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1.
The inheritance complex chromosome translocation is a rare. A familial complex chromosome rearrangement t(1;4;10)(q21.3;q27;q26.1) involving three chromosomes ascertained due to four spontaneous abortions in phenotypically normal childless woman there is presented. Cytogenetic analysis according to classic banding techniques were verified by fluorescent in situ hybridization (FISH) technique.  相似文献   

2.
We describe perinatal findings in a female fetus with partial trisomy 8q(8q24.1-->8qter) and partial monosomy 15q(15q26.1-->15qter) resulting from a paternal t(8;15) reciprocal translocation. Prenatal sonographic examination showed intra-uterine growth retardation, bilateral ventriculomegaly, cardiomegaly with arrhythmia, anhydramnios, and absent kidney and urinary bladder images. The pregnancy was terminated at 28 weeks of gestation. At birth, the infant manifested typical dysmorphic features of partial trisomy 8q. Necropsy further revealed hydrocephalus, congenital diaphragmatic hernia, ventricular septal defect, a horseshoe kidney with renal hypoplasia, and kyphoscoliosis. Our case shows that the coexistence of partial trisomy 8q24.1-->8qter and partial monosomy 15q26.1-->15qter are more detrimental than either defect alone and can result in a complex of major malformations. Prenatal ultrasound examination and cytogenetic assessment should be offered in subsequent pregnancies.  相似文献   

3.
We report on a case of constitutional mosaicism for a large pericentric inversion of chromosome 9 in a man whose daughter had recombinant aneusomy resulting in partial 9q duplication and partial 9p deletion. At age 6 months, the girl was evaluated because of congenital anomalies [corrected] and developmental delay. Chromosomal analysis on this infant showed a derivative chromosome 9 which was later determined to be a recombinant chromosome with trisomy of 9q34.1-->qter and monosomy of pter-->9p24. Chromosomal analysis in her father showed the presence of two cell lines; 75% of lymphocytes had a 46,XY pattern, and 25% had a 46,XY,inv(9)(p24q34.1) karyotype. The infant's physical findings represent a composite of the reported cases of both trisomy 9q34.1-->qter and monosomy pter-->9p24. The infant's father was phenotypically and cognitively normal. This case broadens the spectrum of reported cases of mosaicism for an autosomal structural rearrangement generating unbalanced gametes, and further supports the tenet that constitutional mosaicism has clinical relevance for genetic counseling.  相似文献   

4.
Fluorescence in situ hybridization (FISH) using chromosome-specific DNA libraries as painting probes, locus-specific unique sequence (cosmid) probes, and Y-specific repetitive sequences was applied in the analysis of eighteen cases of chromosomal rearrangements of undetermined nature. FISH clarified the origin of the extra or translocated chromosome segments in seventeen patients, one with 2q+, two with 4q+, one each with 6p+, 7p+, 9q+, 10p+, 11q+ and 12p+, two with 13q+, and one each with 15q+, 17p+, 18p+, 20p+, 21p+ and Yq+, as well as the nature of a de novo supernumerary chromosome marker in a previously reported case. By G-banding and molecular cytogenetic studies of the family members, six cases were determined to have unbalanced translocations inherited from the carrier parent. The extra translocated genetic material may cause specific trisomic syndromes, including partial 6p21.3-p23, 9q32-q34.3, 13q32-q34, 15q24-q26, and 17p11.2-p13 trisomies in those patients. A translocated 21q segment on 12p was shown by a painting probe in a patient with Down features. A patient with cat cry syndrome resulting from a loss of the terminal segment of the short arm of chromosome 5 was confirmed by a cosmid probe showing de novo reciprocal translocation between chromosomes 5 and 18:t(5;18) (p13.3;p11.31). With FISH, the extra material on the rearranged chromosome could also be identified as duplicated or translocated. The FISH technique thus provides a method for the analysis of extra structurally abnormal chromosomes (especially in de novo cases), recognizable syndromes (contiguous gene syndromes) caused by translocated deletion from parental balanced chromosome rearrangements, and supernumerary marker chromosomes. FISH subsequent to G-banding is also of great help in the confirmation of preliminary abnormal G-banded karyotypes after a modified destaining procedure. In conclusion, the combination of G-banding and FISH is very useful in the accurate diagnosis of chromosomal rearrangements.  相似文献   

5.
DNA cytofluorometry and fluorescence in situ hybridization (FISH) with centromeric repetitive probes of chromosomes 1, 7, 11, 17, X and Y were used to detect numerical chromosomal aberrations in 13 squamous cell carcinomas of the tongue. In 4 of the 6 DNA-diploid tumors examined, significant numerical aberrations in at least 1 of the chromosomes were detected. The main line of 1 tumor showed trisomy 1 and the other 3 tumors had significant sublines that showed trisomy or monosomy of the 1 or 2 chromosomes examined. No common specific aberrations were detected in these tumors. Cytofluorometrically we found polyploidy in all 4 of the tumors with numerical chromosomal aberrations. These results suggest that subpopulations which are aneuploid at the chromosome level arise preferentially from DNA-diploid tumors with polyploidy before the ploidy of the main line shifts to overt DNA-aneuploidy. In all of the 7 DNA-aneuploid tumors examined, we detected numerical chromosomal aberrations. Most of the aberrations were thought to occur after tetraploidization because a gain in chromosomal copy number including tetrasomy was common. In 3 DNA-aneuploid tumors, however, the main line showed disomy 11, whereas the other chromosomes examined had 3 or more copies. In 1 of the 3 tumors there was a significant subline of monosomy 11. In these 3 tumors disomy 11 may have been preceded by a DNA-diploid stage with monosomy 11 before tetraploidization.  相似文献   

6.
To examine at which stage in the multistep process of head and neck tumorigenesis numerical chromosomal alterations can be detected by fluorescence in situ hybridization (FISH), biopsies and cell smear preparations of clinically healthy oral tissue, premalignant lesions (leukoplakias), and tumors were analyzed by FISH using chromosome-specific centromeric probes. Aberrations found in tumor biopsies and in tumor cell smears consisted of trisomy of chromosomes 1, 7, 10, and 17 and monosomy of chromosomes 1, 7, 9, 10, and 17. In five of eight dysplastic oral leukoplakia biopsies, aberrations were seen consisting of trisomy of chromosome 1, 7, and 17, and monosomy of chromosome 9. No aberrations were found in biopsies of hyperplastic lesions (n = 8), or in oral cell smears of persons at risk. Because numerical chromosomal aberrations seem to be highly specific for malignant cells, FISH may help to identify leukoplakias that have a high risk of malignant conversion.  相似文献   

7.
The t(11;22) (q23;q11) translocation is the most frequently identified familial reciprocal translocation in humans. In translocation carriers, 3:1 meiotic segregation with tertiary trisomy can occur resulting in abnormal progeny with the der(22) as the supernumary chromosome. Affected children have a distinct phenotype with multiple anomalies and severe mental retardation. We have identified a child with developmental delay and multiple anomalies consistent with the der(22) phenotype. Cytogenetic analysis showed an abnormal chromosome complement of 47,XX,+der(22)t(11;22)(q23; q11) in all 50 cells analysed. FISH analysis using chromosome 11 and 22 painting probes showed a pattern consistent with a reciprocal translocation of the distal bands 11q23 and 22q11 respectively. Parental karyotypes were normal. RFLP analysis of locus D22S43, which maps above the t(11;22) breakpoint, showed that the der(22) was paternal in origin and indicated that the normal chromosomes 22 were the probable result of maternal heterodisomy. RFLP analysis of locus D22S94, which maps below the t(11;22) breakpoint, also suggested that both normal chromosomes 22 of the child represented the two maternal homologues. Non-paternity was excluded through the analysis of 10 microsatellite markers distributed on 10 different chromosomes and three VNTRs on three different chromosomes. To the best of our knowledge, this is the first reported case of a patient with an abnormal karyotype resulting from a de novo translocation in the paternal germline with probable unbalanced adjacent 1 segregation and maternal non-disjunction of chromosome 22 in meiosis I.  相似文献   

8.
Juvenile myelomonocytic leukemia (JMML) is a rare disorder of early childhood, to which no recurrent chromosome rearrangement has been yet associated. We report a case where leukemic cells harbored a 46,XX,der(12)t(3;12) (q21 approximately 22;p13.33) karyotype, resulting in partial trisomy of 3q. The origin of chromosome material translocated to chromosome 12 was assessed by chromosome painting using a whole chromosome 3-specific probe. The breakpoint regions were defined by FISH using YAC probes from 3q and 12p chromosomal regions. Interestingly, partial trisomy of 3q has been detected in a previously reported JMML case, consequent to the presence of a der(15)t(3;15)(q13.1;q26). The involvement of a similar chromosome 3 rearrangement in these two JMML cases suggests the hypothesis that either the resulting duplication of some gene/s on 3q or the loss of heterozygosity (LOH) of some gene/s on 3p may be involved in one of the steps leading to JMML. On the other hand, it cannot be ruled out that the relevant mutation in our case might be consequent to the particular breakpoints at bands 3q21 approximately 22 and 12p13.3, that may alter the structure and/or expression of the involved gene/s.  相似文献   

9.
A case of partial trisomy 9 is described in a mentally retarded and dysmorphic child, confirming that this chromosome unbalance results in a characteristic clinical entity. This trisomy arose through aberrant segregation of translocation chromosome during meiosis in the patient's mother, who is a balanced heterozygote for a complex translocation involving chromosomes 9, 21 and 22. The phenotypically normal sister of the proposition is also carrier of the same complex translocation.  相似文献   

10.
Fluorescence in situ hybridization (FISH) is a powerful tool for detection of numerical and structural chromosomal aberrations. We have compared conventional banding techniques and FISH for the detection of monosomy 7 (-7) and trisomy 8 (+8) in 89 patients with myeloid malignancies. Of these patients, 21 had -7, 30 had +8, four had both, and 34 had no aberrations or aberrations other than -7 or +8 as assessed by banding techniques. Sequential samples were available in 23 patients. Alphoid DNA probes specific for chromosomes no. 7 and 8 were used for FISH. As controls, 10 normal bone marrow (BM) samples were hybridized with the chromosomes no. 7 and 8 probes, and in addition all tumor samples were hybridized with a chromosome no. 1 specific probe. The cut-off value for -7 was 18% one-spot cells, and for +8 was 3% three-spot cells. FISH analysis of 44 samples with -7 or +8, and at least 10 metaphases evaluated, showed that the proportions of aberrant metaphase cells mirrored the interphase clone sizes. Most samples with nonclonal metaphase aberrations, including those with only a few metaphases, had increased numbers of aberrant interphase cells: 20% to 80% for -7, and 3% to 43% for +8. Interphase cytogenetics of the 34 samples without -7 or +8 did not show significant cell populations with -7 or +8. In four patients, -7 or +8 could not be confirmed by FISH due to additional structural aberrations, marker chromosomes, or wrongly interpreted banding results. As FISH will be used more and more in cytogenetic diagnosis, clinical follow-up, and therapy monitoring, it will be necessary to standardize FISH procedures and supplement the Standing Committee on Human Cytogenetic Nomenclature (ISCN) definitions of a clone with criteria specifically for in situ hybridization.  相似文献   

11.
We report the characterization of a de novo unbalanced chromosome rearrangement by comparative genomic hybridization (CGH) in a 15-day-old child with hypotonia and dysmorphia. We describe the combined use of CGH and fluorescence in situ hybridization (FISH) to identify the origin of the additional chromosomal material on the short arm of chromosome 6. Investigation with FISH revealed that the excess material was not derived from chromosome 6. Identification of unknown unbalanced aberrations that could not be identified by traditional cytogenetics procedures is possible by CGH analysis. Visual analysis of digital images from CGH-metaphase spreads revealed a predominantly green signal on the telomeric region of chromosome 10p. After quantitative digital ratio imaging of 10 CGH-metaphase spreads, a region of gain was found in the chromosome band 10p14-pter. The CGH finding was confirmed by FISH analysis, using a whole chromosome 10 paint probe. These results show the usefulness of CGH for a rapid characterization of de novo unbalanced translocation, unidentifiable by karyotype alone.  相似文献   

12.
We present the perinatal findings of a fetus with a de novo unbalanced chromosome translocation that resulted in monosomy for proximal 14q and monosomy for distal 4p. Prenatal sonographic examination at 27 weeks of gestation showed intrauterine growth retardation, microcephaly, cardiomegaly with arrhythmia, and asymmetry of the upper limbs. Genetic amniocentesis showed an abnormal karyotype of 45,XX,der(4)t(4;14)(p16.3;q12),-14. Linkage analysis of the family confirmed the maternal origin of the deletions. Molecular refinement of the deletion breakpoints indicated that the breakpoints at 4p16.3 and 14q12 were located between loci D4S403 (present) and D4S394 (absent), and between loci D14S252 (present) and D14S64 (absent), respectively. Necropsy showed dysmorphic features compatible with Wolf-Hirschhorn syndrome, hypertrophic cardiomyopathy, partial hemihypoplasia, and a normal brain without evidence of holoprosencephaly. Our case adds to the list of clinical phenotypes associated with the proximal regions of 14q.  相似文献   

13.
Chromosomes from 20 patients were used to delineate the breakpoints of inverted duplications of chromosome 15 (inv dup[15]) that include the Prader-Willi syndrome/Angelman syndrome (PWS/AS) chromosomal region (15q11-q13). YAC and cosmid clones from 15q11-q14 were used for FISH analysis, to detect the presence or absence of material on each inv dup(15). We describe two types of inv dup(15): those that break between D15S12 and D15S24, near the distal boundary of the PWS/AS chromosomal region, and those that share a breakpoint immediately proximal to D15S1010. Among the latter group, no breakpoint heterogeneity could be detected with the available probes, and one YAC (810f11) showed a reduced signal on each inv dup(15), compared with that on normal chromosomes 15. The lack of breakpoint heterogeneity may be the result of a U-type exchange involving particular sequences on either homologous chromosomes or sister chromatids. Parent-of-origin studies revealed that, in all the cases analyzed, the inv dup(15) was maternal in origin.  相似文献   

14.
In contrast to low-grade B-cell lymphomas originating in the gastrointestinal (GI) tract, only few cytogenetic data are available for the large cell, highly malignant variants. We studied 31 large B-cell lymphomas of the GI tract by comparative genomic hybridization (CGH) and fluorescence in situ hybridization using specific DNA probes (FISH). The most frequent aberrations were gains of all or of parts of chromosomes 11 (11 cases), 12 (9 cases), 1q (4 cases), and 3q (4 cases). Losses of parts of chromosome 6q and of parts of the short arm of chromosome 17 (6 cases each) were found most frequently. In four cases a total of seven high-level DNA amplifications was detected. In two of these cases, involvement of specific protooncogenes (REL and MYC) was shown. Some genetic aberrations seemed to be associated with an inferior clinical course: patients with >/=2 aberrations had a significantly shorter median survival. Furthermore, all patients with gains of all or parts of chromosome arm 1q and with high-level DNA amplifications as well as seven of nine patients with gains of all or parts of chromosome 12 died of lymphoma. In conclusion, the pattern of chromosomal gains and losses in large B-cell lymphomas was different from data reported for low-grade (MALT) lymphomas of the stomach and bowel, especially with respect to the high incidence of partial gains of chromosome arm 11q and of all or parts of chromosome 12 and the low frequency of polysomy 3. In addition, our data suggest that chromosomal gains and losses detected by CGH and FISH may predict for the outcome of patients with this tumor entity.  相似文献   

15.
Rhim et al. were first to show that superinfection of Ad12-SV40-infected immortalized human epidermal cells with an RNA tumor virus containing a ras oncogene, such as Ki-MSV, or their treatment with chemical carcinogens, leads to the ability of cells to both grow in anchorage-independent fashion and to form tumors in athymic nude mice. We describe details of the chromosome changes observed during the transformation. The culture was monitored through 40 passages after Ad12-SV40 infection. Chromosomes 9 and 11 showed random monosomy during the initial stages, but by passage 10 clonal evolution of the cell line was well established. Observed chromosome monosomy/trisomy coupled with chromosome rearrangements (identified as chromosomes A through F) were monosomy 13, loss of p arms of 8 and 10, partial loss of 5 (del(5)(q13) and of the q arm of 18(del(18)(q12)), and extra copies of 11q, 20 and 21. During its progression to tumorigenicity, a derived chromosome E containing a segment of 5q, also appeared to play a major role. The cells remained immortalized as long as the 5q segment was present in some of the cell population as derived chromosomes E or F. Derivative chromosome E showed noteworthy changes during the progression to tumorigenicity, in both viral and chemical transformations. There was loss of heterozygosity of 5q due to an exchange of 5q with chromosomes E or F. In Ki-MSV- and 4NQO-transformed cells, presence of an altered chromosome E (identified as E1) was observed. In MNNG-treated cells, there was a selection of population of cells with further alteration in chromosome E (identified as E3). Besides alterations in chromosome E, additional chromosome changes leading to gene activation and amplification indicating a multistep progression to tumorigenicity were observed. The cytogenetic data reiterate the ever-increasing need for molecular analysis of nonrandom karyotype changes.  相似文献   

16.
We report the use of dual-colour chromosome painting to determine the exact nature of certain chromosome rearrangements observed in the pig (Sus scrofa domestica). The chromosomal abnormalities were detected by GTG- and RBG-banding techniques. The initially proposed interpretations were: (1) rcp(6;13)(p1.5;q4.1); (2) rcp(11;16)(p1.4;q1.4); (3) rcp(6;16)(p1.1;q1.1); (4) rcp(13;17)(q4.1;q1.1); (5) rcp(6;14)(q2.7;q2.1); (6) rcp(3;5)(p1.3;q2.3); (7) rcp(2; 14)(q1.3;q2.7); (8) rcp(15;17)(q1.3;q2.1). Hybridizations were carried out with biotin- and digoxigenin-labelled probes obtained by priming authorizing random mismatches polymerase chain reaction (PARM-PCR) amplification of porcine flow-sorted chromosomes. In some cases, i.e. (1), (4), (5), (6), (7) and (8), the fluorescence in situ hybridization (FISH) results allowed confirmation of the interpretations proposed with classical cytogenetic methods. Chromosome painting proved the reciprocity of the translocation in cases (1), (6) and (8), whereas modifications of the formula were proposed for case (2). Primed in situ DNA labelling (PRINS) experiments have also been carried out in case (3) using a primer specific for the centromeres of acrocentric chromosomes (first experiment) or a primer specific for the centromeres of a subset of meta- and submetacentric chromosomes including chromosome 6 (second experiment). It allowed us to demonstrate that the breakpoints occurred in the centromeric region of chromosome 16 and in the p. arm of chromosome 6, just above the centromere.  相似文献   

17.
We analysed a complex translocation involving chromosomes 5, 6, 8 and 11 in a case of infant leukemia. Molecular analysis of the MLL gene revealed that MLL was fused with two different genes, AF-6 on chromosome 6q27 and AF-5alpha. AF-5alpha, the 11th partner gene fused with MLL, is a novel gene mapped to chromosome 5q12, which encodes a 31 kDa protein of 269 amino acids and contains a possible nuclear targeting sequence, a potential leucine zipper dimerization motif and an alpha-helical coiled-coil domain. In situ hybridization and molecular cloning analyses demonstrated that two different types of chromosomal recombination had occurred in the cells. One was a three-way translocation among chromosomes 6, 8 and 11, and the other was an insertion of a chromosome 5-derived segment into the breakpoint of chromosomes 8 and 11. Accordingly, the karyotype was defined as del(5)(q11.2q12), der(6)t(6;8) (q27;q11.2), der(8)(8pter-->8q11.2::5q11.2-->5q12::11q23-->++ +11qter), der(11)t(6;11) (q27;q23). Thus, the MLL gene created two different fusion mRNAs, since the chromosome 11 split into two different chromosomes 5 and 6. This is the first report demonstrating fusion of the MLL gene with two different genes by a complex translocation.  相似文献   

18.
We report the prenatal exclusion of partial trisomy in a family with maternal pericentric inversion of chromosome 21 by fluorescence in situ hybridization (FISH). After determining the structural rearrangement in the mother and her affected son with 46,XY,rec(21)dup(21q)inv(21)(p11q22) resulting in Down syndrome (DS), a chorionic villus sample from the current pregnancy was analysed for the copy number of the DS critical region with a cosmid contig. The signal distribution was normal and the cytogenetic analysis revealed that the fetus had inherited the inverted chromosome 21 in a balanced form. FISH probes specific for the DS region are of great value in supporting cytogenetic results, regardless of the structural status of chromosome 21.  相似文献   

19.
We present the first report of a female fetus with concomitant isochromosome 18q [i(18q)] and cloacal dysgenesis sequence. Prenatal sonographic examination at 15 weeks' gestation showed intra-uterine growth retardation, a normal brain, a normal spine, congenital megacystis and oligohydramnios. The pregnancy was terminated. The abortus displayed dysmorphic features of a high forehead, hypertelorism, a prominent nose with a bulbous tip, median cleft lip and palate, micrognathia, low-set ears, a short neck, a joint contracture at the wrist, prominent heels and pseudo-hermaphroditism. Necropsy confirmed an imperforate anus, megacystis, a phallic structure and cloacal dysgenesis sequence. Postnatal chromosomal investigation proved a pure de novo i(18q). Molecular genetic analysis by polymorphic microsatellite markers confirmed the maternal origin of the aberrant chromosome. The coexistence of cloacal dysgenesis sequence and i(18q) in this case shows a correlation between the disturbance of the caudal developmental field and the chromosomal abnormality with monosomy 18p and trisomy 18q. Our presentation also demonstrates the importance of perinatal cytogenetic analysis in malformed fetuses in order to uncover underlying genetic disorders.  相似文献   

20.
Twenty-nine nonendocrine pancreatic carcinomas (20 primary tumors and nine metastases) were studied by chromosome banding after short-term culture. Acquired clonal aberrations were found in 25 tumors and a detailed analysis of these revealed extensive cytogenetic intratumor heterogeneity. Apart from six carcinomas with one clone only, 19 tumors displayed from two to 58 clones, bringing the total number of clones to 230. Karyotypically related clones, signifying evolutionary variation, were found in 16 tumors, whereas unrelated clones were present in nine, the latter finding probably reflecting a distinct pathogenetic mechanism. The cytogenetic profile of pancreatic carcinoma was characterized by multiple numerical and structural changes. In total, more than 500 abnormal chromosomes, including rings, markers, homogeneously stained regions, and double minutes, altogether displaying 608 breakpoints, were detected. This complexity and heterogeneity notwithstanding, a nonrandom karyotypic pattern can be discerned in pancreatic cancer. Chromosomes 1, 3, 6, 7, 8, 11, 12, 17, and 19 and bands 1q12, 1q21, 3q11, 6p21, 6q21, 7q11, 7q22, 7q32, 11q13, 13cen, 14cen, 17q11, 17q21, and 19q13 were most frequently involved in structural rearrangements. A total of 19 recurrent unbalanced structural changes were identified, 11 of which were not reported previously: del(1)(q11), del(3)(p11), i(3)(q10), del(4)(q25), del(11)(p13), dup(11)(q13q23), i(12)(p10), der(13;15)(q10;q10), del(18)(q12), del(18)(q21), and i(19)(q10). The main karyotypic imbalances were entire-copy losses of chromosomes 18, Y, and 21, gains of chromosomes 7, 2, and 20, partial or whole-arm losses of 1p, 3p, 6q, 8p, 9p, 15q, 17p, 18q, 19p, and 20p, and partial or whole-arm gains of 1q, 3q, 5p, 6p, 7q, 8q, 11q, 12p, 17q, 19q, and 20q. In general, the karyotypic pattern of pancreatic carcinoma fits the multistep carcinogenesis concept. The observed cytogenetic heterogeneity appears to reflect a multitude of interchangeable but oncogenetically equivalent events, and the nonrandomness of the chromosomal alterations underscores the preferential pathways involved in tumor initiation and progression.  相似文献   

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