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Clinical contribution to the knowledge of hemopoietic dysplasias: long-term follow-up of 13 patients with refractory anemia.

Refractory anemia (RA) is an hematologic disorder at risk of developing into a malignancy (hemopoietic dysplasia). Information on hemopoietic dysplasias is useful for sharpening the appropriate diagnostic criteria and for the search of an appropriate therapy. Moreover, hemopoietic dysplasias provide an interesting opportunity, in humans, for studying a developing leukemia, or a disease situated at the boundary of leukemia. This paper reports on the evolution of RA in 13 patients followed up more than 2 years, through clinical observation, blood and marrow examination, and karyotype analysis. 4 of these 13 patients developed acute or subacute myeloid leukemia. An additional patient died because of severe thrombocytopenia. In these 5 patients, dyserythropoiesis was accompanied by thrombocytopenia, marrow myeloblastosis, and nonrandom chromosome abnormalities.

Aged↗

Climate change and recent genetic flux in populations of Drosophila robusta.

BACKGROUND: Studied since the early 1940's, chromosomal polymorphisms in the deciduous woods species Drosophila robusta have been characterized by well-defined latitudinal, longitudinal, and elevational clines, but--until at least ten years ago--stable, local population frequencies. Recent biogeographical analyses indicate that D. robusta invaded North America from southeast Asia and has persisted in eastern temperate forests for at least 20-25 my without speciating. The abundant chromosome polymorphisms found across the range of D. robusta are thus likely to be relatively ancient, having accumulated over many well known climatic cycles in North America. Sufficient long-term data are now available such that we can now gauge the rate of these evolutionary changes in natural populations due to environmental change. RESULTS: Recent local collections have revealed significant changes in the frequencies of several chromosomal forms. New data presented here extend the range of these changes to six states, three in the northeastern United States and three west of the Mississippi River. These data reinforce recent directional changes in which the frequencies of three gene arrangements have reached percentage levels typical of distant southern populations consistent with regional climatic changes. Another gene arrangement has been steadily decreasing in frequency at a number of the sites studied. Meteorological records from 1945 to 2003 indicate temperature increases at all study sites, particularly average minimum air temperatures. CONCLUSIONS: Observation of parallel genetic flux suggests that these long-term temporal frequency shifts in widely disparate populations of D. robusta are evolutionary responses to environmental change. Since these chromosomes are known to be sensitive to ambient temperature, regional climatic shifts associated with global warming are likely to be responsible.

Analysis of Variance↗

Hybridization, transgressive segregation and evolution of new genetic systems in Drosophila.

Introgressive hybridization facilitates incorporation of genes from one species into the gene pool of another. Studies on long-term effects of introgressive hybridization in animal systems are sparse. Drosophila nasuta (2n = 8) and D. albomicans (2n = 6)-a pair of allopatric, morphologically almost identical, cross-fertile members of the nasuta subgroup of the immigrans species group-constitute an excellent system to analyse the impact of hybridization followed by transgressive segregation of parental characters in the hybrid progeny. Hybrid populations of D. nasuta and D. albomicans maintained for over 500 generations in the laboratory constitute new recombinant hybrid genomes, here termed cytoraces. The impact of hybridization, followed by introgression and transgressive segregation, on chromosomal constitution and karyotypes, some fitness parameters, isozymes, components of mating behaviour and mating preference reveals a complex pattern of interracial divergence among parental species and cytoraces. This assemblage of characters in different combinations in a laboratory hybrid zone allows us to study the emergence of new genetic systems. Here, we summarize results from our ongoing studies comparing these hybrid cytoraces with the parental species, and discuss the implications of these findings for our understanding of the evolution of new genetic systems.

Animals↗

Comprehensive cytogenetic analysis including multicolor spectral karyotyping and interphase fluorescence in situ hybridization in lymphoma diagnosis. a summary of 154 cases.

Cytogenetic analysis including multicolor spectral karyotyping (SKY) and interphase fluorescence in situ hybridization (FISH) was performed on 154 consecutive cases with suspected lymphoma. The cytogenetic results were reviewed in correlation with the final pathologic diagnosis. A diagnosis of lymphoma was established in 94 cases, with 16 Hodgkin lymphomas and 78 non-Hodgkin lymphomas (NHL). Cytogenetic results were obtained in 63 NHLs (81%); 61 of those showed abnormal karyotypes (97%). The t(14;18) or IGH-BCL2 fusion was detected in 83% (20/24) of follicular lymphomas and in 57% (12/21) of diffuse large B-cell lymphomas (DLBCL). The application of interphase FISH and SKY has contributed to a high detection rate of t(14;18) in DLBCLs. This study showed that genes at 1q25, 3p21, 3q21, 5q31, 6p23, 7q22, 8q11 approximately q12, 9q34, 11q23, 12q13, and 19q13.1 may have been involved as the less common changes in follicular lymphoma and DLBCL. Comparison of the recurrent secondary aberrations in the groups of follicular lymphoma and DLBCL revealed a pattern of clonal evolution from the changes rea(1)(p36), del(6q), +7, +12 or dup or trp(12)(q13q22), +der(18)t(14;18), and +21 in follicular lymphoma to the changes rea(1)(p36), del(6q), +6, +7, +9, rea(11)(q23), +12, -13 or del(13(q12q14), +18, +21, and +X in DLBCL. The clonal evolution of the secondary aberrations is thought to contribute to the progression of the disease. About 90% (16/18) of other types of NHL had abnormal karyotypes showing specific translocations or gene rearrangements consistent with the pathologic diagnosis. A comprehensive cytogenetics approach including SKY and interphase FISH using probes for specific genes, such as IGH, BCL2, CCND1, and ALK, is a very useful ancillary diagnostic tool for lymphomas. The combined approach also led to the identification of t(2;19)(p23;q13.1) as a new variant of t(2;5)(p23;q35) in a case of Ki-1-positive anaplastic large cell lymphoma with a null cell phenotype.

Chromosome Aberrations↗

[Correlations between Ph 1 clone and leukocyte alkaline phosphatase on their associaton: chronic myeloid leukemia and pregnancy].

A biological [karyotype, leucocyte alkaline phosphatase (L.A.P.), haematimetry] and clinical study was performed on three women carriers of a chronic myaloid leukemia during their pregnancy (3 1/2 months, 6 1/2 months), or just after delivery. The results show : (1) a relation between the acuteness of the illness and a higher rate of L.A.P., probably secondary to pregnancy, and (2) a relation between the clinical evolution and the rate of Ph1 (+) cells.

Adult↗

Cytogenetics of the parthenogenetic grasshopper Warramaba virgo and its bisexual relatives. VIII. Karyotypes and C-banding patterns in the clones of W. virgo.

Eleven cytological clones of the parthenogenetic grasshopper Warramaba virgo are defined in this paper on the basis of their karyotypes and the C-banding patterns of their chromosomes. These clones are additional to the 16 clones previously described. Seven of the new clones have the standard karyotype and differ only in minor features of the C-bands, the result of amplification or diminution of heterochromatic segments. The remaining 4 clones carry translocations. Of the total of 27 clones of W. virgo now known, 9 carry translocations or fusions. The X + A chromosome is involved in five of these rearrangements and the 1(169) chromosome in four, suggesting a marked nonrandomness with regard to involvement in rearrangements. All the clones with translocations or fusions are known from single localities, suggesting that they are short-lived and do not spread far from their point of origin. A clone that apparently carries a paracentric inversion in one chromosome is more widespread. Clonal diversity in W. virgo seems to be maximal in the Kalgoorlie region of Western Australia, where W. virgo is believed to have arisen, on two separate occasions, by hybridization between two bisexual species. A classification of the clones on the basis of their C-banding patterns is tentatively proposed.

Animals↗

t(18;22)(q21;q11) with rearrangement of BCL2 as a possible secondary change in a lymphocytic lymphoma.

We report a lymphocytic lymphoma showing a combination of two characteristic neoplasia-associated chromosomal changes: trisomy 12, commonly observed in chronic lymphocytic leukemia and lymphocytic lymphoma, and t(18;22)(q21;q11), a variant form of the t(14;18)(q32;q21) found in most follicular lymphomas. Southern blot analysis was performed using probes for the 5' end of the BCL2 gene (18q21) and for the J lambda as well as C lambda immunoglobulin genes (22q11). With these two probes, a unique rearranged fragment was detected. Thus the t(18;22)(q21;q11) can be considered as a variant translocation of t(14;18)(q32;q21). The karyotypic analysis supports the assumption that in our case trisomy 12 occurred first, and t(18;22) appeared during tumor progression as part of the clonal evolution. This is at variance with the typical t(14;18), which has never been found to occur as a secondary change.

Blotting, Southern↗

G-banding analysis of complex aneuploidy in multiple myeloma bone marrow cells.

Chromosome studies with the banding technique have been performed in a considerable number of cases of myeloproliferative diseases, but technical difficulties have so far prevented detailed studies of chromosomal abnormalities in multiple myeloma. The karyotypes of bone marrow cells from two patients with multiple myeloma have been analyzed by a trypsin-Giemsa banding technique. Evidence is given for clonal evolution which in one patient has probably occurred by cell fusion and subsequent chromosome loss. Eight different marker chromosomes are characterized. Nonrandom chromosomal participation in the translocations and the existence of specific vulnerable points on chromosomes 1, 3, and 16 are suggested.

Aged↗

Comparative genomic in situ hybridization (cGISH) analysis on plant chromosomes revealed by labelled Arabidopsis DNA.

A new approach for comparative cytogenetic banding analysis of plant chromosomes has been established. The comparative GISH (cGISH) technique is universally applicable to various complex genomes of Monocotyledonae (Triticum aestivum, Agropyron elongatum, Secale cereale, Hordeum vulgare, Allium cepa, Muscari armenaticum and Lilium longiflorum) and Dicotyledonae (Vicia faba, Beta vulgaris, Arabidopsis thaliana). Labelled total genomic DNA of A. thaliana generates signals at conserved chromosome regions. The nucleolus organizing regions (NORs) containing the majority of tandemly repeated rDNA sequences, N-band regions containing satellite DNA, conserved homologous sequences at telomeres and additional chromosome-characteristic markers were detected in heterologous FISH experiments. Multicolour FISH analysis with repetitive DNA probes simultaneously revealed the chromosome assignment of 56 cGISH signals in rye and 61 cGISH signals in barley. Further advantages of this technique are: (1) the fast and straightforward preparation of the probe; (2) the generation of signals with high intensity and reproducibility even without signal amplification; and (3) no requirement of species-specific sequences suitable for molecular karyotype analysis. Hybridization can be performed without competitive DNA. Signal detection without significant background is possible under low stringency conditions. The universal application of this fast and simple one-step fluorescence banding technique for plant cytogenetic and plant genome evolution is discussed.

Arabidopsis↗

Congenital heart defects and chromosomal anomalies including 22q11 microdeletion (CATCH 22).

OBJECTIVE: To analyze the frequency of chromosomal anomalies or 22q11 microdeletion in patients with congenital heart defects and other congenital anomalies; to describe the clinical phenotype of children with the 22q11 microdeletion and with chromosomal anomalies; to evaluate patients' clinical evolution; and to provide genetic counseling for families. METHODS: The study included 46 patients with congenital heart defects and other anomalies and patients with a phenotype consistent with 22q11 microdeletion observed between 1999 and 2001. Confirmation of the heart defect was accomplished through echocardiography, magnetic resonance angiography or cardiac catheterization. Karyotyping with high resolution banding and detection of 22q11 microdeletion with FISH techniques were performed. We excluded patients with trisomy 21, 13 and 18, 45,X and deletion of 7q11.23. Patients with 22q11 microdeletion underwent immunology studies and evaluation of parathyroid function. Clinical evolution was evaluated. Chromosome and FISH studies were performed on parents of affected children (25 couples). RESULTS: Forty-six children were included, of whom twelve (26.1%) had chromosomal anomalies (group A), fourteen (30.4%) had 22q11 microdeletion (group B) and the remaining twenty (43.5%) had normal karyotype and negative FISH studies (group C). In group A septal heart defects predominated. This group had significant morbidity, with surgical correction in three patients, early development of pulmonary hypertension, failure to thrive and serious neurological problems. Two patients died. In group B conotruncal heart defects (7/14) and ventricular septal defects (5/14, two associated with cervical aortic arch) predominated. The most significant morbidity was related to cardiac pathology, with surgical correction in seven cases (50%). Immune function defects and parathyroid function problems were mild, requiring no therapeutic measures. One patient died. CONCLUSION: In the presence of heart defects associated with other congenital anomalies, karyotyping is mandatory and if clinical features are compatible, 22q11 microdeletion should be specifically sought with FISH techniques. Detection of chromosomal anomalies has a significant impact on prognosis and follow-up of patients, as well as on genetic counseling of families.

Child, Preschool↗

Comparative fluorescence in situ hybridization mapping of primate chromosomes with Alu polymerase chain reaction generated probes from human/rodent somatic cell hybrids.

We have used Alu polymerase chain reaction generated probes from rearranged human/rodent somatic cell hybrids for fluorescence in situ hybridization and comparative mapping of some intrachromosomal changes in the karyotypes of great apes (Pan troglodytes, P. paniscus, Gorilla gorilla, Pongo pygmaeus), a gibbon (Hylobates lar), and an Old World monkey (Macaca fuscata). Probes containing chromosomes 2 and 18 fragments confirmed inversions already suggested by the banding pattern of great ape homologues. However, a chromosome 3 fragment showed complex rearrangements in the gibbon and macaque karyotype which were previously not well defined from banding. 'Subchromosomal painting' will allow the identification of intrachromosomal changes on the basis of DNA homology and provides a powerful method to study karyological and genomic evolution.

Animals↗

Mobile elements and chromosomal evolution in the virilis group of Drosophila.

Species of the virilis group of Drosophila differ by multiple inversions and chromosome fusions that probably accompanied, or led to, speciation. Drosophila virilis has the primitive karyotype for the group, and natural populations are exceptional in having no chromosomal polymorphisms. We report that the genomic locations of Penelope and Ulysses transposons are nonrandomly distributed in 12 strains of D. virilis. Furthermore, Penelope and Ulysses insertion sites in D. virilis show a statistically significant association with the breakpoints of inversions found in other species of the virilis group. Sixteen newly induced chromosomal rearrangements were isolated from the progeny of D. virilis hybrid dysgenic crosses, including 12 inversions, 2 translocations, and 2 deletions. Penelope and Ulysses were associated with the breakpoints of over half of these new rearrangements. Many rearrangement breakpoints also coincide with the chromosomal locations of Penelope and Ulysses insertions in the parental strains and with breakpoints of inversions previously established for other species of the group. Analysis of homologous sequences from D. virilis and Drosophila lummei indicated that Penelope insertion sites were closely, but not identically, located at the nucleotide sequence level. Overall, these results indicate that Penelope and Ulysses insert in a limited number of genomic locations and are consistent with the possibility that these elements play an important role in the evolution of the virilis species group.

Animals↗

Cytogenetic and flow cytometry DNA analysis of regional heterogeneity in a low grade human glioma.

This study combined flow cytometry with standard cytogenetic analysis of first division cells to evaluate regional heterogeneity in 38 spatially mapped regions of a low grade human oligoastrocytoma. Histologically, the tumor was relatively homogeneous. In contrast, flow cytometry and cytogenetic analyses identified variable percentages of near-diploid (ND; 35 to 57 chromosomes/metaphase) and near-tetraploid (81-103 chromosomes/metaphase) populations. The largest proportion of cells in the ND population was 46,XY with normal Giemsa bands; however, four karyotypically unrelated ND clones also were identified. The development of these clonal populations centered around a region in which more than 50% of the cells contained nonclonal abnormalities and which demonstrated more histological pleomorphism than any other region. The frequency of the nonclonal karyotypes suggested that this region was genetically unstable. Three of the clonal ND populations resided in small, spatially discreet areas of the tumor. The largest and the most widely distributed clonal population, 47,XY,+7, underwent further evolution to give rise to seven additional sidelines. This investigation demonstrates that low grade gliomas have areas of genetic instability capable of generating mutant cells with the capacity to proliferate and to form cellular foci. As a result, multiple, spatially distinct clonal populations can exist in low grade gliomas, some of which are capable of further cytogenetic evolution and clonal expansion, resulting in tumor progression.

Adult↗

Pulsed-field gel electrophoresis.

Pulsed-field gel electrophoresis (PFGE) was originally developed as a technique for providing electrophoretic karyotypes of micro-organisms. Since then the technique has evolved and diversified in many new directions. This review traces the evolution of PFGE, summarizes our understanding of its theoretical basis, and provides a comprehensive description of the methodology. Established and novel applications are explored and the reader is provided with an extensive list of references.

DNA↗