Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “CHROMOSOME ABNORMALITIES”

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 559 records · Page 31Linked to original sources

Chromosome abnormalities in hairy cell leukaemia variant.

We describe chromosome abnormalities in 6 patients with hairy cell leukaemia (HCL) variant, a rare B-cell disorder with clinical and laboratory features intermediate between HCL and B-prolymphocytic leukaemia (B-PLL). All but one had marked splenomegaly and a raised white blood cell count (median 40 x 10(9)/l) with over 80% nucleolated hairy cells. These cells had a B-cell immunophenotype distinct from that of typical HCL. All patients but one are alive with stable disease with a median follow-up of 60 months. Numerical chromosome changes included loss of chromosomes 2, 3, 4, 6, 10, 19, 21, and X. three cases had translocations involving the immunoglobulin gene regions: t(14;17)(q32;q11), t(14;22)(q32;q11), and t(2;8)(p11.12;q24). Immunocytochemistry demonstrated the presence of the MYC protein in cells from the case with t(2;8) but not in two others. Other structural abnormalities included t(3;10)(q27;q22) and t(3;12)(q27;q13) in the same patient, der(17)t(7;10;17)(p11;q27;q22), t(1;3)(q25;p21), t(8;21)(p12;q11), t(17;21)(p11;p11), del(6)(q15), del(7)(q34), and del(14)(q24).

Aged↗

Chromosome abnormalities in neurological diseases.

The current status of research into chromosomal abnormalities in neurological diseases is reviewed. The only possible association between chromosome aberration and neurological disorder is found in ataxia telangiectasia and in tumours of the nervous system. In the remaining diseases reviewed, no specific association was confirmed. This was expected to some extent, since the majority of these diseases (spinal muscular atrophies, muscular dystrophies, etc.) are due to single gene defects.

Chromosome Aberrations↗

Fetal macrocytosis in association with chromosomal abnormalities.

Mean red cell volume (MCV) was determined in 264 fetuses between 15-41 weeks. After exclusion of anemic, hypoxic, and chromosomally abnormal fetuses, the MCV in 208 umbilical venous samples was shown to decrease with gestation (r = 0.64; P less than .001), and a normal range was constructed by linear regression analysis. An elevated MCV was found in both fetuses with triploidy, in four of five with monosomy X, and in four of ten with trisomies 18 or 21. The MCV was similarly raised in four of five fetuses with gross anomalies in whom cytogenetic cultures had failed. Significant correlations were found in chromosomally abnormal fetuses between the elevation in MCV and both the nucleated red cell (r = 0.69; P less than .01) and reticulocyte counts (r = 0.57; P less than .05). There was a similar correlation with nucleated red cells in 16 severely anemic fetuses with Rh disease, 12 of whom had a raised MCV. Elevation in MCV was unrelated to hypoxia. Macrocytosis had a sensitivity of 71% and a specificity of 95% in the second trimester for predicting an abnormal karyotype in nonanemic fetuses (kappa index 0.60). Fetal MCV may provide clinically useful information while one awaits culture results. We suggest that karyotyping be considered in fetuses undergoing blood sampling for other indications in whom the MCV is raised.

Anemia↗

Chromosome abnormalities as a cause of infertility in mares.

Chromosomal abnormalities have been detected in seven mares isolated by their poor reproductive performance. All had small or rudimentary gonads and absent or irregular oestrous cycles. Two mares had an XO genotype, one was a 65,XXX female and another a 64,XY sex-reversed female. Two other mares were sex chromosome mosaics of the 63,X/64,XX type. The seventh mare showed a normal female karyotype but a small extra autosomal fragment was found in a few cells.

Animals↗

Second-trimester unconjugated oestriol levels in maternal serum from chromosomally abnormal pregnancies using an optimized assay.

Second-trimester unconjugated oestriol (UE3) levels were measured retrospectively in maternal serum from 78 chromosomally abnormal pregnancies and 390 matched controls using a radioimmunoassay kit (Amersham AMERLEX-M) optimized for use in the second trimester. Reduced levels of UE3 were found in a group of 49 Down's syndrome pregnancies with a median UE3 level of 0.79 multiples of the median (MOM) of the controls. Four trisomy 18 pregnancies had UE3 levels less than 0.7 MOM. There was a highly significant level of correlation between alpha-fetoprotein (AFP) and UE3 levels in the controls (r = 0.25, p < 0.01), the Down's syndrome pregnancies (r = 0.44, p < 0.01), and the other chromosome abnormalities (r = 0.61, p < 0.01). When used as an additional marker to AFP and human chorionic gonadotrophin in screening for Down's syndrome, UE3 does not appear to add to the sensitivity of such screening.

Chromosome Aberrations↗

Chromosome abnormalities in 447 couples undergoing intracytoplasmic sperm injection--prevalence, types, sex distribution and reproductive relevance.

Chromosomal abnormalities are thought to be a major contributor to the genetic risks of infertility treatment by intracytoplasmic sperm injection (ICSI). Apart from abnormalities arising de novo, abnormal karyotypes in pregnancies conceived through assisted reproductive technology may be directly derived from predisposing parental aberrations. In a prospective study we have analysed the chromosomes of 868 male and female patients prior to planned ICSI treatment. A total of 33 aberrant karyotypes was diagnosed, corresponding to an abnormality rate of 7.6% per couple or 3.8% per individual studied. Even though male factor infertility was twice as common as female factor infertility in this cohort, 24 of the chromosomal abnormalities were found among the women. Low-level mosaicism for numerical sex chromosome anomalies was diagnosed in 20 individuals, and one patient had the triple X karyotype. With respect to structural chromosomal anomalies, we found six reciprocal and three Robertsonian translocations, two paracentric inversions and one marker chromosome. Many of the aberrations that we diagnosed could be classified as carrying only a small to moderate reproductive risk. Given the high rate of abnormal karyotypes among the female subjects, we suggest that not only the males, but both partners should be routinely karyotyped prior to ICSI.

Adult↗

Cell selection in vivo in normal/aneuploid chromosome abnormalities.

Cytogenetic follow-up examination has been made of the 9 mixoploid children found among 11 148 newborn children. In 4 of the 9 children there was a significant increase in the frequency of the cell line with normal chromosome constitution and a significant decrease in the normal cell line was found in 1 child. In 4 there was no significant difference from the first to the last examination. The frequency of the cell line with normal chromosomes increased from 32-68% to between 93-97% in 3 cases and to 86% in 1. The possibility that children with mixoploid chromosome abnormalities at birth will reveal no cell line with chromosome abnormality in lymphocyte cultures as adults in spite of having clinical signs of the chromosome aberration found in one cell line at birth is discussed.

Age Factors↗

Chromosomal abnormalities in oocytes.

Since the beginning of in vitro fertilization (IVF), basic research has provided insight in the field of human reproduction, especially in genetics. Indeed, the contribution of chromosomal abnormalities to oocyte disorders and impaired embryonic development is now well known. Of oocytes that fail to fertilize after in vitro insemination, 26.5% have been found to be abnormal, with 13.3% showing hypohaploidy, 8.1% hyperhaploidy, 1.6% structural abnormalities and 3.5% diploidy. The total incidence of abnormalities seems to be correlated with the fertility status of the woman. It is higher in oocytes from women with tubal or unexplained infertility than in those from women whose husband's infertility is the sole cause of infertility in the couple. Although few oocytes recovered during natural cycles have been studied, gonadotropins, which are widely used to stimulate follicle growth and ovulation, do not increase the risk of abnormalities. The effect of maternal age on fetal aneuploidy, well documented at birth, has not been unambiguously shown to result from an increase in the frequency of aneuploid oocytes. Intra- and extra-follicular influences (perifollicular microvasculature, oxygenation, and the presence of residues from cigarette smoke) may disturb maturation, leading to immaturity and aneuploidy. Thus, oocyte meiosis is very sensitive to endogenous and exogenous factors that could result in oocytes with chromosomal abnormalities and therefore, abnormal zygotes.

Chromosome Aberrations↗

[Chromosome abnormality and dominant lethality among the F1 generation of mice after gamma-ray irradiation].

This paper reports on the relationship between chromosome abnormality or dominant lethality and dosage of 0.15-1.56 Gy 60Co gamma-ray irradiation in the F1 generation of mice. The irradiated female mice were mated at 7-12 days after irradiation with unirradiated or irradiated at 22-28 days after irradiation. The fetuses aged 9.5-11 days were recovered from the uterus and lethality and chromosome aberrations were investigated. Results suggested that the rate of fetus with chromosome abnormality increased with dose, and so did dominant lethality rate, and both could fit linear relationship. Increase of translocation carriers in the F1 mice was observed at the dose level of over 1.0 Gy.

Animals↗

Clonal chromosome abnormalities in neoplastic cells: evidence of genetic instability?

All types of neoplasia that have been extensively examined, be they benign or malignant, are characterized by acquired chromosomal aberrations. In many instances, the changes are specific for the tumour type in question. Some tumours, even among the most malignant ones, have only a single chromosomal abnormality, whereas others have numerous secondary aberrations. Although an overall parallel exists between a tumour's malignancy and the number and complexity of its chromosomal changes, in some situations altered selection pressure may give rise to reduced karyotypic complexity with time. The effective causes of both primary and secondary chromosomal changes of neoplastic cells are largely unknown. In some special situations, in particular therapy induced acute leukaemias, exposure to a carcinogenic agent seems to have specifically induced the leukaemogenic genetic rearrangement. Patients carrying malignant neoplasms have in most studies been found to have normal chromosomal stability in their non-neoplastic somatic cells, both generally and at the genomic regions that are rearranged in their tumours. Although abnormal chromosomal fragility of cells belonging to the neoplastic parenchyma has not been convincingly demonstrated, the existence of such instability remains a viable, perhaps even necessary, hypothesis. To look for a unifying mechanism common to all neoplastic processes seems simplistic: specific mutagenesis giving rise to both primary and secondary chromosomal changes is likely to occur in some tumours, whereas in others random aberrations are generated, and at least as far as the secondary ones are concerned often at a higher than normal rate, followed by Darwinian selection for fitness within the host organism.

Acute Disease↗

Prenatal diagnosis for chromosome abnormalities: past, present and future.

Prenatal diagnosis for chromosome abnormalities has been available for over 30 years. The most common referral indication is a raised risk of Down's syndrome, and diagnosis has, until recently, been carried out by culture of cells from invasive prenatal sampling, followed by full karyotype analysis, with a waiting time of around 2 weeks for results. More recent developments in fluorescence in situ hybridisation (FISH) and quantitative fluorescence-PCR techniques have led to rapid 1-2 d reporting for Down's syndrome, opening the way to the possibility of targeted testing based on referral indication, thus reducing the incidence of difficult counselling issues and potentially unnecessary pregnancy terminations following the unexpected discovery of anomalies such as balanced chromosome rearrangements. The future of prenatal diagnosis must lie in the non-invasive diagnosis of Down's syndrome using fetal cells from maternal circulation.

Chromosome Aberrations↗

Prenatal diagnosis of chromosome abnormalities in the presence of fetal structural defects.

A chromosomal abnormality was found in 42 (10.9%) out of 386 fetuses with a structural defect. Thirty-five of these were diagnosed prenatally, following ultrasonic detection of one or more structural anomalies and associated pathology such as marked intrauterine growth retardation and polyhydramnios. Termination of pregnancy was carried out in 16 fetuses aged less than 26 weeks, intrauterine and neonatal death occurred in 20 cases, the remaining 6 infants were alive at 3 months. The poor outcome in these pregnancies emphasizes the need for prenatal chromosome analysis in the presence of a fetal structural defect.

Chromosome Aberrations↗

Complex chromosomal abnormalities in a patient with refractory anemia with excess blasts (RAEB).

We report a new case of refractory anemia with excess blasts (RAEB) having complex chromosomal abnormalities. The 5q- associated with RAEB and other preleukemic syndromes was present in 100% of the cells; however, 60% of the cells had a highly unusual derivative chromosome involving the short arm of chromosome 1 and the long arm of chromosome 5, i.e., t(1;5)(p36;q14). Although the patient presented with highly complex chromosomal abnormalities, his initial clinical presentation was that of typical refractory anemia with excess blasts. Shortly after diagnosis (7 months), the patient developed acute leukemia.

Anemia, Refractory, with Excess of Blasts↗

Chromosomal abnormalities in mentally retarded children in the Konya region--Turkey.

Etiology of mental retardation is diverse. 120 Students from 11 special training, education, and rehabilitation subclasses were investigated cytogenetically for determining the contribution of chromosomal abnormalities to mild mental retardation. 23 of the 120 children (19%) had chromosomal abnormalities: thirteen cases a classical trisomy 21 (the male:female ratio was 9:4), three a balanced autosomal reciprocal translocation, one a pericentric inversion of chromosome 9, and six fragile-X syndrome (The male:female ratio was 5:1).

Adolescent↗

Additional chromosomal abnormalities to Ph during the clinical course in patients with acute lymphoblastic leukemia.

Cytogenetic findings obtained during the clinical course in two patients (one child and one adult) with Ph-positive acute lymphoblastic leukemia (ALL) are reported. Chromosomal abnormalities in addition to Ph chromosome were detected in both patients. At the beginning of the disease, such abnormalities consisted of the trisomy of chromosome 1 and monosomy of chromosomes 8 and 9, with a sub-line 45, XY, Ph, -8 in the child; in the adult patient a hyperdiploid clone with 57-59 chromosomes and Ph duplication was present. At relapse, the same karyotypic anomalies reappeared in the child, whereas in the adult a high frequency of chromosomal rearrangements, such as ring and dicentric chromosomes, was observed after cranial irradiation. The occurrence of chromosomal abnormalities additional to Ph during the clinical course in ALL patients is discussed, taking into account data from the literature concerning the lymphoid blastic crisis in chronic myeloid leukemia patients.

Adolescent↗

Chromosome abnormalities after chlorambucil therapy of polycythaemia vera.

Bone marrow chromosomes were studied in 2 patients with polycythaemia vera (PV) at the time of diagnosis and several times subsequently during therapy with chlorambucil. Both patients were normal in the initial study, but later developed pathological diploid cell lines with structural chromosome abnormalities. Case 1 presented after 25 months of myelosuppressive therapy a deletion of chromosome no. 12, del (12) (p11), in 60% of the diploid cells. 10 months later all studied cells in the marrow contained this deletion. In addition, the deletion of chromosome no. 20, described as characteristic for PV, was found in 3 cells. Case 2 demonstrated after 40 months on chlorambucil the presence of a balanced translocation, t (1;5) (p36;q31) in 90% of the cells. In none of the patients were any definite clinical, laboratory or morphological signs of an approaching leukaemic transformation of the polycythaemic disorder present.

Aged↗

Prognostic significance of posttransfusion hepatitis and chromosomal abnormalities in adult acute nonlymphocytic leukemia.

In a retrospective analysis, we studied the effects of posttransfusion hepatitis (non-A, non-B) and chromosomal leukemia upon the overall times of adult patients with acute nonlymphocytic leukemia (ANLL). Seventy-two patients treated at the University of Chicago from 1970 to 1981 were evaluable. The complete remission (CR) rate for the entire group of patients was 33%, and the median survival was 246 days. Twenty-eight patients (39%) developed hepatitis, and 42 (61%) did not. The CR rate of the patients with hepatitis was 54%, and the median survival of this group was 615 days. In comparison, the CR rate for those who did not develop hepatitis was 20%, and their median survival was 136 days (p less than 0.0001). The groups were comparable in terms of race, sex, initial hematologic parameters, chromosomal abnormalities, dates of treatment, chemotherapy treatment programs, and French-American-British (FAB) subtype, but the median age of the patients who did not develop hepatitis was higher than that of the others. Patients who had normal karyotypes and who developed hepatitis had the best overall prognosis (median survival of 738 days). Patients with abnormal karyotypes who failed to develop hepatitis had the shortest survival times (median, 124 days). The group of patients who had the longest survival (median, 1130 days) included those over 40 years old, with posttransfusion hepatitis, and with normal karyotypes. The development of posttransfusion hepatitis and the presence of chromosomal abnormalities appear to be important, but opposite, indicators of overall prognosis for patients with ANLL.

Adolescent↗

Chromosomal abnormalities associated with congenital contractures (arthrogryposis).

In a study of 350 patients with multiple congenital contractures (arthrogryposis), 80 (23%) patients had mental retardation or were developmentally delayed. Out of that group of 80 patients, 13 (16%) were found to have abnormal karyotypes. Two of the thirteen had a family history of chromosomal abnormalities without congenital contractures, therefore, 11 patients had chromosomal anomalies which appeared to be associated with the congenital contractures. Five of the eleven (45%) had chromosome mosaicism, three of those had tissue mosaicism. Two had abnormal skin fibroblast cell lines and normal peripheral leukocyte chromosome studies and one had a normal bone marrow karyotype with abnormal peripheral leukocyte chromosome studies. Chromosome studies were done in these patients with congenital contractures because of developmental delay and multisystem involvement, or recognition of clinical features typical of a chromosomal syndrome. We recommend first lymphocyte; and if those are normal, then fibroblast studies be done on all patients with multiple joint contractures and developmental delay, particularly if unusual facial features or multisystem abnormalities are present.

Abnormalities, Multiple↗