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Additional Chromosome (additional + chromosome)
Selected AbstractsClear cell sarcoma of soft tissue: diagnostic utility of fluorescence in situ hybridization and reverse transcriptase polymerase chain reactionJOURNAL OF CUTANEOUS PATHOLOGY, Issue 4 2008Choladda V. Curry A 7-year-old girl presented with pain and progressive swelling on the left plantar surface. Biopsy of a 2.5 cm mass showed nests of large round to oval neoplastic cells with abundant amphophilic to clear cytoplasm, prominent nucleoli and high mitotic activity. Occasional cells showed spindled morphology. Infrequent melanin pigment was present. Melanocytic markers (HMB45, S-100) were diffusely positive. A diagnosis of clear cell sarcoma of soft tissue (CCSS) was made, and the mass was re-excised with negative margins. 28 months later, a 1.0 cm pulmonary nodule was identified and wedge excision showed metastatic CCSS. Cytogenetics showed a complex karyotype (unbalanced translocation der(12;14)(q10;q10), additional chromosome 22 material of unknown origin). Although the CCSS translocation t(12;22)(q13;q12) was not identified, EWSR1 gene rearrangement was detected by fluorescence in situ hybridization (FISH). Reverse transcription polymerase chain reaction (RT-PCR) showed an EWS-ATF1 fusion transcript, confirmed by direct sequencing. CCSS requires differentiation from malignant melanoma, because of overlapping clinical presentations, sites of involvement, histomorphology, immunocytochemical profiles and ultrastructure. In many circumstances, definitive diagnosis is only possible with confirmation of the CCSS-defining translocation. [source] Clear Cell Sarcoma of Soft Tissue with Cytogenetic and Molecular AnalysesJOURNAL OF CUTANEOUS PATHOLOGY, Issue 1 2006C. Vejabhuti A 7-year-old girl presented with pain and progressive swelling on the left plantar surface. Biopsy of a 2.5 cm mass demonstrated nests of large oval tumor cells with high nuclear-to-cytoplasm ratio, amphophilic to clear cytoplasm, prominent nucleoli, and brisk mitotic activity. Occasional cells showed spindled morphology. Infrequent melanin pigment was present. Melanocytic markers (HMB45, S-100) were diffusely positive. A diagnosis of clear cell sarcoma of soft tissue (CCSS) was made, and the tumor was re-excision with negative margins. 28 months later, a 1.0 cm pulmonary nodule was identified and showed CCSS. Cytogenetics demonstrated a complex karyotype (unbalanced translocation der(12;14)(p10;q10), additional chromosome 22 material of unknown origin). Although the CCSS translocation t(12;22)(q13;q12) was not identified, EWSR1 gene rearrangement was detected by fluorescence in situ hybridization (FISH). RT-PCR demonstrated an EWS-ATF1 fusion transcript, confirmed by direct sequencing. CCSS requires differentiation from malignant melanoma, due to overlapping clinical presentations, sites of involvement, histomorphology, immunocytochemical profiles, and ultrastructure. In many circumstances, definitive diagnosis is only possible with confirmation of the CCSS tumor-defining translocation. [source] Development of dominant nuclear male-sterile lines with a blue seed marker in durum and common wheatPLANT BREEDING, Issue 1 2001N. Tian Abstract In order to develop genie male-sterile lines with a blue seed marker, male-sterile plants, controlled by a dominant nuclear gene Ms2, were used as female parents against a 4E disomic addition line ,Xiaoyan Lanli'(2n= 44, AABBDD+4EII) as the male parent to produce monosomic addition lines with blue seed. Male-sterile plants from the monosomic addition lines were pollinated with durum wheat for several generations and in 1989 a male-sterile line with the blue grain gene and the male-sterile gene Ms2 on the same additional chromosome was detected and named line 89-2343. Using this line, the blue seed marker was successfully added to a short male-sterile line containing Ms2 and Rht10. The segregation ratios of male sterility and seed colour as well as the chromosome figurations of different plants indicated that the blue grain genes, Ms2 and Rht10 were located on the same additional chromosome. Cytological analysis showed that the blue marker male-sterile lines in durum wheat and common wheat were monosomic with an additional chromosome 4E. The inheritance ratio for blue seed male-sterile plants and white seed male-fertile plants was 19.7% and 80.3%, respectively, in common wheat. The potential for using blue marker sterile lines in population improvement and hybrid production is discussed. [source] Three different origins for apparent triploid/diploid mosaicsPRENATAL DIAGNOSIS, Issue 7 2003Art Daniel Abstract Four apparent triploid/diploid mosaic cases were studied. Three of the cases were detected at prenatal diagnosis and the other was of an intellectually handicapped, dysmorphic boy. Karyotypes were performed in multiple tissues if possible, and the inheritance of microsatellites was studied with DNA from fetal tissues and parental blood. Non-mosaic triploids have a different origin from these mosaics with simple digyny or diandry documented in many cases. Three different mechanisms of origin for these apparent mosaics were detected: (1) chimaerism with karyotypes from two separate zygotes developing into a single individual, (2) delayed digyny, by incorporation of a pronucleus from a second polar body into one embryonic blastomere, and (3) delayed dispermy, similarly, by incorporation of a second sperm pronucleus into one embryonic blastomere. In three of the four cases, there was segregation within the embryos of triploid and diploid cell lines into different tissues from which DNA could be isolated. In case 2 originating by digyny, the same sperm allele at each locus could be detected in both triploid and diploid tissues, which is supportive evidence for the involvement of a single sperm and for true mosaicism rather than chimaerism. Similarly, in case 4 originating by dispermy, the same single ovum allele at each locus could be detected in diploid and triploid tissues, confirming mosaicism. In the chimaeric case (case 3), the diploid line had the karyotype 47,XY,+16 while the triploid line was 69,XXY. This suggests a chimaera, since, in a true mosaic, the triploid line should also contain the additional chromosome 16. Supporting the interpretation of a chimaeric origin for this case, the DNA data showed that the triploidy was consistent with MII non-disjunction (i.e. involving a diploid ovum). In the mosaic cases (1, 2, 4), there was no evidence of the involvement of a diploid sperm or a diploid ova, and in triploid/diploid mosaicism, an origin from a diploid gamete is excluded, since all such conceptuses would be simple triploids. In one of these triploid/diploid mosaics detected at prenatal diagnosis by CVS, the triploid line seemed to be sequestered into the extra-fetal tissues (confined placental mosaicism). This fetus developed normally and a normal infant was born with no evidence of triploidy in newborn blood or cord blood at three months of age. Copyright © 2003 John Wiley & Sons, Ltd. [source] The chromosome 7q region association with rheumatoid arthritis in females in a british population is not replicated in a North American case,control seriesARTHRITIS & RHEUMATISM, Issue 1 2009Benjamin D. Korman Objective The single-nucleotide polymorphism (SNP) rs11761231 on chromosome 7q has been reported to be sexually dimorphic marker for rheumatoid arthritis (RA) susceptibility in a British population. We sought to replicate this finding and to better characterize susceptibility alleles in the region in a North American population. Methods DNA from 2 North American collections of RA patients and controls (1,605 cases and 2,640 controls) was genotyped for rs11761231 and 16 additional chromosome 7q tag SNPs using Sequenom iPlex assays. Association tests were performed for each collection and also separately, contrasting male cases with male controls and female cases with female controls. Principal components analysis (EigenStrat) was used to determine association with RA before and after adjusting for population stratification in the subset of the samples for which there were whole-genome SNP data (772 cases and 1,213 controls). Results We failed to replicate an association of the 7q region with RA. Initially, rs11761231 showed evidence for association with RA in the North American Rheumatoid Arthritis Consortium (NARAC) collection (P = 0.0073), and rs11765576 showed association with RA in both the NARAC (P = 0.038) and RA replication (P = 0.0013) collections. These markers also exhibited sex differentiation. However, in the whole-genome subset, neither SNP showed significant association with RA after correction for population stratification. Conclusion While 2 SNPs on chromosome 7q appeared to be associated with RA in a North American cohort, the significance of this finding did not withstand correction for population substructure. Our results emphasize the need to carefully account for population structure to avoid false-positive disease associations. [source] Evidence for a single-step mechanism in the origin of hyperdiploid childhood acute lymphoblastic leukemiaGENES, CHROMOSOMES AND CANCER, Issue 2 2005Kajsa Paulsson High hyperdiploidy (>50 chromosomes) in childhood acute lymphoblastic leukemia (ALL) is characterized by nonrandom multiple trisomies and tetrasomies involving in particular chromosomes X, 4, 6, 8, 10, 14, 17, 18, and 21. This characteristic karyotypic pattern, the most common in pediatric ALL, may arise via a tetraploid state with subsequent loss of chromosomes, by sequential gains of chromosomes in consecutive cell divisions, or by simultaneous gain of chromosomes in a single mitosis. These alternatives may be distinguished by investigation of the allelic ratios of loci on the tetrasomic and disomic chromosomes. Previous studies of tetrasomy 21 and of the occurrence of uniparental disomies (UPDs) have suggested that the most likely mechanism is simultaneous gain. However, the other pathways have not been definitely excluded because complete analyses of all disomies and tetrasomies have never been performed. In the present study, we investigated 27 hyperdiploid ALLs by using 58 polymorphic microsatellite markers mapped to 23 of the 24 human chromosomes. Twenty-six tetrasomies were analyzed (involving chromosomes X, 8, 10, 14, 18, and 21), and the frequency of UPDs was determined in 10 cases. In total, 200 chromosomes were studied. Equal allele dosage was observed in 24 of 26 tetrasomies, and only 7 UPDs were found. These data strongly suggest that hyperdiploidy in childhood ALL generally arises by a simultaneous gain of all additional chromosomes in a single abnormal mitosis. © 2005 Wiley-Liss, Inc. [source] FISH analysis of 15 chromosomes in human day 4 and 5 preimplantation embryos: the added value of extended aneuploidy detectionPRENATAL DIAGNOSIS, Issue 1 2007E. B. Baart Abstract Objective Screening for an increased number of chromosomes may improve the detection of abnormal embryos and thus contribute to the capability of preimplantation genetic screening (PGS) to detect the embryo(s) for transfer in IVF with the best chance for a healthy child. Good-quality day 4 and 5 embryos were analyzed after cryopreservation for the nine chromosomes mostly recommended for screening (13, 14, 15, 16, 18, 21, 22, X and Y), next to six additional chromosomes which are less well studied in this context (1, 2, 7, 6, 10 and 17). Method The copy numbers of 15 chromosomes were investigated by fluorescence in situ hybridization (FISH) in three consecutive rounds. The proportion of aneuploid and mosaic embryos was determined and compared in retrospect to results in case only the recommended probe set had been analyzed. Results A total of 52 embryos from 29 infertile women were analyzed. Screening the embryos for six additional chromosomes increased the proportion of abnormal embryos from 67 to 81% (P = 0.03), owing to an increase in mosaic embryos. Conclusion All but one of the meiotic aneuploidies found in this study would have been detected by the probe set most frequently used in PGS clinics. However, aneuploid cell lines originating from mitotic errors could be detected for almost all chromosomes, so screening of six additional chromosomes mainly increased the proportion of mosaic embryos. The added value of screening for six additional chromosomes in PGS for clinical practice will remain undetermined as long as the fate of mosaic embryos after transfer is unclear. Copyright © 2007 John Wiley & Sons, Ltd. [source] | |||||||||||||