Listing 1 - 10 of 23 | << page >> |
Sort by
|
Choose an application
Choose an application
Choose an application
AFR Africa --- Hymenophyllaceae --- aneuploidy
Choose an application
Choose an application
Choose an application
Aneuploidy means any karyotype that is not euploid, anything that stands outside the norm. Two particular characteristics make the research of aneuploidy challenging. First, it is often hard to distinguish what is a cause and what is a consequence. Secondly, aneuploidy is often associated with a persistent defect in maintenance of genome stability. Thus, working with aneuploid, unstable cells means analyzing an ever changing creature and capturing the features that persist. In the book Aneuploidy in Health and Disease we summarize the recent advances in understanding the causes and consequences of aneuploidy and its link to human pathologies.
Choose an application
Spontaneous abortion is a common event in the reproductive population, occuring in at least 15% of recognized pregnancies. The advent of cytogenetic techniques allows us to explore the chromosomal constitution of tissue samples collected from dismissed products of conception. It is now well established that chromosomal abnormalities account for at least 50% of pregnancy losses occurring before the 20th week of gestation. Pointing out that human reproduction is terribly inefficient but remarkably counterbalanced by a natural selection of products of conception. In this work, we collected data from the Center of Medical Genetics (UCL), in Brussels. Altogether, during a period of 4 years, 523 cases of spontaneous abortions before the 22th week after the last menstrual period were analyzed by the conventionnal method of karyotype. The first part of this work describes the chromosomal results found in these samples, and compared them on basis of maternal and gestationnal age. On the other hand, as we know that increased maternal age is the major risk factor for chromosomal abnormalities and that during the past decades mean maternal age at birth never stopped increasing, this work paid particular attention to the effect of maternal age on the chromosomal constitution of abortuses La fausse couche est un évènement très fréquent dans la population reproductive, se produisant dans approximativement 15% des grossesses cliniquement reconnues. L’avènement des techniques cytogénétiques permet l’exploration de la constitution chromosomique des échantillons de tissus collectés à partir des produits de conception issus de fausses couches. Il est maintenant bien établi que les anomalies chromosomiques sont la cause d’au moins 50% des fausses couches se produisant avant la 20ème semaine de gestation. Ce qui nous montre que la reproduction humaine est très incompétente mais remarquablement compensée par une sélection naturelle des produits de conception. Dans ce travail, nous avons collecté les données du Centre de Génétique Médicale de l’UCL à Bruxelles. Sur une période de 4 ans, 523 cas de fausses couches ayant eu lieu avant la 22ème semaine après les dernières règles ont été analysées selon la méthode classique du caryotype. La première partie de ce travail décrit les résultats quant à la composition chromosomique de ces échantillons, et les compare sur base de l’âge maternel et de l’âge gestationnel. D’autre part, comme nous savons que l’âge maternel constitue le principal facteur de risque pour la survenue d’anomalies chromosomiques et que durant les dernières décennies, l’âge maternel à la naissance n’a cessé d’augmenter, ce travail s’intéresse particulièrement à l’effet de l’âge maternel sur la composition chromosomique des produits de fausses couches
Abortion, Spontaneous --- Chromosomes --- Aneuploidy --- Polyploidy
Choose an application
Aneuploidy --- Congresses --- Chromosome numbers --- Congresses. --- Conferences - Meetings --- Aneuploidy - Congresses --- Aneuploidy - congresses
Choose an application
Aneuploidy --- Cytogenetics --- Cytology --- Genetics --- Chromosome numbers
Choose an application
Aneuploidy --- Chromosome mapping --- Down syndrome --- Phenotype --- Aneuploidy --- Chromosome mapping --- Down syndrome --- Phenotype
Listing 1 - 10 of 23 | << page >> |
Sort by
|