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Chromosome abnormalities and spontaneous fetal death following amniocentesis: further data and associations with maternal age.

The pooled results are presented of two North American surveys concerning spontaneous fetal deaths of conceptuses with cytogenetic abnormalities diagnosed prenatally whose mothers had declined elective abortion. The rate of fetal death of those with nonmosaic genotypes associated with Down syndrome was 30.1% (95% confidence interval of 19.0%-42.0%), which is almost identical with the difference of 30% previously estimated between rates observed at amniocentesis and in live births. The fetal death rate for (nonmosaic) 47,+18 was 68.0% (95% confidence interval of 46.5%-85.1%), close to the estimated difference of 75% between rates at amniocentesis and in live births for this genotype. For other nonmosaic genotypes, the rates (and 95% confidence intervals) were: 47,+13, 42.9% (9.9%-81.6%); 47,XXX, 0% (0%-9.0%); 47,XXY, 8.1% (0.8%-11.0%); 47,XYY, 3.0% (.08%-15.8%); for balanced translocations and inversions, 2.8% (0.3%-9.8%); and for markers, variants, and fragments, 0% (0%-12.8%). For 45,X, the rate was 75.0% (42.8%-94.5%), in contrast to the rate for 46,XX/45,X of 10.5% (1.3%-33.1%) and for structural X abnormalities associated with Turner syndrome of 0% (0%-60.2%). The rate for nonmosaic 45,X is significantly different from that for either of the other two categories associated with Turner syndrome. The maternal age of nonmosaic 47,+21 fetuses that survived to live birth was 39.1 +/- 6.2, not significantly different from the rate for fetal deaths: 39.5 +/- 3.8. The observations provide no support for opposing hypotheses by other groups that maternal age is positively or negatively associated with fetal death of 47,+21 conceptuses. For other chromosome abnormalities, maternal ages of fetal deaths are slightly lower than for live births, but none of the differences are significant. The rates of spontaneous fetal deaths derived here are likely to be pertinent to genetic counseling. Their use in adjusting the rates of abnormalities diagnosed at amniocentesis will enable derivation of predicted contemporary live-birth prevalence rates of abnormalities that would be observed in absence of selective abortion.

Adult↗

Amniotic fluid-AFP in Down syndrome and other chromosome abnormalities.

80.2 Per cent of 111 Down syndrome pregnancies had anmiotic fluid (AF) alpha fetoprotein (AFP) levels on or below the median and 10.8 per cent at or below 0.5 MoM compared with 41.9 and 1.4 per cent of controls. These differences were even more striking when the gestational age was less than 18 weeks compared with greater than or equal to 18 weeks. No such association was seen for other chromosome abnormalities including trisomy 18,45,X and mosaics, 47,XXY,47,XXX, and other structural abnormalities and triploidy, even when high levels due to defects such as omphalocele and cystic hygroma were excluded. All cases of trisomy 13 and 80 per cent with 47,XYY had AF-AFP levels above the median. Selection of cases for karyotyping by a low level of AF-AFP would clearly fail to detect aneuploidies other than Down syndrome and is not recommended. A possible weak association between low maternal serum (MS) and AF-AFPs in Down syndrome was most evident at less than 18 weeks, suggesting that MS screening between 16 and 18 weeks may be the most informative time.

Adult↗

Discrimination between leukaemia and non-leukaemia-related chromosomal abnormalities in the patient's lymphocytes.

The inability to measure precancer-related genetic damage accurately in blood cells of patients with leukemia or lymphoma has prevented the use in such patients of available biodosimetric methods to determine prior exposure to clastogenic agents. This is because a substantial amount of disease-related genetic damage appears in the blood cells of these patients, thus masking genetic damage that may have been caused prior to the disease. We describe a new approach that may be used to measure precancer-related chromosomal aberrations in such patients by totally separating the affected T lymphocytes from the malignant B lymphocytes. The approach employs stable chromosome translocations and will detect prior exposures above the detection limit of approximately 0.05-0.1 Gy. The utility of this approach is illustrated by using blood lymphocytes from a nuclear dockyard worker who claims his B cell leukaemia was induced by work-related radiation exposures. Blood lymphocytes were obtained after diagnosis of the disease, but prior to therapy, and measurements were made of the frequency of chromosomal abnormalities in PHA-stimulated lymphocytes without prior separation of T and B cells and in T lymphocytes after complete separation from B cells using a rosetting technique. Results show that the separation of T cells prior to PHA stimulation eliminates the cancer-related chromosomal damage and thus appears to facilitate biodosimetry of pre-cancer exposures in such patients.

Adult↗

Delayed meiotic development and correlated death of spermatocytes in male mice with chromosome abnormalities.

The kinetics of germ-cell development were examined in random-bred adult Swiss mice by means of tritium autoradiography. Comparisons were made between males with normal (+/+) and abnormal karyotypes: Rb(11.13)4Bnr/+ and T(1;13)70H/+ heterozygotes, T70H tertiary trisomics, and T70H translocation trisomics. The time taken for the first wave of labelled cells to progress from premeiotic S-phase to diplotene and then on to the second meiotic metaphase was estimated in each stock, and rates of increase of labelled meiotic figures were measured. The S-phase to diplotene interval did not differ significantly among the different genotypes, taking from 10 days, 16 h to 10 days, 19 h. In Rb4Bnr/+, T70H translocation trisomic, and T70H tertiary trisomic males, however, labelled meiotic figures accumulated at a lower rate, particularly in the tertiary trisomics. A cell delay for some meiocytes was thus indicated during meiotic prophase. A correlation was seen between the degree of meiotic delay and severity of reduction in sperm count. The period from late diplotene to metaphase II was also found to be longer in T70H tertiary trisomics than in controls (+/+) or other chromosomally abnormal males.

Animals↗

Longitudinal studies of chromosomal abnormalities and reticulum cell proliferation in New Zealand Black mice.

A longitudinal study of 40 New Zealand Black (NZB) mice and 20 BALB/c control animals was performed. A significant association was observed between the presence of acquired spleen-cell aneuploidy at some time during life and development of histological evidence of reticulum-cell neoplasia in individual animals. This finding is compatible with the hypothesis that aneuploid clones which arise in the spleens of aging NZBs are at least potentially neoplastic. However, no relationship between histologically neoplastic reticulum cell proliferation and aneuploidy was apparent in single splenic specimens obtained from NZB mice of various ages. This lack of association indicates that failure to detect chromosomal abnormalities on direct study of cells from a tumor cannot be taken as evidence that the neoplastic cells themselves lack such abnormalities.

Aneuploidy↗

Characteristics of t(8;21) acute myeloid leukemia (AML) with additional chromosomal abnormality: concomitant trisomy 4 may constitute a distinctive subtype of t(8;21) AML.

t(8;21)(q22;q22) is the most frequently observed karyotypic abnormality associated with acute myeloid leukemia (AML), especially in FAB M2. Clinically, this type of AML often shows eosinophilia and has a high complete remission rate with conventional chemotherapy. t(8;21) AML is also frequently associated with additional karyotypic aberrations, such as a loss of the sex chromosome; however, it is unclear whether these aberrations change the biological and clinical characteristics of t(8;21) AML. To investigate this issue, 94 patients with t(8;21) AML were categorized according to their additional karyotypic aberrations, which were detected in more than three cases, and then morphologic features, phenotypes, expression of cytokine receptors, and clinical features were compared to t(8;21) AML without other additional aberrant karyotypes. t(8;21) AML with loss of the sex chromosome and abnormality of chromosome 9 were found in 27 cases (29.3%) and 10 cases (10.6%), respectively; however, no differences were observed from the t(8;21) AML without other additional karyotypes in terms of morphological and phenotypic features. There was also no significant difference in the clinical outcome among these three groups. On the other hand, trisomy 4 was found in three cases (3.2%) and these cells showed low expressions of CD19 (P=0.06) and IL-7 receptor (P=0.05), and high expressions of CD33 (P=0.13), CD18 (P=0.03), and CD56 (P=0.03) when compared to t(8;21) AML without additional karyotypes. Moreover, all three t(8;21) AML cases with trisomy 4 did not show eosinophilia in their bone marrow and died within 2.4 years. These observations suggest that additional karyotypic aberration, t(8;21) with trisomy 4 is rare, but it may constitute a distinctive subtype of t(8;21) AML.

Adolescent↗

Sustained improvement in anemia with low-dose recombinant human erythropoietin therapy in a patient with hypoplastic myelodysplastic syndrome and chromosomal abnormalities.

We present a case report of a 55-year-old male patient with hypoplastic myelodysplastic syndrome (MDS, refractory anemia) in which a good response to recombinant human erythropoietin (rhEPO) has been maintained for more than 60 months. There is with no evidence of progression to high risk MDS or acute leukemia, although he was predicted to be a low-responder to rhEPO therapy because of very high serum EPO levels (5,260 mU/ml), a history of multiple transfusions, chromosomal abnormalities (47,XY,+8) and severe thrombocytopenia. Since he received rhEPO with no adverse effects, it may be valuable to try rhEPO treatment at least one time for low-risk MDS patients, depending on red cell transfusion requirements.

Anemia, Refractory↗

Effects of trypsin on X-ray-induced cell killing, chromosome abnormalities and kinetics of DNA repair in mammalian cells.

When cells are trypsinized before irradiation a potentiation of X-ray damage may occur. This is known as the 'trypsin effect'. Potentiation of X-ray damage on cell killing was seen in V79 Chinese hamster cells but was marginal in Chinese hamster ovary (CHO K1) cells and not evident in murine Ehrlich ascites tumour (EAT) cells. Trypsinization did however increase the number of X-ray-induced chromosomal abnormalities in all 3 lines. To investigate the possibility that trypsin acts by digestion of proteins in chromatin, further experiments were performed to monitor DNA damage and repair. Induction of DNA breaks by X-rays was unaffected by trypsin but trypsinized EAT (suspension) cells repaired single-strand breaks (ssb) less rapidly than controls indicating an inhibitory effect of trypsin on ssb repair. However double-strand break (dsb) repair was unaffected by trypsin. It was also found that the EDTA solution in which the trypsin was dissolved also contributes to the inhibition of dsb repair. The results show that trypsinization can enhance X-ray-induced cell killing, chromosomal damage and DNA repair, the effect varying between cell lines.

Animals↗

Chromosome abnormalities in myelofibrosis.

Cytogenetic analysis was performed on megakaryocyte-enriched cell fractions obtained by separation on discontinuous Percoll gradients from blood, bone marrow, and ascitic fluid of 12 patients with myelofibrosis with myeloid metaplasia (MMM). The most common abnormalities appeared to involve chromosomes 1, 3, 7, 8, 11, 13, 21 and 22. Although no specific chromosome rearrangements were observed in megakaryocytic fractions from different tissues of the patients with MMM, the presence in one case of a 3q-abnormality restricted to polyploid metaphases only, and of a 3q paracentric inversion in another patient, seems to confirm a close relationship between the involvement of chromosome 3 and dysplastic thrombopoiesis.

Chromosome Aberrations↗

Selection of the most common chromosome abnormalities in oocytes prior to ICSI.

So far, all preimplantation genetic diagnosis (PGD) protocols in use produce results after the eggs have been fertilized. However, these approaches are not acceptable for patients with moral objections to the generation and discard of supernumerary zygotes or embryos. In these circumstances, only those oocytes to be replaced may be inseminated. The purpose of this study was to develop a PGD protocol to diagnose first polar bodies (PBs) prior to Intracytoplasmatic Sperm Injection (ICSI) in order to inseminate only those oocytes found to be chromosomally normal. PB biopsy was performed 1 hour after ovum pick up, and after fixation, the PBs were analysed by FISH and the eggs inseminated by ICSI no later than 7 hours after retrieval. One third (33.3%) of the PBs were aneuploid. Fifty-four normal and 12 non-resolved oocytes were injected by ICSI, of which 65% became 2-PN zygotes. Embryo transfer on day 2 was possible in all 10 patients (average maternal age 35.2+/-3.2, range 29-39 years), of which 6 became pregnant with 8 fetuses (28.6% or 8/28 transferred embryos). The results indicate that PB analysis of some common chromosome abnormalities is feasible within time limits imposed by ICSI insemination (6 hours or less).

Adult↗

Multiple chromosome abnormalities in a drug resistant TdT positive B-cell leukemia.

A 17-year old caucasian male presented with B-cell acute leukemia which proved aggressive and refractory to treatment. Cytogenic investigation showed a single clone with a complex karyotype 49,XY,del(2)(p13),+4,del(4)(p11),-6,+i(6)(p),+7,+8, t(8;14), (q24;q32),del(17)(p11). This includes the Burkitt's translocation and a deletion at the site of the immunoglobulin kappa light chain gene. Clonal evolution included tetraploidy, duplication of the derived chromosomes and, terminally, trisomy 1q. Immunological investigation revealed a monoclonal population of B-cell blasts, expressing the kappa light chain, and with an extremely rare combination of SIg and TdT positivity. Immunoglobulin gene rearrangement confirmed monoclonalility. Tetraploidy of the clone and del(17)(p11) have been previously described only in a cell line or at end stage disease in B-ALL. It is suggested that the chromosomal abnormalities present at diagnosis were directly related to the refractory nature of this leukemia.

Acute Disease↗

[Initial symptoms of hematemesis from gastric varix with chromosomal abnormalities of t(2; 8) and 14q+ in a patient with acute lymphoblastic leukemia (FAB: L3)].

A 71-year-old woman was hospitalized because of hematemesis on December 1, 1987. Her white blood cell (WBC) count was 41,200/microliters with 48% of lymphoblasts, and the bone marrow was hypercellular with more than 90% of blasts. The diagnosis of acute lymphoblastic leukemia (ALL) (FAB: L3) was made by morphologic, cytochemical and immunologic studies of the blasts. The examination of fiber gastroscope revealed remarkable varix in the stomach, suggesting portal hypertension accompanied by infiltration of leukemic cells into reticulo-endothelial system. She died of respiratory failure because of bleeding into the trachea. The autopsy disclosed the massive infiltration of leukemic cells into the whole organs. In the chromosome study of the peripheral blood, t(2; 8) and 14q+ were observed, and these chromosomal abnormalities are relatively unusual in patients with Burkitt's lymphoma.

Aged↗

Chromosomal abnormalities associated with neck nodal metastasis in nasopharyngeal carcinoma.

Neck lymphatic metastasis represents the single most important clinical prognostic factor in nasopharyngeal carcinoma (NPC), but underlying genetic mechanisms remain ill defined. In this study 23 samples of primary tumor (PT) and 9 of neck lymph node metastasis (NLNM) obtained from NPC patients were analyzed by comparative genomic hybridization (CGH) coupled with tissue microdissection and degenerate oligonucleotide primer-polymerase chain reaction (DOP-PCR). A similar pattern of chromosomal abnormalities was seen in PT and NLNM, the common aberrations were gains on 5p, 12p, 12q and 18p and deletions on 1p, 3p, 9q, 14q, 17p and 16q. However, NLNMs, but not PTs, also exhibited frequent losses on 9p, 16p, 17q, 20q, 21p, 21q and 22q and gains on 8q and 8p. The most frequent unique aberration in NLNMs was loss on 16p, observed in 100% (9/9) NLNMs tested, as well as loss of 20q, observed in 77.8% of tumors tested. For the first time, we report that a gain on 8p and a loss at 20q is common to NLNMs. The analysis furthermore suggests that specific alterations, e.g. losses of 9p, 16p, 7q, 20q, 21p, 21q, 22q and gains on 8q and 8p are associated with NLNM of NPC, and that these alterations may be involved in the onset and/or progression of a metastatic phenotype.

Chromosome Aberrations↗

Combined effects of misonidazole, microwave hyperthermia, and X-rays on the in vivo sister chromatid exchanges and chromosomal abnormalities of the dbrB tumor and on the survival of its host.

A rapidly proliferating mammary adenocarcinoma designated dbrB growing s.c. in isogeneic female DBA/1J mice in their 278th passage of transfer constituted the experimental host tumor system. A 5-bromodeoxyuridine pellet (2.5 mg/g body weight) was used for sister chromatid exchange analysis of the 0.5-cu cm dbrB tumor. Experiments were performed on Group I, untreated tumor-bearing mice, and Group II, tumor-bearing mice treated with triple agents: misonidazole (1 mg/g body weight); 42.5 degrees microwave hyperthermia for 10 min; and X-rays administered singly or in combination at about 4 hr following the implantation of a 5-bromodeoxyuridine pellet. The X-ray treatments consisted of 400, 1000, 1500, and 2000 rads, respectively. X-rays and hyperthermia were delivered to the tumors directly, while the rest of the mouse body was lead shielded. Survival of the untreated tumor-bearing control mice in Group I was 12 +/- 3 (S.D.) days, whereas the mice in Group II whose tumors were treated with misonidazole, hyperthermia, and 2000 rads of X-rays survived 27 +/- 3 days. 5-bromodeoxyuridine per se had no effect on the survival of the experimental mice. Only a dose of 400 rads administered to the dbrB tumors permitted detailed evaluation of chromosomal analyses, whereas the larger doses of radiation caused cellular destruction. Simultaneous treatment with triple agents resulted in sister chromatid exchanges of 33.78 +/- 0.39/cell as compared with sister chromatid exchanges of 14.74 +/- 0.39/cell of untreated control tumors. This mode of treatment also induced various types of chromosomal abnormalities in the tumor cells.

Adenocarcinoma↗

A survey of attitudes about maternal serum screening for fetal chromosome abnormalities in women 35 years of age and older.

We asked two groups of women their opinion on prenatal diagnosis and maternal serum screening (MSS): group 1 comprised women who had undergone a prenatal diagnostic procedure (amniocentesis or chorionic villus sampling) for advanced maternal age (>/=35 years) and group 2 women who had undergone MSS and were 30-34 years old. Women in group 1 were found significantly less likely to choose MSS over prenatal diagnosis than were women in group 2. The sensitivity of MSS and the age-related risk of chromosome abnormalities influenced opinions on whether to choose MSS or prenatal diagnosis. In both groups, the majority stated that they would accept MSS over prenatal diagnosis, if their obstetrician recommended it.

Adult↗

B cell acute lymphoblastic leukemia (ALL) with a 14q+ chromosome abnormality.

An adult patient with acute lymphoblastic leukemia associated with a 14q+ marker chromosome is presented. The abnormality resulted from a translocation of material from the long arm of chromosome 11. The leukemic cells were found to be B cells on the basis of surface immunoglobulins, lack of receptors for sheep erythrocytes, and a characteristically low level of adenosine deaminase activity. In other patients with ALL studied by us or reported by others in whom chromosome banding was done, a 14q+ chromosome was present in only one instance, also a case of B cell ALL. These two cases are the only examples of B cell ALL studied with chromosome banding reported to date. The frequent occurrence of a 14q+ chromosome in other malignant lymphoproliferative diseases of B cell origin suggests that a general association may exist between the 14q+ abnormality and B cell neoplasms. Cytogenetic analysis may therefore be useful in defining subtypes of ALL and in relating specific chromosomal abnormalities to lymphoproliferative disorders.

Adenosine Deaminase↗

Immunophenotype of mitotic cells with clonal chromosome abnormalities demonstrating multilineage involvement in acute myeloid leukemia.

Eleven patients with acute myeloid leukemia (AML) were studied with a technique that simultaneously identifies cytogenetic abnormality and immunophenotype of the same mitotic cell. To determine the cell lineages with abnormal karyotypes, monoclonal antibodies in the alkaline phosphatase-antialkaline phosphatase (APAAP) detection procedure were used. The granulocytic/monocytic lineage was involved in the leukemic process in all 11 patients. In nine patients, we also detected abnormal karyotypes in the erythrocytic and/or megakaryocytic lineages. All four patients with secondary AML showed involvement of the granulocytic/monocytic, erythrocytic, and megakaryocytic lineages into the leukemic process, as compared with five of seven patients with de novo AML. One patient with trisomy 8 showed erythrocytic participation in the leukemic process, but in another the erythrocytic lineage had only normal karyotypes. Thus, in AML, the chromosome abnormalities apparently usually originate at the multipotent progenitor cell stage, since in addition to granulocytic/monocytic lineages, erythrocytic and/or megakaryocytic lineages were also involved. Some patients show involvement of granulocytic/monocytic lineages only, however, suggesting that the target cell belongs to a more mature committed progenitor cell stage.

Adult↗