Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Monosomy”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 253 records · Page 14Linked to original sources

A natural history of a child with monosomy 5p syndrome (Cat-cry/Cri-du-chat syndrome) during the 18 years of follow-up.

A record of a natural history of a long-term case study devoted to monosomy 5p (Cat-cry/Cri-du-chat) syndrome has been described rarely. Knowledge on the range of the changes in phenotype attributable to advancing age can be useful in clinical diagnosis of monosomy 5p at the different developmental stages, including adolescence, as well in prognosis for genetic counseling. In this case a detailed analysis of the morphologic phenotype in a girl with del(5)(p13.3) observed from 4 months to 18 years of age is reported. The comparative analysis of the girl's phenotype in different developmental stages has revealed that microcephaly, flat occipital region, face asymmetry, wide spaced palpebral fissures, epicanthic folds, small mouth fissure, thin mucous lip, small and low set ears and short IV metacarpals has not changed with advancing age. However, facial asymmetry was more evident, frontal tubers were less prominent, nasal root and back became prominent nasal back became elongated, the subnasal region was shorter and marked malocclusion appeared.

Child↗

Monosomy 7 and unbalanced t(1;7) in an adolescent boy with myelodysplastic syndrome.

Monosomy 7 occurs in approximately 5% of cases of myelodysplastic syndrome (MDS) in children and is associated with a poor prognosis. The unbalanced translocation t(1;7) is common in therapy-related MDS in adults but is extremely rare in children, with only three cases reported to date. We describe a pediatric case of MDS with the unusual combination of monosomy 7 and unbalanced t(1;7) in two distinct clones. Both clones were detected at diagnosis and have persisted throughout the course of MDS in this patient, a 16-year-old boy without prior exposure to known mutagens. Because of recurrent severe infections associated with neutropenia, he was treated with recombinant human granulocyte-macrophage colony-stimulating factor. This therapy improved the neutrophil count but did not alter the karyotype or the progression of disease.

Adolescent↗

Monosomy 7, leukaemia and immunoglobulin heavy chain gene rearrangement.

We describe the haematological findings and clinical course of a 15-year-old male who presented with a spontaneous acute lymphoblastic leukaemia. The lymphoid origin of the leukaemia was supported by cell surface antigen studies and immunoglobulin heavy chain gene analysis. Bone marrow karyotype was simple monosomy 7 and the lymphoblasts expressing the myeloid associated antigen CD 33. Both of these features have been previously shown to indicate a poor prognosis. The findings in this patient support a previous hypothesis that monosomy 7 can arise at the stem cell level.

Adolescent↗

Monosomy-7 in childhood hemopoietic disorders.

Acquired pure monosomy-7 is associated with various myeloproliferative disorders (MPD), myelodysplasias (MDS), and acute myeloblastic leukemias (AML) in children and a poor prognosis. A series of 14 malignant blood disorders with pure monosomy-7 in children (eight MPD, two refractory anemia with excess of blasts, (RAEB), and four AML) is reported and compared with cases in the literature. The median age is significantly different in the patients with MPD and those with MDS or AML: 23, 80.5, and 112 months, respectively. The outcomes of MPD and RAEB are characterized by a high risk of rapid blastic transformation and resistance to polychemotherapy. Bone marrow transplantation (BMT) seems to be the best treatment, and one survival of two years in complete remission after autologous BMT in a child with AML is reported. Several myeloid cell lineages are involved in the proliferation, which partly explains the difficulties of cytologic classification and suggests that a pluripotent stem-cell is at the origin of the disease.

Adolescent↗

Application of DNA-DNA hybridization of dual labeled probes to the detection of trisomy 21, monosomy 21, and sex determination.

Chromosomal aneuploidy is usually identified by cytogenetic methods. However, for some purposes it would be desirable to have an easier method of recognizing specific trisomies or monosomies. We have devised such an assay. It involves the simultaneous hybridization of two chromosome-specific DNA probes labeled with different isotopes (32P and 35S) to human chromosomal DNA immobilized on a nitrocellulose filter. The hybridization signals are then counted, and the dpm ratios between the two isotopes are determined. In this paper we show the application of this technique in sex determination, in the analysis of two human cell lines reported to have chromosome 21 monosomy, and, especially, in testing for Down syndrome.

Cell Line↗

[Bone marrow monosomy 7 in children].

Three new cases of monosomy 7 are described. Two children, before onset of overt leukemia, had a preleukemic state: one with thrombopathy and myelodysplastic syndrome, the other with a moderate splenomegaly and an absolute monocytosis. In these two cases the leukemia was chemoresistant. The last child had a subacute myelomonocytic syndrome (juvenile type of chronic myelogenous leukemia) without high fetal hemoglobin value. She died from cachexia. The poor prognosis of monosomy 7 is underlined and such a chromosome deletion should be searched in myeloproliferative syndrome with monocytosis.

Blood Cell Count↗

Morphological characteristics of monosomy X in spontaneous abortions.

From a morphologic and cytogenetic study of 160 spontaneous abortion specimens with 45,X, as well as data from the literature, we conclude that monosomy X has characteristics which can suggest the diagnosis in prenatal life in the absence of a karyotype. Specimens in our study could be classified into four groups: (I) 49% consisted of a chorionic and amniotic sac, usually ruptured, containing a well-defined umbilical cord with a fragment of embryonic tissue at its end. (II) 25% consisted of small macerated embryos of 40-44 days developmental age, with pronounced retrognathia and lack of nasofrontal angle. Two specimens had a neural tube defect, one had cleft lip and palate, and two had an isolated cleft palate. The developmental age of the embryos was 5-6 weeks behind their gestational age. (III) 5% were very macerated second trimester fetuses with cystic hygromata, lymph-edema of the hands and feet, ascites, hydrothorax, and hypoplastic lungs. Four had coarctation of the aorta, three had single umbilical artery, and two had persistent left cardinal vein. Horseshoe kidney, ventricular septal defect, and anomalous subclavian artery were found once. (IV) The remaining 21% consisted only of fragments of ruptured sacs without an umbilical cord insertion site, pieces of fetal membranes or chorionic villi only. The spectrum of anomalies observed suggests that the pathogenetic mechanism for early death in 45,X embryos and fetuses may be related to vascular abnormalities or to abnormal fluid balance, leading to disturbed embryo-placental circulation, and excess fluid volume in the fetus. The 45,X karyotype is compatible with quite normal morphological development up to the fetal stage, and no specimens were found where development had ceased at a very early stage. The usual lethality of monosomy X may be explained by the presence of genes, essential for survival, on the pseudoautosomal segment of the X and Y. Lethality could result from recessive lethal mutations in this region, or from the necessity for two copies of this regions for normal development.

Abortion, Spontaneous↗

Dissociation of tdic chromosomes: about a t(15;18)(p11;p11) leading to 18p monosomy.

A 10-month-old girl with monosomy due to a de novo 45,XX,-15,-18,+tdic(15;18)(p11;p11) karyotype is described. The abnormal chromosome underwent dissociation into two telocentrics in 5/200 (2.5%) metaphases. This and other comparable instances indicate that, in addition to criss-cross separation of the dicentric chromatids, the characteristics of the anomalous reunion also influence the rate of dissociation. Besides, the mean maternal (31.2) and paternal (35.1) ages in this subtype of 18p monosomy are significantly increased.

Chromosome Banding↗

Childhood monosomy 7 syndrome: clinical and in vitro studies.

The clinical and cell growth characteristics of 11 children with monosomy 7 presenting as preleukemia (eight cases) or acute nonlymphoblastic leukemia (three cases) were studied. Anemia was common to all patients, with nine showing leukocytosis, seven thrombocytopenia, and one thrombocytosis. There was a striking predominance of males (M/F ratio, 10:1) and a young median age (3 years). Preleukemia evolved to acute nonlymphoblastic leukemia in five patients and to myelofibrosis in one. In vitro studies of bone marrow progenitor cells cultured in leukocyte feeder-stimulated agar revealed abnormal cell proliferative patterns, most often an increased number of small clusters, for all 11 subjects. The cells of some preleukemic patients showed increased growth even in the absence of an exogenous source of colony-stimulating factor, suggesting autonomous growth or possibly autocrine stimulation. Combination chemotherapy or bone marrow transplantation failed to induce complete remission in the seven patients who were treated. Our findings in these 11 cases confirm the poor prognosis of monosomy 7 presenting as preleukemia in children. The in vitro studies suggest an association between altered cell growth in vitro and clinical evolution to frank leukemia.

Acute Disease↗

Partial monosomy 10p syndrome.

A newborn infant with monosomy 10p13 is reported. The clinical signs and symptoms of the present case are compared with those of previously described cases. Although there is no pathognomonic feature, a characteristic monosomy 10p syndrome is recognizable.

Abnormalities, Multiple↗

Association of rat p15INK4B/p16INK4 deletions with monosomy 5 in kidney epithelial cell lines but not primary renal tumors.

Recently the putative tumor suppressor gene p16INK4 was mapped to human chromosome 9p21, which is homologous to rat chromosome 5. Monosomy of rat chromosome 5 occurs with high frequency in rat kidney tumor-derived cell lines (ERC lines). Thus, we studied these lines in order to investigate the involvement of p15INK4B and p16INK4 in the genesis of this tumor type. p15INK4B and p16INK4 were found by Southern blot analysis to be codeleted in five of seven of these lines. This was confirmed by Northern blot analysis with a probe for the rat p15INK4B gene. In normal rat tissues, expression of p15INK4B was abundant in lung (2.5 and 2.0 kilobases), less abundant in testis (2.5, 2.0, 1.1, and 0.9 kilobases), barely detectable in liver (2.0 kilobases), and not detectable in neonatal kidney, adult kidney, brain, heart, or spleen. In the ERC lines, p15INK4B was expressed as a single 2.0-kilobase transcript observed only in those cell lines in which the gene was detected by Southern blot analysis. However, neither p15INK4B nor p16INK4 were deleted in 12 of 12 primary kidney tumors examined, suggesting that deletion of these genes is not directly involved in the process of renal tumor development but may be related to tumor progression or autonomous growth in vitro. A panel of rat kidney epithelial cell lines chemically transformed in vitro (TRKE lines) that had high-frequency monosomy 5 were also examined, but deletion of p15INK4B and p16INK4 was observed in only one of six of the TRKE lines. To our knowledge, this is the first reported investigation of these genes in rodent tumors and cell lines, and its data support the theory that alterations of genes located in the INF region of rat chromosome 5 may play a role in rodent cell transformation.

Animals↗

Clonality study by fluorescence in situ hybridization of a patient with refractory anemia with ringed sideroblasts and monosomy 7.

Myelodysplastic syndromes (MDS) are stem cell diseases but it is still controversial whether chromosomal abnormalities occurring in these disorders affect a multipotent stem cell or a committed progenitor. We studied a case of refractory anemia with ringed sideroblasts (RARS) and monosomy 7 in 100% of examined metaphases. Using the fluorescence in situ hybridization (FISH) technique with a probe specific for the centromeric region of chromosome 7, we demonstrated that 15% of BM cells fixed in acetic acid/methanol exhibited a normal diploid karyotype. Applying the FISH technique on PB cells smeared onto a slide, we observed that lymphocytes maintain two chromosomes 7, whereas other leukocytes exhibited monosomy 7. Our study confirms that chromosomal abnormalities found in MDS can occur in cells capable of differentiation along granulocytic and monocytic lineages, but not along the lymphocytic lineage.

Anemia, Sideroblastic↗

Philadelphia-chromosome-positive, monosomy 7 biphenotypic acute mixed lineage leukemia in adults: a pluripotent stem cell disorder.

Two adult patients with acute mixed lineage leukemia (AMLL) having combined Philadelphia chromosome (Ph1) positivity and monosomy 7 are presented. The phenotypes of leukemic blasts from both cases were almost same (early B-lymphoid lineage and myeloid lineage); CD10+, CD13+, CD19+. HLA-DR+, and dual-color analysis showed simultaneous expression of CD10 (CD19) and CD13 antigens in individual blasts (biphenotypic) in both cases. On molecular analysis, the leukemic blasts showed rearrangement in the first intron of the BCR gene with breakpoint just outside of 3' end of m-BCR-2 (bcr 3) in case 1, and in the M-BCR in case 2. Immunoglobulin heavy chain gene (IgH) rearrangement was noted in both cases, but rearrangement of the T-cell receptor beta-chain gene (TCR beta) was detected only in case 1. Clinically, both cases achieved complete remission by the combination chemotherapy consisting of L-asparaginase, doxorubicin, vincristine, and prednisolone (L-AdVP). In remission, all these molecular abnormalities disappeared in both patients. These results suggest that the Ph1-positive and monosomy 7 AMLL in adults is de novo acute leukemia with both early B-lymphoid and myeloid phenotypes and may arise from malignant transformation of pluripotent stem cell, and expresses a heterogenous rearrangement pattern of the BCR gene.

Acute Disease↗

Spontaneous hematological remission in a boy with myelodysplastic syndrome and monosomy 7.

We report the case of a 14-month-old boy with myelodysplastic syndrome (refractory anemia with blast excess) and bone marrow monosomy 7. Within 2 years after presentation hematological remission gradually occurred without any chemotherapy. After the patient had received three transfusions within the first 4 months, red cell production normalized. However it took 18 more months for neutropenia to resolve. The patient is well 34 months after the first presentation. Molecular analysis of the bone marrow blasts showed no mutations of the ras genes or of the FLR-exon of the NF-1 gene. To our knowledge this is the first report of monosomy 7 syndrome with spontaneous hematological remission.

Base Sequence↗

DCC tumor suppressor gene is inactivated in hematologic malignancies showing monosomy 18.

DCC (deleted in colorectal cancer) is a candidate tumor suppressor gene recently identified on chromosome band 18q21. Loss of one DCC allele or decreased DCC expression occurs in more than 70% of colorectal cancers, suggesting that DCC inactivation constitutes a critical event in the development of these tumors. Using polymerase chain reaction amplification of cDNA, we have studied DCC expression in bone marrow from 4 patients with leukemia (1 chronic myeloid leukemia-blastic crisis, case 1; 1 acute myeloid leukemia, case 2; 1 T-cell acute lymphoblastic leukemia [ALL], case 3; 1 B-cell ALL, case 4) showing loss of one DCC allele due to monosomy 18. We also studied DCC expression in multiple control samples, including normal lymphocytes, normal tonsillar tissue, and leukemias without 18q abnormalities. Four primer pairs consistently amplified the predicted DCC sequences from cDNA prepared from all control samples. However, in samples with monosomy 18, DCC transcripts were either not detected (case 1) or detected at a very low level (cases 2, 3, and 4). Southern analysis showed no structural rearrangement of the remaining DCC locus in all leukemia samples. Thus, loss of DCC expression was demonstrated in association with loss of one DCC allele in all cases tested. These results suggest that, as for colorectal tumors, the inactivation of DCC can have a role in the development of hematologic malignancies.

Adult↗

Monosomy 7 and activating RAS mutations accompany malignant transformation in patients with congenital neutropenia.

Individuals with severe forms of congenital neutropenia suffer from recurrent infections. The therapeutic use of recombinant human granulocyte colony-stimulating factor (rhG-CSF) to increase the neutrophil count is associated with fewer infections and an improved quality of life. However, the long-term effects of this new therapy are largely unknown. In particular, it is unclear if myeloid leukemia, a known complication of some forms of congenital neutropenia, will occur with increased frequency among patients who receive long-term treatment with hematopoietic growth factors. We report 13 patients with congenital disorders of myelopoiesis who developed leukemic transformation with either myelodysplastic syndrome (MDS) or acute myelogenous leukemia (AML) and 1 who acquired a clonal cytogenetic abnormality without evidence of MDS or AML while receiving rhG-CSF. The bone marrows of 10 patients showed monosomy 7 and 5 had activating RAS mutations. These abnormalities were not detected in pretreatment bone marrows and cessation of rhG-CSF was not associated with either clinical improvement or cytogenetic remission. We conclude that patients with severe forms of congenital neutropenia are at relatively high risk of developing MDS and AML. The occurrence of monosomy 7 and RAS mutations in these cases suggests that the myeloid progenitors of some patients are genetically predisposed to malignant transformation. The relationship between therapeutic rhG-CSF and leukemogenesis in patients with severe chronic neutropenia is unclear.

Adolescent↗

Variable expression of phenotype in offspring with partial monosomy 7q and partial trisomy 8p in a family with a rcp (7;8)(134;p12) translocation.

We report a female fetus with partial 7q monosomy and partial 8p trisomy, as the unbalanced product of a familial balanced reciprocal translocation; rcp t(7;8)(134:p12)mat. Among pregnancies from translocation carriers in this family, there has been a high incidence of first trimester miscarriages. Three unbalanced offsprings with a partial 7q monosomy and partial 8p trisomy were diagnosed after prenatal investigations. One female fetus with this unbalanced karyotype has previously been reported. She had a multiple congenital anomalies (MCA) syndrome. In contrast, the present female fetus with the same abnormal karyotype shows only mild facial dysmorfism.

Chromosomes, Human, Pair 7↗

X-chromosome monosomy in an infertile female llama.

A 3-year-old female llama was examined because of a history of infertility and apparent anovulation. The llama had indifferent behavior when penned with a male, but eventually would assume sternal recumbency for breeding. On examination, the llama was underweight and small in stature. The uterine horns and ovaries could not be identified during palpation or ultrasonography per rectum, and the cervix was dilated when examined with a speculum. Chromosomal preparations of lymphocytes and skin fibroblasts were performed; all cells examined had a 73, X karyotype (X-chromosome monosomy). To our knowledge, this is the first report of a chromosomal anomaly in a llama. Signs seen in this llama were similar to those seen in mares with X-chromosome monosomy. This condition should be considered in the differential diagnosis of infertility in llamas that fail to ovulate, especially if other abnormalities such as indifferent sexual behavior and short stature are present.

Animals↗