene chromosomes. Hybridization techniques can also be used to localize sequences on smaller, diploid chromosomes, such as condensed mitotic chromosomes. Variations of the method also allow the hybridization of probes to chromosomes within intact cells and tissues, rather than to chromosomes isolated from their cellular context and flattened on slides. This article presents methods for hybridizing fluorescent probes to chromosomes in whole-mount Drosophila tissues. These methods allow the investigation of nuclear organization even at stages where chromosomes are decondensed (as in interphase) or, for other reasons, cannot be discriminated in the light microscope. Consequently, they are useful for addressing a variety of cell biological questions. In addition to enhancing our understanding of somatic chromosome organization, this experimental approach has also revealed interactions among meiotic chromosomes in Drosophila females, which spend much of meiosis in a compact ball called the karyosome. Fluorescent in situ hybridization (FISH) methods can also be used to karyotype individual nuclei using chromosome-specific markers. With appropriate fixation conditions, hybridization to chromosomal DNA can be performed in conjunction with immunostaining, allowing the colocalization of cellular or chromosomal proteins.

  16. Localizing introgression on the chromosome of rice by genomic in ...

    African Journals Online (AJOL)

    ... introgressed segment. Among the 200 cells analyzed, 6.5% of the cells showed hybridization signal. Signal appeared on one chromosome in 5%, on two homologous chromosomes in 1% and on sister chromatids in 0.5% of the cells. Hybridization was seen on the short arm of the chromosome 12 of the introgression line.

  17. Integrative bacterial artificial chromosomes for DNA integration into the Bacillus subtilis chromosome.

    Science.gov (United States)

    Juhas, Mario; Ajioka, James W

    2016-06-01

    Bacillus subtilis is a well-characterized model bacterium frequently used for a number of biotechnology and synthetic biology applications. Novel strategies combining the advantages of B. subtilis with the DNA assembly and editing tools of Escherichia coli are crucial for B. subtilis engineering efforts. We combined Gibson Assembly and λ red recombineering in E. coli with RecA-mediated homologous recombination in B. subtilis for bacterial artificial chromosome-mediated DNA integration into the well-characterized amyE target locus of the B. subtilis chromosome. The engineered integrative bacterial artificial chromosome iBAC(cav) can accept any DNA fragment for integration into B. subtilis chromosome and allows rapid selection of transformants by B. subtilis-specific antibiotic resistance and the yellow fluorescent protein (mVenus) expression. We used the developed iBAC(cav)-mediated system to integrate 10kb DNA fragment from E. coli K12 MG1655 into B. subtilis chromosome. iBAC(cav)-mediated chromosomal integration approach will facilitate rational design of synthetic biology applications in B. subtilis. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  18. Different structure of polytene chromosome of phaseolus coccineus suspensors during early embryogenesis. 3. Chromosome pair 6

    Energy Technology Data Exchange (ETDEWEB)

    Tagliasacchi, A.M.; Forino, L.M.C.; Cionini, P.G.; Cavallini, A.; Durante, M.; Cremonini, R.; Avanzi, S. (Pisa Univ. (Italy))

    1984-01-01

    Different regions of polytene chromosomes pair VI have been characterized by: 1. morphological observations, 2. incorporation of /sup 3/H-thymidine and /sup 3/H-uridine, 3. cytophotometry of DNA and associated proteins, 4. hybridization with satellite DNA and highly repeated DNA sequences. The collected data indicate that DNA and RNA puffs are organized by heterochromatic segments. DNA puffs show often a clustered pattern of labeling by /sup 3/H-thymidine and RNA puffs are always labeled by /sup 3/H-urindine. Each heterochromatic segment is characterized by a definite ratio between DNA and associated fastgreen stainable proteins. Satellite DNA binds mostly to heterochromatic blocks at centromers, highly repeated DNA sequences bind, with approximately the same frequency, to centromeric heterochromatin and to the main intercalary heterochromatic band. The telomeric portions of euchromatin seem to be also enriched in highly repeated DNA sequences. The results indicate that heterochromatic chromosome segments might be sites of intense localized DNA replication. The same chromosome regions are also engaged in an active transcription process. The response to hybridization suggests that heterochromatic blocks of chromosome pair VI are heterogeneous in nucleotide sequences. The present studies also indicate that DNA and RNA puffs organized by different chromosome sites are specific of particular steps of embryo differentiation. The observed metabolic aspects of the suspensior's polytene chromosomes are discussed in relation to the synthesis of growth regulators which is known to occur in the suspensor.

  19. Comparative physical mapping between wheat chromosome arm 2BL and rice chromosome 4.

    Science.gov (United States)

    Lee, Tong Geon; Lee, Yong Jin; Kim, Dae Yeon; Seo, Yong Weon

    2010-12-01

    Physical maps of chromosomes provide a framework for organizing and integrating diverse genetic information. DNA microarrays are a valuable technique for physical mapping and can also be used to facilitate the discovery of single feature polymorphisms (SFPs). Wheat chromosome arm 2BL was physically mapped using a Wheat Genome Array onto near-isogenic lines (NILs) with the aid of wheat-rice synteny and mapped wheat EST information. Using high variance probe set (HVP) analysis, 314 HVPs constituting genes present on 2BL were identified. The 314 HVPs were grouped into 3 categories: HVPs that match only rice chromosome 4 (298 HVPs), those that match only wheat ESTs mapped on 2BL (1), and those that match both rice chromosome 4 and wheat ESTs mapped on 2BL (15). All HVPs were converted into gene sets, which represented either unique rice gene models or mapped wheat ESTs that matched identified HVPs. Comparative physical maps were constructed for 16 wheat gene sets and 271 rice gene sets. Of the 271 rice gene sets, 257 were mapped to the 18-35 Mb regions on rice chromosome 4. Based on HVP analysis and sequence similarity between the gene models in the rice chromosomes and mapped wheat ESTs, the outermost rice gene model that limits the translocation breakpoint to orthologous regions was identified.

  20. Comparative chromosome painting between chicken and spectacled owl (Pulsatrix perspicillata): implications for chromosomal evolution in the Strigidae (Aves, Strigiformes).

    Science.gov (United States)

    de Oliveira, E H C; de Moura, S P; dos Anjos, L J S; Nagamachi, C Y; Pieczarka, J C; O'Brien, P C M; Ferguson-Smith, M A

    2008-01-01

    The spectacled owl (Pulsatrix perspicillata), a species found in the Neotropical region, has 76 chromosomes, with a high number of biarmed chromosomes. In order to define homologies between Gallus gallus and Pulsatrixperspicillata (Strigiformes, Strigidae), we used chromosome painting with chicken DNA probes of chromosomes 1-10 and Z and telomeric sequences. This approach allowed a comparison between Pulsatrixperspicillata and other species of Strigidae already analyzed by chromosome painting (Strix nebulosa and Bubo bubo, both with 2n = 80). The results show that centric fusions and fissions have occurred in different chromosomal pairs and are responsible for the karyotypic variation observed in this group. No interstitial telomeric sequences were found. Although the largest pair of chromosomes in P. perspicillata and Bubo bubo are submetacentric, they are homologous to different chicken chromosomes: GGA1/GGA2 in P. perspicillata and GGA2/GGA4 in B. bubo. Copyright 2008 S. Karger AG, Basel.

  1. Metaphase chromosome analysis by ligation-mediated PCR: heritable chromatin structure and a comparison of active and inactive X chromosomes.

    OpenAIRE

    Hershkovitz, M; Riggs, A D

    1995-01-01

    We report that ligation-mediated PCR (LMPCR) can be used for high-resolution study of metaphase chromosomes, and we discuss the role of metaphase chromatin structure in the preservation of differentiated cell states. The X chromosome-linked human PGK1 (phosphoglycerate kinase 1) promoter region was investigated, and euchromatic active X chromosome (Xa) metaphase chromatin was compared with interphase Xa chromatin and to heterochromatic inactive X chromosome (Xi) metaphase and interphase chrom...

  2. Modulating crossover positioning by introducing large structural changes in chromosomes.

    Science.gov (United States)

    Ederveen, Antoine; Lai, Yuching; van Driel, Marc A; Gerats, Tom; Peters, Janny L

    2015-02-15

    Crossing over assures the correct segregation of the homologous chromosomes to both poles of the dividing meiocyte. This exchange of DNA creates new allelic combinations thus increasing the genetic variation present in offspring. Crossovers are not uniformly distributed along chromosomes; rather there are preferred locations where they may take place. The positioning of crossovers is known to be influenced by both exogenous and endogenous factors as well as structural features inherent to the chromosome itself. We have introduced large structural changes into Arabidopsis chromosomes and report their effects on crossover positioning. The introduction of large deletions and putative inversions silenced recombination over the length of the structural change. In the majority of cases analyzed, the total recombination frequency over the chromosomes was unchanged. The loss of crossovers at the sites of structural change was compensated for by increases in recombination frequencies elsewhere on the chromosomes, mostly in single intervals of one to three megabases in size. Interestingly, two independent cases of induced structural changes in the same chromosomal interval were found on both chromosomes 1 and 2. In both cases, compensatory increases in recombination frequencies were of similar strength and took place in the same chromosome region. In contrast, deletions in chromosome arms carrying the nucleolar organizing region did not change recombination frequencies in the remainder of those chromosomes. When taken together, these observations show that changes in the physical structure of the chromosome can have large effects on the positioning of COs within that chromosome. Moreover, different reactions to induced structural changes are observed between and within chromosomes. However, the similarity in reaction observed when looking at chromosomes carrying similar changes suggests a direct causal relation between induced change and observed reaction.

  3. Cross-species chromosome painting tracks the independent origin of multiple sex chromosomes in two cofamiliar Erythrinidae fishes

    Directory of Open Access Journals (Sweden)

    Trifonov Vladimir

    2011-06-01

    Full Text Available Abstract Background The Erythrinidae fish family is characterized by a large variation with respect to diploid chromosome numbers and sex-determining systems among its species, including two multiple X1X2Y sex systems in Hoplias malabaricus and Erythrinus erythrinus. At first, the occurrence of a same sex chromosome system within a family suggests that the sex chromosomes are correlated and originated from ancestral XY chromosomes that were either homomorphic or at an early stage of differentiation. To identify the origin and evolution of these X1X2Y sex chromosomes, we performed reciprocal cross-species FISH experiments with two sex-chromosome-specific probes designed from microdissected X1 and Y chromosomes of H. malabaricus and E. erythrinus, respectively. Results Our results yield valuable information regarding the origin and evolution of these sex chromosome systems. Our data indicate that these sex chromosomes evolved independently in these two closed related Erythrinidae species. Different autosomes were first converted into a poorly differentiated XY sex pair in each species, and additional chromosomal rearrangements produced both X1X2Y sex systems that are currently present. Conclusions Our data provide new insights into the origin and evolution of sex chromosomes, which increases our knowledge about fish sex chromosome evolution.

  4. Interphase chromosome-specific multicolor banding (ICS-MCB): a new tool for analysis of interphase chromosomes in their integrity.

    Science.gov (United States)

    Iourov, Ivan Y; Liehr, Thomas; Vorsanova, Svetlana G; Yurov, Yuri B

    2007-10-01

    Biomedical research of interphase chromosomes in their integrity is hindered by technical limitations. We introduce a technology using microdissection-based engineering of DNA probes and fluorescence multicolor chromosome banding that allows studying interphase chromosome organization, numbers and rearrangements in somatic cells.

  5. The key role of repeated DNAs in sex chromosome evolution in two fish species with ZW sex chromosome system

    Directory of Open Access Journals (Sweden)

    de Bello Cioffi Marcelo

    2012-06-01

    Full Text Available Abstract Despite substantial progress, there are still several gaps in our knowledge about the process of sex chromosome differentiation. The degeneration of sex-specific chromosome in some species is well documented, but it is not clear if all species follow the same evolutionary pathway. The accumulation of repetitive DNA sequences, however, is a common feature. To better understand this involvement, fish species emerge as excellent models because they exhibit a wide variety of sex chromosome and sex determining systems. Besides, they have much younger sex chromosomes compared to higher vertebrates, making it possible to follow early steps of differentiation. Here, we analyzed the arrangement of 9 repetitive DNA sequences in the W chromosomes of 2 fish species, namely Leporinus reinhardti and Triportheus auritus, which present well-differentiated ZZ/ZW sex system, but differ in respect to the size of the sex-specific chromosome. Both W chromosomes are almost fully heterochromatic, with accumulation of repeated DNAs in their heterochromatic regions. We found that microsatellites have strongly accumulated on the large W chromosome of L. reinhardti but not on the reduced-size W chromosome of T. auritus and are therefore important players of the W chromosome expansion. The present data highlight that the evolution of the sex chromosomes can diverge even in the same type of sex system, with and without the degeneration of the specific-sex chromosome, being more dynamic than traditionally appreciated.

  6. Insect sex chromosomes, XI. 3H-TdR induces random aberrations in the X chromosome(s) of Gryllotalpa fossor (Orthoptera).

    Science.gov (United States)

    Sarkar, S; Rao, S R

    1992-06-01

    The pattern of titrated thymidine (3H-TdR), a direct precursor of DNA, induced aberrations on the X chromosome of Gryllotalpa fossor was examined. 3H-TdR produced aberrations randomly distributed over the entire length of the X chromosome; breaks were observed in both the eu- and the heterochromatic arms of the X chromosome in both the sexes. Since the eu- and the heterochromatic arms cannot be distinguished cytologically in this insect, the presence of aberrations on both arms of the same X chromosome in the male and damage to both X chromosomes in the female indicate that both euchromatic and heterochromatic regions (facultative or constitutive) are equally liable to aberrations induced by H-TdR. This is in contrast to the non-random induction of aberrations by 3H-UdR, which causes chromosome damage due to the proximity of the labeled RNA to the DNA template during transcription.

  7. A Study on the Chromosomes of Konya Wild Sheep (Ovis orientalis spp.): Case Report

    OpenAIRE

    KIRIKÇI, Kemal

    2003-01-01

    We investigated the shape and number of chromosomes of Konya wild sheep. A karyotype was prepared from G-band painted chromosomes. Konya wild sheep have 54 diploid chromosomes. The first three autosomal chromosomes were metacentric, and the other autosomal chromosomes and X chromosomes were acrocentric.

  8. Chromosomal Translocations: Chicken or Egg? | Center for Cancer Research

    Science.gov (United States)

    Many tumor cells have abnormal chromosomes. Some of these abnormalities are caused by chromosomal translocations, which occur when two chromosomes break and incorrectly rejoin, resulting in an exchange of genetic material. Translocations can activate oncogenes, silence tumor suppressor genes, or result in the creation of completely new fusion gene products. While there is little doubt that chromosomal translocations can contribute to cancer, there is an active "chicken and the egg" discussion about the role translocations and other chromosomal abnormalities play—do they actually cause cancer or merely occur because of other changes within the cancer cell.  

  9. Intranuclear DNA density affects chromosome condensation in metazoans.

    Science.gov (United States)

    Hara, Yuki; Iwabuchi, Mari; Ohsumi, Keita; Kimura, Akatsuki

    2013-08-01

    Chromosome condensation is critical for accurate inheritance of genetic information. The degree of condensation, which is reflected in the size of the condensed chromosomes during mitosis, is not constant. It is differentially regulated in embryonic and somatic cells. In addition to the developmentally programmed regulation of chromosome condensation, there may be adaptive regulation based on spatial parameters such as genomic length or cell size. We propose that chromosome condensation is affected by a spatial parameter called the chromosome amount per nuclear space, or "intranuclear DNA density." Using Caenorhabditis elegans embryos, we show that condensed chromosome sizes vary during early embryogenesis. Of importance, changing DNA content to haploid or polyploid changes the condensed chromosome size, even at the same developmental stage. Condensed chromosome size correlates with interphase nuclear size. Finally, a reduction in nuclear size in a cell-free system from Xenopus laevis eggs resulted in reduced condensed chromosome sizes. These data support the hypothesis that intranuclear DNA density regulates chromosome condensation. This suggests an adaptive mode of chromosome condensation regulation in metazoans.

  10. Transposable elements and early evolution of sex chromosomes in fish.

    Science.gov (United States)

    Chalopin, Domitille; Volff, Jean-Nicolas; Galiana, Delphine; Anderson, Jennifer L; Schartl, Manfred

    2015-09-01

    In many organisms, the sex chromosome pair can be recognized due to heteromorphy; the Y and W chromosomes have often lost many genes due to the absence of recombination during meiosis and are frequently heterochromatic. Repetitive sequences are found at a high proportion on such heterochromatic sex chromosomes and the evolution and emergence of sex chromosomes has been connected to the dynamics of repeats and transposable elements. With an amazing plasticity of sex determination mechanisms and numerous instances of independent emergence of novel sex chromosomes, fish represent an excellent lineage to investigate the early stages of sex chromosome differentiation, where sex chromosomes often are homomorphic and not heterochromatic. We have analyzed the composition, distribution, and relative age of TEs from available sex chromosome sequences of seven teleost fish. We observed recent bursts of TEs and simple repeat accumulations around young sex determination loci. More strikingly, we detected transposable element (TE) amplifications not only on the sex determination regions of the Y and W sex chromosomes, but also on the corresponding regions of the X and Z chromosomes. In one species, we also clearly demonstrated that the observed TE-rich sex determination locus originated from a TE-poor genomic region, strengthening the link between TE accumulation and emergence of the sex determination locus. Altogether, our results highlight the role of TEs in the initial steps of differentiation and evolution of sex chromosomes.

  11. Modeling Three-Dimensional Chromosome Structures Using Gene Expression Data.

    Science.gov (United States)

    Xiao, Guanghua; Wang, Xinlei; Khodursky, Arkady B

    2011-03-01

    Recent genomic studies have shown that significant chromosomal spatial correlation exists in gene expression of many organisms. Interestingly, coexpression has been observed among genes separated by a fixed interval in specific regions of a chromosome chain, which is likely caused by three-dimensional (3D) chromosome folding structures. Modeling such spatial correlation explicitly may lead to essential understandings of 3D chromosome structures and their roles in transcriptional regulation. In this paper, we explore chromosomal spatial correlation induced by 3D chromosome structures, and propose a hierarchical Bayesian method based on helical structures to formally model and incorporate the correlation into the analysis of gene expression microarray data. It is the first study to quantify and infer 3D chromosome structures in vivo using expression microarrays. Simulation studies show computing feasibility of the proposed method and that, under the assumption of helical chromosome structures, it can lead to precise estimation of structural parameters and gene expression levels. Real data applications demonstrate an intriguing biological phenomenon that functionally associated genes, which are far apart along the chromosome chain, are brought into physical proximity by chromosomal folding in 3D space to facilitate their coexpression. It leads to important biological insight into relationship between chromosome structure and function.

  12. Bacterial Artificial Chromosome Mutagenesis Using Recombineering

    Directory of Open Access Journals (Sweden)

    Kumaran Narayanan

    2011-01-01

    Full Text Available Gene expression from bacterial artificial chromosome (BAC clones has been demonstrated to facilitate physiologically relevant levels compared to viral and nonviral cDNA vectors. BACs are large enough to transfer intact genes in their native chromosomal setting together with flanking regulatory elements to provide all the signals for correct spatiotemporal gene expression. Until recently, the use of BACs for functional studies has been limited because their large size has inherently presented a major obstacle for introducing modifications using conventional genetic engineering strategies. The development of in vivo homologous recombination strategies based on recombineering in E. coli has helped resolve this problem by enabling facile engineering of high molecular weight BAC DNA without dependence on suitably placed restriction enzymes or cloning steps. These techniques have considerably expanded the possibilities for studying functional genetics using BACs in vitro and in vivo.

  13. American marsupials chromosomes: why study them?

    Directory of Open Access Journals (Sweden)

    Marta Svartman

    2009-01-01

    Full Text Available Marsupials, one of the three main groups of mammals, are only found in Australia and in the American continent. Studies performed in Australian marsupials have demonstrated the great potential provided by the group for the understanding of basic genetic mechanisms and chromosome evolution in mammals. Genetic studies in American marsupials are relatively scarce and cytogenetic data of most species are restricted to karyotype descriptions, usually without banding patterns. Nevertheless, the first marsupial genome sequenced was that of Monodelphis domestica, a South American species. The knowledge about mammalian genome evolution and function that resulted from studies on M. domestica is in sharp contrast with the lack of genetic data on most American marsupial species. Here, we present an overview of the chromosome studies performed in marsupials with emphasis on the South American species.

  14. Antibodies against chromosomal beta-lactamase

    DEFF Research Database (Denmark)

    Giwercman, B; Rasmussen, J W; Ciofu, Oana

    1994-01-01

    A murine monoclonal anti-chromosomal beta-lactamase antibody was developed and an immunoblotting technique was used to study the presence of serum and sputum antibodies against Pseudomonas aeruginosa chromosomal group 1 beta-lactamase in patients with cystic fibrosis (CF). The serum antibody...... response was studied with serum samples collected in 1992 from 56 CF patients in a cross-sectional study and with serum samples from 18 CF patients in a longitudinal study. Anti-beta-lactamase immunoglobulin G antibodies were present in all of the serum samples from the patients with chronic...... bronchopulmonary P. aeruginosa infection (CF + P) but in none of the CF patients with no or intermittent P. aeruginosa infection. Anti-beta-lactamase antibodies were present in serum from CF + P patients after six antipseudomonal courses (median) and correlated with infection with a beta-lactam-resistant strain...

  15. Evolutionarily conserved sequences on human chromosome 21

    Energy Technology Data Exchange (ETDEWEB)

    Frazer, Kelly A.; Sheehan, John B.; Stokowski, Renee P.; Chen, Xiyin; Hosseini, Roya; Cheng, Jan-Fang; Fodor, Stephen P.A.; Cox, David R.; Patil, Nila

    2001-09-01

    Comparison of human sequences with the DNA of other mammals is an excellent means of identifying functional elements in the human genome. Here we describe the utility of high-density oligonucleotide arrays as a rapid approach for comparing human sequences with the DNA of multiple species whose sequences are not presently available. High-density arrays representing approximately 22.5 Mb of nonrepetitive human chromosome 21 sequence were synthesized and then hybridized with mouse and dog DNA to identify sequences conserved between humans and mice (human-mouse elements) and between humans and dogs (human-dog elements). Our data show that sequence comparison of multiple species provides a powerful empiric method for identifying actively conserved elements in the human genome. A large fraction of these evolutionarily conserved elements are present in regions on chromosome 21 that do not encode known genes.

  16. [Chromosomal rearrangements and fusion genes in carcinoma].

    Science.gov (United States)

    Massard, Christophe; Auger, Nathalie; Lacroix, Ludovic; Bénard, Jean

    2011-12-01

    In the last decades, rarity of chromosomal rearrangements and fusion genes detected in epithelial cancers in using classical karyotyping led to consider these genomic events as specifically restricted to haematological neoplasia and mesenchymal tumors. Today, gene positioning as well as bio-informatics approaches has enabled identifying in carcinoma various fusion genes subsequent to chromosomal translocations, inversions, or deletions. Thus, gene fusion formation appears as a common mechanism in oncology that concerns most of human cancers, independent of original tissue lineage. At a clinical point of view, applications of fusion genes in terms of diagnosis, prognosis and therapeutics can be envisioned. This review will present current knowledge about fusion genes in common carcinoma (prostate, breast, colon). Following a structural and functional description of various fusion genes so far found in human malignant solid tumors, as well as techniques used for their detection, the review will integrate fusion genes in epithelia oncogenesis general scheme. Finally, promising clinical issues of fusion genes will be surveyed.

  17. Diagnosis of Fanconi Anemia: Chromosomal Breakage Analysis

    Directory of Open Access Journals (Sweden)

    Anneke B. Oostra

    2012-01-01

    Full Text Available Fanconi anemia (FA is a rare inherited syndrome with diverse clinical symptoms including developmental defects, short stature, bone marrow failure, and a high risk of malignancies. Fifteen genetic subtypes have been distinguished so far. The mode of inheritance for all subtypes is autosomal recessive, except for FA-B, which is X-linked. Cells derived from FA patients are—by definition—hypersensitive to DNA cross-linking agents, such as mitomycin C, diepoxybutane, or cisplatinum, which becomes manifest as excessive growth inhibition, cell cycle arrest, and chromosomal breakage upon cellular exposure to these drugs. Here we provide a detailed laboratory protocol for the accurate assessment of the FA diagnosis as based on mitomycin C-induced chromosomal breakage analysis in whole-blood cultures. The method also enables a quantitative estimate of the degree of mosaicism in the lymphocyte compartment of the patient.

  18. Diagnosis of Fanconi Anemia: Chromosomal Breakage Analysis

    Science.gov (United States)

    Oostra, Anneke B.; Nieuwint, Aggie W. M.; Joenje, Hans; de Winter, Johan P.

    2012-01-01

    Fanconi anemia (FA) is a rare inherited syndrome with diverse clinical symptoms including developmental defects, short stature, bone marrow failure, and a high risk of malignancies. Fifteen genetic subtypes have been distinguished so far. The mode of inheritance for all subtypes is autosomal recessive, except for FA-B, which is X-linked. Cells derived from FA patients are—by definition—hypersensitive to DNA cross-linking agents, such as mitomycin C, diepoxybutane, or cisplatinum, which becomes manifest as excessive growth inhibition, cell cycle arrest, and chromosomal breakage upon cellular exposure to these drugs. Here we provide a detailed laboratory protocol for the accurate assessment of the FA diagnosis as based on mitomycin C-induced chromosomal breakage analysis in whole-blood cultures. The method also enables a quantitative estimate of the degree of mosaicism in the lymphocyte compartment of the patient. PMID:22693659

  19. Chromosome Dynamics in the Yeast Interphase Nucleus

    Science.gov (United States)

    Heun, Patrick; Laroche, Thierry; Shimada, Kenji; Furrer, Patrick; Gasser, Susan M.

    2001-12-01

    Little is known about the dynamics of chromosomes in interphase nuclei. By tagging four chromosomal regions with a green fluorescent protein fusion to lac repressor, we monitored the movement and subnuclear position of specific sites in the yeast genome, sampling at short time intervals. We found that early and late origins of replication are highly mobile in G1 phase, frequently moving at or faster than 0.5 micrometers/10 seconds, in an energy-dependent fashion. The rapid diffusive movement of chromatin detected in G1 becomes constrained in S phase through a mechanism dependent on active DNA replication. In contrast, telomeres and centromeres provide replication-independent constraint on chromatin movement in both G1 and S phases.

  20. Chromosomal organization of transcription: in a nutshell.

    Science.gov (United States)

    Meyer, Sam; Reverchon, Sylvie; Nasser, William; Muskhelishvili, Georgi

    2017-11-28

    Early studies of transcriptional regulation focused on individual gene promoters defined specific transcription factors as central agents of genetic control. However, recent genome-wide data propelled a different view by linking spatially organized gene expression patterns to chromosomal dynamics. Therefore, the major problem in contemporary molecular genetics concerned with transcriptional gene regulation is to establish a unifying model that reconciles these two views. This problem, situated at the interface of polymer physics and network theory, requires development of an integrative methodology. In this review, we discuss recent achievements in classical model organism E. coli and provide some novel insights gained from studies of a bacterial plant pathogen, D. dadantii. We consider DNA topology and the basal transcription machinery as key actors of regulation, in which activation of functionally relevant genes is coupled to and coordinated with the establishment of extended chromosomal domains of coherent transcription. We argue that the spatial organization of genome plays a fundamental role in its own regulation.

  1. Chromosomes of American species of Sida (Malvaceae

    Directory of Open Access Journals (Sweden)

    Graciela I. Lavia

    2007-09-01

    Full Text Available Chromosome numbers are reported for 26 accessions of Sida (Malvaceae from Argentina, Bolivia, Brazil, México and Paraguay representing 15 species. First chromosome counts are cited for the following 8 species: S. Charpinii Krapov. 2n=14, S. ciliaris L. 2n=16, S. Monteiroi Krapov. 2n=16, S. anomala A. St.-Hil. 2n=16,S. Cristobaliana Krapov. 2n=32, S. dubia A. St.-Hil. & Naudin 2n=14, S. Poeppigiana (K.Schum. Fryxell 2n=14 and S. Leitaofilhoi Krapov. 2n=14.

  2. Calcium ions function as a booster of chromosome condensation.

    Science.gov (United States)

    Phengchat, Rinyaporn; Takata, Hideaki; Morii, Kenichi; Inada, Noriko; Murakoshi, Hideji; Uchiyama, Susumu; Fukui, Kiichi

    2016-12-02

    Chromosome condensation is essential for the faithful transmission of genetic information to daughter cells during cell division. The depletion of chromosome scaffold proteins does not prevent chromosome condensation despite structural defects. This suggests that other factors contribute to condensation. Here we investigated the contribution of divalent cations, particularly Ca 2+ , to chromosome condensation in vitro and in vivo. Ca 2+ depletion caused defects in proper mitotic progression, particularly in chromosome condensation after the breakdown of the nuclear envelope. Fluorescence lifetime imaging microscopy-Förster resonance energy transfer and electron microscopy demonstrated that chromosome condensation is influenced by Ca 2+ . Chromosomes had compact globular structures when exposed to Ca 2+ and expanded fibrous structures without Ca 2+ . Therefore, we have clearly demonstrated a role for Ca 2+ in the compaction of chromatin fibres.

  3. Calcium ions function as a booster of chromosome condensation

    Science.gov (United States)

    Phengchat, Rinyaporn; Takata, Hideaki; Morii, Kenichi; Inada, Noriko; Murakoshi, Hideji; Uchiyama, Susumu; Fukui, Kiichi

    2016-01-01

    Chromosome condensation is essential for the faithful transmission of genetic information to daughter cells during cell division. The depletion of chromosome scaffold proteins does not prevent chromosome condensation despite structural defects. This suggests that other factors contribute to condensation. Here we investigated the contribution of divalent cations, particularly Ca2+, to chromosome condensation in vitro and in vivo. Ca2+ depletion caused defects in proper mitotic progression, particularly in chromosome condensation after the breakdown of the nuclear envelope. Fluorescence lifetime imaging microscopy-Förster resonance energy transfer and electron microscopy demonstrated that chromosome condensation is influenced by Ca2+. Chromosomes had compact globular structures when exposed to Ca2+ and expanded fibrous structures without Ca2+. Therefore, we have clearly demonstrated a role for Ca2+ in the compaction of chromatin fibres. PMID:27910894

  4. Linking Chromosome Duplication and Segregation via Sister Chromatid Cohesion

    Science.gov (United States)

    Leman, Adam R.; Noguchi, Eishi

    2014-01-01

    DNA replication during S phase generates two identical copies of each chromosome. Each chromosome is destined for a daughter cell, but each daughter must receive one and only one copy of each chromosome. To ensure accurate chromosome segregation, eukaryotic cells are equipped with a mechanism to pair the chromosomes during chromosome duplication and hold the pairs until a bi-oriented mitotic spindle is formed and the pairs are pulled apart. This mechanism is known as sister chromatid cohesion, and its actions span the entire cell cycle. During G1, before DNA is copied during S phase, proteins termed cohesins are loaded onto DNA. Paired chromosomes are held together through G2 phase, and finally the cohesins are dismantled during mitosis. The processes governing sister chromatid cohesion ensure that newly replicated sisters are held together from the moment they are generated to the metaphase–anaphase transition, when sisters separate. PMID:24906310

  5. Transmission Behavior of B Chromosomes in Prochilodus lineatus (Characiformes, Prochilodontidae).

    Science.gov (United States)

    Penitente, Manolo; Daniel, Sandro N; Senhorini, José A; Foresti, Fausto; Porto-Foresti, Fábio

    2015-01-01

    The population of Prochilodus lineatus found in the Mogi-Guaçu River is karyotypically polymorphic, carrying acrocentric, metacentric, and submetacentric B chromosomes. The analysis of each B chromosome frequency in this species revealed a variation in the distribution pattern, with the metacentric type having the highest frequency (73.30%), followed by submetacentric (25.22%) and acrocentric B chromosomes (1.48%). The transmission pattern of the supernumerary chromosomes was identified by controlled crosses, and it was shown that the acro- and submetacentric B chromosomes have a transmission pattern below the Mendelian rate (kB = 0.333 and kB = 0.385, respectively), but the metacentric variant has a cumulative transmission pattern (kB = 0.587). These results indicate that the acro- and submetacentric B chromosomes are undergoing an extinction process, while the metacentric B chromosomes appear to be accumulating in frequency with each generation. © 2016 S. Karger AG, Basel.

  6. SMC complexes differentially compact mitotic chromosomes according to genomic context.

    Science.gov (United States)

    Schalbetter, Stephanie Andrea; Goloborodko, Anton; Fudenberg, Geoffrey; Belton, Jon-Matthew; Miles, Catrina; Yu, Miao; Dekker, Job; Mirny, Leonid; Baxter, Jonathan

    2017-09-01

    Structural maintenance of chromosomes (SMC) protein complexes are key determinants of chromosome conformation. Using Hi-C and polymer modelling, we study how cohesin and condensin, two deeply conserved SMC complexes, organize chromosomes in the budding yeast Saccharomyces cerevisiae. The canonical role of cohesin is to co-align sister chromatids, while condensin generally compacts mitotic chromosomes. We find strikingly different roles for the two complexes in budding yeast mitosis. First, cohesin is responsible for compacting mitotic chromosome arms, independently of sister chromatid cohesion. Polymer simulations demonstrate that this role can be fully accounted for through cis-looping of chromatin. Second, condensin is generally dispensable for compaction along chromosome arms. Instead, it plays a targeted role compacting the rDNA proximal regions and promoting resolution of peri-centromeric regions. Our results argue that the conserved mechanism of SMC complexes is to form chromatin loops and that distinct SMC-dependent looping activities are selectively deployed to appropriately compact chromosomes.

  7. Chromosomal association of Ran during meiotic and mitotic divisions.

    Science.gov (United States)

    Hinkle, Beth; Slepchenko, Boris; Rolls, Melissa M; Walther, Tobias C; Stein, Pascal A; Mehlmann, Lisa M; Ellenberg, Jan; Terasaki, Mark

    2002-12-01

    Recent studies in Xenopus egg extracts indicate that the small G protein Ran has a central role in spindle assembly and nuclear envelope reformation. We determined Ran localization and dynamics in cells during M phase. By immunofluorescence, Ran is accumulated on the chromosomes of meiosis-II-arrested Xenopus eggs. In living cells, fluorescently labeled Ran associated with the chromosomes in Xenopus and remained associated during anaphase when eggs were artificially activated. Fluorescent Ran associated with chromosomes in mouse eggs, during meiotic maturation and early embryonic divisions in starfish, and to a lesser degree during mitosis of a cultured mammalian cell line. Chromosomal Ran undergoes constant flux. From photobleach experiments in immature starfish oocytes, chromosomal Ran has a k(off) of approximately 0.06 second(-1), and binding analysis suggests that there is a single major site. The chromosomal interactions may serve to keep Ran-GTP in the vicinity of the chromosomes for spindle assembly and nuclear envelope reformation.

  8. Chromosomal aberrations of malignant pleural effusions of lung adenocarcinoma: different cytogenetic changes are correlated with genders and smoking habits.

    Science.gov (United States)

    Yen, Chueh-Chuan; Liang, Shu-Ching; Jong, Yiin-Jeng; Chen, Yann-Jang; Lin, Chi-Hung; Chen, Yuh-Min; Wu, Yu-Chung; Su, Wu-Chou; Huang, Chi-Ying F; Tseng, Szu-Wen; Whang-Peng, Jacqueline

    2007-09-01

    Chromosomal aberrations of malignant cells from pleural effusions of 31 cases of lung adenocarcinoma were analyzed. Pooled CGH results showed frequent amplifications on chromosome arms 1p (22.6%), 1q (35.5%), 2q (25.8%), 3q (38.7%), 4q (41.9%), 5p (41.9%), 5q (51.6%), 6p (19.4%), 6q (25.8%), 7p (41.9%), 7q (35.5%), 8q (32.3%), 12q (38.7%), 13q (22.6%), 14q (35.5%), 17q (19.4%), Xp (22.6%), and Xq (38.7%). Frequent deletions were found on 1p (19.4%), 3p (16.1%), 4q (16.1%), 8p (25.8%), 9p (22.6%), 9q (29.0%), 10q (22.6%), 13q (22.6%), 16p (19.4%), 16q (22.6%), 17p (29.0%), 18q (16.1%), 19p (41.9%), 19q (32.3%), 20p (19.4%) and 22q (29%). These genomic changes were generally found consistent with previous reports of CGH analysis of primary tumors of lung adenocarcinoma. Loss of 19q and 22q were more frequently found in our studies (32.3% and 29.0%, respectively) than studies of primary tumors (less than 7% for both genetic changes). Gain of 11p, although not a frequent finding, was relatively more common in this (16%) than other studies (range, 2.9-11.8%). Interestingly, occurrences of 3p loss and 11p gain were higher in smokers than non-smokers, and deletion of 3p and increased copy number of 11p and Xp appeared more often in male than female patients. Among 17 male patients, gain of chromosomal 11p was a frequent aberration in tumors of smokers, while gain of Xp was more easily found in tumors of non-smokers. One candidate gene located within 11p15, lactate dehydrogenase C (LDHC), was selected for further study. Three cases with 11p gain had amplified FISH signals of LDHC. Also tumors from smokers or male had significantly higher transcript level of LDHC than non-smokers or female, respectively. The results demonstrate that different cytogenetic changes of malignant pleural effusions from lung adenocarcinoma are correlated with genders and smoking habits. The role of LDHC in the carcinogenesis of smoking-related lung adenocarcinoma, especially in male patients with

  9. Cytogenetic analysis shows that the unusually large chromosome in the sex-limited pB silkworm (Bombyx mori) strain consists of three chromosomes.

    Science.gov (United States)

    Tanaka, N; Yokoyama, T; Abe, H; Tsuchida, K; Ninagi, O; Oshiki, T

    2000-01-01

    We have discovered an inordinately large chromosome pair at the pachytene stage in the oocyte of the sex-limited pB (black larval marking) silkworm (Bombyx mori) strain (TWPB). We have analyzed the composition and arrangement of this large chromosome. A genetic linkage analysis shows that the large chromosome is made up of the W chromosome, the second chromosome fragment (pB fragment), and the fifth chromosome (linkage group) containing at least the region from map position 0.0 to 40.8. We also observed a sex heterochromatin body (SB) that we deduced to be made up of condensed W chromosomes. The number of SBs in each female nucleus among the sucking stomach cells of the TWPB strain was variable. Evidently, the W chromosome of the TWPB strain is attached to another chromosome. The composition of the W chromosome, the second chromosome fragment, and the fifth chromosome was studied through linkage analysis for these three chromosomes. We used two strains derived from the TWPB strain, the sex-limited pM (moricaud larval marking)-like (TWPML) and the autosomal pM-like (T5PML). The results show that the TWPML strain originates through a detachment of the fifth chromosome from the large chromosome of the TWPB strain, and the T5PML strain originates through a detachment of the W chromosome from that. Accordingly, the large chromosome of the TWPB strain is arranged in the order W chromosome--second chromosome fragment--fifth chromosome.

  10. CHROMOSOME TRANSFER KINETICS OF SALMONELLA HFR STRAINS.

    Science.gov (United States)

    JOHNSON, E M; FALKOW, S; BARON, L S

    1964-08-01

    Johnson, E. M. (Walter Reed Army Institute of Research, Washington, D.C.), Stanley Falkow, and L. S. Baron. Chromosome transfer kinetics of Salmonella Hfr strains. J. Bacteriol. 88:395-400. 1964.-The kinetics of chromosome transfer of an Hfr strain of Salmonella typhosa and an Hfr strain of S. typhimurium were examined in interrupted matings with multiply auxotrophic S. typhimurium recipients. The S. typhosa Hfr, TD-7, was found to transfer the pro-A, met-A, arg (A, C, F, or H), and ile markers at 8, 32, 36, and 51 min, respectively, after contact with the recipient strain. Comparison of these entry times with those of the analogous Escherichia coli Hfr P4X-6 for the same markers showed the gene order to be identical. However, the TD-7 entry times were considerably extended over those of P4X-6, which transfers these markers of E. coli F(-) strains at, respectively, 5, 20, 22.5, and 28 min. A similar extension of the entry times was noted with the S. typhimurium Hfr, SR-305, which transfers the markers in the reverse order, ile-met-A-pro-A, at 3 to 4, 18, and 46 min, respectively. Examination of P4X-6/Salmonella Hfr entry time ratios showed them to be constant at 0.63 for the earlier markers transferred by both TD-7 and SR-305. These data suggest that the physical length of the Salmonella chromosome is the same as that of E. coli, and that the rate of chromosome transfer of the Salmonella Hfr strains to S. typhimurium recipients is only 0.63 that of P4X-6 to E. coli F(-) strains under the same physical conditions.

  11. X chromosome inactivation in women with alcoholism.

    Science.gov (United States)

    Manzardo, Ann M; Henkhaus, Rebecca; Hidaka, Brandon; Penick, Elizabeth C; Poje, Albert B; Butler, Merlin G

    2012-08-01

    All female mammals with 2 X chromosomes balance gene expression with males having only 1 X by inactivating one of their X chromosomes (X chromosome inactivation [XCI]). Analysis of XCI in females offers the opportunity to investigate both X-linked genetic factors and early embryonic development that may contribute to alcoholism. Increases in the prevalence of skewing of XCI in women with alcoholism could implicate biological risk factors. The pattern of XCI was examined in DNA isolated in blood from 44 adult women meeting DSM-IV criteria for an alcohol use disorder and 45 control women with no known history of alcohol abuse or dependence. XCI status was determined by analyzing digested and undigested polymerase chain reaction (PCR) products of the polymorphic androgen receptor (AR) gene located on the X chromosome. Subjects were categorized into 3 groups based upon the degree of XCI skewness: random (50:50 to 64:36%), moderately skewed (65:35 to 80:20%), and highly skewed (>80:20%). XCI status from informative women with alcoholism was found to be random in 59% (n = 26), moderately skewed in 27% (n = 12), or highly skewed in 14% (n = 6). Control subjects showed 60, 29, and 11%, respectively. The distribution of skewed XCI observed among women with alcoholism did not differ statistically from that of control subjects (χ(2) test = 0.14, 2 df, p = 0.93). Our data did not support an increase in XCI skewness among women with alcoholism or implicate early developmental events associated with embryonic cell loss or unequal (nonrandom) expression of X-linked gene(s) or defects in alcoholism among women. Copyright © 2012 by the Research Society on Alcoholism.

  12. Chromosomal Microarray versus Karyotyping for Prenatal Diagnosis

    Science.gov (United States)

    Wapner, Ronald J.; Martin, Christa Lese; Levy, Brynn; Ballif, Blake C.; Eng, Christine M.; Zachary, Julia M.; Savage, Melissa; Platt, Lawrence D.; Saltzman, Daniel; Grobman, William A.; Klugman, Susan; Scholl, Thomas; Simpson, Joe Leigh; McCall, Kimberly; Aggarwal, Vimla S.; Bunke, Brian; Nahum, Odelia; Patel, Ankita; Lamb, Allen N.; Thom, Elizabeth A.; Beaudet, Arthur L.; Ledbetter, David H.; Shaffer, Lisa G.; Jackson, Laird

    2013-01-01

    Background Chromosomal microarray analysis has emerged as a primary diagnostic tool for the evaluation of developmental delay and structural malformations in children. We aimed to evaluate the accuracy, efficacy, and incremental yield of chromosomal microarray analysis as compared with karyotyping for routine prenatal diagnosis. Methods Samples from women undergoing prenatal diagnosis at 29 centers were sent to a central karyotyping laboratory. Each sample was split in two; standard karyotyping was performed on one portion and the other was sent to one of four laboratories for chromosomal microarray. Results We enrolled a total of 4406 women. Indications for prenatal diagnosis were advanced maternal age (46.6%), abnormal result on Down’s syndrome screening (18.8%), structural anomalies on ultrasonography (25.2%), and other indications (9.4%). In 4340 (98.8%) of the fetal samples, microarray analysis was successful; 87.9% of samples could be used without tissue culture. Microarray analysis of the 4282 nonmosaic samples identified all the aneuploidies and unbalanced rearrangements identified on karyotyping but did not identify balanced translocations and fetal triploidy. In samples with a normal karyotype, microarray analysis revealed clinically relevant deletions or duplications in 6.0% with a structural anomaly and in 1.7% of those whose indications were advanced maternal age or positive screening results. Conclusions In the context of prenatal diagnostic testing, chromosomal microarray analysis identified additional, clinically significant cytogenetic information as compared with karyotyping and was equally efficacious in identifying aneuploidies and unbalanced rearrangements but did not identify balanced translocations and triploidies. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development and others; ClinicalTrials.gov number, NCT01279733.) PMID:23215555

  13. Chromosome abnormalities in primary ovarian cancer

    Energy Technology Data Exchange (ETDEWEB)

    Yonescu, R.; Currie, J.; Griffin, C.A. [John Hopkins Univ., Baltimore, MD (United States)

    1994-09-01

    Chromosome abnormalities that are specific and recurrent may occur in regions of the genome that are involved in the conversion of normal cells to those with tumorigenic potential. Ovarian cancer is the primary cause of death among patients with gynecological malignancies. We have performed cytogenetic analysis of 16 ovarian tumors from women age 28-82. Three tumors of low malignant potential and three granulosa cell tumors had normal karyotypes. To look for the presence of trisomy 12, which has been suggested to be a common aberration in this group of tumors, interphase fluorescence in situ hybridization was performed on direct preparations from three of these tumors using a probe for alpha satellite sequences of chromosome 12. In the 3 preparations, 92-98 percent of the cells contained two copies of chromosome 12, indicating that trisomy 12 is not a universal finding in low grade ovarian tumors. Endometrioid carcinoma of the ovary is histologically indistinguishable from endometial carcinoma of the uterus. We studied 10 endometrioid tumors to determine the degree of genetic similarity between these two carcinomas. Six out of ten endometrioid tumors showed a near-triploid modal number, and one presented with a tetraploid modal number. Eight of the ten contained structural chromosome abnormalities, of which the most frequent were 1p- (5 tumors), 19q+ (3 tumors), 6q- or ins(6) (4 tumors), 3q- or 3q+ (4 tumors). These cytogenetic results resemble those reported for papillary ovarian tumors and differ from those of endometrial carcinoma of the uterus. We conclude that despite the histologic similarities between the endometrioid and endometrial carcinomas, the genetic abnormalities in the genesis of these tumors differ significantly.

  14. Y-chromosome STR haplotypes in Somalis

    DEFF Research Database (Denmark)

    Hallenberg, Charlotte; Simonsen, Bo; Sanchez Sanchez, Juan Jose

    2005-01-01

    A total of 201 males from Somalia were typed for the Y-chromosome STRs DYS19, DYS385a/b, DYS389-I, DYS389-II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438 and DYS439 with the PowerPlex Y kit (Promega). A total of 96 different haplotypes were observed and the haplotype diversity was 0.......9715. The number of unique haplotypes was 71 while the most common haplotype was observed 24 times....

  15. Mosaicism for a chromosome 8-derived minute marker chromosome in a patient with manifestations of trisomy 8 mosaicism

    Energy Technology Data Exchange (ETDEWEB)

    Spinner, N.B.; Grace, K.R.; Owens, N.L. [Children`s Hospital of Philadelphia, PA (United States)] [and others

    1995-03-13

    We describe a patient with manifestations of the mosaic trisomy 8 syndrome and mosaicism for a minute marker chromosome. Fluorescence in situ hybridization (FISH) with a chromosome 8 probe confirmed that the marker was derived from chromosome 8. This is the smallest piece of chromosome 8 to be reported in a patient with mosaic trisomy 8 syndrome. When the clinical picture is strongly suggestive of trisomy for a specific chromosome region, we believe that FISH can be used to test markers in a guided, rather than random, fashion. 8 refs., 3 figs.

  16. Chromosomes in the flow to simplify genome analysis.

    Science.gov (United States)

    Doležel, Jaroslav; Vrána, Jan; Safář, Jan; Bartoš, Jan; Kubaláková, Marie; Simková, Hana

    2012-08-01

    Nuclear genomes of human, animals, and plants are organized into subunits called chromosomes. When isolated into aqueous suspension, mitotic chromosomes can be classified using flow cytometry according to light scatter and fluorescence parameters. Chromosomes of interest can be purified by flow sorting if they can be resolved from other chromosomes in a karyotype. The analysis and sorting are carried out at rates of 10(2)-10(4) chromosomes per second, and for complex genomes such as wheat the flow sorting technology has been ground-breaking in reducing genome complexity for genome sequencing. The high sample rate provides an attractive approach for karyotype analysis (flow karyotyping) and the purification of chromosomes in large numbers. In characterizing the chromosome complement of an organism, the high number that can be studied using flow cytometry allows for a statistically accurate analysis. Chromosome sorting plays a particularly important role in the analysis of nuclear genome structure and the analysis of particular and aberrant chromosomes. Other attractive but not well-explored features include the analysis of chromosomal proteins, chromosome ultrastructure, and high-resolution mapping using FISH. Recent results demonstrate that chromosome flow sorting can be coupled seamlessly with DNA array and next-generation sequencing technologies for high-throughput analyses. The main advantages are targeting the analysis to a genome region of interest and a significant reduction in sample complexity. As flow sorters can also sort single copies of chromosomes, shotgun sequencing DNA amplified from them enables the production of haplotype-resolved genome sequences. This review explains the principles of flow cytometric chromosome analysis and sorting (flow cytogenetics), discusses the major uses of this technology in genome analysis, and outlines future directions.

  17. Chromosome length scaling in haploid, asexual reproduction

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, P M C de [Instituto de Fisica, Universidade Federal Fluminense, avenida Litoranea s/n, Boa Viagem, Niteroi 24210-340 (Brazil)

    2007-02-14

    We study the genetic behaviour of a population formed by haploid individuals which reproduce asexually. The genetic information for each individual is stored along a bit-string (or chromosome) with L bits, where 0-bits represent the wild allele and 1-bits correspond to harmful mutations. Each newborn inherits this chromosome from its parent with a few random mutations: on average a fixed number m of bits are flipped. Selection is implemented according to the number N of 1-bits counted along the individual's chromosome: the smaller N the higher the probability an individual has to survive a new time step. Such a population evolves, with births and deaths, and its genetic distribution becomes stabilized after sufficiently many generations have passed. The question we pose concerns the procedure of increasing L. The aim is to get the same distribution of genetic loads N/L among the equilibrated population, in spite of a larger L. Should we keep the same mutation rate m/L for different values of L? The answer is yes, which intuitively seems to be plausible. However, this conclusion is not trivial, according to our simulation results: the question also involves the population size.

  18. Y chromosomal STR analysis using Pyrosequencing technology.

    Science.gov (United States)

    Edlund, Hanna; Allen, Marie

    2009-03-01

    Analysis of Y chromosome STR markers has proven to be useful in forensic cases where the samples contain a mixture of DNA from several individuals. STR markers are commonly genotyped based on length separation of PCR products. In this study we evaluated if Pyrosequencing can be used as an alternative method for determining Y-STR variants. In total 70 unrelated Swedish males were typed for the Y chromosomal markers (DYS19, DYS389 I-II, DYS390, DYS391, DYS392, DYS393 and DYS438) using Pyrosequencing. Using the 8 markers, 57 unique haplotypes were observed with a discrimination capacity of 0.81. At four loci, the Pyrosequencing analysis revealed sequence variants. The sequence variants were found in the DYS389 II, DYS390, DYS391, and DYS393 loci in frequencies between 1.43% and 14.3%. Pyrosequencing has here been shown to be a useful tool for typing Y chromosomal STRs and the method can provide a complement to conventional forensic Y STR analyses. Moreover, the Pyrosequencing method can be used to rapidly evaluate novel markers.

  19. Resolving spatial inconsistencies in chromosome conformation measurements.

    Science.gov (United States)

    Duggal, Geet; Patro, Rob; Sefer, Emre; Wang, Hao; Filippova, Darya; Khuller, Samir; Kingsford, Carl

    2013-03-09

    Chromosome structure is closely related to its function and Chromosome Conformation Capture (3C) is a widely used technique for exploring spatial properties of chromosomes. 3C interaction frequencies are usually associated with spatial distances. However, the raw data from 3C experiments is an aggregation of interactions from many cells, and the spatial distances of any given interaction are uncertain. We introduce a new method for filtering 3C interactions that selects subsets of interactions that obey metric constraints of various strictness. We demonstrate that, although the problem is computationally hard, near-optimal results are often attainable in practice using well-designed heuristics and approximation algorithms. Further, we show that, compared with a standard technique, this metric filtering approach leads to (a) subgraphs with higher statistical significance, (b) lower embedding error, (c) lower sensitivity to initial conditions of the embedding algorithm, and (d) structures with better agreement with light microscopy measurements. Our filtering scheme is applicable for a strict frequency-to-distance mapping and a more relaxed mapping from frequency to a range of distances. Our filtering method for 3C data considers both metric consistency and statistical confidence simultaneously resulting in lower-error embeddings that are biologically more plausible.

  20. [Fluorescence in situ hybridization with DNA probes derived from individual chromosomes and chromosome regions].

    Science.gov (United States)

    Bogomolov, A G; Karamysheva, T V; Rubtsov, N B

    2014-01-01

    A significant part of the eukaryotic genomes consists of repetitive DNA, which can form large clusters or distributed along euchromatic chromosome regions. Repeats located in chromosomal regions make a problem in analysis and identification of the chromosomal material with fluorescence in situ hybridization (FISH). In most cases, the identification of chromosome regions using FISH requires detection of the signal produced with unique sequences. The feasibility, advantages and disadvantages of traditional methods of suppression of repetitive DNA hybridization, methods of repeats-free probe construction and methods of chromosome-specific DNA sequences visualization using image processing of multicolor FISH results are considered in the paper. The efficiency of different techniques for DNA probe generation, different FISH protocols, and image processing of obtained microscopic images depends on the genomic size and structure of analyzing species. This problem was discussed and different approaches were considered for the analysis of the species with very large genome, rare species and species which specimens are too small in size to obtain the amount of genomic and Cot-1 DNA required for suppression of repetitive DNA hybridization.

  1. Chromosomal rearrangements and karyotype evolution in carnivores revealed by chromosome painting

    Science.gov (United States)

    Nie, W; Wang, J; Su, W; Wang, D; Tanomtong, A; Perelman, P L; Graphodatsky, A S; Yang, F

    2012-01-01

    Chromosomal evolution in carnivores has been revisited extensively using cross-species chromosome painting. Painting probes derived from flow-sorted chromosomes of the domestic dog, which has one of the most rearranged karyotypes in mammals and the highest dipoid number (2n=78) in carnivores, are a powerful tool in detecting both evolutionary intra- and inter-chromosomal rearrangements. However, only a few comparative maps have been established between dog and other non-Canidae species. Here, we extended cross-species painting with dog probes to seven more species representing six carnivore families: Eurasian lynx (Lynx lynx), the stone marten (Martes foina), the small Indian civet (Viverricula indica), the Asian palm civet (Paradoxurus hermaphrodites), Javan mongoose (Hepestes javanicas), the raccoon (Procyon lotor) and the giant panda (Ailuropoda melanoleuca). The numbers and positions of intra-chromosomal rearrangements were found to differ among these carnivore species. A comparative map between human and stone marten, and a map among the Yangtze finless porpoise (Neophocaena phocaenoides asiaeorientalis), stone marten and human were also established to facilitate outgroup comparison and to integrate comparative maps between stone marten and other carnivores with such maps between human and other species. These comparative maps give further insight into genome evolution and karyotype phylogenetic relationships among carnivores, and will facilitate the transfer of gene mapping data from human, domestic dog and cat to other species. PMID:22086079

  2. Distribution of X-ray induced chromosome rearrangement breaks along the polytene chromosomes of Anopheles messeae

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    Pleshkova, G.N. (Tomskij Gosudarstvennyj Univ. (USSR). Nauchno-Issledovatel' skij Inst. Biologii i Biofiziki)

    1983-09-01

    Distribution of chromosomal aberrations localization along polytene chromosomes (aoutosomes) of salivary glands of malarial mosquito. Anopheles messeae is presented. Induced aberrations in F/sub 1/ posterity from X-ray irradiated fecundated females are studied. Points of breaks of inversions and translocations are localized separately. There are no considerable differences in the distribution character of two types of aberrations. Over the length of autosomes the breaks are more frequent in distal halves, their frequency in proximal parts anally in near centromeric regions of chromosomes is reduced. Concentration of breaks in certain ''hot points'' of the chromosomes is pointed out. Comparison of distribution of actual and expected frequencies of break points according to chi/sup 2/ criterion revealed highly fiducial discrepancies, testifying to uneven participation of different regions of chromosomes in aberration formation. Similarities and differences of the data obtained from analogous ones, demonstrated in Drosophila, as well as possible reasons for the distribution unevennes are discussed. On the basis of analysis of intrinsic and literature data a supposition is made that the ''hot points'' (break concentrations) can be considered as localizaion markers of intercalary heterochromatin.

  3. Paternal uniparental isodisomy for chromosome 14 with mosaicism for a supernumerary marker chromosome 14.

    Science.gov (United States)

    Mattes, Joerg; Whitehead, Bruce; Liehr, Thomas; Wilkinson, Ian; Bear, John; Fagan, Kerry; Craven, Paul; Bennetts, Bruce; Edwards, Matthew

    2007-09-15

    Uniparental disomy (UPD) describes the inheritance of two homologous chromosomes from a single parent. Disease phenotypes associated with UPD and chromosomal imprinting, rather than with mutations, include Beckwith-Wiedemann syndrome (paternal UPD11p), Angelman syndrome (paternal UPD15), Prader-Willi syndrome (maternal UPD15), and transient neonatal diabetes (paternal UPD6). Here we report on the first case of paternal uniparental isodisomy of chromosome 14 with a mosaicism for a supernumerary marker chromosome 14. The patient demonstrated a small thorax with a 'coat hanger' shape of the ribs, kyphoscoliosis, hypoplasia of the maxilla and mandible, a broad nasal bridge with anteverted nares, contractures of the wrists with ulnar deviation bilaterally, diastasis recti, and marked muscle hypotonia. Vertical skin creases under the chin and stippled epiphyses of the humeri were features not previously described in patients with paternal UPD14. This case illustrates that as with the finding of an isochromosome, a supernumerary marker chromosome can be an important clue to the presence of UPD14. (c) 2007 Wiley-Liss, Inc.

  4. Chromosomal mapping of repetitive DNAs in Triportheus trifurcatus (Characidae, Characiformes: insights into the differentiation of the Z and W chromosomes.

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    Cassia Fernanda Yano

    Full Text Available Repetitive DNA sequences play an important role in the structural and functional organization of chromosomes, especially in sex chromosome differentiation. The genus Triportheus represents an interesting model for such studies because all of its species analyzed so far contain a ZZ/ZW sex chromosome system. A close relationship has been found between the differentiation of the W chromosome and heterochromatinization, with the involvement of different types of repetitive DNA in this process. This study investigated several aspects of this association in the W chromosome of Triportheus trifurcatus (2 n = 52 chromosomes, including the cytogenetic mapping of repetitive DNAs such as telomeric sequences (TTAGGGn, microsatellites and retrotransposons. A remarkable heterochromatic segment on the W chromosome was observed with a preferential accumulation of (CAC10, (CAG10, (CGG10, (GAA10 and (TA15. The retrotransposons Rex1 and Rex3 showed a general distribution pattern in the chromosomes, and Rex6 showed a different distribution on the W chromosome. The telomeric repeat (TTAGGGn was highly evident in both telomeres of all chromosomes without the occurrence of ITS. Thus, the differentiation of the W chromosome of T. trifurcatus is clearly associated with the formation of heterochromatin and different types of repetitive DNA, suggesting that these elements had a prominent role in this evolutionary process.

  5. Mammalian chromosomes contain cis-acting elements that control replication timing, mitotic condensation, and stability of entire chromosomes.

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    Thayer, Mathew J

    2012-09-01

    Recent studies indicate that mammalian chromosomes contain discrete cis-acting loci that control replication timing, mitotic condensation, and stability of entire chromosomes. Disruption of the large non-coding RNA gene ASAR6 results in late replication, an under-condensed appearance during mitosis, and structural instability of human chromosome 6. Similarly, disruption of the mouse Xist gene in adult somatic cells results in a late replication and instability phenotype on the X chromosome. ASAR6 shares many characteristics with Xist, including random mono-allelic expression and asynchronous replication timing. Additional "chromosome engineering" studies indicate that certain chromosome rearrangements affecting many different chromosomes display this abnormal replication and instability phenotype. These observations suggest that all mammalian chromosomes contain "inactivation/stability centers" that control proper replication, condensation, and stability of individual chromosomes. Therefore, mammalian chromosomes contain four types of cis-acting elements, origins, telomeres, centromeres, and "inactivation/stability centers", all functioning to ensure proper replication, condensation, segregation, and stability of individual chromosomes. Copyright © 2012 WILEY Periodicals, Inc.

  6. Cytomolecular discrimination of the Am chromosomes of Triticum monococcum and the A chromosomes of Triticum aestivum using microsatellite DNA repeats.

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    Megyeri, Mária; Mikó, Péter; Farkas, András; Molnár-Láng, Márta; Molnár, István

    2017-02-01

    The cytomolecular discrimination of the Am- and A-genome chromosomes facilitates the selection of wheat-Triticum monococcum introgression lines. Fluorescence in situ hybridisation (FISH) with the commonly used DNA probes Afa family, 18S rDNA and pSc119.2 showed that the more complex hybridisation pattern obtained in T. monococcum relative to bread wheat made it possible to differentiate the Am and A chromosomes within homoeologous groups 1, 4 and 5. In order to provide additional chromosomal landmarks to discriminate the Am and A chromosomes, the microsatellite repeats (GAA)n, (CAG)n, (CAC)n, (AAC)n, (AGG)n and (ACT)n were tested as FISH probes. These showed that T. monococcum chromosomes have fewer, generally weaker, simple sequence repeat (SSR) signals than the A-genome chromosomes of hexaploid wheat. A differential hybridisation pattern was observed on 6Am and 6A chromosomes with all the SSR probes tested except for the (ACT)n probe. The 2Am and 2A chromosomes were differentiated by the signals given by the (GAA)n, (CAG)n and (AAC)n repeats, while only (GAA)n discriminated the chromosomes 3Am and 3A. Chromosomes 7Am and 7A could be differentiated by the lack of (GAA)n and (AGG)n signals on 7A. As potential landmarks for identifying the Am chromosomes, SSR repeats will facilitate the introgression of T. monococcum chromatin into wheat.

  7. Construction of a genetic map of human chromosome 17 by use of chromosome-mediated gene transfer

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    Xu, Weiming; Gorman, P.A.; Rider, S.H.; Hedge, P.J.; Moore, G.; Prichard, C.; Sheer, D.; Solomon, E. (Imperial Cancer Research Fund, London (England))

    1988-11-01

    The authors used somatic-cell hybrids, containing as their only human genetic contribution part or all of chromosome 17, as donors for chromosome-mediated gene transfer. A total of 54 independent transfectant clones were isolated and analyzed by use of probes or isoenzymes for >20 loci located on chromosome 17. By combining the data from this chromosome-mediated gene transfer transfectant panel, conventional somatic-cell hybrids containing well-defined breaks on chromosome 17, and in situ hybridization they propose the following order for these loci; pter-(TP53-RNP2-D17S1)-(MYH2-MYH1)-D17Z1-CRYB1-(ERBA1-GCSF-NGL)-acute promyelocytic leukemia breakpoint-RNU2-HOX2-(NGFR-COLIAI-MPO)-GAA-UMPH-GHC-TK1-GALK-qter. Using chromosome-mediated gene transfer, they have also regionally localized the random probes D17S6 to D17S19 on chromosome 17.

  8. [Meiotic chromosomes of the tree frog Smilisca baudinii (Anura: Hylidae)].

    Science.gov (United States)

    Hernández-Guzmán, Javier; Arias-Rodriguez, Lenin; Indy, Jeane Rimber

    2011-03-01

    The Mexican tree frog Smilisca baudinii, is a very common frog in Central America. In spite their importance to keep the ecological equilibrium of the rainforest, its biology and genetics are poorly known. In order to contribute with its biological knowledge, we described the typical meiotic karyotype based in standard cytogenetic protocols to specimens collected in Tabasco, Mexico. The study was centered in the analysis of 131 chromosome spreads at meiotic stage from two adults of the species (one female and one male). The metaphase analysis allowed the establishment of the modal haploid number of 1n = 12 bivalent chromosomes. The chromosomic formulae from the haploid bivalent karyotype was integrated by 12 biarmed chromosomes characterized by twelve pairs of metacentric-submetacentric (msm) chromosomes. The meiotic counting gives the idea that diploid chromosome number is integrated by a complement of 2n = 24 biarmed chromosomes. The presence of sex chromosomes from female and male meiotic spreads was not observed. Current results suggest that S. baudinii chromosome structure is well shared among Hylidae family and "B" chromosomes are particular structures that have very important evolutionary consequences in species diversification.

  9. Inheritance of Chromosome-Length Polymorphisms in Coprinus Cinereus

    Science.gov (United States)

    Zolan, M. E.; Heyler, N. K.; Stassen, N. Y.

    1994-01-01

    We have investigated the inheritance of chromosome-length polymorphisms in the basidiomycete Coprinus cinereus. The electrophoretic karyotypes of interfertile strains of C. cinereus are strikingly different, and crosses between strains with different karyotypes yield progeny with chromosomes of new sizes. Repeated backcrossing of a mutant to one parent often stabilizes the mutant chromosome at a unique size; this then becomes a chromosome-length polymorphism marker for that mutant gene. A comparison of mutant strains, their wild-type progenitor, and backcrossed strains revealed that these marker chromosomes are not caused by the initial mutagenic treatment and are found only in progeny of crosses between strains with polymorphic chromosomes. Thus, they are most likely formed by meiotic recombination. For the rad12 gene, the marker chromosome can further recombine to become the size of the homolog of the backcross parent. For the rad3 gene, both ectopic and homologous recombination events are likely involved in the generation of the marker chromosomes. As predicted by a recombination model, a cross to a new wild-type parent can change the size of a mutant marker chromosome. Therefore, changes in chromosome length are a common and prominent feature of the genome of this sexual fungus, and a variety of karyotypes is tolerated by the organism. PMID:7914506

  10. Pathogenesis of vestibular schwannoma in ring chromosome 22

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    Debiec-Rychter Maria

    2009-09-01

    Full Text Available Abstract Background Ring chromosome 22 is a rare human constitutional cytogenetic abnormality. Clinical features of neurofibromatosis type 1 and 2 as well as different tumour types have been reported in patients with ring chromosome 22. The pathogenesis of these tumours is not always clear yet. Methods We report on a female patient with a ring chromosome 22 presenting with severe mental retardation, autistic behaviour, café-au-lait macules and facial dysmorphism. Peripheral blood lymphocytes were karyotyped and array CGH was performed on extracted DNA. At the age of 20 years she was diagnosed with a unilateral vestibular schwannoma. Tumour cells were analyzed by karyotyping, array CGH and NF2 mutation analysis. Results Karyotype on peripheral blood lymphocytes revealed a ring chromosome 22 in all analyzed cells. A 1 Mb array CGH experiment on peripheral blood DNA showed a deletion of 5 terminal clones on the long arm of chromosome 22. Genetic analysis of vestibular schwannoma tissue revealed loss of the ring chromosome 22 and a somatic second hit in the NF2 gene on the remaining chromosome 22. Conclusion We conclude that tumours can arise by the combination of loss of the ring chromosome and a pathogenic NF2 mutation on the remaining chromosome 22 in patients with ring chromosome 22. Our findings indicate that patients with a ring 22 should be monitored for NF2-related tumours starting in adolescence.

  11. Roles of the Y chromosome genes in human cancers

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    Tatsuo Kido

    2015-06-01

    Full Text Available Male and female differ genetically by their respective sex chromosome composition, that is, XY as male and XX as female. Although both X and Y chromosomes evolved from the same ancestor pair of autosomes, the Y chromosome harbors male-specific genes, which play pivotal roles in male sex determination, germ cell differentiation, and masculinization of various tissues. Deletions or translocation of the sex-determining gene, SRY, from the Y chromosome causes disorders of sex development (previously termed as an intersex condition with dysgenic gonads. Failure of gonadal development results not only in infertility, but also in increased risks of germ cell tumor (GCT, such as gonadoblastoma and various types of testicular GCT. Recent studies demonstrate that either loss of Y chromosome or ectopic expression of Y chromosome genes is closely associated with various male-biased diseases, including selected somatic cancers. These observations suggest that the Y-linked genes are involved in male health and diseases in more frequently than expected. Although only a small number of protein-coding genes are present in the male-specific region of Y chromosome, the impacts of Y chromosome genes on human diseases are still largely unknown, due to lack of in vivo models and differences between the Y chromosomes of human and rodents. In this review, we highlight the involvement of selected Y chromosome genes in cancer development in men.

  12. Origin of B chromosomes in Characidium alipioi (Characiformes, Crenuchidae and its relationship with supernumerary chromosomes in other Characidium species

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    Érica Alves Serrano

    2017-01-01

    Full Text Available B chromosomes are apparently dispensable components found in the genomes of many species that are mainly composed of repetitive DNA sequences. Among the numerous questions concerning B chromosomes, the origin of these elements has been widely studied. To date, supernumerary chromosomes have been identified in approximately 60 species of fish, including species of the genus Characidium Reinhardt, 1867 in which these elements appear to have independently originated. In this study, we used molecular cytogenetic techniques to investigate the origin of B chromosomes in a population of Characidium alipioi Travassos, 1955 and determine their relationship with the extra chromosomes of other species of the genus. The results showed that the B chromosomes of C. alipioi had an intraspecific origin, apparently originated independently in relation to the B chromosomes of C. gomesi Travassos, 1956 C. pterostictum Gomes, 1947 and C. oiticicai Travassos, 1967, since they do not share specific DNA sequences, as well as their possible ancestral chromosomes and belong to different phylogenetic clades. The shared sequences between the supernumerary chromosomes and the autosommal sm pair indicate the origin of these chromosomes.

  13. Modeling Meiotic Chromosomes Indicates a Size Dependent Contribution of Telomere Clustering and Chromosome Rigidity to Homologue Juxtaposition

    Science.gov (United States)

    Penfold, Christopher A.; Brown, Paul E.; Lawrence, Neil D.; Goldman, Alastair S. H.

    2012-01-01

    Meiosis is the cell division that halves the genetic component of diploid cells to form gametes or spores. To achieve this, meiotic cells undergo a radical spatial reorganisation of chromosomes. This reorganisation is a prerequisite for the pairing of parental homologous chromosomes and the reductional division, which halves the number of chromosomes in daughter cells. Of particular note is the change from a centromere clustered layout (Rabl configuration) to a telomere clustered conformation (bouquet stage). The contribution of the bouquet structure to homologous chromosome pairing is uncertain. We have developed a new in silico model to represent the chromosomes of Saccharomyces cerevisiae in space, based on a worm-like chain model constrained by attachment to the nuclear envelope and clustering forces. We have asked how these constraints could influence chromosome layout, with particular regard to the juxtaposition of homologous chromosomes and potential nonallelic, ectopic, interactions. The data support the view that the bouquet may be sufficient to bring short chromosomes together, but the contribution to long chromosomes is less. We also find that persistence length is critical to how much influence the bouquet structure could have, both on pairing of homologues and avoiding contacts with heterologues. This work represents an important development in computer modeling of chromosomes, and suggests new explanations for why elucidating the functional significance of the bouquet by genetics has been so difficult. PMID:22570605

  14. Interchromosomal duplications on the Bactrocera oleae Y chromosome imply a distinct evolutionary origin of the sex chromosomes compared to Drosophila.

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    Paolo Gabrieli

    Full Text Available BACKGROUND: Diptera have an extraordinary variety of sex determination mechanisms, and Drosophila melanogaster is the paradigm for this group. However, the Drosophila sex determination pathway is only partially conserved and the family Tephritidae affords an interesting example. The tephritid Y chromosome is postulated to be necessary to determine male development. Characterization of Y sequences, apart from elucidating the nature of the male determining factor, is also important to understand the evolutionary history of sex chromosomes within the Tephritidae. We studied the Y sequences from the olive fly, Bactrocera oleae. Its Y chromosome is minute and highly heterochromatic, and displays high heteromorphism with the X chromosome. METHODOLOGY/PRINCIPAL FINDINGS: A combined Representational Difference Analysis (RDA and fluorescence in-situ hybridization (FISH approach was used to investigate the Y chromosome to derive information on its sequence content. The Y chromosome is strewn with repetitive DNA sequences, the majority of which are also interdispersed in the pericentromeric regions of the autosomes. The Y chromosome appears to have accumulated small and large repetitive interchromosomal duplications. The large interchromosomal duplications harbour an importin-4-like gene fragment. Apart from these importin-4-like sequences, the other Y repetitive sequences are not shared with the X chromosome, suggesting molecular differentiation of these two chromosomes. Moreover, as the identified Y sequences were not detected on the Y chromosomes of closely related tephritids, we can infer divergence in the repetitive nature of their sequence contents. CONCLUSIONS/SIGNIFICANCE: The identification of Y-linked sequences may tell us much about the repetitive nature, the origin and the evolution of Y chromosomes. We hypothesize how these repetitive sequences accumulated and were maintained on the Y chromosome during its evolutionary history. Our data

  15. Interchromosomal Duplications on the Bactrocera oleae Y Chromosome Imply a Distinct Evolutionary Origin of the Sex Chromosomes Compared to Drosophila

    Science.gov (United States)

    Gabrieli, Paolo; Gomulski, Ludvik M.; Bonomi, Angelica; Siciliano, Paolo; Scolari, Francesca; Franz, Gerald; Jessup, Andrew; Malacrida, Anna R.; Gasperi, Giuliano

    2011-01-01

    Background Diptera have an extraordinary variety of sex determination mechanisms, and Drosophila melanogaster is the paradigm for this group. However, the Drosophila sex determination pathway is only partially conserved and the family Tephritidae affords an interesting example. The tephritid Y chromosome is postulated to be necessary to determine male development. Characterization of Y sequences, apart from elucidating the nature of the male determining factor, is also important to understand the evolutionary history of sex chromosomes within the Tephritidae. We studied the Y sequences from the olive fly, Bactrocera oleae. Its Y chromosome is minute and highly heterochromatic, and displays high heteromorphism with the X chromosome. Methodology/Principal Findings A combined Representational Difference Analysis (RDA) and fluorescence in-situ hybridization (FISH) approach was used to investigate the Y chromosome to derive information on its sequence content. The Y chromosome is strewn with repetitive DNA sequences, the majority of which are also interdispersed in the pericentromeric regions of the autosomes. The Y chromosome appears to have accumulated small and large repetitive interchromosomal duplications. The large interchromosomal duplications harbour an importin-4-like gene fragment. Apart from these importin-4-like sequences, the other Y repetitive sequences are not shared with the X chromosome, suggesting molecular differentiation of these two chromosomes. Moreover, as the identified Y sequences were not detected on the Y chromosomes of closely related tephritids, we can infer divergence in the repetitive nature of their sequence contents. Conclusions/Significance The identification of Y-linked sequences may tell us much about the repetitive nature, the origin and the evolution of Y chromosomes. We hypothesize how these repetitive sequences accumulated and were maintained on the Y chromosome during its evolutionary history. Our data reinforce the idea that the

  16. Cell division control by the Chromosomal Passenger Complex

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    Waal, Maike S. van der; Hengeveld, Rutger C.C.; Horst, Armando van der; Lens, Susanne M.A., E-mail: s.m.a.lens@umcutrecht.nl

    2012-07-15

    The Chromosomal Passenger Complex (CPC) consisting of Aurora B kinase, INCENP, Survivin and Borealin, is essential for genomic stability by controlling multiple processes during both nuclear and cytoplasmic division. In mitosis it ensures accurate segregation of the duplicated chromosomes by regulating the mitotic checkpoint, destabilizing incorrectly attached spindle microtubules and by promoting the axial shortening of chromosomal arms in anaphase. During cytokinesis the CPC most likely prevents chromosome damage by imposing an abscission delay when a chromosome bridge connects the two daughter cells. Moreover, by controlling proper cytoplasmic division, the CPC averts tetraploidization. This review describes recent insights on how the CPC is capable of conducting its various functions in the dividing cell to ensure chromosomal stability.

  17. Genetic modification of mammalian genome at chromosome level

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    OLEG L. SEROV

    2000-09-01

    Full Text Available The review is concerned with a progress in genetic modification of a mammalian genome in vitro and in vivo at chromosomal level. Recently three new approaches for the chromosome biotechnology have been developed: Using Cre/loxP-system a researcher is able to produce targeted rearrangements of whole chromosomes or their segments or particular genes within the genome, and therefore to modify the set, position and copy number of the endogenous elements of the genome. Mammalian artificial chromosomes (MACs provide a possibility to introduce into genome relatively large segments of alien chromosome material, either artificially constructed or derived from the genome of different species. Using ES-somatic cell hybrids allows to transfer whole chromosomes or their fragments between different genomes within and between species. Advantages and limitations of these approaches are discussed.

  18. Technical Review: Cytogenetic Tools for Studying Mitotic Chromosomes.

    Science.gov (United States)

    Bačovský, Václaclav; Hobza, Roman; Vyskot, Boris

    2018-01-01

    Significant advances in chromosome preparation and other techniques have greatly increased the potential of plant cytogenetics in recent years. Increase in longitudinal resolution using DNA extended fibers as well as new developments in imaging and signal amplification technologies have enhanced the ability of FISH to detect small gene targets. The combination of fluorescence in situ hybridization with immunocytochemistry allows the investigation of cell events, chromosomal rearrangements and chromatin features typical for plant nuclei. Chromosome manipulation techniques using microdissection and flow sorting have accelerated the analysis of complex plant genomes. Together, the different cytogenetic approaches are invaluable for the unravelling of detailed structures of plant chromosomes, which are of utmost importance for the study of genome properties, DNA replication and gene regulation. In this technical review, different cytogenetic approaches are discussed for the analysis of plant chromosomes, with a focus on mitotic chromosomes.

  19. The DNA sequence and analysis of human chromosome 14.

    Science.gov (United States)

    Heilig, Roland; Eckenberg, Ralph; Petit, Jean-Louis; Fonknechten, Núria; Da Silva, Corinne; Cattolico, Laurence; Levy, Michaël; Barbe, Valérie; de Berardinis, Véronique; Ureta-Vidal, Abel; Pelletier, Eric; Vico, Virginie; Anthouard, Véronique; Rowen, Lee; Madan, Anup; Qin, Shizhen; Sun, Hui; Du, Hui; Pepin, Kymberlie; Artiguenave, François; Robert, Catherine; Cruaud, Corinne; Brüls, Thomas; Jaillon, Olivier; Friedlander, Lucie; Samson, Gaelle; Brottier, Philippe; Cure, Susan; Ségurens, Béatrice; Anière, Franck; Samain, Sylvie; Crespeau, Hervé; Abbasi, Nissa; Aiach, Nathalie; Boscus, Didier; Dickhoff, Rachel; Dors, Monica; Dubois, Ivan; Friedman, Cynthia; Gouyvenoux, Michel; James, Rose; Madan, Anuradha; Mairey-Estrada, Barbara; Mangenot, Sophie; Martins, Nathalie; Ménard, Manuela; Oztas, Sophie; Ratcliffe, Amber; Shaffer, Tristan; Trask, Barbara; Vacherie, Benoit; Bellemere, Chadia; Belser, Caroline; Besnard-Gonnet, Marielle; Bartol-Mavel, Delphine; Boutard, Magali; Briez-Silla, Stéphanie; Combette, Stephane; Dufossé-Laurent, Virginie; Ferron, Carolyne; Lechaplais, Christophe; Louesse, Claudine; Muselet, Delphine; Magdelenat, Ghislaine; Pateau, Emilie; Petit, Emmanuelle; Sirvain-Trukniewicz, Peggy; Trybou, Arnaud; Vega-Czarny, Nathalie; Bataille, Elodie; Bluet, Elodie; Bordelais, Isabelle; Dubois, Maria; Dumont, Corinne; Guérin, Thomas; Haffray, Sébastien; Hammadi, Rachid; Muanga, Jacqueline; Pellouin, Virginie; Robert, Dominique; Wunderle, Edith; Gauguet, Gilbert; Roy, Alice; Sainte-Marthe, Laurent; Verdier, Jean; Verdier-Discala, Claude; Hillier, LaDeana; Fulton, Lucinda; McPherson, John; Matsuda, Fumihiko; Wilson, Richard; Scarpelli, Claude; Gyapay, Gábor; Wincker, Patrick; Saurin, William; Quétier, Francis; Waterston, Robert; Hood, Leroy; Weissenbach, Jean

    2003-02-06

    Chromosome 14 is one of five acrocentric chromosomes in the human genome. These chromosomes are characterized by a heterochromatic short arm that contains essentially ribosomal RNA genes, and a euchromatic long arm in which most, if not all, of the protein-coding genes are located. The finished sequence of human chromosome 14 comprises 87,410,661 base pairs, representing 100% of its euchromatic portion, in a single continuous segment covering the entire long arm with no gaps. Two loci of crucial importance for the immune system, as well as more than 60 disease genes, have been localized so far on chromosome 14. We identified 1,050 genes and gene fragments, and 393 pseudogenes. On the basis of comparisons with other vertebrate genomes, we estimate that more than 96% of the chromosome 14 genes have been annotated. From an analysis of the CpG island occurrences, we estimate that 70% of these annotated genes are complete at their 5' end.

  20. The Tubulin Code: A Navigation System for Chromosomes during Mitosis.

    Science.gov (United States)

    Barisic, Marin; Maiato, Helder

    2016-10-01

    Before chromosomes segregate during mitosis in metazoans, they align at the cell equator by a process known as chromosome congression. This is in part mediated by the coordinated activities of kinetochore motors with opposite directional preferences that transport peripheral chromosomes along distinct spindle microtubule populations. Because spindle microtubules are all made from the same α/β-tubulin heterodimers, a critical longstanding question has been how chromosomes are guided to specific locations during mitosis. This implies the existence of spatial cues/signals on specific spindle microtubules that are read by kinetochore motors on chromosomes and ultimately indicate the way towards the equator. Here, we discuss the emerging concept that tubulin post-translational modifications (PTMs), as part of the so-called tubulin code, work as a navigation system for kinetochore-based chromosome motility during early mitosis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. New native South American Y chromosome lineages.

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    Jota, Marilza S; Lacerda, Daniela R; Sandoval, José R; Vieira, Pedro Paulo R; Ohasi, Dominique; Santos-Júnior, José E; Acosta, Oscar; Cuellar, Cinthia; Revollo, Susana; Paz-Y-Miño, Cesar; Fujita, Ricardo; Vallejo, Gustavo A; Schurr, Theodore G; Tarazona-Santos, Eduardo M; Pena, Sergio Dj; Ayub, Qasim; Tyler-Smith, Chris; Santos, Fabrício R

    2016-07-01

    Many single-nucleotide polymorphisms (SNPs) in the non-recombining region of the human Y chromosome have been described in the last decade. High-coverage sequencing has helped to characterize new SNPs, which has in turn increased the level of detail in paternal phylogenies. However, these paternal lineages still provide insufficient information on population history and demography, especially for Native Americans. The present study aimed to identify informative paternal sublineages derived from the main founder lineage of the Americas-haplogroup Q-L54-in a sample of 1841 native South Americans. For this purpose, we used a Y-chromosomal genotyping multiplex platform and conventional genotyping methods to validate 34 new SNPs that were identified in the present study by sequencing, together with many Y-SNPs previously described in the literature. We updated the haplogroup Q phylogeny and identified two new Q-M3 and three new Q-L54*(xM3) sublineages defined by five informative SNPs, designated SA04, SA05, SA02, SA03 and SA29. Within the Q-M3, sublineage Q-SA04 was mostly found in individuals from ethnic groups belonging to the Tukanoan linguistic family in the northwest Amazon, whereas sublineage Q-SA05 was found in Peruvian and Bolivian Amazon ethnic groups. Within Q-L54*, the derived sublineages Q-SA03 and Q-SA02 were exclusively found among Coyaima individuals (Cariban linguistic family) from Colombia, while Q-SA29 was found only in Maxacali individuals (Jean linguistic family) from southeast Brazil. Furthermore, we validated the usefulness of several published SNPs among indigenous South Americans. This new Y chromosome haplogroup Q phylogeny offers an informative paternal genealogy to investigate the pre-Columbian history of South America.Journal of Human Genetics advance online publication, 31 March 2016; doi:10.1038/jhg.2016.26.

  2. Afghanistan from a Y-chromosome perspective.

    Science.gov (United States)

    Lacau, Harlette; Gayden, Tenzin; Regueiro, Maria; Chennakrishnaiah, Shilpa; Bukhari, Areej; Underhill, Peter A; Garcia-Bertrand, Ralph L; Herrera, Rene J

    2012-10-01

    Central Asia has served as a corridor for human migrations providing trading routes since ancient times. It has functioned as a conduit connecting Europe and the Middle East with South Asia and far Eastern civilizations. Therefore, the study of populations in this region is essential for a comprehensive understanding of early human dispersal on the Eurasian continent. Although Y- chromosome distributions in Central Asia have been widely surveyed, present-day Afghanistan remains poorly characterized genetically. The present study addresses this lacuna by analyzing 190 Pathan males from Afghanistan using high-resolution Y-chromosome binary markers. In addition, haplotype diversity for its most common lineages (haplogroups R1a1a*-M198 and L3-M357) was estimated using a set of 15 Y-specific STR loci. The observed haplogroup distribution suggests some degree of genetic isolation of the northern population, likely due to the Hindu Kush mountain range separating it from the southern Afghans who have had greater contact with neighboring Pathans from Pakistan and migrations from the Indian subcontinent. Our study demonstrates genetic similarities between Pathans from Afghanistan and Pakistan, both of which are characterized by the predominance of haplogroup R1a1a*-M198 (>50%) and the sharing of the same modal haplotype. Furthermore, the high frequencies of R1a1a-M198 and the presence of G2c-M377 chromosomes in Pathans might represent phylogenetic signals from Khazars, a common link between Pathans and Ashkenazi groups, whereas the absence of E1b1b1a2-V13 lineage does not support their professed Greek ancestry.

  3. Diagnostic Role of Chromosomal Instability in Melanoma

    Directory of Open Access Journals (Sweden)

    Nitika Dabas

    2012-01-01

    Full Text Available Early diagnosis gives melanoma patients the best chance for long term survival. However discrimination of an early melanoma from an unusual/atypical benign nevus can represent a significant challenge. There are no current pathological markers to definitively define malignant potential in these indeterminate lesions. Thus, there is a need for improved diagnostic tools. Chromosomal instability (CIN is a hallmark of cancer and is markedly prevalent in melanoma. Advances in genomics have opened the door for the development of molecular tools to better segregate benign and malignant lesions. This paper focuses on CIN in melanoma and the role of current diagnostic approaches.

  4. Chromosome analysis of three species of Myoxidae

    Directory of Open Access Journals (Sweden)

    Maria Vittoria Civitelli

    1995-05-01

    Full Text Available Abstract Karyotype analysis was carried out on three species of dormice: Myoxus glis, 4 populations from Northern and Southern Italy and from Turkey; Dryomys nitedula, 4 populations from Northern and Southern Italy, from Israel and from Turkey; Myomimus roachi, 1 specimen from Turkey. Myoxus glis shows 2n=62; comparison of our specimens from different localities shows complete correspondence between karyotypes, both for the autosomes and the heterochromosomes. Dryomys nitedula shows 2n=48. All populations we studied, show the same karyotypic pattern, except for the NOR-bearing chromosomes. Myomimus roachi, here studied for the first time, shows 2n=44. All the autosomes are biarmed of decreasing size. The X-chromosome is a medium size metacentric, while the Y-chromosome is the smallest one. All the three species we studied, show one pair of NOR-bearing chromosomes, Ag-NORs always correspond to the secondary constriction. Differences in the fundamental number and in heterochromosome morphology, have been observed by other authors, in different European populations. This variability is analysed and discussed. Riassunto Analisi cromosomica in tre specie di Myoxidae - L'analisi cromosomica è stata condotta su popolazioni europee di tre specie di Myoxidae: Myoxus glis, 4 popolazioni provenienti dal Nord e Sud Italia, e dalla Turchia; Dryomys nitedula, 4 popolazioni provenienti dal Nord e Sud Italia, da Israele e dalla Turchia; Myomimus roachi, 1 esemplare, proveniente dalla Turchia. Myoxus glis presenta 2n=62. Gli esemplari, provenienti dalle diverse popolazioni, mostrano corrispondenza nella morfologia sia degli autosomi che degli eterocromosomi. Dryomys nitedula presenta 2n=48. La morfologia dei cromosomi nei cariotipi appare corrispondente mentre diversa è la localizzazione degli Ag-NOR.

  5. Chromosomes in the flow to simplify genome analysis

    Czech Academy of Sciences Publication Activity Database

    Doležel, Jaroslav; Vrána, Jan; Šafář, Jan; Bartoš, Jan; Kubaláková, Marie; Šimková, Hana

    2012-01-01

    Roč. 12, č. 3 (2012), s. 397-416 ISSN 1438-793X R&D Projects: GA ČR GAP501/10/1740; GA ČR GAP501/10/1778 Institutional research plan: CEZ:AV0Z50380511 Keywords : Chromosome sorting * Chromosome-specific BAC libraries * Chromosome sequencing Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.292, year: 2012

  6. Identification of Pneumocystis carinii chromosomes and mapping of five genes

    DEFF Research Database (Denmark)

    Lundgren, B; Cotton, R; Lundgren, J D

    1990-01-01

    Pulsed field gel electrophoresis was used to identify the chromosome-size DNA of Pneumocystis carinii, a major pathogen of immunocompromised patients. Thirteen chromosomes of rodent Pneumocystis carinii, ranging in size from 300 to 700 kilobases (kb), were identified. The minimum genome size for ......, and thymidylate synthase were mapped to single chromosomes of approximately 650, 590, 550, 460, and 350 kb, respectively. Hybridization studies further confirmed the genetic heterogeneity of P. carinii....

  7. Nonrandom involvement of chromosomal segments in human hematologic malignancies

    Energy Technology Data Exchange (ETDEWEB)

    Rowley, J. D.

    1977-01-01

    The consistent occurrence of nonrandom chromosome changes in human malignancies suggests that they are not trivial epiphenomena. Whereas we do not understand their significance at present, one possible role which they may fulfill is to provide the chromosomally aberrant cells with a proliferative advantage as the result of alteration of the number and/or location of genes related to nucleic acid biosynthesis. It would be expected that the proliferative advantage provided by various chromosome aberrations differs in patients with different genetic constitutions.

  8. Human ferritin gene is assigned to chromosome 19.

    OpenAIRE

    Caskey, J H; Jones, C; Miller, Y E; Seligman, P A

    1983-01-01

    Ferritin is the intracellular iron storage protein. Tissue ferritin stores are markedly increased in hemochromatosis, a disease of iron overload that has been linked to chromosome 6. In order to provide further information concerning the genetics of ferritin synthesis and to determine if the structural gene for ferritin was on chromosome 6, studies were performed to identify the human chromosome that contains the ferritin gene. Ferritin immunoassays were performed on extracts of Chinese hamst...

  9. Development of new postnatal diagnostic methods for chromosome disorders.

    Science.gov (United States)

    Shaffer, Lisa G; Bejjani, Bassem A

    2011-04-01

    Chromosome imbalances are the leading cause of intellectual and developmental disabilities in the population. This paper reviews the current methods used to diagnose chromosome abnormalities in children including karyotyping, fluorescence in situ hybridization and microarray technologies. Advances in molecular cytogenetics, especially with the use of microarrays, have substantially increased the detection of chromosome abnormalities in children with disabilities and congenital anomalies above that achievable with conventional cytogenetic banding and light microscopy. Copyright © 2010 Elsevier Ltd. All rights reserved.

  10. Multifork chromosome replication in slow-growing bacteria

    OpenAIRE

    Damian Trojanowski; Joanna Hołówka; Katarzyna Ginda; Dagmara Jakimowicz; Jolanta Zakrzewska-Czerwińska

    2017-01-01

    The growth rates of bacteria must be coordinated with major cell cycle events, including chromosome replication. When the doubling time (Td) is shorter than the duration of chromosome replication (C period), a new round of replication begins before the previous round terminates. Thus, newborn cells inherit partially duplicated chromosomes. This phenomenon, which is termed multifork replication, occurs among fast-growing bacteria such as Escherichia coli and Bacillus subtilis. In contrast, it ...

  11. The DNA sequence and analysis of human chromosome 13

    OpenAIRE

    Dunham, A.; Matthews, L. H.; Burton, J.; Ashurst, J. L.; Howe, K. L.; Ashcroft, K. J.; Beare, D. M.; Burford, D. C.; Hunt, S. E.; Griffiths-Jones, S.; Jones, M. C.; Keenan, S. J.; Oliver, K.; Scott, C. E.; Ainscough, R.

    2004-01-01

    Chromosome 13 is the largest acrocentric human chromosome. It carries genes involved in cancer including the breast cancer type 2 (BRCA2) and retinoblastoma (RB1) genes, is frequently rearranged in B-cell chronic lymphocytic leukaemia, and contains the DAOA locus associated with bipolar disorder and schizophrenia. We describe completion and analysis of 95.5 megabases (Mb) of sequence from chromosome 13, which contains 633 genes and 296 pseudogenes. We estimate that more than 95.4% of the prot...

  12. Forensic use of Y-chromosome DNA: a general overview

    OpenAIRE

    Kayser, Manfred

    2017-01-01

    textabstractThe male-specific part of the human Y chromosome is widely used in forensic DNA analysis, particularly in cases where standard autosomal DNA profiling is not informative. A Y-chromosomal gene fragment is applied for inferring the biological sex of a crime scene trace donor. Haplotypes composed of Y-chromosomal short tandem repeat polymorphisms (Y-STRs) are used to characterise paternal lineages of unknown male trace donors, especially suitable when males and females have contribut...

  13. Natural triploidy in Leporinus cf. elongatus bearing sex chromosomes

    Directory of Open Access Journals (Sweden)

    Wagner Franco Molina

    2007-01-01

    Full Text Available Although several cases of natural triploidy in fish have already been described, spontaneous polyploidy in species with differentiated sex chromosomes are rare. We report the occurrence of a triploid fish (3n = 81 Leporinus cf. elongatus, a species characterized by a highly differentiated ZZ/ZW sex chromosome system, from the São Francisco river. The occurrence of a ZZZ triploid adult indicates the viability of this chromosome constitution in this fish.

  14. Constitutive heterochromatin in chromosomes of duck hybrids and goose hybrids.

    Science.gov (United States)

    Wójcik, E; Smalec, E

    2017-01-01

    Constitutive heterochromatin is a highly condensed fraction of chromatin in chromosomes. It is characterized by a high degree of polymorphism. Heterochromatin is located in the centromeric, telomeric, and interstitial parts of chromosomes. We used the CBG ( C: banding using B: arium hydroxide by G: iemsa) staining technique to identify heterochromatin in chromosomes. Analysis of karyotypes of F1 hybrids resulting from intergeneric hybridization of ducks (A. platyrhynchos × C. moschata) and interspecific crosses of geese (A. anser × A. cygnoides) were used to compare the karyotypes of 2 species of duck and 2 species of geese, as well as to compare the hybrids with the parent species. The localization of C-bands and their size were determined. In the duck hybrid, greater amounts of heterochromatin were noted in the homologous chromosomes from the duck A. platyrhynchos than in the chromosomes from the duck C. moschata. In the goose hybrid more heterochromatin was observed in the homologous chromosomes from the goose A. cygnoides than in the chromosomes from the goose A. anser. Comparison of chromosomes from the duck hybrid with chromosomes of the ducks A. platyrhynchos and C. moschata revealed nearly twice as much constitutive heterochromatin in the chromosomes of the hybrid. When chromosomes from the goose hybrid were compared with those of the geese A. anser and A. cygnoides, differences in the average content of heterochromatin were observed on only a few chromosomes. © 2016 Poultry Science Association Inc.

  15. Female chromosome X mosaicism is age-related and preferentially affects the inactivated X chromosome

    DEFF Research Database (Denmark)

    Machiela, Mitchell J; Zhou, Weiyin; Karlins, Eric

    2016-01-01

    To investigate large structural clonal mosaicism of chromosome X, we analysed the SNP microarray intensity data of 38,303 women from cancer genome-wide association studies (20,878 cases and 17,425 controls) and detected 124 mosaic X events >2 Mb in 97 (0.25%) women. Here we show rates for X-chrom...

  16. A high-resolution radiation hybrid map of chicken chromosome 5 and comparison with human chromosomes

    Directory of Open Access Journals (Sweden)

    Milan Denis

    2004-09-01

    Full Text Available Abstract Background The resolution of radiation hybrid (RH maps is intermediate between that of the genetic and BAC (Bacterial Artificial Chromosome contig maps. Moreover, once framework RH maps of a genome have been constructed, a quick location of markers by simple PCR on the RH panel is possible. The chicken ChickRH6 panel recently produced was used here to construct a high resolution RH map of chicken GGA5. To confirm the validity of the map and to provide valuable comparative mapping information, both markers from the genetic map and a high number of ESTs (Expressed Sequence Tags were used. Finally, this RH map was used for testing the accuracy of the chicken genome assembly for chromosome 5. Results A total of 169 markers (21 microsatellites and 148 ESTs were typed on the ChickRH6 RH panel, of which 134 were assigned to GGA5. The final map is composed of 73 framework markers extending over a 1315.6 cR distance. The remaining 61 markers were placed alongside the framework markers within confidence intervals. Conclusion The high resolution framework map obtained in this study has markers covering the entire chicken chromosome 5 and reveals the existence of a high number of rearrangements when compared to the human genome. Only two discrepancies were observed in relation to the sequence assembly recently reported for this chromosome.

  17. A high-resolution radiation hybrid map of chicken chromosome 5 and comparison with human chromosomes

    NARCIS (Netherlands)

    Pitel, F.; Abasht, B.; Morrison, M.; Crooijmans, R.P.M.A.; Vignoles, F.; Leroux, S.; Feve, K.; Bardes, S.; Milan, D.; Lagarrigue, S.; Groenen, M.A.M.; Douaire, M.; Vignal, A.

    2004-01-01

    Background - The resolution of radiation hybrid (RH) maps is intermediate between that of the genetic and BAC (Bacterial Artificial Chromosome) contig maps. Moreover, once framework RH maps of a genome have been constructed, a quick location of markers by simple PCR on the RH panel is possible. The

  18. Different numbers of rye B chromosomes induce identical compaction changes in distinct A chromosome domains.

    Science.gov (United States)

    Delgado, M; Caperta, A; Ribeiro, T; Viegas, W; Jones, R N; Morais-Cecílio, L

    2004-01-01

    In rye each B chromosome (B) represents 5.5% of the diploid A genome. Rye Bs have several nuclear to whole plant effects although they seem to bear no genes except for the ones that lead to their maintenance within a population. In this context, and considering that rye Bs are enriched in repetitive non-coding regions that build up heterochromatin (het), we investigated the influence of Bs on the organization of two chromatin fractions, namely the ribosomal DNA (facultative het) and satellite (non-het) domain of rye chromosome 1 by silver staining on root tip metaphase cells. The results show that rye Bs cause condensation both in the NOR and in the chromosome 1 satellite domain. Since the silver staining technique used is indicative of the transcriptional activity of the NORs, the condensation observed at those loci demonstrates that the rRNA gene arrays are down-regulated in the presence of Bs, regardless of their number per individual. Furthermore, the organizational changes of metaphase NORs find parallel with the interphase organization of ribosomal chromatin, since the frequency of cells with intranucleolar condensed rDNA regions increases drastically and nuclear matrix attachment pattern is altered in the presence of the Bs. Our results show an identical effect of the Bs on the organization of two distinct chromosome domains displaying a presence/absence dichotomy. Copyright 2004 S. Karger AG, Basel

  19. QTL for body composition on chromosome 7 detected using a chromosome substitution mouse strain.

    Science.gov (United States)

    Reed, Danielle R; McDaniel, Amanda H; Avigdor, Mauricio; Bachmanov, Alexander A

    2008-02-01

    Previous studies in mice have detected quantitative trait loci (QTLs) on chromosome 7 that affect body composition. As a step toward identifying the responsible genes, we compared a chromosome 7 substitution strain C57BL/6J-Chr7(129S1/SvImJ)/Na (CSS-7) to its host (C57BL/6J) strain. Fourteen-week-old mice were measured for body size (weight, length), organ weight (brain, heart, liver, kidneys, and spleen), body and bone composition (fat and lean weight; bone area, mineral content, and density), and individual adipose depot weights (gonadal, retroperitoneal, mesenteric, inguinal, and subscapular). Differences between the CSS-7 strain and the host strain were interpreted as evidence for the presence of one or more QTLs on chromosome 7. Using this criterion, we detected QTLs for body weight, bone area, bone mineral content, brain, and heart weight, most adipose depot weights and some indices of fatness. A few strain differences were more pronounced in males (e.g., most adiposity measures) and others were more pronounced in females (e.g., bone area). QTLs for body length, lean weight, bone mineral density, and kidney, spleen, and liver weight were not detected. This study found several associations that suggest one or more QTLs specific to the weight of select tissues and organs exist on mouse chromosome 7. Because these loci are detectable on a fixed and uniform genetic background, they are reasonable targets for high-resolution mapping and gene identification using a congenic approach.

  20. Quantitative analysis of chromosome condensation in fission yeast.

    Science.gov (United States)

    Petrova, Boryana; Dehler, Sascha; Kruitwagen, Tom; Hériché, Jean-Karim; Miura, Kota; Haering, Christian H

    2013-03-01

    Chromosomes undergo extensive conformational rearrangements in preparation for their segregation during cell divisions. Insights into the molecular mechanisms behind this still poorly understood condensation process require the development of new approaches to quantitatively assess chromosome formation in vivo. In this study, we present a live-cell microscopy-based chromosome condensation assay in the fission yeast Schizosaccharomyces pombe. By automatically tracking the three-dimensional distance changes between fluorescently marked chromosome loci at high temporal and spatial resolution, we analyze chromosome condensation during mitosis and meiosis and deduct defined parameters to describe condensation dynamics. We demonstrate that this method can determine the contributions of condensin, topoisomerase II, and Aurora kinase to mitotic chromosome condensation. We furthermore show that the assay can identify proteins required for mitotic chromosome formation de novo by isolating mutants in condensin, DNA polymerase ε, and F-box DNA helicase I that are specifically defective in pro-/metaphase condensation. Thus, the chromosome condensation assay provides a direct and sensitive system for the discovery and characterization of components of the chromosome condensation machinery in a genetically tractable eukaryote.