Showing papers on "Karyotype published in 1970"

A Human Tissue Culture Cell Line from a Transitional Cell Tumour of the Urinary Bladder: Growth, Chromosome Pattern and Ultrastructure

Abstract: Cell cultures were made from 18 human bladder tumours. Three cell lines were maintained for seven transfer generations, but all had a "fibroblastic" morphology and a normal diploid karyotype. A fourth line has been maintained for over 80 transfer generations. This was derived from a well differentiated papillary tumour of bladder. Morphologically the light and electron microscopic structure of the cells resembled that of bladder tumours. The cells formed tumour nodules, with a similar structure, when transplanted into hamster cheek pouches. There is a stem line chromosome number of 48. Karyotypes of 60% of the stem line cells had one extra chromosome in Group C and one in Group D.

DNA and chromosomes

Abstract: DNA forms a Double Helix shape DNA is arranged in a double helix shape. The up rights of the “ladder” consist of alternating sugar and phosphate molecules bonded together. Making up the “rungs” are two base molecules bonded to each other. A nucleotide is one unit of DNA. DNA (deoxyribonucleic acid) is made from smaller repeating units called nucleotides, which consist of a sugar, a triphosphate and a base.

Chromosome constitution and its bearing on the chromosomal radiosensitivity in man

Abstract: Blood samples obtained from patients with various types of inborn chromosome abnormalities were exposed to γ-rays and the relationship between the chromosome constitution and chromosomal radiosensitivity of lymphocytes was studied by analysing types and frequencies of radiation-induced chromosome aberrations. The results showed that the chromosomal radiosensitivity was consistently higher in the cells which were trisomic for the whole or a part of a chromosome than in the cells with normal karyotype, but it was not significantly influenced by the monosomic conditions, reciprocal translocation and inversion. Age of the subjects also affected the chromosomal radiosensitivity, which was elevated in the neonates. The analysis of chromosome aberrations showed that the high frequency of radiation-induced chromosome aberrations was due to the increased production of exchange aberrations and that the level of deletions was not affected either by factors of the chromosome constitution or of the age of the subject. A hypothesis to explain the increased chromosomal radiosensitivity of the trisomic cells was given in line with the effects of altered enzyme activity on the production of exchange aberrations. The parallelism between the increased chromosomal radiosensitivity in the trisomic cells and the susceptibility of the affected persons to neoplasia allowed us to recognize that the trisomic cells are particularly cancer-prone and that the illegitimate repair of chromosome damage, which is intrinsic to the trisomic cells, may play an important role in the development of cancer.

Unusual sex chromosome inheritance in mammals.

Abstract: The male has proven to be the heterogametic sex in all mammals studied so far. As is well known, the males usually have the sex chromosomes XY and the females XX. In recent years, however, many exceptions from this general pattern have been discovered. With our present knowledge, the different sex chromosome mechanisms in mammals may be divided into five main groups, and the first of them into subgroups, as follows: (i) Species with XX/XY sex chromosomes: (a) X of original size (see below), Y small; (b) X large, Y small; (c) X large, Y large: (i) end-to-end association of X and Y at male meiosis, (ii) chiasma between X and Y at male meiosis. (ii) Species with XX/XY1Y2 sex chromosomes. (iii) Species with X1X1X2X2/X1X2Y sex chromosomes. (iv) Species with complicated or unknown mechanisms for sex determination. (v) Species with mosaicism of the sex chromosomes, but apparently with an XX/XY mechanism for sex determination. The present contribution will mainly deal with unusual sex chromosome inheritance, that is the groups (ii), (iii) and (iv) above, but the other two groups will also be briefly discussed and examples will be given. Recently Raicu, Kirillova & Hamar (1969) described a new sex chromosome mechanism ( X1X1X2X2/X1X2Y1Y2) in the vole Microtus arvalis , but this observation was not confirmed by Schmid (1969), who found an ordinary XX/XY mechanism with both X and Y readily identifiable and of ‘normal’ size, the X comprising 5.6% of ( n A + X) and Y being the smallest chromosome of the complement. Late DNA replication was demonstrated in the allocyclic X and in the Y. Also Wolf (1969) found normal sex chromosomes in this species with no multivalents at male meiosis.

The chromosomes of the order Crocodilia

Abstract: The somatic karyotypes of the 21 surviving species of the order Crocodilia are presented. The population surveyed totals 71 animals, with representatives of both sexes in 13 species. No karyotypic dif

A comparative chromosome study of the North American species of sticklebacks (Teleostei: Gasterosteidae).

Abstract: The five North American species of the stickleback family Gasterosteidae were studied karyologically. They constitute two diploid-count groups; one with 46 includes Λpeltes quadracus

Cytological evidence on the origin of sweet potato.

Abstract: The results of intensive meiotic studies, particularly of the karyology and chromosomal homology at the pachytene stage, in the sweet potato (Ipomoea batatas L.), which is a hexaploid (2 n = 90), have thrown considerable light on its origin and genome relationships. Using suitable criteria, such as relative length of chromosomes, centromere position, chromomere pattern, absence of light staining segments in one of the arms, presence of telochromomere etc., 40 of the 45 haploid chromosome complement at pachytene were identified and assigned to 19 chromosomal types. Among these types, eight were present singly; in six of the types, chromosomes were present in duplicate, and in two types, in triplicate. The occurrence of higher multivalent chromosomal associations such as hexavalents and pentavalents, in addition to the quadrivalents already reported, was recorded for the first time at the pachytene and metaphase I stages. The hexavalents at pachytene were resolved into three distinct types based on the morphology of the participating chromosomes. A maximum number of nine quadrivalents at the metaphase I stage and four in the incompletely analyzed pachytene nuclei were recorded. The constituent chromosomes of three of the quadrivalents at pachytene stage were identified. From these observations, it is suggested that (i) the three parental genomes are partly homologous (ii) two of the genomes show closer homology to one another than to the third and (iii) the three genomes differ with respect to one or more of the eight chromosomal types occurring singly. The available information rules out an autopolyploid origin for sweet potato and suggests that the parental genomes are from closely related taxa. The advantages are emphasized of pursuing similar studies in other American Ipomoea species to unravel their relationship with the sweet potato. Among other meiotic irregularities, a translocated chromosome and a chromosome carrying inversion were detected at the pachytene stage and the possible role they may play in varietal differentiation is discussed.

Chromosome number, structure and autosomal polymorphism in the marine mussels mytilus edulis and mytilus californianus

Abstract: The bay mussel Mytilus edulis (Linnaeus) and the California sea mussel Mytilus californianus (Conrad) have a common diploid chromosome number 28 (n = 14) that is, there were 14 bivalents during meiosis and 28 chromosomes during mitosis. A total of 35 specimens of the two species were examined from several intertidal locations in Puget Sound and the Northwest Pacific coast of the United States. The number of meiotic bivalents in stripped or spawned eggs was always constant but aneuploid counts of mitotic chromosomes were made in cleaving eggs and embryos. Heteromorphic bivalents in meiotic plates and heteromorphic homologues in mitotic karyotypes were observed. The number of metacentric, submetacentric and acrocentric chromosomes was variable. There were 2 to 6 pairs of acrocentrics in different complements. This polymorphism indicates the existence of pericentric inversions or centric-shifts in both meiotic and mitotic chromosomes.

Chromosome abnormalities in early spontaneous abortions.

Abstract: The reports in 1959 of the chromosomal anomalies in Turner's, Klinefelter's, and Down's syndromes were followed by a period of rapid advancement in human medical cytogenetics. Clinical cytogenetic research continued on living subjects, while a large area of human development remained relatively uncommitted to study. This area, spontaneous abortion, results in foetal wastage estimated at 10% of recognized pregnancies (Potter and Adair, 1963) or up to 20% of all conceptions. The Geneva Conference (1966) concluded that chromosomal abnormalities were a significant factor in spontaneous abortions, since 190% of nearly 800 abortuses were found to have a chromosome anomaly. In clinical patients a variety of chromosomal rearrangements and mosaicism is found. Theoretically even larger numbers of chromosomal aberrations would be predicted and expected to be found in spontaneous abortions. However, there have been little or no reports of abnormalities such as monosomy, deletion, duplication, translocation, and ring in abortions. A study on the cytogenetics of spontaneous abortions was initiated in 1964 at the Kapiolani Maternity and Gynecological Hospital in Honolulu. The findings on the abnormal chromosome constitution of the abortuses are presented in this report.

Absent IgA and deletions of chromosome 18.

Abstract: Since extra chromosomal material in humans was first described by Lejeune, Turpin, and Gautier (1959) in association with Down's syndrome, patients with trisomic and partial monosomic conditions have been studied in an attempt to locate specific genetic loci upon specific chromosomes. An individual with a deletion of part of an autosome is hemizygous for genes on the homologue of the deleted fragment. As a result, recessive genes may be uncovered which, in the absence of a deletion, may have been masked by their dominant alleles. This type of 'deletion mapping' may be important in locating genes on autosomes. We here present studies on 4 patients with deletions involving chromosome 18 and discuss the possible relation between this chromosomal aberration and the locus for immunoglobulin A (IgA). Wang et al. (1962) described a boy with multiple congenital anomalies including atretic ear canals, with secondary deafness and mental retardation. Chromosomal analysis revealed a ring 18 chromosome (18r)t in all cells counted. This was the first reported case of a deletion of a portion of chromosome 18. There have been numerous subsequent reports of similar deletions, both as rings (Grouchy, 1965; Genest, Leclerc, and Auger, 1963; Gripenberg, 1967; Gropp, Jussen, and Ofteringer, 1964; Jeune et al., 1967; Lucas et al., 1963; Mikelsaar, Talvik, and Sitska, 1967; Palmer, Fareed, and Merritt, 1967) and as partial deletions of the long arm of chromosome 18 (18q -) (Day et al., 1967; Grouchy, 1965; Insley, 1967; Law and Masterson, 1966; Nance et al., 1968; Wertelecki, Schindler, and Gerald, 1966; Wolf et al., 1967).

Xg locus: failure to detect inactivation in females with chronic myelocytic leukaemia.

Abstract: THE inactive-X hypothesis states that only one of the two X chromosomes in each somatic cell of adult mammalian females is genetically active. The initial event in early embryogenesis which determines whether the paternal or the maternal X chromosome will remain active in any given cell is presumably random; once made, the choice is fixed for that cell and for all its descendants1–4. Although this type of inactivation has been demonstrated in man for a number of X-linked loci5, it is not known whether the entire X chromosome is inactivated.

Late DNA replication in male mouse meiotic chromosomes.

Abstract: Parts of the male mouse meiotic complement comprising the Y chromosome, the whole X chromosome, and near-centromeric parts of autosomal bivalents are synthesized late, as judged by tritiated thymidine autoradiography. This confirms the occurrence of end-to-end association between X and Y chromosomes and suggests that paired heterochromatic segments in autosomes must synthesize DNA at the same time.

A protein electrophoretic study of three amphiploids and eight species in avena

Abstract: Seed proteins of three synthetic amphiploids, one autotetraploid and eight species that include representatives of all ploidy levels and karyotypes of Avena were studied by acrylamide gel electroph...

Chromosomal abnormalities in ataxia-telangiectasia (Louis Bar's syndrome).

Abstract: The chromosomes in lymphocytes of 6 children with ataxia-telangiectasia have been studied. In 2 patients cell populations marked by abnormal chromosomes were found. Cytogenetic findings and IgA seem not to be strongly related.

The amounts of nuclear DNA and the duration of DNA synthetic period (S) in related diploid and autotetraploid species of oats.

Abstract: The relative amounts of nuclear DNA of root meristematic cells of two related diploid Avena species, A. strigosa 2x and A. pilosa, which have different karyotypes, and an autotetraploid of one, A. strigosa 4x, were measured by Feulgen microspectrophotometry. The durations of various periods of their mitotic cycles were studied by autoradiography of cells pulse-labeled with tritiated thymidine. The results show that the autotetraploid, with twice the amount of nuclear DNA of its diploid, has the same duration of S period as the diploid, while A. pilosa, with intermediate nuclear DNA content, has a longer S period. These results support the hypothesis that homologous chromosomes or genomes require similar duration for their DNA synthesis and suggest that the structures of chromosomes are involved in temporal control of the DNA synthesis in cells.

A Special Role of the Group 17,18 Chromosomes in Reticuloendothelial Neoplasia

Abstract: The hypothesis is advanced that abnormalities of the chromosome group 17,18 play a special role in the genesis and/or evolution of some reticuloendothelial neoplasms. Aberrations of the group 17,18 chromosomes in tumour cells exceed in variety the reported anomaliesof any other chromosome. Both the frequency of these aberrations and their nature make them most unlikely to be due to chance. They appear to be non-random, often occurring in every cell of a tumour, and like the Ph1 anomaly in chronic granulocytic leukaemia, mightpossess aetiological significance. The Ep- and Eqchromosomal anomalies resemble the Ph1 in being fine structural modifications, which occur as acquired lesions only in neoplasms, often in tumour cells with otherwise normal karyotypes. Aberration of the group 17,18 chromosomes may sometimes be secondary to neoplasia but nevertheless of evolutionary significance for the tumour cells. Changes leading to relative or absolute excess of long-arm material of chromosome 18 may confer survival advantage upon cells, particularly if a normal complement of short-arm material is simultaneously retained. However, specific deletion of the distal part of the long arms of No. 18 may also favour cell survival. The short arms of chromosome 18 may carry genes limiting cell reproduction, while the long arms carry material promoting proliferation. More distally on the long arms, there may be genes which also limit reproduction. Disturbances affecting the balance between these components of the genome may be important in inception of neoplasia or subsequent evolution of tumour cell lines.

The Christchurch chromosome (Gp-). Mongolism, erythroleukemia and an inherited Gp- chromosome (Christchurch).

Abstract: An 18-month-old male infant with mongolism and erythremic myelosis had two cell lines in his bone marrow and peripheral blood: one cell line, with 47 chromosomes, had 2 Gp— chromosomes, and the other, with 51 chromosomes, had 3 Gp—chromosomes. He died of acute myeloblastic leukemia at 21 months of age. The Gp— chromosome was present in four generations of his family; his mother, his maternal grandmother and his maternal maternal great-grandmother were carriers and phenotypically normal. The Gp— chromosome has not previously been reported in a patient with erythremic myelosis, an uncommon disease in children. Review of all reported propositi and members of their families with the Gp— chromosome shows no consistent phenotypic effect of this deletion. However, among 37 progeny of 18 carriers of the Gp— chromosome, five have had mongolism with 47 chromosomes. The Gp— chromosome itself appears to segregate normally among the progeny of carriers.

Wolf-Hirschhorn syndrome associated with an unusual abnormality of chromosome no. 4.

Abstract: A clinically recognizable syndrome associated with deletion of the short arms of chromosome B4 was first reported by Wolf et al. (1965) and Hirschhorn, Cooper, and Firschein (1965). Twelve patients have been reported (Leao et al., 1967; Carter, Baker, and Hayman, 1969; Giorgi, Ceccarelli, and Paci, 1965; Hijmans and Shearin, 1965; Hirschhorn et al., 1965; Miller et al., 1966a, b; Pfeiffer, 1968; Sidbury, Schmickel, and Gray, 1964; Taylor, 1968; Wolf et al., 1965), including three who were thought to represent an atypical 'cri du chat' syndrome (Giorgi et al., 1965; Hijmans and Shearin, 1965; Sidbury et al., 1964). Though the syndrome shows similarity to 'cri-du-chat', there are important differences in a number of the phenotypic characteristics, such as the midline cranial defects and the lack of a cat-cry. In addition, autoradiography studies in six cases (Leao et al., 1967; Miller et al., 1966a, b; Pfeiffer, 1968; Wolf et al., 1965) have shown that the Wolf-Hirschhorn syndrome is associated with deletion of the short arms of chromosome No. 4; whereas, in 'cri-duchat' the short arms of No. 5 are deleted. Our patient shows the phenotype associated with deletion of the short arms of chromosome No. 4; however, the karyotype from this patient shows elongated short arms of chromosome No. 4. This structural abnormality has not been previously described in this syndrome; nor to our knowledge has a similar abnormal chromosome No. 5 been found in 'cri-du-chat'. Assuming that the WolfHirschhorn phenotype is a deletion syndrome, we postulate that the deletion of the abnormal chromosome No. 4 may be masked by translocation chro-

Effects of adenoviruses on the chromosomes of normal human cells and cells trisomic for an E chromosome.

Abstract: NON-RANDOM damage to the chromosomes of human embryo kidney (HEK) cells by adenovirus type 12 (in vitro) has been reported by Zur Hausen1 We have obtained similar results with adenovirus type 12 in fibroblasts grown from human embryo lung (HEL) and from skin biopsy samples, as well as in the epithelial HEK cells