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Reciprocal translocations produce imbalances by three types of disjunction which are, in decreasing frequency, adjacent 1, 3:1, and adjacent 2. Adjacent 1 disjunction produces duplication deficiencies of inverse topography to those of adjacent 2. The imbalanced chromosome segments in one of these types are balanced in the other. The disjunction 3:1 produces pure trisomies and monosomies. The following situations predispose to adjacent 2 disjunction: translocations between the long arms of two acrocentric chromosomes or between one of these and that of a No 9 chromosome; centric segments, either short or carrying a heterochromatic zone (9qh); a balanced translocation in the mother. The factors predisposing to the disjunction adjacent 2 operate by selection, or directly on the meiotic configuration. Some of them (shortness of the interstitial segment, shortness of the short arms of translocation chromosomes) act in both these ways. Their influence is probably responsible for the repetitive and exclusive character of this disjunction. The conditions for the occurrence of the 3:1 disjunctions seem less strict than those for adjacent 2, although they should be of the same nature (involvement of acrocentrics or a chromosome 9 in the translocation, maternal origin). [ABSTRACT FROM PUBLISHER]

Five members of a family with a balanced insertion (1;5)(q32;q11q22) are presented. The daughter of one of them shows multiple malformations and a partial trisomy for the long arms of chromosome No. 5 (5q11 to 5q22 segment) resulting from a 'aneusomie de recombinaison' in her mother. The propositus' karyotype is 46,XX,rec(1;5)ins (1;5)(q32;q11q22). This case is the first reported example of an insertion between two chromosomes followed by 'aneusomie de recombinaison'. It also is the first reported case of trisomy invovling the long arms of chromosome No. 5. [ABSTRACT FROM PUBLISHER]

A local study carried out in the Medical School of Grenoble shows that teaching in the first year in medicine studies satisfies neither the students, nor the teachers. The Faculty of Medicine of Grenoble decided to set up a reform in order to offer a high quality education. This reform leads to a complete reorganization of the curriculum and to the intensive use of new information and communication technologies of information, in particular, the use of multimedia documents. The communication and information technologies team of the Faculty of Medicine of Grenoble carried out an innovating and daring reform to start at the academic year 2006-2007. The new course is built on three activities: self learning on multi-media resources, meetings with teachers for questions-answers sessions and tutorials animated by older students. This article reports the first results for this successful project. In the academic year 2006-2007, are concerned 1290 students, 40 teachers and 8 disciplines.

Purpose: Lymphomas and testicular cancers are the most frequent malignancies among young men. With recent improvement of survival rates, for many patients, the question is raised of the consequences of the anticancer treatments on their fertility and more specifically of a potential genetic risk for the offspring. This article presents the study of sperm aneuploidy rates in the largest population of cancer-treated patients studied thus far., Experimental Design: In the present study, 38 patients were initially included 7 months to 5 years after a cancer treatment by chemotherapy and/or radiotherapy for testicular cancer (n = 19) or lymphoma (n = 19). Twelve of them were azoospermic. Sperm aneuploidy rates of chromosomes X, Y, 13, 18, and 21 were analyzed by multicolor fluorescent in situ hybridization in the 26 other patients., Results: In most cases, the disomy/diploidy rates after cancer therapy did not significantly differ from those observed in the group of control healthy donors. Only five patients (one lymphoma and four testicular cancer) showed significant but still moderate increases in disomic and/or diploid sperm. For the lymphoma patient, the short posttherapeutic delay after the treatment could explain the elevated aneuploidy rates, whereas no risk factor in the clinical, biological, or therapeutic records could be identified in any of the four testicular cancer patients with elevated sperm aneuploidy rates., Conclusions: These data suggest an absence of long-term effect of anticancer therapy on sperm aneuploidy rates, and therefore, no long-term increased risk of aneuploidy for the offspring obtained either spontaneously or after assisted reproductive techniques.

Meiotic segregation of sex chromosomes from two fertile 47,XYY men was analysed by a three-colour fluorescence in situ hybridisation procedure. This method allows the identification of hyperhaploidies (spermatozoa with 24 chromosomes) and diploidies (spermatozoa with 46 chromosomes), and their meiotic origin (meiosis I or II). Alpha-satellite probes specific for chromosomes X, Y and 1 were observed simultaneously in 35,142 sperm nuclei. For both 47,XYY men (24,315 sperm nuclei analysed from one male and 10,827 from the other one) the sex ratio differs from the expected 1:1 ratio (P < 0.001). The rates of disomic Y, diploid YY and diploid XY spermatozoa were increased for both 47,XYY men compared with control sperm (142,050 sperm nuclei analysed from five control men), whereas the rates of hyperhaploidy XY, disomy X and disomy 1 were not significantly different from those of control sperm. These results support the hypothesis that the extra Y chromosome is lost before meiosis with a proliferative advantage of the resulting 46,XY germ cells. Our observations also suggest that a few primary spermatocytes with two Y chromosomes are able to progress through meiosis and to produce Y-bearing sperm cells. A theoretical pairing of the three gonosomes in primary spermatocytes with an extra sex chromosome, compatible with active spermatogenesis, is proposed.

Three cases of Fanconi's anemia are described in three siblings. Cytogenetic studies disclose increase of chromosomal structural anomalies (unclassifiable rearrangements, quadriradials, dicentrics) and suggest in the parents an increase in chromatid-type abnormalities. Further, the mother carries a 46,XX/47, XXX/48, XXXX mosaic and other kinds of aneuploidy. All enzymatic activities in erythrocytes (aerobic and anaerobic glycolysis) in the three children are high (even that of hexokinase), except pyruvate-kinase. These results are reminiscent of those found in other types of bone marrow dysfunctions. An uncomplete investigation of enzymes in leucocytes and platelets discloses activities within normal limits.

Structural chromosome anomalies (1 477 cells examined) and sister chromatid exchanges after two replication cycles with BrdU (771 cells studied) were evaluated in 12 patients with diffuse scleroderma and having received no recent or important irradiation. The increase of structural anomalies, chromatidic as well as chromosomal, is always low, inconstant and cannot be considered as having a diagnostic value. Increase of sister chromatid exchanges could be a more sensitive method of investigation. In particular, it is not influenced by low doses of diagnostic X-rays.

A duplication 10q22q25 was studied in the fetus of a mother carrier of a t(14q21q). On this occasion, duplications reported in the literature are reviewed. Chromosomal rearrangements involving two breaks always result in tandem duplications, while three break- rearrangements result in tandem or mirror adjacent duplications, or in non adjacent direct or inverted duplications, or in direct or inverted autointerstitial duplications.

A study of 100 sperm karyotypes from 8 normal subjects was carried out using the technique of in vitro hetero-specific human-hamster fertilisation. 19 of those showed some abnormality. 17% of those were hyperploidies or hypoploidies and 2% showed structural abnormalities. A study carried out at the same time on 34 hamster egg karyotypes showed 6 hypoploidies and 1 hyperploidy. In effect oa cytogenetic technique which is very similar to this one makes it possible to analyse the human oocyte karyotype. The results found in these samples of motile sperms show a higher incidence of abnormality than in other published series, but these figures can not be extrapolated to the composition of in vivo whole sperms.

The mutagenecity of trichloroethylene and its metabolites (trichloroethanol and chloral hydrate) have been tested by using the method of sister chromatide exchanges (SCE). We have found the increasing SCE in workers chronically exposed to trichloroethylene. The increasing of SCE was also observed when the human lymphocytes were exposed to trichloroethanol and chloral hydrate in vitro in certain concentrations. The all results of tests groups are compared with those of the control groups and the difference is statistically significant.

The karyotype of 443 infertile males has been studied (infertility of unknown etiology). The sample has been divided in 3 groups according to the data of their spermogram: Gr 1--101 males with a normal spermogramm (selected through the sterility of their couple). Gr 2--185 infertile males with oligospermy (less than 20 millions spermatozoal/ml). Gr 3--157 infertile males with azoospermia. This study shows: --No significant difference in chromosomal aberration rate between group 1 and general male population. --A rate of 5% chromosomal aberration in group 2 (versus 0.7% in normal male population p less than or equal to 10(-8], nearly exclusively balanced translocations. --A rate of 21% chromosomal aberration in group 3, nearly exclusively 47, XXY or 46, XX (p less than or equal to -9). The karyotype is unlikely to bring any information in infertile males with normal spermogram; on the contrary it is of valuable interest in infertile males with abnormal sperm.

The levels of zinc, ultrafilterable (UF) zinc, copper and manganese in normal and pathological (astheno-, azoo-, oligospermic) seminal plasma were measured by flameless atomic absorption. For ultrafiltrable zinc, a special method was used to treat Amikon membranes. A lower ultrafiltrable zinc level was found in azoospermic and a lower manganese level in oligospermic seminal plasma. At this time the meaning of these results is unknown.

A comparative study of five observations of a r (20) syndrome characterized by facial dysmorphism, the absence of severe malformations, and rather late onset of encephalopathy and seizures.

Structural chromosome anomalies (1 477 cells examined) and sister chromatid exchanges after two replication cycles with BrdU (771 cells studied) were evaluated in 12 patients with diffuse scleroderma and having received no recent or important irradiation. The increase of structural anomalies, chromatidic as well as chromosomal, is always low, inconstant and cannot be considered as having a diagnostic value. Increase of sister chromatid exchanges could be a more sensitive method of investigation. In particular, it is not influenced by low doses of diagnostic X-rays.

One of the children of a t(15;22) (q111;p11) woman has lost the minute metacentric der(15) without any clinical consequence, indicating the inocuity of the 15pter----q111 and 22pter----p11 monosomies. The segregation mechanism of this monosomy and, from this family, the relation between reciprocal translocations and Robertsonian translocations are discussed. Another subject with r(22) in the same family questions on an hypothetic common origin.

Cytogenetic study of a case of Bloom's syndrome (number 46 of the international registry) confirms the excess of exchanges in all cellular types with the exception of a minority of lymphocytes and of two lymphoblastoid cell lines. These exchanges are produced in an X or U fashion between sister chromatids or between homologous chromatids and produce both simple and complex figures for which symmetry is the common feature. Some of these structures are rearranged secondarily, producing centric or acentric fragments and marker chromosomes. Triradial configurations are considered to be the result of exchanges rather than of partial endoreduplication. Chromatid and chromosome breaks are interpreted to result from incomplete exchanges. It is suggested that the general propensity for exchanges is the primary event responsible directly or indirectly for the cytogenetic observations rather than a defect in one of the DNA-repair mechanisms. No increase in mitomycin C sensitivity appears in vitro. The excess of SCEs is partially correlated by contact in vitro with normal cells and to a lesser degree by the culture medium in which the cells were grown.

Artificial insemination with donors has genetic repercussions which increase with its impact on demography. Genetic control of semen donors offers a possibility of preventing the main genetic handicaps. The French Federation of Human Semen Study and Preservation Centres (CECOS) is currently organizing such a control system. The reasons for this and the modalities of the system are given in this article.

Sperm cytogenetics was carried out using technique of in vitro heterospecific human-hamster fertilization. Sperm of 4 men heterozygous from 4 reciprocal translocations (t(4; 17), t(5; 13), t(6; 7) and t(9; 18] was studied. Segregations were various but a majority of unbalanced complements resulting from adjacent 1 segregations was observed. This prevalence was stronger when the pachytene diagram predisposed the translocation to this mode of imbalance at term.

An r(14) is observed in monozygotic twins, with psychomotor retardation and no obvious somatic malformation.

A new example of ring-6 chromosome is reported in a 5-year-old girl with psychomotor and growth retardation, microcephally, and microphtalmia. The breakpoints are considered to be distal on both arms of chromosome 6, in view of apparently normal transmission of HLA phenotypes.