OBJECTIVE: To explore the clinical and laboratory characteristics of hematological tumors with different types of abnormalities in platelet derived growth factor β (PDGFRβ) gene. METHODS: A retrospective analysis was carried out on 141 patients with abnormal long arm of chromosome 5 (5q) and comprehensive medical history data from Changhai Hospital Affiliated to Naval Medical University from 2009 to 2020, and their clinical data were collected. R-banding technique was used for chromosomal karyotyping analysis for the patient's bone marrow, and fluorescence in situ hybridization (FISH) was used to detect the PDGFRβ gene. The results of detection were divided into the amplification group, deletion group, and translocation group based on FISH signals. The three sets of data column crosstabs were statistically analyzed, and if the sample size was n >= 40 and the expected frequency T for each cell was >= 5, a Pearson test was used to compare the three groups of data. If N < 40 and any of the expected frequency T for each cell was < 5, a Fisher's exact test is used. Should there be a difference in the comparison results between the three sets of data, a Bonferroni method was further used to compare the data. RESULTS: In total 98 patients were detected to have PDGFRβ gene abnormalities with the PDGFRβ probe, which yielded a detection rate of 69.50% (98/141). Among these, 38 cases (38.78%) had PDGFRβ gene amplifications, 57 cases (58.16%) had deletions, and 3 (3.06%) had translocations. Among the 98 cases, 93 were found to have complex karyotypes, including 37 cases from the amplification group (97.37%, 37/38), 55 cases from the deletion group (96.49%, 55/57), and 1 case from the translocation group (33.33%, 1/3). Analysis of three sets of clinical data showed no significant gender preponderance in the groups (P > 0.05). The PDGFRβ deletion group was mainly associated with myeloid tumors, such as acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) (P < 0.001). The PDGFRβ amplification group was more common in lymphoid tumors, such as multiple myeloma (MM) (P < 0.001). The PDGFRβ translocation group was also more common in myelodysplastic/myeloproliferative tumors (MDS/MPN). CONCLUSION Tumors with PDGFRβ gene rearrangement may exhibit excessive proliferation of myeloproliferative tumors (MPN) and pathological hematopoietic changes in the MDS, and have typical clinical and hematological characteristics. As a relatively rare type of hematological tumor, in addition to previously described myeloid tumors such as MPN or MDS/MPN, it may also cover lymphoid/plasma cell tumors such as multiple myeloma and non-Hodgkin's lymphoma.
Humans ; Clinical Relevance ; Hematologic Neoplasms/genetics* ; In Situ Hybridization, Fluorescence ; Multiple Myeloma ; Myelodysplastic Syndromes ; Retrospective Studies ; Translocation, Genetic

OBJECTIVE: To carry out combined genetic analysis on two patients suspected for Burkitt lymphoma to facilitate their diagnosis and treatment. METHODS: G banded karyotyping and interphase and metaphase fluorescence in situ hybridization (FISH) were used to detect the specific sites of chromosomes by using separate and fusion probes. RESULTS: The separate probe showed no presence of MYC gene abnormality, while fusion probe confirmed the IGH::MYC translocation in the samples. Combined with the clinical features and pathological characteristics, the two patients were finally diagnosed with Burkitt lymphoma, which was confirmed by targeted capture next generation sequencing. CONCLUSION The separate probe for the MYC gene has some shortcomings and should be used together with dual fusion probe to improve the accuracy of diagnosis.
Humans ; Burkitt Lymphoma/pathology* ; In Situ Hybridization, Fluorescence ; Genes, myc ; Translocation, Genetic ; Karyotyping

OBJECTIVE: To retrospectively analyze the results of chromosomal microarray analysis (CMA) and parental origins of unbalanced translocations among 17 patients, so as to provide reference for their genetic counseling. METHODS: The results of CMA for 7 001 samples tested in Chengdu Women and Children's Central Hospital from January 2019 to January 2022 were retrospectively reviewed. Unbalanced reciprocal translocation was defined as two non-homologous chromosomes with lost and gained segments respectively or both with gained segments, and their parental origins were identified by parental chromosomal karyotyping and/or fluorescence in situ hybridization (FISH). RESULTS: In total 17 unbalanced translocations were identified. In three cases, two non-homologous chromosomes both had gained segments, which constituted a derivative chromosome, with the total number of chromosomes being 47. In the remaining 14 cases, there was a terminal deletion on one chromosome and a terminal duplication on the other, 10 of which were confirmed by karyotyping, with the total number of chromosomes being 46. In the derivative chromosome, the lost segment was replaced by a gained segment from another chromosome. Among 15 cases undergoing parental origin analysis, 12 had paternal or maternal chromosomal abnormalities, including 11 balanced translocations and 1 unbalanced translocation. The unbalanced gametes therefore may form through meiosis. In 3 cases, the parental chromosomes were normal, indicating a de novo origin. CONCLUSION Discovery of terminal duplication and deletion or gained segments on two non-homologous chromosomes by CMA is suggestive of parental balanced translocation, which can facilitate genetic counseling and assessment the recurrence risk for subsequent pregnancies.
Child ; Pregnancy ; Humans ; Female ; In Situ Hybridization, Fluorescence ; Retrospective Studies ; Translocation, Genetic ; Microarray Analysis ; Chromosomes

OBJECTIVE: To investigate the clinical and prognostic characteristics of primary acute myeloid leukemia (AML) with 11q23/KMT2A rearrangements. METHODS: Clinical data of 90 patients with primary AML and 11q23/KMT2A rearrangements were analyzed retrospectively. RESULTS: By karyotyping analysis, 80 of the 90 patients had translocations involving 11q23/KMT2A, with t(9;11)(p22;q23), t(6;11)(q27;q23), t(10;11)(p12;q23) and t(11;19)(q23;p13) being the most common ones, while 10 cases were found to have non-translocation abnormalities. The overall complete remission (CR) rate was 75.6%, and patients with t(6;11) had lower CR rate compared with non-t(6;11) patients (47.1% vs. 82.2%, P = 0.005). After a median follow-up of 24.5 months, the patients receiving allo-hematopoietic stem cell transplantation (allo-HSCT) had significantly higher 3-year overall survival (OS) (80.3% vs. 16.6%, P < 0.001) and 3-year event-free survival (EFS) (73.5% vs. 16.3%, P < 0.001) compared with non-transplant patients. Patients with t(6;11) had the lowest 3-year OS (11.8% vs. 56.0%, P < 0.001) and 3-year EFS (5.9% vs. 53.8%, P < 0.001) compared with other type of abnormalities. No significant difference was noted in the survival between patients with t(9;11) and non-t(9;11) regardless whether they had received HSCT. CONCLUSION The clinical characteristics of primary AML with 11q23/KMT2A rearrangements are heterogeneous. Patients did not receive HSCT had poorer survival, particularly with the presence of t(6;11). Allo-HSCT could significantly improve the survival of such patients.
Humans ; Retrospective Studies ; Leukemia, Myeloid, Acute/therapy* ; Translocation, Genetic ; Gene Rearrangement ; Prognosis

Brain development requires a delicate balance between self-renewal and differentiation in neural stem cells (NSC), which rely on the precise regulation of gene expression. Ten-eleven translocation 2 (TET2) modulates gene expression by the hydroxymethylation of 5-methylcytosine in DNA as an important epigenetic factor and participates in the neuronal differentiation. Yet, the regulation of TET2 in the process of neuronal differentiation remains unknown. Here, the protein level of TET2 was reduced by the ubiquitin-proteasome pathway during NSC differentiation, in contrast to mRNA level. We identified that TET2 physically interacts with the core subunits of the glucose-induced degradation-deficient (GID) ubiquitin ligase complex, an evolutionarily conserved ubiquitin ligase complex and is ubiquitinated by itself. The protein levels of GID complex subunits increased reciprocally with TET2 level upon NSC differentiation. The silencing of the core subunits of the GID complex, including WDR26 and ARMC8, attenuated the ubiquitination and degradation of TET2, increased the global 5-hydroxymethylcytosine levels, and promoted the differentiation of the NSC. TET2 level increased in the brain of the Wdr26^+/- mice. Our results illustrated that the GID complex negatively regulates TET2 protein stability, further modulates NSC differentiation, and represents a novel regulatory mechanism involved in brain development.
Animals ; Mice ; DNA-Binding Proteins/genetics* ; Cell Differentiation ; Neural Stem Cells ; Translocation, Genetic ; Ubiquitins/genetics* ; Ligases/genetics*

Humans ; Multiple Myeloma/genetics* ; Karyotyping ; Translocation, Genetic/genetics*

OBJECTIVE: To explore the genetic characteristics of a fetus with a high risk by maternal serum screening during the second trimester. METHODS: Genetic counseling was provided to the pregnant woman on March 22, 2020 at Henan Provincial People's Hospital. G-banded chromosomal karyotyping and array comparative genomic hybridization (aCGH) were carried out on the amniotic fluid sample and peripheral blood samples from the couple. RESULTS: The fetus and the pregnant woman were respectively found to have a 46,XX,der(6)t(6;14)(q27;q31.2) and 46,XX,t(6;14)(q27;q31.2) karyotype, whilst the husband was found to have a normal karyotype. aCGH analysis has identified a 6.64 Mb deletion at 6q26q27 and a 19.98 Mb duplication at 14q31.3q32.33 in the fetus, both of which were predicted to be pathogenic copy number variations. No copy number variation was found in the couple. CONCLUSION The unbalanced chromosome abnormalities in the fetus have probably derived from the balanced translocation carried by the pregnant woman. aCGH can help to determine the types of fetal chromosome abnormalities and site of chromosomal breakage, which may facilitate the prediction of fetal outcome and choice for subsequent pregnancies.
Pregnancy ; Female ; Humans ; Comparative Genomic Hybridization ; DNA Copy Number Variations ; Translocation, Genetic ; Chromosome Aberrations ; Fetus ; Prenatal Diagnosis

OBJECTIVE: To explore the genetic basis for a rare case of acute B-lymphocytic leukemia (B-ALL) with double Philadelphia chromosomes (Ph) and double derivative chromosome 9s [der(9)]. METHODS: A patient with double Ph and double der(9) B-ALL who presented at Shanghai Zhaxin Intergrated Traditional Chinese and Western Medicine Hospital in June 2020 was selected as the subject. Bone marrow morphology, flow cytometry, G-banding karyotyping, fluorescence in situ hybridization (FISH), genetic testing and chromosomal microarray analysis (CMA) were used to analyze bone marrow samples from the patient at various stages. RESULTS: At initial diagnosis, the patient's bone marrow morphology and flow immunotyping have both supported the diagnosis of B-ALL. G-banded karyotyping of the patient indicated double Ph, in addition with hyperdiploid chromosomes involving translocations between chromosomes 9 and 22. BCR-ABL1 fusion gene was positive. Genetic testing at the time of recurrence revealed presence of a heterozyous c.944C>T variant in the kinase region of the ABL1 gene. FISH showed a signal for ABL1-BCR fusion on both chromosome 9s. CMA showed that the mosaicism homozygosity ratio of chromosome 9 was about 40%, and the mosaicism duplication ratio of chromosome 22 was about 43%. CONCLUSION Since both der(9) homologs were seen in 40% of cells, the possible mechanism for the double der(9) in this patient may be similar to that of double Ph, which might have resulted from non-disjunction during mitosis in the Ph chromosome-positive cell clone.
Humans ; Philadelphia Chromosome ; In Situ Hybridization, Fluorescence/methods* ; China ; Chromosome Aberrations ; Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics* ; Translocation, Genetic ; Fusion Proteins, bcr-abl/genetics* ; Chromosomes, Human, Pair 9/genetics*

Large-scale genetic manipulation of the genome refers to the genetic modification of large fragments of DNA using knockout, integration and translocation. Compared to small-scale gene editing, large-scale genetic manipulation of the genome allows for the simultaneous modification of more genetic information, which is important for understanding the complex mechanisms such as multigene interactions. At the same time, large-scale genetic manipulation of the genome allows for larger-scale design and reconstruction of the genome, and even the creation of entirely new genomes, with great potential in reconstructing complex functions. Yeast is an important eukaryotic model organism that is widely used because of its safety and easiness of manipulation. This paper systematically summarizes the toolkit for large-scale genetic manipulation of the yeast genome, including recombinase-mediated large-scale manipulation, nuclease-mediated large-scale manipulation, de novo synthesis of large DNA fragments and other large-scale manipulation tools, and introduces their basic working principles and typical application cases. Finally, the challenges and developments in large-scale genetic manipulation are presented.
DNA ; Gene Editing ; Genetic Engineering ; Saccharomyces cerevisiae/genetics* ; Translocation, Genetic

OBJECTIVE: To carry out prenatal genetic testing for a fetus with de novo 46,X,der(X)t(X;Y)(q26;q11). METHODS: A pregnant woman who had visited the Birth Health Clinic of Lianyungang Maternal and Child Health Care Hospital on May 22, 2021 was selected as the study subject. Clinical data of the woman was collected. Peripheral blood samples of the woman and her husband and umbilical cord blood of the fetus were collected and subjected to conventional G-banded chromosomal karyotyping analysis. Fetal DNA was also extracted from amniotic fluid sample and subjected to chromosomal microarray analysis (CMA). RESULTS: For the pregnant women, ultrasonography at 25th gestational week had revealed permanent left superior vena cava and mild mitral and tricuspid regurgitation. G-banded karyotyping analysis showed that the pter-q11 segment of the fetal Y chromosome was connected to the Xq26 of the X chromosome, suggesting a Xq-Yq reciprocal translocation. No obvious chromosomal abnormality was found in the pregnant woman and her husband. The CMA results showed that there was approximately 21 Mb loss of heterozygosity at the end of the long arm of the fetal X chromosome [arr [hg19] Xq26.3q28(133912218_154941869)×1], and 42 Mb duplication at the end of the long arm of the Y chromosome [arr [hg19] Yq11.221qter(17405918_59032809)×1]. Combined with the search results of DGV, OMIM, DECIPHER, ClinGen and PubMed databases, and based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the deletion of arr[hg19] Xq26.3q28(133912218_154941869)×1 region was rated as pathogenic, and the duplication of arr[hg19] Yq11.221qter(17405918_59032809)×1 region was rated as variant of uncertain significance. CONCLUSION The Xq-Yq reciprocal translocation probably underlay the ultrasonographic anomalies in this fetus, and may lead to premature ovarian insufficiency and developmental delay after birth. Combined G-banded karyotyping analysis and CMA can determine the type and origin of fetal chromosomal structural abnormalities as well as distinguish balanced and unbalanced translocations, which has important reference value for the ongoing pregnancy.
Humans ; Child ; Pregnancy ; Female ; Vena Cava, Superior ; In Situ Hybridization, Fluorescence ; Chromosome Aberrations ; Karyotyping ; Translocation, Genetic ; Fetus ; Prenatal Diagnosis/methods*