Showing papers on "Karyotype published in 1984"

Cloning of the chromosome breakpoint of neoplastic B cells with the t(14;18) chromosome translocation

Abstract: From an acute B-cell leukemia cell line, a DNA probe was obtained that was specific for chromosome 18 and flanked the heavy chain joining region of the immunoglobulin heavy chain locus on chromosome 14. This probe detected rearrangement of the homologous DNA segment in the leukemic cells and in follicular lymphoma cells with the t(14:18) chromosome translocation but not in other neoplastic or normal B or T cells. The probe appears to identify bcl-2, a gene locus on chromosome 18 (band q21) that is unrelated to known oncogenes and may be important in the pathogenesis of B-cell neoplasms with this translocation.

Human neuroblastomas and abnormalities of chromosomes 1 and 17.

Abstract: Structural rearrangements of chromosome 1p have been reported previously as a frequent finding in human neuroblastomas. In a review of karyotypes from 35 neuroblastomas (including 29 published cases and 6 unpublished tumors and cell lines), it was found that, in addition to the abnormalities of chromosome 1p (found in approximately 70% of cases), abnormalities involving only 2 other chromosome segments occurred with significant frequency (in 20% or more of cases) in this cancer. These abnormalities involved trisomies for the long arms of chromosomes 1 and 17. In addition, two novel cytogenetic aberrations, homogeneously staining regions and double minutes, were identified in two-thirds of the cases. It is postulated that the gene change(s) produced by the abnormalities of chromosome 1p in neuroblastoma play a primary role in the development of this cancer. The gene changes produced by the abnormalities of chromosomes 1q and 17q and by the homogeneously staining regions and double minutes are presumed to contribute to tumor progression.

A 14;18 and an 8;14 chromosome translocation in a cell line derived from an acute B-cell leukemia

Abstract: We have established a cell line, which we named 380, from a young male with acute lymphoblastic leukemia (FAB type L2). Karyologic analysis of this cell line indicates that it carries an 8;14 and a 14;18 chromosome translocation, which are characteristic of Burkitt lymphoma and of follicular lymphoma, respectively. This cell line is Epstein-Barr virus antigen-negative, reacts with monoclonal antibodies specific for B cells, and contains rearranged immunoglobulin heavy and light chain genes, but does not express human immunoglobulins. In this cell line, both mu heavy chain constant (C mu) loci are rearranged within the joining (JH) DNA segment. One of the JH segments on one of the 14q+ chromosomes is rearranged with a segment of chromosome 8, where the c-myc oncogene resides, while the other is rearranged with a segment of chromosome 18 where a putative oncogene, which we have called bcl-2, is located. The c-myc oncogene, which is translocated to one of the 14q+ chromosomes, is in its germ-line configuration more than 14 kilobases away from both the JH segment and the heavy chain enhancer that is located between the JH and mu switch region. Based on these findings, we propose a model of some aspects of B-cell oncogenesis according to which B-cell neoplasms carrying translocations involving the heavy chain loci on both human chromosomes 14 are the result of a multiple step process.

Occurrence of a transposition from the X-chromosome long arm to the Y-chromosome short arm during human evolution

Abstract: DXYS1, a site showing greater than 99% DNA sequence homology between the human X and Y chromosomes, maps to the X long arm and to the Y short arm. In great apes, sequences homologous to DXYS1 are found only on the X chromosome. These findings suggest an X–Y transposition during human evolution.

High-Resolution Chromosome Sorting and DNA Spot-Blot Analysis Assign McArdle's Syndrome to Chromosome 11

Abstract: A rapid gene-mapping system uses a high-resolution, dual-laser sorter to identify genes from separate human chromosomes prepared with a new stain combination. This system was used to sort 21 unique chromosome types onto nitrocellulose filter papers. Several labeled gene probes hybridized to the sorted chromosomal DNA types predicted by their previous chromosome assignments. The skeletal muscle glycogen phosphorylase gene was then mapped to a portion of chromosome 11 by spot blotting normal and translocated chromosomes.

Nonrandom chromosomal changes in transitional cell carcinoma of the bladder.

Abstract: Nine cases of transitional cell carcinoma (eight from the urinary bladder and one from the ureter; six noninvasive and three invasive) were subjected to detailed cytogenetic analysis with a G-banding method. The synchronization of primary cultures with methotrexate for high-resolution banding was performed in five cases. In the remaining four cases, the chromosomes were obtained from short-term cultures after prolonged (16 hr) exposure to Colcemid. Two cases were near-tetraploid, one was hypotriploid, and six were near-diploid (three hyperdiploid and three hypodiploid). All but one case showed various structural abnormalities in the karyotype. The chromosomal changes ranged from the presence of only two abnormal chromosomes (markers) to complex karyotypes with as many as 15 markers. In most tumors, the origin of the marker chromosomes could be readily deciphered. The nonrandom chromosomal aberrations included: ( a ) an isochrosome of the short arm of chromosome 5 (three cases); ( b ) monosomy of chromosome 9 found in four cases (this was the sole abnormality in one case); ( c ) involvement of chromosome 8 as an isochromosome of the long arm (two cases) or loss of the short arm due to deletion (one case) or translocation (one case); and ( d ) interstitial deletion of chromosome 13 (three cases). Our results indicate that the formation of i(5p) and monosomy 9 may be the primary karyotypic changes in two subgroups of transitional cell carcinoma. Involvement of chromosomes 8 and 13, on the other hand, seems to be a result of secondary karyotypic evolution. Two invasive tumors showed the presence of secondary clones, with additional structural chromosome aberrations superimposed on those already existing in the main cell population. In both cases, the additional aberrations involved the short arm of chromosome 11, resulting in loss of genetic material from the short arm. The short arm of chromosome 11, is the putative site of an oncogene which has been isolated from human bladder carcinoma cell lines. Deletion of the 11p was also seen in one case of noninvasive transitional cell carcinoma localized in the ureter; the material from 11p was probably translocated to chromosome 13. These findings suggest that the loss of genetic material from the short arm of chromosome 11 is a secondary event in the karyotypic evolution of transitional cell carcinoma, probably related to the invasive behavior of the tumor.

Human XX males with Y single-copy DNA fragments

Abstract: In humans, XX maleness is the best known example of a sex reversal syndrome occurring with an incidence of one XX male among approximately 20,000 to 30,000 newborn boys. The karyotypes of the majority of these individuals are apparently normal, with respect to the numbers and structure of the chromosomes, but is in contradiction with the phenotypic sex which they display. XX maleness may be either a non Y-related mechanism triggered by a mutation on another chromosome or could be the result of the expression of some cytogenetically undetectable Y chromosome material present in the genome of such individuals. Recently, a number of human Y-specific single copy probes have been isolated. In this study, using several of these Y-specific probes we definitively demonstrate the presence of Y-chromosomal material in the genome of some 46,XX human males. These XX males carry only a fraction of the human Y chromosome. In the three positive cases reported here, presence of inclusive overlapping chromosomal fragments has been detected, implying a genetic heterogeneity of these patients.

Aberrant expression of an amplified c-myb oncogene in two cell lines from a colon carcinoma

Abstract: Two cell lines (COLO 201 and COLO 205) derived independently from a single adenocarcinoma of the human colon each harbored an approximately 10-fold amplification of the cellular oncogene c-myb and a proportional abundance of the 4-kilobase mRNA derived from c-myb. By contrast, expression of c-myb could not be detected in cells from a variety of other solid tumors, including other colon carcinomas. Analysis of the amplified DNA with restriction endonucleases failed to reveal any topographical abnormalities within c-myb. Neither COLO 201 nor COLO 205 carry the double minute chromosomes and homogeneously staining regions of chromosomes that frequently serve as karyotypic signatures of amplified DNA. Instead, amplified c-myb is carried on what appear to be disomic or trisomic copies of the same anomalous marker chromosome that is characteristic of both COLO 201 and COLO 205. The karyological origin of this abnormal chromosome is not presently apparent. Our findings show c-myb expression by cells outside of the hemopoietic lineage, raise the possibility that amplification and/or ectopic expression of c-myb may have contributed to the genesis of the tumor from which the cells of COLO 201 and COLO 205 arose, and suggest that amplification of cellular oncogenes may be a more common factor in tumorigenesis than might have been suspected from available karyological data.

Common region on chromosome 14 in T-cell leukemia and lymphoma

Abstract: Chromosome 14 breakpoints in malignant human lymphocytes cluster on the long (q) arm near bands q11 and q32. An inversion of chromosome 14 due to breaks in q11.2 and q32.3 has now been found in a newly established childhood T-cell lymphoma cell line and confirmed in T-cell chronic lymphocytic leukemia. A translocation was also found between chromosomes 10 and 14 with a breakpoint at 14q11.2 in another T-cell lymphoma cell line. It is proposed that a proximal region on chromosome 14 in or near sub-band q11.2 is related to T-cell function. Rearrangements in this region may affect the growth of T lymphocytes and be involved in the development of T-cell malignancies.

Translocations and other karyotypic structural changes in wheat x rye hybrids regenerated from tissue culture.

Abstract: The spontaneous occurrence of chromosome breaks, deletions, and translocations in plant tissue cultures is well documented. This study investigated the usefulness of tissue culture as a method of introgressing alien genes into wheat. Wheat X rye hybrids were regenerated from embryo scutellar calli maintained in culture for 222 days. The regenerated seedlings then were treated with colchicine to produce amphidiploids (AABBDDRR). The karyotypes of ten amphidiploids were analyzed by C-banding to determine chromosome structural changes that occurred during tissue culture. Three wheat/rye and one wheat/wheat chromosome translocations, seven deletions, and five amplifications of heterochromatin bands of rye chromosomes were identified. One amphidiploid contained a reciprocal translocation between wheat chromosome 4D and rye chromosome 1R. Non-reciprocal translocations between 2B and 3R, and between an unidentified wheat chromosome and 2R, were found independently in two amphidiploids. An additional plant had a translocation between wheat chromosomes 6B and 5A. All deletions involving rye chromosomes were noted in all 10 amphidiploids. Twelve of the 13 breakpoints in chromosomes involved in translocations and deletions occurred in heterochromatin. Amplification of heterochromatin bands on 2RL and 7RL chromosome arms also was observed in five plants. These results indicate a high degree of chromosome structural change induced by tissue culture. Therefore, tissue culture may be a useful tool in alien gene introgression and manipulation of heterochromatin in triticale improvement.

Somatic karyotype, heterochromatin distribution, and nature of chromosome differentiation in common wheat, Triticum aestivum L. em Thell

Abstract: Heterochromatin distribution and structural differentiation of somatic chromosomes of five common wheat cultivars — Chinese Spring, Wichita, Cheyenne, Timstein, and Hope — were studied by an acetocarmine/N-banding technique. Detailed morphological observations on acetocarmine stained somatic chromosomes of Chinese Spring were made on all A genome chromosomes (except 1A), all B genome chromosomes, and chromosomes 1D, 2D, and 7D. N-banding patterns of chromosomes 2A, 3A, 5A, 6A, 1D, 2D, and 7D were described for the first time. Substitution lines of 21 individual chromosomes each of Cheyenne, Timstein, and Hope in Chinese Spring were analyzed by N-banding. A high frequency of N-band polymorphism was observed, especially for most of the B genome chromosomes. Chromosomes 3A, 5A, 2D, and 7D showed a constant banding pattern. Three cases of doubtful substitutions, Hope 2A, 2B, and Timstein 7A, and several cases of incomplete and chromosomally modified substitutions were observed. The reduced level of chromosome pairing that is often observed in intercultivar hybrids of wheat may be due to heterochromatic differentiation, genic and structural heterozygosity, or hybrid dysgenesis.

Chromosomal and nuclear distribution of the HindIII 1.9-kb human DNA repeat segment

Abstract: A human interspersed repetitive DNA cloned in pBR322, the HindIII 1.9-kb (kilobase pair) sequence, was labeled with biotinylated dUTP and hybridized to acid-fixed chromosomes and paraformaldehyde-fixed whole cells in situ. Using our most sensitive detection techniques this probe highlighted on the order of 200 discrete loci, in punctate or banded arrays, that resembled a Giemsa-dark band pattern on chromosome arms. Interphase cells also displayed many discrete punctate spots of hybridization along chromosome fibers. The ubiquitous Alu sequence repeat also appeared to be concentrated in specific regions of the chromosome and predominantly highlighted Giemsa-light bands. Centromeric or ribosomal spacer DNA repeats used as controls in all studies gave the expected hybridization profiles and showed no non-specific labeling of chromosome arms. Cohesive groups of centromeric DNA arrays and rDNA clusters were observed in interphase nuclei. Refinements in methods for detecting biotin-labeled probes in situ were developed during these studies and calculations indicated that about 20 kb or more of the 1.9-kb repeat were present at each hybridization site. The chromosomal distribution of the 1.9-kb repeat suggests that this sequence may reflect, or participate in defining, ordered structureal domains along the chromosome.

Chromosome Changes in Soft Tissue Sarcomas

Abstract: An analysis of chromosome aberrations in human tumors was performed in 29 cases of soft tissue sarcoma. The tumor tissues were disaggregated with collagenase and the cells cultured for 2-3 days. Analyzable metaphases were obtained in 15 cases, 4 of which showed only normal karyotypes. The remaining 11 tumors showed various numerical and structural abnormalities in their karyotypes: 8 tumors were near-diploid and the remaining 3 were near-triploid. G- and Q-banding analyses revealed clonal abnormalities in the 11 cases with the presence of marker chromosomes; 15 different chromosomes were involved in chromosome rearrangements, chromosomes 1 and 2 being the most frequently affected. Because of the heterogeneity of the tumor group investigated (neurogenic sarcoma, 2 liposarcomas, neurofibrosarcoma, synovial cell sarcoma, fibrosarcoma, mesothelioma, leiomyosarcoma, rhabdomyosarcoma, Ewing's sarcoma, and hemangiopericytoma), it was impossible to reach any conclusion on the specificity of the cytogenetic abnormalities for a particular tumor type.

An early stage of ZW/ZZ sex chromosome differentiation in Poecilia sphenops var. melanistica (Poeciliidae, Cyprinodontiformes)

Abstract: The mitotic and meiotic chromosomes of the American cyprinodont fish Poecilia sphenops var. melanistica were analysed. All 46 chromosomes are telocentric. By specific staining of the constitutive heterochromatin with C-banding and various AT-specific fluorochromes, the homomorphic chromosome pair 1 could be identified as sex chromosomes of the ZW/ZZ type. All female animals exhibit a W chromosome with a large region of telomeric heterochromatin that is not present in the Z chromosome. These sex chromosomes cannot be distinguished by conventional staining; they represent the first demonstration of sex chromosomes in fishes in an early stage of morphological differentiation. The W heterochromatin and the telomeric heterochromatin in the two autosomes 18 show a very bright fluorescence when stained with AT-specific fluorochromes. This allows the direct identification of the chromosomal sex by examining the interphase nuclei: females exhibit three, males only two brightly fluorescent heterochromatic chromocenters in their nuclei. The significance of these ZW/ ZZ sex chromosomes and their specific DNA sequences, the dose compensation of the Z-linked genes, and the experimental possibilities using sex-reversed “ZW males” are discussed.

An improved method for G-banding chromosomes after in situ hybridization.

Abstract: We report a method for producing high-resolution G-bands on chromosomes of normal and neoplastic human cells after hybridization of 3H-labeled probes to the chromosomes and after autoradiography

Chromosomes of kinetoplastida.

Abstract: We have compared chromosome-sized DNA molecules (molecular karyotypes) of five genera (nine species) of kinetoplastida after cell lysis and deproteinization of DNA in agarose blocks and size fractionation of the intact DNA molecules by pulsed field gradient (PFG) gel electrophoresis. With the possible exception of Trypanosoma vivax and Crithidia fasciculata, all species have at least 20 chromosomes. There are large differences between species in molecular karyotype and in the chromosomal distribution of the genes for alpha- and beta-tubulin, rRNA and the common mini-exon sequence of kinetoplastid mRNAs. In all cases, the rRNA genes are in DNA that is larger than 500 kb. Whereas T. brucei has approximately 100 mini-chromosomes of 50-150 kb, only few are found in T. equiperdum; T. vivax has no DNA smaller than 2000 kb. As all three species exhibit antigenic variation, small chromosomes with telomeric variant surface glycoprotein genes cannot be vital to the mechanism of antigenic variation. The apparent plasticity of kinetoplastid genome composition makes PFG gel electrophoresis a potentially useful tool for taxonomic studies.

Relationships within the melanogaster species subgroup of the genus Drosophila (Sophophora). IV: The chromosomes of two new species

Abstract: The polytene chromosomes of two new species of Drosophila, D. sechellia and D. orena, both members of the melanogaster species subgroup, are described. The chromosomes of D. sechellia, a species endemic to certain islands in the Seychelles, are homosequential with those of D. simulans and D. mauritiana. The chromosomes of D. orena, a species from the mountains of west Africa, are very similar to those of D. erecta. We discuss the interrelationships of the eight known species of the melanogaster species subgroup, based upon an analysis of their chromosome banding patterns.

A human c-erbA oncogene homologue is closely proximal to the chromosome 17 breakpoint in acute promyelocytic leukemia

Abstract: A human cDNA library was screened for sequences homologous to the erbA gene of avian erythroblastosis virus (AEV). One such clone, cHerbA-1, was used to map the chromosomal location of highly homologous human sequences that were found to be present on chromosome 17 as judged by Southern blot screening of a panel of mouse-human hybrid cell lines segregating human chromosomes. cHerbA-1 was hybridized in situ to metaphase chromosomes from a normal male subject and from a female patient with an acute promyelocytic leukemia (APL) having the typical t(15;17) translocation. The results localized the cellular c-erbA sequences on chromosome 17 to the q21-q24 region of normal chromosomes and indicated that the c-erbA sequences remained on the 17q- chromosome in the APL cells, suggesting that they could be assigned to the 17(q21-q22) region. For additional data, we hybridized human neoplastic cells derived from a poorly differentiated acute leukemia carrying a t(17;21) translocation with thymidine kinase (TK)-deficient LMTK- mouse cells. A resulting hybrid, containing only the 21q+ chromosome, did not have human c-erbA sequences. Since the breakpoint on 17q in this translocation was similar to that in the APL t(15;17) translocation, this supported the assignment of c-erbA to the q21-q22 region of chromosome 17. The apparent close proximity of the c-erbA sequences to the chromosomal breakpoints in these two leukemias suggests a possible role for this oncogene homologue in the development of these neoplasms.

Compound kinetochores of the Indian muntjac. Evolution by linear fusion of unit kinetochores.

Abstract: The chromosomes of the Indian muntjac (Muntiacus muntjak vaginalis) are unique among mammals due to their low diploid number (2N=6♀, 7♂) and large size. It has been proposed that the karyotype of this small Asiatic deer evolved from a related deer the Chinese muntjac (Muntiacus reevesi) with a diploid chromosome number of 2n= 46 consisting of small telocentric chromosomes. In this study we utilized a kinetochore-specific antiserum derived from human patients with the autoimmune disease scleroderma CREST as an immunofluorescent probe to examine kinetochores of the two muntjac species. Since CREST antiserum binds to kinetochores of mitotic chromosomes as well as prekinetochores in interphase nuclei, it was possible to identify and compare kinetochore morphology throughout the cell cycle. Our observations indicated that the kinetochores of the Indian muntjac are composed of a linear beadlike array of smaller subunits that become revealed during interphase. The kinetochores of the Chinese muntjac consisted of minute fluorescent dots located at the tips of the 46 telocentric chromosomes. During interphase, however, the kinetochores of the Chinese muntjac clustered into small aggregates reminiscent of the beadlike arrays seen in the Indian muntjac. Morphometric measurements of fluorescence indicated an equivalent amount of stained material in the two species. Our observations indicate that the kinetochores of the Indian muntjac are compound structures composed of linear arrays of smaller units the size of the individual kinetochores seen on metaphase chromosomes of the Chinese muntjac. Our study supports the notion that the kinetochores of the Indian muntjac evolved by linear fusion of unit kinetochores of the Chinese muntjac. Moreover, it is concluded that the evolution of compound kinetochores may have been facilitated by the nonrandom aggregation of interphase kinetochores in the nuclei of the ancestral species.

A photographic representation of the variability in the G-banded structure of the chromosomes in the mouse karyotype. A guide to the identification of the individual chromosomes.

Abstract: Analysis of the mouse chromosomes is becoming increasingly important in many fields of genetic research. It is generally considered that the mouse chromosomes are more difficult to analyse than, for example, human chromosomes which has often led to their misidentification. This article presents a guide to the correct identification of trypsin-Giemsa banded chromosomes from the mouse. The variability in the G-banded structure of each chromosome is presented pictorially together with some suggestions for their unequivocal identification. Since many of the mouse chromosomes have similar banding patterns, those chromosomes which are more frequently misidentified have been compared and contrasted. Finally a summary of the main features for the identification of each chromosome is presented.

Chromosome 15 anomalies and the Prader-Willi syndrome: cytogenetic analysis.

Abstract: The behaviour of chromosome 15 is very different from that of the other acrocentric chromosomes. The cytogenetic characteristics of rearrangements associated with Prader-Willi syndrome (PWS) are analyzed as similar rearrangements irrespective of the associated phenotype (reciprocal translocations of chromosome 15, small bisatellited additional chromosomes, Robertsonian translocations, interstitial deletions, pericentric inversions). This study suggests that: (1) The proximal (15q) region and PWS seem to be indissociable; (2) chromosome 15 has an indisputable cytogenetic originality which could be related to its histochemical properties. Chromosome 15 constitutive heterochromatin usually contains much 5-methylcytosine-rich DNA and a large amount of each of the four satellite DNAs. Furthermore the existence in the proximal (15q) region of one or several palindromic sequences could be postulated to explain the great lability of this region of chromosome 15.

The chromosome 14 breakpoint in neoplastic B cells with the t(11;14) translocation involves the immunoglobulin heavy chain locus

Abstract: We hybridized neoplastic cells from a patient with chromic lymphocytic leukemia of the B-cell type, which carried a reciprocal chromosomal translocation between chromosomes 11 (q13) and 14 (q32) with mouse plasmacytoma cells. The hybrid cells were studied for the presence, rearrangement, and expression of the human immunoglobulin mu chain locus. The results indicate that the expressed mu chain gene is located on the normal chromosome 14, whereas the 14q+ translocation chromosome carries the excluded immunoglobulin constant (C) region mu chain allele (C mu) but does not contain variable (V) region heavy chain genes (VH). Since we found that the heavy chain joining region DNA (JH) of the excluded mu chain gene is on the 14q+ chromosome, we can conclude that the chromosomal break observed in the leukemic cells occurred in a chromosomal region within or 5' of the JH region. With these results, it is logical to postulate that a gene, for which we suggest the name bcl-1, is located on band q13 of chromosome 11 and is activated by its translocation into close proximity with the rearranged heavy chain locus on chromosome 14q+, contributing to the neoplastic transformation of the B cells with the t(11;14) chromosomal translocation.