View clinical trials related to Chromosome Abnormality.
Filter by:The project is focused on the detailed study of structural genomic variants (SVs). Such genetic mutations are in fact alterations in the DNA molecule structure and include copy number variants, inversions and translocations. A single event may affect many genes as well as regulatory regions and the specific phenotypic consequences will depend on the location, genetic content and type of SV. Many times, the specific disease-causing mechanism is not known. Here, we plan to study the molecular genetic behavior of structural variants as well as the underlying mutational mechanisms involved. First, we will use genome sequencing to pinpoint the chromosomal breakpoints at the nucleotide level, characterize the genomic architecture at the breakpoints and study the relationship between structural variants and SNVs. Second, we will study how structural variants impact gene expression. Finally, we will functionally explore the disease mechanisms in vivo using zebrafish and in vitro using primary patient cells and induced pluripotent stem cells. Our studies will focus on the origin, structure and impact of structural variation on human disease. The results will directly lead to a higher mutation detection rate in genetic diagnostics. Through a better understanding of disease mechanisms our findings will also assist in the development of novel biomarkers and therapeutic strategies for patients with rare genetic disorders.
This is a phase II, open-label, prospective study of T cell receptor alpha/beta depletion (α/β TCD) peripheral blood stem cell (PBSC) transplantation for children and adults with hematological malignancies
This is a prospective randomised study of the evaluation of the clinical IVF results after invasive PGT-A embryo selection versus Non-invasive PGT-A assisted embryo selection in subfertile women.
This is a prospective randomised study of the evaluation of the clinical IVF results after time lapse assisted embryo selection versus Non-invasive PGT-A assisted embryo selection in subfertile women.
Myelodysplastic syndromes (MDS) are chronic myeloid hemopathies characterized by ineffective hematopoiesis (with peripheral cytopenias) and which contrast with a marrow of normal richness. MDS is considered one of the four most common blood diseases. The incidence is estimated at 4,059 cases / year in 2012 with an average age of 78 years in men and 81 years in women (INCA report, Cancers in France in 2015). The incidence increases with lengthening of the lifespan. The main risk of MDS is transformation to acute leukemia in 30 to 40% of cases. Treatment options depend on clinical, hematologic and chromosomal abnormalities. The prognosis is considered to be at low or high risk of developing acute leukemia. This distinction will therefore have an impact on the therapeutic solution (s). MDS exhibit clinical, morphological and genetic heterogeneity. It is therefore necessary to form subgroups of patients to better understand the physiopathogenesis of this pathology. The constitution of a biocollection will make it possible to search for clinical and biological prognostic markers in order to identify patients progressing to acute myeloid leukemia.
The objective of this study is to explore whether non-invasive chromosome screening (NICS) can be used as an effective indicator for embryos selection besides morphology through a multicenter randomized controlled trial, by comparing the differences of live birth rate, pregnancy rate and miscarriage rate between the two groups of embryo selection by "NICS+ morphology" and embryo selection only by "morphology" in IVF cycle.
Chromosomal aneuploidies are linked with spontaneous miscarriages and abnormal offspring in human pregnancies. In addition, some types of aneuploidies are reported to prevent implantation. Thus, there is a need to identify the embryos with highest implantation potential on in vitro fertilization (IVF) programs. Since embryo morphology and kinetics have a weak association with embryo ploidy, trophectoderm biopsy plus Next-Generation Sequencing (NGS) is becoming a very popular approach to determine the embryo chromosomal status. This technique is called Preimplantation Genetic Testing for Aneuploidy (PGT-A). Although shown to be efficient, it is invasive for the embryo, requires specific technical skills and it remains expensive. Therefore, the development of a non-invasive, rapid and cheaper method for assessing embryo ploidy status would represent a progress in the field of IVF. The non-invasive approach has been explored by some groups that analyzed the Spent Blastocyst Medium (SBM) where the embryo was incubated up to the time of transfer or freezing. In daily routine, this media is discarded after finishing the culture of the embryo. Importantly, though, this media reportedly contains traces of embryonic cell-free DNA (cfDNA) that can represent the genetic load of the embryo. On the basis of that, the hypothesis of this study is that embryo prioritization according to the analysis of the embryonic cfDNA in the SBM could improve ongoing pregnancy rate in 10 percentual points compared to standard blastocyst transfer based on morphology.
This study aims to validate a non-invasive method of chromosomal screening (NICS), based on the Multiple Annealing and Looping Based Amplification Cycles- Next-generation Sequencing (MALBAC-NGS) technology, in order to determine the chromosomal endowment of a blastocyst from the DNA of the embryonic culture medium. The chromosomal status of the embryo from an embryo biopsy of trophoectoderm will be established (usual clinical practice), the chromosomal endowment from the DNA of the embryonic culture medium will be determined, and the results using the NICS and the conventional invasive method (Preimplantation Genetic Testing for Aneuploidy [PGT-A]) will be compared.
The aim of this study was to evaluate the effect of counseling for prenatal screening and diagnostic tests on pregnant women's decisional conflict, being sure of the decision, anxiety levels, and attitudes towards the tests. This prospective randomized controlled intervention study was conducted between the dates June 2017 and March 2018 in a training and research hospital, department of obstetrics and gynecology. The sample of the study consisted of 210 pregnant women who took antenatal care between the 8-11th gestational weeks of whom 112 were in the intervention group and 98 were in the control group. The data were collected by using Data Collection Form, The State-Trait Anxiety Inventory (STAI I-II), Decisional Conflict Scale (DCS), Sure Scale (SURE), Knowledge Evaluation Form about Prenatal Genetic Screening and Diagnostic Tests, Prenatal Counseling Satisfaction Form, Decision Satisfaction Form and Attitudes towards the tests Scale. The study carried out in two stages. In the first stage; women's data were collected before and after participating prenatal genetic screening tests. After the results of the screening test were taken, the data were collected again. Counseling was provided for 112 pregnant women about prenatal screening and diagnostic tests before participating tests. Routine clinical information was given for 98 pregnant women who were in control group. Both groups were pre and post-tested at the same times. In the second phase, pregnant women who had diagnostic tests were evaluated. Counseling for prenatal genetic diagnosis tests was provided for 31 pregnant women in inetervetion group women and routine clinical information was providen for 26 pregnant women who were in control group. Data were collected again with data collection tools before and after the diagnostic test.
Mosaicism within an embryo is defined as the presence of two or more cell populations with different genotypes. Blastocysts classified as mosaic by Preimplamtation Genetic Testing for Aneuploidy (PGT-A) have been reported to implant less and miscarry more frequently than embryos classified as euploid. Because of the unknown impact of mosaicism on embryo development, these embryos are given low priority and are discarded for transfer. However, recent papers on the transfer of human embryos classified by PGT-A as mosaic suggest that embryos with a low fraction of abnormal cells resulting in viable, chromosomally normal ongoing pregnancies, and high-level mosaics resulting in fewer viable pregnancies, but so far none producing mosaic babies. The apparent presence of mosaicism in an embryo is used as a selection criteria for embryo transfer (ET), introducing a strong bias in terms of patient prognosis and embryo quality. Additionally, it is also possible that some embryos are incorrectly classified as "mosaic" due to technical variability derived from the processing of a uniform aneuploid embryo. The aims of this study is to provide evidences about the clinical significance of chromosomal mosaicism in PGT-A cycles by a prospective non-selection based methodology.