Search results for "mosaicism"
showing 10 items of 31 documents
Familial ring (18) mosaicism in a 23-year-old young adult with 46,XY,r(18) (::p11→q21::)/46,XY karyotype, intellectual disability, motor retardation …
2010
We report on a 23-year-old man with craniofacial findings of the holoprosencephaly spectrum disorder (microcephaly, hypotelorism, depressed nasal bridge, single median maxillary central incisor), fusion of C2-C3 vertebrae, intellectual disability, and severe sleep apnea. Chromosome analysis of blood lymphocytes showed 75% ring (18) cells and 25% normal cells, karyotype mos 46,XY,r(18)(::p11→q21::)[75]/46,XY[25]. His mother was phenotypically normal except for a double ureter and bifid renal pelvis as in his son. She had a supernumerary ring (18) in 10% of blood lymphocytes, karyotype mos 47,XX,+r(18)(::p11→q21::)[10]/46,XX[90]. Familial ring (18) is a rare cytogenetic abnormality. This is t…
A two base pair deletion in the PQBP1 gene is associated with microphthalmia, microcephaly, and mental retardation.
2007
X-linked mental retardation has been traditionally divided into syndromic (S-XLMR) and non-syndromic forms (NS-XLMR), although the borderlines between these phenotypes begin to vanish and mutations in a single gene, for example PQBP1, can cause S-XLMR as well as NS-XLMR. Here, we report two maternal cousins with an apparently X-linked phenotype of mental retardation (MR), microphthalmia, choroid coloboma, microcephaly, renal hypoplasia, and spastic paraplegia. By multipoint linkage analysis with markers spanning the entire X-chromosome we mapped the disease locus to a 28-Mb interval between Xp11.4 and Xq12, including the BCOR gene. A missense mutation in BCOR was described in a family with …
X-inactivation pattern in three cases of X/autosome translocation.
1978
We describe an X/15 translocation which was balanced in a phenotypically normal mother [46,X,t(X;15)(p22;q15)] and unbalanced in her phenotypically abnormal daughter [46,X,der(X),t(X;15)(p22;q15)mat]. A third case involves a balanced X/21 translocation in a girl with a multiple congenital anomaly-retardation syndrome [46,X,t(X;21)(p11;p11?)]. 5-BrdU acridine orange banding on lymphocytes revealed late replication of the normal X chromosome in the mother and of the normal or abnormal X chromosome in the two other cases. Our findings are only partially consistent with previous observations. All X-inactivation patterns can be explained by random inactivation and subsequent selection against sp…
Mosaicism due to postzygotic mutations in women with focal dermal hypoplasia
2019
International audience; Focal dermal hypoplasia (FDH, Goltz syndrome, MIM: #305600) constitutes a rare multisystem genetic disorder of the skin, skeleton, teeth and eyes with considerable variation in the clinical features. FDH is transmitted as an X-linked dominant trait and is caused by mutations in PORCN. In males, hemizygous PORCN mutations are lethal in utero. Around 300 cases have been reported in the literature to date. About 10% of them are males presenting either Klinefelter syndrome (karyotype 47, XXY) or mosaicism of a postzygotic mutation. Here we describe four cases of women with typical features of FDH, in whom a PORCN mutation was found in DNA from affected cutaneous tissue b…
Improved accuracy of hysteroembryoscopic biopsies for karyotyping early missed abortions
2003
Abstract Objective To assess the potential of direct embryo and chorion biopsies obtained by hysteroembryoscopy for karyotyping early missed abortions. Design Clinical prospective descriptive study. Setting Instituto Valenciano de Infertilidad, Valencia, Spain. Patient(s) Sixty-eight women (71 gestational sacs) with missed abortions. The gestational age on ultrasound was 6.3 weeks (range, 4–10 weeks). Intervention(s) Transcervical hysteroembryoscopy before curettage. Main outcome measure(s) Comparison between the cytogenetic results from hysteroembryoscopic biospies and those of the curettage material. Result(s) Hysteroembryoscopic biopsies could be taken in 97.2% of the gestational sacs. D…
Impact of chromosomal abnormalities on preimplantation embryo development.
2007
Objectives To evaluate the influence of numerical chromosomal abnormalities on preimplantation embryo development. Methods This study includes 6936 embryos from 1245 women undergoing preimplantation genetic diagnosis (PGD). Indications for aneuploidy screening were: recurrent miscarriages, implantation failure, severe male factor, advanced maternal age, and mixed causes. Embryo biopsy was performed on day 3, and embryos were co-cultured until day 5, when embryo transfer was performed. Results In the aneuploidy screening regimen, normal euploid embryos showed significantly higher blastocyst rates (68.2%) compared to chromosomally abnormal (42.8%, p < 0.0001) and mosaic (53.7%, p < 0.0001) em…
Pathogenic correlation between mosaic variegated aneuploidy 1 (MVA1) and a novel BUB1B variant: a reappraisal of a severe syndrome.
2022
Funder: Università degli Studi di Catania
Compartmentalization of Central Neurons inDrosophila: A New Strategy of Mosaic Analysis Reveals Localization of Presynaptic Sites to Specific Segment…
2002
Synaptogenesis in the CNS has received far less attention than the development of neuromuscular synapses, although only central synapses allow the study of neuronal postsynaptic mechanisms and display a greater variety of structural and functional features. This neglect is attributable mainly to the enormous complexity of the CNS, which makes the visualization of individual synapses on defined neuronal processes very difficult. We overcome this obstacle and demonstrate by confocal microscopy the specific arrangement of output synapses on individual neurites. These studies are performed via genetic mosaic strategies in the CNS of the fruitfly Drosophila melanogaster. First, we use targeted e…
[Y chromosome in Turner syndrome].
2017
Turner syndrome (TS) is an inherited genetic disorder caused by numerical and/or structural chromosome X aberrations occurring at a frequency of 1:1200-1:2500 live-born girls. The most common karyotype is X chromosome monosomy (45,X) (approximately 50-60% of cases). Approximately 5-6% of patients may have abnormal Y chromosome or mosaicism characterized by the coexistence of 45,X cell line with cell line in which all or part of chromosome Y is present. In patients with TS who have all or fragmented genetic material from chromosome Y there is a substantial risk of cancerous lesions in these dysgenetic gonads. This paper stands for the review of the current knowledge on the genetic material o…
Toxicity of ligand-dependent Cre recombinases and generation of a conditional Cre deleter mouse allowing mosaic recombination in peripheral tissues.
2007
Ligand-activated Cre recombinases are widely used for studying gene function in vitro and in conditional mouse models. To compare ligand-dependent Cre recombinases, different Cre estrogen receptor fusions were introduced into the ROSA26 locus of embryonic stem (ES) cells and assayed for genotoxicity and recombination efficiency. Of the tested recombinases, the CreERT2 variant showed no toxicity and was highly responsive to ligand induction. To constitutively express CreERT2 in mice and also to clarify whether the CreERT2 system displays background activity, we generated a knock-in mouse line harboring the CreERT2 coding region under the control of the ROSA26 locus. Analysis of this ROSA26-…