scholarly journals A novel phenotype of 13q12.3 microdeletion characterized by epilepsy in an Asian child: a case report

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Mina Wang ◽  
Bin Li ◽  
Zehuan Liao ◽  
Yu Jia ◽  
Yuanbo Fu
Keyword(s):  
De Novo ◽  
Snp Array ◽  
Epileptic Seizures ◽  
Slow Waves ◽  
Recessive Mutation ◽  
Array Analysis ◽  
Single Nucleotide ◽  
Case Presentation ◽  
Snp Array Analysis ◽  
Cytogenetic Band

Abstract Background The microdeletion of chromosome 13 has been rarely reported. Here, we report a 14-year old Asian female with a de novo microdeletion on 13q12.3. Case presentation The child suffered mainly from two types of epileptic seizures: partial onset seizures and myoclonic seizures, accompanied with intellectual disability, developmental delay and minor dysmorphic features. The electroencephalogram disclosed slow waves in bilateral temporal, together with generalized spike-and-slow waves, multiple-spike-and-slow waves and slow waves in bilateral occipitotemporal regions. The exome sequencing showed no pathogenic genetic variation in the patient’s DNA sample. While the single nucleotide polymorphism (SNP) array analysis revealed a de novo microdeletion spanning 2.324 Mb, within the cytogenetic band 13q12.3. Conclusions The epilepsy may be associated with the mutation of KATNAL1 gene or the deletion unmasking a recessive mutation on the other allele, and our findings could provide a phenotypic expansion.

scholarly journals SNP array analysis in hematologic malignancies: avoiding false discoveries

Blood ◽  
2010 ◽  
Vol 115 (21) ◽  
pp. 4157-4161 ◽  
Author(s):  
Stefan Heinrichs ◽  
Cheng Li ◽  
A. Thomas Look
Keyword(s):  
Single Nucleotide Polymorphism ◽  
High Resolution ◽  
Snp Array ◽  
Hematologic Malignancies ◽  
Cancer Genome ◽  
Patient Specific ◽  
Nucleotide Polymorphism ◽  
Array Analysis ◽  
Single Nucleotide ◽  
Therapeutic Decisions

Comprehensive analysis of the cancer genome has become a standard approach to identifying new disease loci, and ultimately will guide therapeutic decisions. A key technology in this effort, single nucleotide polymorphism arrays, has been applied in hematologic malignancies to detect deletions, amplifications, and loss of heterozygosity (LOH) at high resolution. An inherent challenge of such studies lies in correctly distinguishing somatically acquired, cancer-specific lesions from patient-specific inherited copy number variations or segments of homozygosity. Failure to include appropriate normal DNA reference samples for each patient in retrospective or prospective studies makes it difficult to identify small somatic deletions not evident by standard cytogenetic analysis. In addition, the lack of proper controls can also lead to vastly overestimated frequencies of LOH without accompanying loss of DNA copies, so-called copy-neutral LOH. Here we use examples from patients with myeloid malignancies to demonstrate the superiority of matched tumor and normal DNA samples (paired studies) over multiple unpaired samples with respect to reducing false discovery rates in high-resolution single nucleotide polymorphism array analysis. Comparisons between matched tumor and normal samples will continue to be critical as the field moves from high resolution array analysis to deep sequencing to detect abnormalities in the cancer genome.

scholarly journals CBFA2T3-GLIS2 Fusion Gene Cause Dismal Clinical Course in Acute Megakaryocytic Leukemia of Down Syndrome

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 5184-5184
Author(s):  
Nao Takasugi ◽  
Kenichi Amano ◽  
Yasuo Kubota ◽  
Shota Kato ◽  
Yuichi Mitani ◽  
...  
Keyword(s):  
Down Syndrome ◽  
Mutational Analysis ◽  
Clinical Course ◽  
Fusion Gene ◽  
Snp Array ◽  
Genomic Analysis ◽  
Array Analysis ◽  
Snp Array Analysis ◽  
Acute Megakaryocytic Leukemia ◽  
Gata1 Mutation

[Introduction] Acute megakaryocytic leukemia of Down syndrome (DS-AMKL) is characterized by excellent outcome with chemotherapy in contrast to non-Down syndrome-related AMKL (non-DS-AMKL). DS-AMKL and non-DS-AMKL have distinct genetic features which may underlie their different clinical characteristics. DS-AMKL is initiated by a GATA1 mutation in the transient abnormal myelopoiesis (TAM) phase and developed with further mutations of other regulators, while non-DS-AMKL is a heterogeneous group which occasionally carry chimeric oncogenes. CBFA2T3-GLIS2 fusion gene is identified in about 30% of children with non-DS-AMKL, and reported as a strong poor prognostic factor in pediatric AMKL. However, CBFA2T3-GLIS2 has never been reported in DS-AMKL and adult AMKL patients. We performed genomic analysis of DS-AMKL including atypical case with difficult clinical course. This is the first report of DS-AMKL harboring the CBFA2T3-GLIS2 fusion gene. [Case] The patient is a 1-year-old female of DS-AMKL with no prior episode of TAM. G-banding analysis revealed the karyotype both of the leukemic cells and normal tissue sample; 47, XX, +21. Chimeric genes of AML1-MTG8, CBFB-MYH, DEK-CAN, MLL-LTG4, MLL-LTG9, MLL-ENL and abnormalities of KIT and FLT3 were not detected. The chemotherapy according to the Japanese Pediatric Leukemia / Lymphoma Study Group AML-D05 protocol, gemtuzumab ozogamicin, IDA-FLAG regimen (idarubicin, fludarabine, cytarabine, filgrastim) and clofarabine-based regimen were tried, but all of them failed to achieve complete remission (CR). She underwent umbilical cord blood transplantation and relapsed on day 35 after transplantation. Once she showed a response to azacitidine, but finally she died on day 293 after transplantation. [Materials and Methods] We performed whole transcriptome sequencing (RNAseq), SNP array analysis, mutational analysis of GATA1 in 6 DS-AMKL samples, which included this refractory sample and five DS-AMKL samples with GATA1 mutations. To analyze gene expression profiling, we applied the hierarchical clustering method and principal component analysis. [Results] RNA sequencing analysis identified a fusion gene involving exon 10 of CBFA2T3 and exon 2 of GLIS2 gene in this refractory sample. This fusion gene was a result of a cryptic inversion on chromosome 16 and the in-frame fusion of both genes. The fusion transcript was validated by reverse transcription-polymerase chain reaction (RT-PCR) followed by Sanger sequencing. Though SNP array analysis confirmed 21 trisomy, it did not identify other copy number aberrations. PCR analysis did not detect GATA1 mutation in this refractory sample, which can be identified in other DS-AMKL samples. Expression analysis elucidated DS-AMKL with CBFA2T3-GLIS2 fusion had distinct expression profile from DS-AMKL with GATA1 mutations. [Discussion] CBFA2T3-GLIS2 fusion is the most common chimeric oncogene identified in non-DS-AMKL children, but has never been detected in DS-AMKL patients. Patients with non-DS-AMKL, especially holding CBFA2T3-GLIS2 fusion gene, have poorer outcomes than DS-AMKL. DS-AMKL patients generally have GATA1 mutations, show high sensitivity to chemotherapy, and can be treated with less intensive chemotherapy. However, our case had no GATA1 mutation and could not achieve CR despite intensive chemotherapy and transplantation. Thus, it is suggested this fusion gene caused the resistance to chemotherapies including hematopoietic stem cell transplantation in our case. Therefore, our case suggests patients with DS-AMKL should be surveyed genomic investigations including RNAseq and mutational analysis of GATA1 to identify their molecular biological subtypes before treatments are initiated. In case that fusion genes are detected in DS-AMKL patients, they must undergo highly intense chemotherapies, looking ahead to transplantation from the beginning of the treatment. Moreover, in case of harboring CBFA2T3-GLIS2 fusion gene, some potential therapies have been proposed, so that efficacy of such new therapies should be validated in a cell line-derived xenograft or patient-derived xenograft model. [Conclusion] DS-AMKL is generally known to show superior outcome, but DS-AMKL without GATA1 mutation and with CBFA2T3-GLIS2 fusion gene shows resistance to chemotherapies. For DS-AMKL patients, it is desirable to perform genomic analysis including RNAseq before chemotherapy. Disclosures No relevant conflicts of interest to declare.

scholarly journals SNP Array Analysis Reveals Novel Genomic Abnormalities Including Copy Neutral Loss of Heterozygosity in Anaplastic Oligodendrogliomas

PLoS ONE ◽  
2012 ◽  
Vol 7 (10) ◽  
pp. e45950 ◽  
Author(s):  
Ahmed Idbaih ◽  
François Ducray ◽  
Caroline Dehais ◽  
Célia Courdy ◽  
Catherine Carpentier ◽  
...  
Keyword(s):  
Loss Of Heterozygosity ◽  
Neutral Loss ◽  
Snp Array ◽  
Array Analysis ◽  
Snp Array Analysis

scholarly journals A Private 16q24.2q24.3 Microduplication in a Boy with Intellectual Disability, Speech Delay and Mild Dysmorphic Features

Genes ◽  
2020 ◽  
Vol 11 (6) ◽  
pp. 707 ◽  
Author(s):  
Orazio Palumbo ◽  
Pietro Palumbo ◽  
Ester Di Muro ◽  
Luigia Cinque ◽  
Antonio Petracca ◽  
...  
Keyword(s):  
Intellectual Disability ◽  
De Novo ◽  
Chromosome Region ◽  
Snp Array ◽  
Supporting Evidence ◽  
Speech Delay ◽  
Dysmorphic Features ◽  
Phenotype Comparison ◽  
Molecular Comparison ◽  
Snp Array Analysis

No data on interstitial microduplications of the 16q24.2q24.3 chromosome region are available in the medical literature and remain extraordinarily rare in public databases. Here, we describe a boy with a de novo 16q24.2q24.3 microduplication at the Single Nucleotide Polymorphism (SNP)-array analysis spanning ~2.2 Mb and encompassing 38 genes. The patient showed mild-to-moderate intellectual disability, speech delay and mild dysmorphic features. In DECIPHER, we found six individuals carrying a “pure” overlapping microduplication. Although available data are very limited, genomic and phenotype comparison of our and previously annotated patients suggested a potential clinical relevance for 16q24.2q24.3 microduplication with a variable and not (yet) recognizable phenotype predominantly affecting cognition. Comparing the cytogenomic data of available individuals allowed us to delineate the smallest region of overlap involving 14 genes. Accordingly, we propose ANKRD11, CDH15, and CTU2 as candidate genes for explaining the related neurodevelopmental manifestations shared by these patients. To the best of our knowledge, this is the first time that a clinical and molecular comparison among patients with overlapping 16q24.2q24.3 microduplication has been done. This study broadens our knowledge of the phenotypic consequences of 16q24.2q24.3 microduplication, providing supporting evidence of an emerging syndrome.

SNP Array Analysis Reveals Copy Number Alterations and Uniparental Disomy in Mantle Cell Lymphomas at High Resolution.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 1585-1585
Author(s):  
Elena M. Hartmann ◽  
Itziar Salaverria ◽  
Silvia Bea ◽  
Andreas Zettl ◽  
Pedro Jares ◽  
...  
Keyword(s):  
High Resolution ◽  
Cell Lines ◽  
Copy Number ◽  
Snp Array ◽  
Uniparental Disomy ◽  
Genetic Alterations ◽  
Array Analysis ◽  
Snp Array Analysis ◽  
Copy Number Changes ◽  
500K Array

Abstract Mantle Cell Lymphoma (MCL) is an aggressive B-Cell Non Hodgkin Lymphoma which is genetically characterized by the translocation t(11;14). This translocation leads to juxtaposition of the Cyclin D1 gene and the IgH locus, resulting in constitutive overexpression of Cyclin D1 and consecutive cell cycle dysregulation. Apart from this typical structural genetic alteration, several studies using conventional or array-based comparative genomic hybridization (CGH) reported a high number of secondary numerical genetic alterations contributing to MCL lymphomagenesis and influencing the clinical behavior. Increasingly, there is evidence that loss of heterozygosity (LOH) without copy number changes (e.g. caused by mitotic recombination between the chromosomal homologues, also referred to as acquired (partial) uniparental disomy (a(p)UPD), is an important alternative mechanism for tumor suppressor gene inactivation. However, this phenomenon is undetectable by CGH techniques. Single Nucleotide Polymorphism (SNP) based arrays allow - in addition to high resolution copy number (CN) analyses and SNP genotyping - in the same experiment the analysis of loss of heterozygosity (LOH) events and hereby enable the detection of copy neutral LOH. We analyzed the 3 t(11;14)-positive MCL cell lines Granta 519, HBL-2 and JVM-2 and 5 primary tumor specimens from untreated MCL patients with both the Affymetrix GeneChip®Human Mapping 100K and 500K array sets. In the 3 cell lines, we found an excellent agreement between the copy number changes obtained by SNP array analysis and previously published array CGH results. Extending published results (Nielaender et al., Leukemia 2006), we found regions of pUPD in all 3 MCL cell lines, which often affected regions reported as commonly deleted in MCL. Intriguingly, HBL-2 that is characterized by relatively few chromosomal losses, carries an increased number of large regions showing copy neutral LOH. Furthermore, we compared the results obtained by the 100K and 500K mapping array sets from 5 primary MCL tumor specimens with previously published conventional CGH data. All cases showed genetic alterations in both conventional CGH and SNP array analysis. The total number of copy number alterations detected by conventional CGH was 35, including 23 losses, 10 gains and 2 amplifications. The total number of CN alterations detected by the mapping 100K and 500K array sets was 81 (50 losses, 26 gains and 5 amplifications) and 82 (50 losses, 27 gains and 5 amplifications), respectively. We found an excellent agreement in the large CN alterations detected by conventional CGH and both SNP array platforms. Furthermore, we identified >40 mostly small CN alterations that have not been detected by conventional CGH (median size <5MB for losses and <3Mb for gains). The CN alterations detected by the 100k and the 500K array sets were highly identical. Importantly, we discovered regions of partial UPD in 4 of the 5 MCL cases (size range from around 2Mb up to a single region >40Mb). In conclusion, the results demonstrate the capability of SNP array analysis for identifying CN alterations and partial UPD at high resolution in MCL cell lines as well as in primary tumor samples.

Genome-Wide DNA Copy Number Analysis by SNP Arrays of B-Cell Chronic Lymphocytic Leukemia: Correlation with Known Biological and Molecular Prognostic Markers.

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 1061-1061
Author(s):  
Laura Mosca ◽  
Sonia Fabris ◽  
Giovanna Cutrona ◽  
Luca Agnelli ◽  
Serena Matis ◽  
...  
Keyword(s):  
High Resolution ◽  
Copy Number ◽  
Prognostic Markers ◽  
Snp Array ◽  
Lymphocytic Leukemia ◽  
Array Analysis ◽  
Genome Wide ◽  
Trisomy 12 ◽  
Snp Array Analysis ◽  
Cell Chronic Lymphocytic Leukemia

Abstract B-cell chronic lymphocytic leukemia (B-CLL) is a genetically heterogeneous disease with a variable clinical course. Chromosomal changes have been identified by FISH in approximately 80% of patients, and the presence of specific lesions, such as trisomy 12 and 13q14, 11q23, 17p13.1 and 6q23 deletions represent prognostic markers for disease progression and survival. In order to characterize further the complexity of B-CLL genomic lesions, we performed high density, single nucleotide polymorphism (SNP) array analysis in highly purified neoplastic cells (>92%) from a panel of 100 untreated, newly diagnosed patients (57 males and 43 females; age, median 63 years, range 30–87) in Binet stage A. All patients were investigated by FISH for the presence of trisomy 12 (21 cases); 13q14 deletion (44 cases, 34 as the sole abnormality); 11q22.3, 17p13.1 and 6q23 (15, 7 and 2 patients, respectively). In addition, ZAP-70 and CD38 expression resulted positive in 42 and 46 patients, whereas IgVH genes were mutated in 45 patients. Genome-wide DNA profiling data were generated on GeneChip® Human Mapping 250K NspI arrays (Affymetrix); copy number alterations (CNA) were calculated using the DNA copy Bioconductor package, which looks for optimal breakpoints using circular binary segmentation (CBS) (Olshen et al, 2004). A total of 782 CNAs (ranging from 1 to 31 per sample, mean and median values 7.82 and 7, respectively) were detected; DNA losses (365/782=46.67% loss; 194/782=24.81% biallelic deletion) were found to be more frequent than gains (148/782=18.93% gain; 75/782=9.59% amplification). The most recurrent alterations detected by FISH were all confirmed by SNP array analysis, strengthening further the good reliability of such high-resolution technology. We identified 12 minimally altered regions (MARs) larger than 100 kb with a frequency higher than 5%. Among well known alterations, the largest was represented by chromosome 12 trisomy, followed by 6q, 17p and 11q23 deletions (32.87, 19.09 and 10.43 Mb, respectively) and 13q14 deletion (635 kb). Gain of 2p25.3 involves a common region of 4.39 Mb region in 7 patients, although it was extended to the whole short arm of chromosome 2 in 3 cases. Among those alterations previously described in B-CLL, we found losses at 14q32.33 (12 pts) and 22q11.2 (5 pts) involving the IGH and IGLλ loci, respectively. With regard to novel regions, we identified losses at 4q35.2 (5 pts) and 11q25 (6 pts). In addition we found a high frequency of losses/gains at 14q11.2 (42 pts) and 15q11.2 (33 pts), two genomic regions reported to be affected by DNA copy number variations in normal individuals. As regards correlations between CNAs and biological markers, we found that the number of CNAs is significantly higher in cases with unmutated IgVH (9.4; range 2–31) as compared with mutated IgVH (6; range 1–13) (p=0.002), while neither CD38 nor ZAP-70 expression showed significant correlation. In addition, a significant higher number of either CNAs (p=0.001), total MARs (p<0.0001) or even only novel MARs (p=0.009) was significantly associated with cases with 17p deletion or multiple cytogenetic aberrations as evaluated by FISH analysis. Our data indicate that genetic abnormalities involving chromosomal gains and losses are very common in early-stage B-CLL and further support the application of high resolution SNP array platforms in the characterization of genetic changes in the disease. In addition, we detected novel altered chromosomal regions that warrant further investigations to better define their pathogenetic and prognostic role in B-CLL.

Sign in / Sign up

Export Citation Format

Share Document