Telomeres protect chromosome ends and control cell division and senescence. During organogenesis, telomeres need to be long enough to ensure the cell proliferation necessary at this stage of development. Previous studies have shown that telomere shortening is associated with growth retardation and congenital malformations.
View Article and Find Full Text PDFAnn Biol Clin (Paris)
October 2020
Objective: Principal objective of this work was to analyse the cost effectiveness of different sequences of cytogenetic techniques from the hospital's point of view, after prenatal ultrasound has identified fetal malformations.
Methods: Cytogenetic tests were performed for each case in 3 strategies, and their results are reported and compared to one reference strategy. Two new simulated strategies were considered: chromosomal microarrays alone and a direct test + CMA.
In high-risk neuroblastoma (HR-NB), the clinical significance of long-term minimal residual disease (MRD) monitoring using quantitative reverse transcription-polymerase chain reaction (qRT-PCR) for neuroblastoma mRNAs has not been investigated. We report long-term MRD follow-ups of four patients with HR-NB throughout the disease (diagnosis, remission, and relapse) and treatment course (chemotherapy, autologous and allogeneic stem cell transplantation, and donor lymphocyte and natural killer cell infusions). The results showed the stability of mRNA marker expression after different treatments and demonstrated their validity to predict relapse and assess therapeutic response.
View Article and Find Full Text PDFResearch Question: Is sperm fluorescence in-situ hybridization (FISH) useful to evaluate the risk of chromosomally unbalanced gametes in interchromosomal reciprocal insertion (IRI) carriers? How do these imbalances lead to recurrent miscarriages?
Design: This study reports a clinical and molecular study of a rare familial balanced IRI resulting in recurrent spontaneous miscarriage. Sperm FISH was performed to estimate the number of unbalanced gametes.
Results: A 31-year-old healthy male (proband) and his 28-year-old female partner were referred to the Genetics Department for three spontaneous miscarriages occurring during the first trimester of pregnancy.
In the interphase cell nucleus, chromosomes adopt a conserved and non-random arrangement in subnuclear domains called chromosome territories (CTs). Whereas chromosome translocation can affect CT organization in tumor cell nuclei, little is known about how aneuploidies can impact CT organization. Here, we performed 3D-FISH on control and trisomic 21 nuclei to track the patterning of chromosome territories, focusing on the radial distribution of trisomic HSA21 as well as 11 disomic chromosomes.
View Article and Find Full Text PDFUpregulation of the telomerase reverse transcriptase () gene in human cancers leads to telomerase activation, which contributes to the growth advantage and survival of tumor cells. Molecular mechanisms of upregulation are complex, tumor-specific and can be clinically relevant. To investigate these mechanisms in breast cancer, we sequenced the promoter, evaluated copy number changes and assessed the expression of the oncogene, a known transcriptional regulator, in two breast cancer cohorts comprising a total of 122 patients.
View Article and Find Full Text PDFDysfunctional telomeres and DNA damage repair (DDR) play important roles in cancer progression. Studies have reported correlations between these factors and tumour aggressiveness and clinical outcome in breast cancer. We studied the characteristics of telomeres and expression of ERCC1, a protein involved in a number of DNA repair pathways and in telomere homeostasis, to assess their prognostic value, alone or in combination, in 90 residual breast tumours after treatment with neoadjuvant chemotherapy (NCT).
View Article and Find Full Text PDFIn chronic lymphocytic leukemia (CLL), telomere dysfunction is associated with poor outcomes. TP53 is involved in cellular responses to dysfunctional telomeres, and its inactivation is the strongest adverse prognostic factor for CLL. Given the biological relationship between TP53 and telomeres, and their prognostic value, it is important to improve our understanding of the impact of TP53 alterations on telomeres.
View Article and Find Full Text PDFAfter defining the terms "perfect," "chromosomically" and "right" we discuss on the scope and terms of the right to a chromosomically perfect child. This right is it addressed to a target population or to the general population? What are the exams available and the means of diagnosis or screening to be implemented? The practice of genetic testing being highly controlled, some rules are then discussed. All over the paper, a reflection is proposed on what is allowed versus what is possible with reference to ethics.
View Article and Find Full Text PDFBirth Defects Res A Clin Mol Teratol
September 2016
Background: Microdeletions encompassing chromosome bands 2q14.1q14.3 are rare.
View Article and Find Full Text PDFBackground: Fifty percent of spontaneous miscarriages (SMs) are attributed to chromosomal abnormalities. Cytogenetic analysis is an important tool for patient counselling and assessment of the risk of recurrence in future pregnancies. Conventional karyotyping has been the gold standard for chromosomal investigation of products of conception (POC), but it has limitations due to sample maceration, culture failure and maternal cell contamination.
View Article and Find Full Text PDFCytogenet Genome Res
March 2016
Fetuses with increased nuchal translucency thickness (NT) are at increased risk for chromosomal abnormalities. In case of a normal karyotype, a minority of them may present with structural abnormalities or genetic syndromes, which may be related to submicroscopic chromosomal imbalances. The objective of this study was to evaluate whether MLPA screening of 21 syndromic and subtelomeric regions could improve the detection rate of small chromosomal aberrations in fetuses with increased NT and a normal karyotype.
View Article and Find Full Text PDFObjectives: The implementation of chromosomal microarray analysis (CMA) in prenatal testing for all patients has not achieved a consensus. Technical alternatives such as Prenatal BACs-on-Beads(TM) (PNBoBs(TM) ) have thus been applied. The aim of this study was to provide the frequencies of the submicroscopic defects detectable by PNBoBs(TM) under different prenatal indications.
View Article and Find Full Text PDFMicrodeletions of 17q12 encompassing TCF2 are associated with maturity-onset of diabetes of the young type 5, cystic renal disease, pancreatic atrophy, Mullerian aplasia in females and variable cognitive impairment. We report on a patient with a de novo 17q12 microdeletion, 1.8 Mb in size, associated with congenital diaphragmatic hernia (CDH).
View Article and Find Full Text PDFHigh proportion of disease-associated copy number variant maps to chromosome 17. Genomic studies have provided an insight into its complex genomic structure such as relative abundance of segmental duplication and intercepted repetitive elements. 17q21.
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