Link Between Increased Prevalence of Autism Spectrum Disorder Syndromes and Oxidative Stress, DNA Methylation, and Imprinting

n/

De novo complex intra chromosomal rearrangement after ICSI: characterisation by BACs micro array-CGH

<p>Abstract</p> <p>Background</p> <p>In routine Assisted Reproductive Technology (ART) men with severe oligozoospermia or azoospermia should be informed about the risk of de novo congenital or chromosomal abnormalities in ICSI program. Also the benefits of preimplantation or prenatal genetic diagnosis practice need to be explained to the couple.</p> <p>Methods</p> <p>From a routine ICSI attempt, using ejaculated sperm from male with severe oligozoospermia and having normal karyotype, a 30 years old pregnant woman was referred to prenatal diagnosis in the 17^thweek for bichorionic biamniotic twin gestation. Amniocentesis was performed because of the detection of an increased foetal nuchal translucency for one of the fetus by the sonographic examination during the 12^thweek of gestation (WG). Chromosome and DNA studies of the fetus were realized on cultured amniocytes</p> <p>Results</p> <p>Conventional, molecular cytogenetic and microarray CGH experiments allowed us to conclude that the fetus had a <it>de novo </it>pericentromeric inversion associated with a duplication of the 9p22.1-p24 chromosomal region, 46,XY,invdup(9)(p22.1p24) [arrCGH 9p22.1p24 (RP11-130C19 → RP11-87O1)x3]. As containing the critical 9p22 region, our case is in coincidence with the general phenotype features of the partial trisomy 9p syndrome with major growth retardation, microcephaly and microretrognathia.</p> <p>Conclusion</p> <p>This de novo complex chromosome rearrangement illustrates the possible risk of chromosome or gene defects in ICSI program and the contribution of array-CGH for mapping rapidly de novo chromosomal imbalance.</p

Biochemical Hazards during Three Phases of Assisted Reproductive Technology: Repercussions Associated with Epigenesis and Imprinting

Medically assisted reproduction, now considered a routine, successful treatment for infertility worldwide, has produced at least 8 million live births. However, a growing body of evidence is pointing toward an increased incidence of epigenetic/imprinting disorders in the offspring, raising concern that the techniques involved may have an impact on crucial stages of early embryo and fetal development highly vulnerable to epigenetic influence. In this paper, the key role of methylation processes in epigenesis, namely the essential biochemical/metabolic pathways involving folates and one-carbon cycles necessary for correct DNA/histone methylation, is discussed. Furthermore, potential contributors to epigenetics dysregulation during the three phases of assisted reproduction: preparation for and controlled ovarian hyperstimulation (COH); methylation processes during the preimplantation embryo culture stages; the effects of unmetabolized folic acid (UMFA) during embryogenesis on imprinting methyl &ldquo;tags&rdquo;, are described. Advances in technology have opened a window into developmental processes that were previously inaccessible to research: it is now clear that ART procedures have the potential to influence DNA methylation in embryonic and fetal life, with an impact on health and disease risk in future generations. Critical re-evaluation of protocols and procedures is now an urgent priority, with a focus on interventions targeted toward improving ART procedures, with special attention to in vitro culture protocols and the effects of excessive folic acid intake

Mise en évidence de quelques enzymes dans le sperme de la carpe (Cyprinus carpio L.) et de la truite (Salmo gairdnerii Richardson) et dans le liquide coélomique de la truite

L'utilisation de la méthode Auxotab a permis la mise en évidence semi-quantitative de 16 enzymes dans les spermes de la Carpe et de la Truite, ainsi que dans le liquide cœlomique de la Truite. Il existe des différences d'équipement enzymatique sensibles entre le sperme total, le liquide séminal et les spermatozoïdes isolés ; elles portent essentiellement sur les phosphatases. Deux liquides cœlomiques dont l'activité biologique sur l'ovulation in vitro était connue, ont pu être différenciés par l'apparition d'une activité trypsique

DNA Methylation Patterns in the Early Human Embryo and the Epigenetic/Imprinting Problems: A Plea for a More Careful Approach to Human Assisted Reproductive Technology (ART)

An increasing number of publications indicate that babies born after IVF (in vitro fertilization) procedures have higher rates of anomalies related to imprinting/epigenetic changes, which may be attributed to suboptimal culture conditions. Appropriate maintenance of DNA methylation during the first few days of an in vitro culture requires a supply of methyl donors, which are lacking in current in vitro culture systems. The absence of protection against oxidative stress in the culture increases the risks for errors in methylation. A decrease in the methylation processes is sometimes observed immediately post fertilization, due to delays that occur during the maternal&ndash;zygotic transition period. Care should be exercised in ART (assisted reproductive technology) procedures in order to avoid the risk of generating errors in methylation during the in vitro culture period immediately post fertilization, which has an impact on imprinting/epigenetics. Formulation of IVF culture media needs to be re-assessed in the perspective of current knowledge regarding embryo physiology

Sur la composition en acides aminés libres et peptidiques du liquide séminal de carpe (Cyprinus carpio)

Free and peptidic amino acids were measured in the seminal plasma of carp. Some acids such as glutamic acid and glutamine, taurine, glycine and proline were exceptionally abundant, while others like lysine, arginine and histidine were found in small amounts. Generally, the amino acid level was higher in carp seminal plasma than in that of other Vertebrate species. As this level was systematically higher than in the blood plasma, it is supposed that there was neoformation of an original fluid in the genital tract

Sur la composition en acides aminés libres et peptidiques du liquide séminal de carpe (Cyprinus carpio)

Free and peptidic amino acids were measured in the seminal plasma of carp. Some acids such as glutamic acid and glutamine, taurine, glycine and proline were exceptionally abundant, while others like lysine, arginine and histidine were found in small amounts. Generally, the amino acid level was higher in carp seminal plasma than in that of other Vertebrate species. As this level was systematically higher than in the blood plasma, it is supposed that there was neoformation of an original fluid in the genital tract