Showing papers on "Karyotype published in 1997"
Journal Article•
TL;DR: The relative distribution of losses indicated that different bands/regions are affected in different tumor types and that, often, several distinct candidate tumor suppressor gene loci can be discerned within the same chromosome arm, e.g., 1p12-13, 1 p22, 1p34, and 1p36 on the short arm of chromosome 1 and 7q22, 7q32, and 7Q32 on the long arm of chromosomes 7.
Abstract: To assess the distribution of gains and losses of genetic material in malignant solid neoplasms, 11 tumor types for which at least 100 short-term cultured cases with clonal chromosome aberrations had been reported in the literature were selected. The study was based on cytogenetic information from 508 breast carcinomas, 447 malignant neuroglial tumors, 435 kidney carcinomas, 333 colon carcinomas, 304 ovarian carcinomas, 303 lung carcinomas, 209 testicular germ cell tumors, 206 head and neck carcinomas, 172 malignant melanomas, 142 Wilms' tumors, and 126 neuroblastomas. In each case, the net imbalances were calculated for each chromosome band. The profiles of gains and losses revealed that all tumor types display unique combinations of imbalances. However, there is also considerable overlap among the profiles of the different diagnostic entities, indicating that similar molecular mechanisms may be operative in the development of many types of neoplasia. Deletions were more common than gains in all tumor types, with chromosomes X, Y, 4, 10, 13-15, 18, and 22 and chromosome segments 1p22-pter, 3p13-pter, 6q14-qter, 8p, 9p, and 11p being particularly often deleted in the majority of tumors. To better delineate critical lost segments, deletion profiles based only on structural rearrangements were made for chromosomes 1, 3-12, and 17, which all had on average at least four registered deletions per band. The relative distribution of losses indicated that different bands/regions are affected in different tumor types and that, often, several distinct candidate tumor suppressor gene loci can be discerned within the same chromosome arm, e.g., 1p12-13, 1p22, 1p34, and 1p36 on the short arm of chromosome 1 and 7q22, 7q32, and 7q36 on the long arm of chromosome 7. The only chromosomes or chromosome segments more often gained than deleted were chromosomes 7 and 20 and the long arms of chromosomes 1 and 12, suggesting the presence there of dominantly acting growth-regulatory genes. The data presented in this study should be valuable as a guide for molecular genetic studies on allelic imbalances and for the interpretation of results from studies using comparative genomic hybridization.
456 citations
TL;DR: 11q deletions identify a new clinical subset of B-CLL characterized by extensive lymph node involvement and strongly depended on the age: in patients less than 55 years old, the median survival time was significantly shorter in the deletion group (64 months v 209 months; P < .001), whereas in patients > or =55 years old there was no significant difference (94 months v 111 months).
441 citations
TL;DR: Spectral karyotyping (SKY) as discussed by the authors is a hybrid approach based on the hybridization of 24 fluorescently labelled chromosome painting probes that allows simultaneous and differential color display of all human chromosomes.
Abstract: Cytogenetic analysis provides critical information of diagnostic and prognostic importance for haematological malignancies1,2. In fact, the identification of recurring chromosomal breakpoints in leukaemias and lymphomas has expedited the cloning of genes whose translocation-induced deregulation causes malignant transformation3,4. The pillar of karyotype analysis rests on chromosome banding techniques that have the distinct advantage that the entire genome can be analysed in a single experiment. However, poorly spread or contracted metaphase chromosomes and highly rearranged karyotypes with numerous marker chromosomes, common in tumour cell preparations, are often difficult to interpret unambiguously and subtle chromosomal aberrations, in particular the exchange of telomeric chromatin or small insertions remain elusive. Fluorescence in situ hybridization (FISH) overcomes some of these limitations, but is mainly utilized to confirm the presence of previously characterized or suspected aberrations5. We have developed a novel approach, termed spectral karyotyping or SKY6,7 based on the hybridization of 24 fluorescently labelled chromosome painting probes that allows the simultaneous and differential colour display of all human chromosomes. We have used SKY to complement conventional banding techniques in haematological malignancies by analysing 15 cases with unidentified chromosome aberrations. In all instances SKY provided additional cytogenetic information, including the identification of marker chromosomes, the detection of subtle chromosomal translocations and the clarification of complex chromosomal rearrangements. Thus, SKY in combination with standard chromosome banding allows the characterization of chromosomal aberrations in leukaemia with unprecedented accuracy.
356 citations
Journal Article•
TL;DR: The study strengthens the notion that different tumor subgroups of the respiratory tract are characterized by distinct patterns of chromosomal alterations.
Abstract: Comparative genomic hybridization was used to screen 25 adenocarcinomas and 25 squamous cell carcinomas of the lung for chromosomal imbalances. DNA copy number decreases common to both entities were observed on chromosomes 1p, 3p, 4q, 5q, 6q, 8p, 9p, 13q, 18q, and 21q. Similarly, DNA gains were observed for chromosomes 5p, 8q, 11q13, 16p, 17q, and 19q. Adenocarcinomas showed more frequently DNA overrepresentations of chromosome 1q and DNA losses on chromosomes 3q, 9q, 10p, and 19, whereas squamous cell carcinomas were characterized by increased overrepresentations of chromosome 3q and 12p as well as deletions of 2q. For the first time, we used a histogram representation and statistical analysis to evaluate the differences between both tumor groups. In particular, the overrepresentation of the chromosomal band 1q23 and the deletion at 9q22 were significantly associated with adenoid differentiation, whereas the DNA loss of chromosomal band 2q36-37 and the overrepresentations at 3q21-22 and 3q24-qter were statistically significant markers for the squamous cell type. The study strengthens the notion that different tumor subgroups of the respiratory tract are characterized by distinct patterns of chromosomal alterations.
276 citations
TL;DR: The presence of deletions was evaluated relative to patient's sperm concentration, testis volume, and hormonal parameters, and other clinical parameters did not identify men with Y chromosome deletions prior to polymerase chain reaction (PCR)-based testing for the presence of sequence-tagged-sites.
Abstract: some (Yq). They proposed the presence of an azoospermic525 East 68th Street, New York, NY 10021, USA factor (AZF) in the distal euchromatic region of Yq. The limitedRecent investigations have suggested a high prevalence resolution afforded by karyotypic analysis was significantlyof Y chromosome submicroscopic deletions in men with improved with the advent of polymerase chain reaction (PCR)and the construction of Y chromosome maps. Chandley andseverely impaired spermatogenesis. We evaluated the fre-Cooke (1994) studied 50 azoospermic and oligozoospermicquency of Y chromosome deletions in 160 infertile menmen and found deletions in interval 6 of Yq for four menusing a series of 36 sequence-tagged-sites, emphasizing(8%). They characterized a family of genes from this deletedintervals 5 and 6 of the long arm of the Y chromosome.region with RNA-binding protein homology and testis-specificPeripheral leukocyte DNA was extracted and amplifiedexpression that were termed Y chromosome RNA recognitionwith two parallel techniques to minimize potential over-motifs [YRRM(RBM); Ma et al., 1993]. However,estimation of the frequency of deletions. The presenceYRRM(RBM) is a redundant gene, with multiple copies foundof deletions was evaluated relative to patient’s spermalong the long arm of the Y chromosome, and at least oneconcentration, testis volume, and hormonal parameters.YRRM(RBM) sequence variant (a polymorphism) has beenMen with sperm concentration
197 citations
TL;DR: The high incidence of chromosomal loss is an indication that SCLC is defined by a pattern of deletions and that the inactivation of multiple growth-inhibitory pathways contributes in particular to the aggressive phenotype of that type of tumour.
Abstract: The genetic mechanisms that define the malignant behaviour of small-cell lung cancer (SCLC) are poorly understood. We performed comparative genomic hybridization (CGH) on 22 autoptic SCLCs to screen the tumour genome for genomic imbalances. DNA loss of chromosome 3p was a basic alteration that occurred in all tumours. Additionally, deletions were observed on chromosome 10q in 94% of tumours and on chromosomes 4q, 5q, 13q and 17p in 86% of tumours. DNA loss was confirmed by loss of heterozygosity (LOH) analysis for chromosomes 3p, 5q and 10q. Simultaneous mutations of these six most abundant genetic changes were found in 12 cases. One single tumour carried at least five deletions. DNA under-representations were observed less frequently on chromosome 15q (55%) and chromosome 16q (45%). The prevalent imbalances were clearly indicated by the superposition of the 22 tumours to a CGH superkaryogram. In our view, the high incidence of chromosomal loss is an indication that SCLC is defined by a pattern of deletions and that the inactivation of multiple growth-inhibitory pathways contributes in particular to the aggressive phenotype of that type of tumour.
189 citations
TL;DR: The preliminary data support the possibility of an increased risk from paternal origin sex chromosome aneuploidies in children born after intracytoplasmic sperm injection (ICSI), and further investigations of the cytogenetic constitution of spermatozoa from severe male factor patients is warranted.
Abstract: The purpose of the study was to analyse the frequency of sex-chromosome numerical abnormalities in human spermatozoa of infertile men by using a standardized experimental protocol of double target in-situ hybridization (ISH). The experiments were performed on decondensed sperm heads from 15 infertile patients (six cases of unexplained infertility and nine cases of severe oligoasthenoteratozoospermia). Three men of proven fertility were used as controls. The probes employed recognized the centromeric regions of human X chromosome and the long arm of the Y chromosome. In a smaller number of cases, additional experiments of double ISH were performed using centromeric probes for chromosomes 1 and 17. Signal detection was based on protocols of enzymatic cytochemical reactions. A total of 24,508, 24,679 and 42,285 cells were scored in the control, unexplained infertility and severe male factor groups of patients respectively. In all the patients in the ISH efficiency result was approximately 98%. In controls, unexplained infertility and severe male factor patients, the frequency of morphologically normal sperm cells carrying an abnormal chromosome constitution (XX or YY or XY or > 2 sex chromosomes signals) was 0.86, 0.75 and 1.35% respectively. The value of this last group of patients (severe male factor) was significantly higher than in the other two groups of patients (P < 0.008). The same findings were made using the autosomic probes. Our preliminary data support the possibility of an increased risk from paternal origin sex chromosome aneuploidies in children born after intracytoplasmic sperm injection (ICSI). Further investigations of the cytogenetic constitution of spermatozoa from severe male factor patients is warranted.
152 citations
TL;DR: The results suggest that low level 20q gain is associated with overcoming cellular senescence in E7 transformed cells (P-value=2×10−7), but does not confer genome instability, while highlevel 20q13.2 amplification is associatedwith chromosome instability.
Abstract: Breast, bladder, colon, and ovarian carcinomas show frequent low level 20q gain and less frequently high level 20q13.2 amplification, but the significance of these 20q amplifications in transformation has not been defined. Using karyotypic and comparative genomic hybridization (CGH) analyses, chromosome losses and gains were analysed in six newly immortalized human uroepithelial cell (HUC) lines transformed by Human Papillomavirus 16 (HPV16) E7. Results showed clonal chromosomes with 20q11->qter gain in all six lines. CGH revealed a peak of 20q13.2 amplification in two cell lines. FISH with whole chromosome 20 paint showed expanded chromosome regions (ECRs) and double minute chromosomes (DMs) that contained chromosome 20 material in cell lines with 20q13.2 amplification. FISH with probes from the center of the 20q13.2 human breast cancer amplicon showed as many as 24 signals in cells with 20q13.2 amplification. The acquisition of genome instability in these E7-HUCs did not correlate with TP53 mutation, as all E7-HUCs contained only wildtype TP53. These results suggest that low level 20q gain is associated with overcoming cellular senescence in E7 transformed cells (P-value=2 x 10(-7)), but does not confer genome instability, while high level 20q13.2 amplification is associated with chromosome instability. Loss of 10p (P-value = 3 x 10(-5)) was also important in immortalization of E7-transformed HUCs. Thus, these results have profound implications for interpreting the significance of high versus low level 20q gains in human cancers.
141 citations
TL;DR: Prenatal cytogenetic analysis of 71 fetuses conceived by intracytoplasmic sperm injection resulted in the detection of nine chromosome aberrations including two cases of 47,XXY, four cases involving a 45,X cell line and three autosomal trisomies.
Abstract: Prenatal cytogenetic analysis of 71 fetuses conceived by intracytoplasmic sperm injection (ICSI) resulted in the detection of nine (12.7%) chromosome aberrations including two cases of 47,XXY, four cases involving a 45,X cell line and three autosomal trisomies. Molecular analysis of the parental origin of the deleted or supernumerary chromosome was performed by using polymorphic microsatellite markers. Six cases involving a sex chromosome abnormality were found to be of paternal origin while the two trisomic cases that could be analysed were of maternal origin. Two cases involved the same infertile couple who had two consecutive ICSI pregnancies terminated because of a chromosome abnormality. The replaced embryos in both cases originated from a single batch of ICSI fertilized oocytes of which part was used to initiate the first pregnancy and part was cryopreserved and used to initiate the second pregnancy.
133 citations
TL;DR: The results suggest that reciprocal chromosome painting will help reconstruct the history of genomic changes by determining the polarity of chromosomal rearrangements and establishing the ancestral karyotype for each principle branching point in mammalian evolution.
Abstract: We employed fluorescence in situ hybridization (FISH) with probes established by flow sorting metaphase chromosomes of the domestic cat ( Felis cattus , 2n = 38) to “paint” homologous
127 citations
TL;DR: The characteristic pattern of chromosomal gains and losses detected in this study confirms the distinct nature of MZBCL and may point to chromosomal regions involved in the pathogenesis of these neoplasms.
Abstract: Marginal zone B cell lymphoma (MZBCL) represents a distinct subtype of B cell non-Hodgkin's lymphoma, which has been recently recognized and defined as a disease entity. We investigated 25 cases (18 at primary diagnosis and seven during the course of disease) of MZBCL by comparative genomic hybridization (CGH) and compared these results with cytogenetic, fluorescence in situ hybridization (FISH), and Southern blot data. Twenty of the 25 cases (80%) showed gains (total 49) or losses (total 15) of genetic material. In extranodal, nodal, and splenic MZBCL, material of chromosomes 3 (52% of cases), 18 (32%), X (24%), and 1q (16%) was most frequently gained, whereas losses predominantly involved chromosomes 17 (16%) and 9 (12%). High-level amplifications involving the regions 18q21-23 and 18q21-22, respectively, were detected in two cases. Gains of chromosomes 1q and 8q and losses of chromosome 17 or 17p occurred more frequently in relapsed or progressive lymphomas. For all of the frequently affected chromosomes, CGH allowed narrowing of the relevant subregions including 3q21-23, 3q25-29 and 18q21-23. By Southern blot analysis, the BCL2, BCL6, and CMYC proto-oncogenes were found to be a part of the over-represented regions in two cases, one case, and two cases, respectively, with gains involving 18q, 3q or 8q. In 13 cases, CGH revealed chromosomal imbalances which were not detected by cytogenetic analysis but could be confirmed by FISH or Southern blot analysis in all cases investigated. On the other hand, CGH failed to detect trisomy 3, trisomy 18, and deletion 7q in three cases with a low proportion of tumor cells bearing these abnormalities, as shown by interphase FISH. The characteristic pattern of chromosomal gains and losses detected in this study confirms the distinct nature of MZBCL and may point to chromosomal regions involved in the pathogenesis of these neoplasms.
TL;DR: The history of domestic horse cytogenetics dates from 1912 when Kirillow reported the diploid chromosome number to be between 20 and 34 in male horses, and a new standard (the Paris Standard) was led in 1989, which was more compact, with relatively better band resolution than the Reading Standard.
Abstract: The history of domestic horse (Equus caballus) cytogenetics dates from 1912 when Kirillow reported the diploid chromosome number to be between 20 and 34 in male horses (see Power 1990). Later, Krallinger (1931) and Makino (1942) reported the number to be 64. Although this provided the correct chromosome number, the prevailing uncertainty was ®nally cleared in 1959 by Rothfels and co-workers who con®rmed the correct chormosome number as 2n 64 (Rothfels et al. 1959). The horse has 13 pairs of metacentric/submetacentric and 18 pairs of acrocentric autosomes. The X chromosome is the second largest submetacentric, while the Y chromosome is one of the smallest acrocentrics. During the 1970s, G-, Q-, C-, Rand NOR banding techniques were applied to horse chromosomes, and several arrangements of the chromosomes into a karyotype were presented (see Power 1990). The First International Conference for the Standardization of Banded Karyotypes of Domestic Animals held at Reading, UK, 1976, proposed a G-banded horse karyotype (the Reading Standard) with eight rows of chromosomes (Ford et al. 1980). Biarmed autosomes were arranged by decreasing length in the ®rst four rows. Acrocentrics were similarly arranged in the next three rows. The last row had only the sex chromosomes. This standard karyotype was used for several years. The lack of complete consensus among horse cytogeneticists led to a new standard (the Paris Standard) de®ned in 1989 (Richer et al. 1990). The chromosomes were arranged into two groups ± nonacrocentrics and acrocentrics. Within each group the chromosomes were ordered by length. The sex chromosomes were placed in the middle of the karyotype, along with the smallest biarmed chromosomes. C-, Rand NOR banded karyotypes were also presented. The Paris standard karyotype was more compact, with relatively better band resolution than the Reading Standard. Despite acceptance of the Paris Standard, the quality of the published banded images was a matter of concern. Furthermore, idiograms, band numbers and landmark descriptions were not provided, limiting the use of the standard to chromosome identi®cation only. The need for schematic drawings and band designations became particularly obvious in 1988 with the ®rst reports of physical gene mapping in horses (MHC: Ansari et al. 1988, MaEkinen et al. 1989; CRC: Harbitz et al. 1990; GPI: Chowdhary et al. 1992; PGD: Gu et al. 1992). Even though G-band idiograms and band descriptions (Maciulus et al. 1984) were available before these mapping efforts, dif®culties were encountered in the precise de®nition of the band locations primarily because of the lack of consensus on landmarks and band numbers. Development of the physical and genetic Chromosome Research 1997, 5, 433±443
TL;DR: In patients with typical CLL immunophenotype, chromosome abnormalities are somewhat less frequent at the time of diagnosis than hitherto believed, but chromosome 17 abnormalities suggest a poor prognosis.
TL;DR: Advances in molecular cytogenetics can be used to test the hypothesis that chromosome rearrangement breakpoints in human pathology and in evolution are correlated, and to identify breakpoints of rearranged chromosomes.
TL;DR: The present experiments demonstrate various applications in which the present multi-color bar code can significantly add to the spectrum of cytogenetic techniques.
Abstract: A colored banding pattern for human chromosomes is described that distinguishes each chromosome in a single fluorescence in situ hybridization with a set of subregional DNA probes. Alu/polymerase chain reaction products of various human/rodent somatic cell hybrids (fragment hybrids) were pooled into two probe sets that were labeled differentially and detected by red and green fluorescence. Chromosome regions hybridized by DNA present in both pools appeared yellow. The result was a multi-color set of 110 distinct signals per haploid chromosome set for the human karyotype. Each individual chromosome showed a unique sequence of signals, a result termed the “chromosome bar code”. The reproducibility of the hybridization pattern in various labeling and hybridization experiments was analyzed by computer densitometry. We have applied the chromosome bar code both in diagnostic cytogenetics and in genome studies. The approach allows the rapid identification of chromosomes and chromosome rearrangements. Although not yet showing the resolution of classical banding patterns, the present experiments demonstrate various applications in which the present multi-color bar code can significantly add to the spectrum of cytogenetic techniques.
TL;DR: The findings suggest that patients who need microinsemination should undergo chromosome analysis and should counsel patients about obtaining adequate information on each chromosome abnormality.
Abstract: The aim of this study was to investigate the influence of a chromosome abnormality on male infertility. The subjects consisted of 1,007 males with the chief complaint of infertility. Karyotyping was conducted mainly by G banding. Major chromosome abnormalities were observed in 62 patients (6.2%) in total and consisted of sex chromosome abnormalities were observed in 62 patients (6.2%) in total and consisted of sex chromosome abnormalities in 38 patients (3.8%) and autosomal chromosome abnormalities in 24 (2.4%). Among the patients with sex chromosome abnormalities, 28 cases were 47, XXY, 3 were 47,XYY, and 7 cases had a Y chromosome abnormality. Autosomal chromosome abnormalities comprised 10 cases of reciprocal translocation, 8 cases of Robertsonian translocation, 5 cases of inversion, and 1 case of ring chromosome. In patients with a sperm density or = 30.1 mIU/ml, a luteinizing hormone value > or = 8.9 mIU/ml, a testosterone value < or = 2.69 ng/ml, or an average testis volume < or = 8 ml, the incidence of major chromosome abnormalities was significantly higher. These findings suggest that patients who need microinsemination should undergo chromosome analysis. We should counsel patients about obtaining adequate information on each chromosome abnormality.
TL;DR: Improved techniques for fluorescence in situ hybridisation and the amplification and labelling of sorted chromosomes using degenerate oligonucleotide-primed PCR have led to the widespread use of chromosome painting both for the resolution of complex chromosome aberrations and for the study of karyotype evolution by cross-species reciprocal chromosome painting.
Abstract: Chromosome sorting from fluid suspensions of metaphase chromosomes using a fluorescence-activated cell sorter has been used for a number of years to produce chromosome-specific genomic libraries and other reagents for chromosome mapping. Improved techniques for fluorescence in situ hybridisation and the amplification and labelling of sorted chromosomes using degenerate oligonucleotide-primed PCR have led to the widespread use of chromosome painting both for the resolution of complex chromosome aberrations and for the study of karyotype evolution by cross-species reciprocal chromosome painting. The chromosomes of a large number of different species have been sorted and used to make chromosome-specific paints and already new data challenging results of earlier phylogenetic studies have been obtained. Sorted chromosomes provide the resource for multicolour chromosome analysis of all chromosomes simultaneously. Such reagents are now available for all human and mouse chromosomes and are proving particularly useful in the analysis of cancer chromosomes.
TL;DR: Both the reciprocal painting patterns and localisation of the C5 probe demonstrate that M. reevesi chromosomes 1–5 and 11 could have evolved from 18 different ancestral chromosomes through 12 tandem fusions, thus providing direct molecular cytogenetic support for the tandem fusion hypothesis of karyotype evolution in M.Reesi.
Abstract: The aim of this study was to test the validity of the hypothesis that the 2n=46 karyotype of the Chinese muntjac (Muntiacus reevesi) could have evolved through 12 tandem fusions from a 2n=70 hypothetical ancestral karyotype, which is still retained in Chinese water deer (Hydropotes inermis) and brown-brocket deer (Mazama gouazoubira). Combining fluorescence-activated chromosomal sorting and degenerate oligonucleotide-primed polymerase chain reaction, we generated chromosome-specific DNA paint probes for 13 M. gouazoubira chromosomes and most of the M. reevesi chromosomes with the exception of 18, 19 and X. These paint probes were used for fluorescence in situ hybridisation to chromosomal preparations of M. reevesi, H. inermis and M. gouazoubira. Chromosome-specific paint probes from M. reevesi chromosomes 1-5 and 11 each delineated more than one homologous pair (18 pairs in total) on the metaphases of H. inermis and M. gouazoubira. All the other probes from M. reevesi and probes from M. gouazoubira each hybridised to one pair of homologous chromosomes or regions. The C5 probe, derived from centromeric satellite sequences of M. reevesi, hybridised to the centromeric regions of all chromosomes of these three species. Most interestingly, several non-random interstitial signals, which are apparently localised to the putative fusion points, were found on chromosomes 1-5 and 11 of M. reevesi. Both the reciprocal painting patterns and localisation of the C5 probe demonstrate that M. reevesi chromosomes 1-5 and 11 could have evolved from 18 different ancestral chromosomes through 12 tandem fusions, thus providing direct molecular cytogenetic support for the tandem fusion hypothesis of karyotype evolution in M. reevesi.
TL;DR: It is concluded that there is a characteristic patUPD14 syndrome most likely due to imprinting effects and couples with Robertsonian translocations involving chromosome 14 should be counseled as to the possibility of UPD14 and the option of prenatal diagnosis when indicated.
Abstract: Uniparental disomy (UPD) for several chromosomes has been associated with disease phenotypes. Maternal UPD for chromosome 14 has been described and has a characteristic abnormal phenotype. Paternal UPD14 is rare and only three previous cases have been reported. We describe a new case of paternal UPD for chromosome 14 in an infant with a 45,XX,der(13q;14q) karyotype, which was confirmed by molecular analysis. The proposita had findings similar to those of the previous cases of patUPD14 and we conclude that there is a characteristic patUPD14 syndrome most likely due to imprinting effects. Couples with Robertsonian translocations involving chromosome 14 should be counseled as to the possibility of UPD14 and the option of prenatal diagnosis when indicated.
TL;DR: It is demonstrated that the synteny of chromosomes 1, 2, 3, 4 and 5 of the Chinese muntjac has been disrupted by chromosome rearrangements other than fusions, indicating that the present karyotype of the Indian muntJac cannot be reconstructed from the hypothetical Chinese mundjac-like 2n=46 ancestral karyotypes exclusively by chromosome fusions.
Abstract: We have tested the tandem fusion hypothesis of the origin of the Indian muntjac karyotype (2n=6/7) by using reciprocal chromosome painting between the Indian muntjac, Chinese muntjac (n=46) and brown brocket deer (2n=70+3B)with chromosome-specific paint probes derived from flow-sorted chromosomes of these three deer species. Our results have shown that the euchromatic blocks of all chromosome arms of the brown brocket deer have been conserved apparently unchanged in number and content in the Indian muntjac. While confirming the conservation in toto of most of Chinese muntjac euchromatin in the karyotype of the Indian muntjac, we demonstrate that the synteny of chromosomes 1, 2, 3, 4 and 5 of the Chinese muntjac has been disrupted by chromosome rearrangements other than fusions. This indicates that the present karyotype of the Indian muntjac cannot be reconstructed from the hypothetical Chinese muntjac-like 2n=46 ancestral karyotype exclusively by chromosome fusions. Furthermore, we have shown that the breakpoints of these rearrangements appear to have occurred near to the fusion points formed during the origin of the 2n=46 karyotype of the Chinese muntjac from a 2n=70 karyotype, which is believed to be ancestral for the family Cervidae. Moreover, we substantiate that on the Indian muntjac chromosomes, the C5 probe, which is derived from the centromeric satellite sequences of the Chinese muntjac, maps to the putative fusion points determined by comparative chromosome painting and presumably represents the remnants of ancestral centromeric sequences.
TL;DR: The results contribute additional evidence that 47,XXY cells are able to complete meiosis and produce mature sperm nuclei.
Abstract: Meiotic segregation of the sex chromosomes was analysed in sperm nuclei from a man with Klinefelter's karyotype by three-colour FISH. The X- and Y-specific DNA probes were co-hybridized with a probe specific for chromosome 1, thus allowing diploid and hyperhaploid spermatozoa to be distinguished. A total of 2206 sperm nuclei was examined; 958 cells contained an X chromosome, 1077 a Y chromosome. The ratio of X:Y bearing sperm differed significantly from the expected 1:1 ratio (chi2 = 6.96; 0.001 < P < 0.01). Sex-chromosomal hyperhaploidy was detected in 2.67% of the cells (1.22% XX, 1.36% XY, 0.09% YY) and a diploid constitution in 0.23%. Although the frequency of 24,YY sperm was similar to that detected in fertile males, the frequencies of 24,XX, 24,XY and diploid cells were significantly increased. A sex-chromosomal signal was missing in 4.26% of the spermatozoa. This percentage appeared to be too high to be attributed merely to nullisomy for the sex chromosomes and was considered, at least partially, to be the result of superposition of sex-chromosomal hybridization signals by autosomal signals in a number of sperm nuclei. The results contribute additional evidence that 47,XXY cells are able to complete meiosis and produce mature sperm nuclei.
TL;DR: The results demonstrate that the reshuffling of the muntjac karyotype is mostly due to fusions of huge blocks of entire chromosomes, which is in accordance with previous chromosome painting analyses between various Muntjac species and contrasts the findings for some other mammals that show exceptional chromosome reshufflers.
TL;DR: FISH is clearly a powerful technique that has many applications in reproductive medicine, but it must also be realized that it does have limitations and the technology itself is still evolving and has yet to be fully validated on spermatozoa.
Abstract: The development and application of fluorescence in-situ hybridization (FISH) has opened the way for comprehensive studies on numerical chromosome abnormalities in human spermatozoa. FISH can be rapidly applied to large numbers of spermatozoa and thus overcomes the major limitation of karyotyping spermatozoa after penetration of zona-free hamster oocytes. The simultaneous hybridization of two or more chromosome-specific probes to spermatozoa and subsequent detection of the bound probes using different fluorescent detection systems enables two or more chromosomes to be localized simultaneously in the same spermatozoon and provides a technique for undertaking reasonable estimates of aneuploidy. The most commonly used probes are those which bind to the centromeric region of specific chromosomes. Most studies to date have concentrated on estimating aneuploidy in spermatozoa from normospermic men, although reports are beginning to appear on aneuploidy in spermatozoa from subfertile and infertile men. Multi-probe FISH studies have generally reported disomy (hyperhaploidy) estimates of 0.05-0.2% per chromosome. There is preliminary evidence that some chromosomes such as X, Y and 21 are predisposed towards higher rates of non-disjunction during spermatogenesis. There are also suggestions of inter-donor variability in aneuploidy frequencies for specific chromosomes, although this requires confirmation in larger studies. While FISH is clearly a powerful technique that has many applications in reproductive medicine, it must also be realized that it does have limitations and the technology itself is still evolving and has yet to be fully validated on spermatozoa.
Journal Article•
TL;DR: Based on the sensitive detection of chromosome abnormalities by FISH, more accurate correlations between chromosome abnormalities and prognosis can be performed, and specific aberrations of clinical significance will likely be identified by the systematic application of interphase cytogenetics on a large series of patients.
Abstract: The most frequent chromosome aberrations in B cell chronic lymphocytic leukemia (B-CLL) detected by conventional chromosome banding analysis are trisomy 12 followed by structural abnormalities of the long arms of chromosomes 13, 14, and 11. Complex karyotypes, trisomy 12, and a '14q+' abnormality have been associated with inferior prognosis, whereas aberrations of 13q have been found in patients with a favorable outcome. However, the cytogenetic analysis of B-CLL by conventional banding techniques has remained a difficult task mainly due to the low in vitro mitotic activity of the tumor cells. Although B cell mitogens are used for cell culture, clonal chromosome aberrations are detected in only half of the B-CLL tumors. 'Interphase cytogenetics' by means of fluorescence in situ hybridization (FISH) circumvents this problem, because there is no need to induce the malignant cells to proliferate in vitro. Numerical and structural chromosome aberrations can be detected in non-dividing interphase cells as well as in metaphase spreads. By FISH, the most common chromosome abnormalities are deletions of 13q followed by deletions of 11q, trisomy 12, and deletions of 17p. Except for the TP53 gene at 17p13, no candidate gene affected by these aberrations has so far been identified. FISH will be instrumental for the identification of such genes because the recurrent aberrations, especially deletions, can be systematically delineated to the resolution level of several kb. Furthermore, based on the sensitive detection of chromosome abnormalities by FISH, more accurate correlations between chromosome abnormalities and prognosis can be performed. Deletion of the TP53 gene at 17p13 have already been shown to be one of the most important independent prognostic factors for survival. Other specific aberrations of clinical significance will likely be identified by the systematic application of interphase cytogenetics on a large series of patients.
Journal Article•
TL;DR: Applying the set of microsatellite markers used in this study, a PCR-based diagnosis of chromophobe renal cell carcinomas could be established within 1 to 2 days and allows a correct genetic characterization in all cases where a diagnosis based on histopathology remains uncertain.
TL;DR: A comprehensive overview of chromosomal aberrations is presented with spectral karyotyping of human metaphase chromosomes using 24 chromosome-specific painting probes and the SpectraCube, which is able to retrieve spectral information for every pixel in a digital CCD image.
Abstract: Spectral karyotyping (SKY) is a new fluorescence in situ hybridisation (FISH) technique that refers to the molecular cytogenetic analysis of metaphase preparations by means of spectral microscopy. For SKY of human metaphase chromosomes, 24 chromosome-specific painting probes are used in just one FISH experiment. The probes are labelled by degenerate oligonucleotide-primed PCR using three fluorochromes and two haptens. Each probe is differentially labelled with one, two, three or four fluorescent dyes, resulting in a unique spectral signature for every chromosome. After in situ hybridisation and immunodetection, a spectral image is acquired using a conventional fluorescence light microscope equipped with a custom-designed triple-bandpass filter and the SpectraCube, which is able to retrieve spectral information for every pixel in a digital CCD image. The 24-colour display and chromosome classification are based on the unique emission spectra of the chromosomes. Together with chromosome banding information from an inverted DAPI or a G-banded metaphase, a comprehensive overview of chromosomal aberrations is presented.
TL;DR: Chances are, chromosomally abnormal cells can be found in the peripheral blood of both parapsoriasis en plaque and CTCL patients and can be detected with interphase cytogenetical methods, which obviates the need for dividing cells, often difficult to accomplish in C TCL.
TL;DR: Using fluorescence in situ hybridization (FISH), introduced genes on metaphase chromosomes of barley, wheat, and triticale transformed by microprojectile bombardment of microspores and scutellar tissue with the pDB1 plasmid containing the uidA and bar genes were localized.
Abstract: Using fluorescence in situ hybridization (FISH) we localized introduced genes on metaphase chromosomes of barley, wheat, and triticale transformed by microprojectile bombardment of microspores and scutellar tissue with the pDB1 plasmid containing the uidA and bar genes. Thirteen integration sites were detected in the nine lines analysed. Southern analysis showed that three or more copies of the plasmid were present in the lines. In a triticale line containing four copies three different integration sites were identified, indicating that the method described is sensitive enough for the detection of single-copy integrations. There was a slight tendency towards the localization of transgenes in distal chromosome regions. Using the GAA-satellite sequence for chromosome banding, the chromosomes containing the inserted genes were identified in most cases. Two barley lines derived from the same transformant showed a totally different integration pattern. Southern analysis confirmed that the inserted genes were segregating independently, resulting in different integration patterns among the progeny lines. The application of the FISH technique for the analysis of transgenic plants is discussed.
TL;DR: A unique patient with H-JEB, who was homozygous for a nonsense mutation, Q243X, in the LAMB3 gene on chromosome 1 and who had normal karyotype 46,XY, is described, the first description of uniparental disomy of human chromosome 1.
Abstract: Summary Junctional epidermolysis bullosa (JEB) is an autosomal recessive disorder characterized by blister formation at the level of the lamina lucida within the cutaneous basement-membrane zone. Classic lethal JEB (Herlitz type [H-JEB]; OMIM 226700) is frequently associated with premature-termination-codon mutations in both alleles of one of the three genes (LAMA3, LAMC2, or LAMB3) encoding the subunit polypeptides (a3, p3, and y2) of laminin 5. In this study, we describe a unique patient with H-JEB, who was homozygous for a nonsense mutation, Q243X, in the LAMB3 gene on chromosome 1 and who had normal karyotype 46, XY. The mother was found to be a carrier of the Q243X mutation, whereas the father had two normal LAMB3 alleles. Nonpaternity was excluded by use of 11 microsatellite markers from six different chromosomes. The use of 17 partly or fully informative microsatellite markers spanning the entire chromosome 1 revealed that the patient had both maternal uniparental meroisodisomy of a 35-cM region on 1q containing the maternal LAMB3 mutation and maternal uniparental heterodisomy of other regions of chromosome 1. Thus, the results suggested that reduction to homozygosity of the 1q region containing the maternal LAMB3 mutation caused the H-JEB phe-notype. The patient was normally developed at term and did not show overt dysmorphisms or malformations. This is the first description of uniparental disomy of human chromosome 1.
TL;DR: Interestingly, this family is the fifth unrelated family to be reported with a balanced reciprocal translocation between the short arms of chromosomes 5 and 11 and is suggestive of sequence homology between the two chromosome regions involved in the translocation.
Abstract: We present a three generation family in which a father and son have a balanced chromosome translocation between the short arms of chromosomes 5 and 11 (karyotype 46,XY,t(5;11)(p15.3;p15.3)). Two family members have inherited the unbalanced products of this translocation and are trisomic for chromosome 11p15.3-->pter and monosomic for chromosome 5p15.3-->pter (karyotype 46,XY,der(5)t(5;11)(p15.3;p15.3)pat). Paternally derived duplications of 11p15.5 are associated with Beckwith-Wiedemann syndrome (BWS) and both family members trisomic for 11p15.5 had prenatal overgrowth (birth weights >97th centile), macroglossia, coarse facial features, and broad hands. We review the clinical features of BWS patients who have a paternally derived duplication of 11p15.5 and provide evidence for a distinct pattern of dysmorphic features in those with this chromosome duplication. Interestingly, our family is the fifth unrelated family to be reported with a balanced reciprocal translocation between the short arms of chromosomes 5 and 11. The apparently non-random nature of this particular chromosome translocation is suggestive of sequence homology between the two chromosome regions involved in the translocation.