Search results for "DELETION"
showing 10 items of 383 documents
Oligophrenin 1 mutations frequently cause X-linked mental retardation with cerebellar hypoplasia
2005
Background: Mutations of oligophrenin 1, one of the first genes identified in nonspecific X-linked mental retardation (MRX), have been described in patients with moderate to severe cognitive impairment and predominant cerebellar hypoplasia, in the vermis. Objective: To further delineate the phenotypic and mutational spectrum of the syndrome, by screening oligophrenin 1 in two cohorts of male patients with mental retardation (MR) with or without known posterior fossa anomalies. Methods: Clinical examination, cognitive testing, MRI studies, and mutational analysis (denaturing gradient gel electrophoresis and direct sequencing) on blood lymphocytes were performed in 213 unrelated affected indi…
Clinical and molecular genetic spectrum of autosomal dominant Emery-Dreifuss muscular dystrophy due to mutations of the lamin A/C gene.
2000
Emery-Dreifuss muscular dystrophy (EDMD) is characterized by early contractures of the elbows and Achilles tendons, slowly progressive muscle wasting and weakness, and life-threatening cardiomyopathy with conduction blocks. We recently identified LMNA encoding two nuclear envelope proteins, lamins A and C, to be implicated in the autosomal dominant form of EDMD. Here, we report on the variability of the phenotype and spectrum of LMNA mutations in 53 autosomal dominant EDMD patients (36 members of 6 families and 17 sporadic cases). Twelve of the 53 patients showed cardiac involvement exclusively, although the remaining 41 all showed muscle weakness and contractures. We were able to identify …
Clinical relevance of postzygotic mosaicism in Cornelia de Lange syndrome and purifying selection of NIPBL variants in blood.
2021
Postzygotic mosaicism (PZM) in NIPBL is a strong source of causality for Cornelia de Lange syndrome (CdLS) that can have major clinical implications. Here, we further delineate the role of somatic mosaicism in CdLS by describing a series of 11 unreported patients with mosaic disease-causing variants in NIPBL and performing a retrospective cohort study from a Spanish CdLS diagnostic center. By reviewing the literature and combining our findings with previously published data, we demonstrate a negative selection against somatic deleterious NIPBL variants in blood. Furthermore, the analysis of all reported cases indicates an unusual high prevalence of mosaicism in CdLS, occurring in 13.1% of p…
Two Novel Deletions (Array CGH Findings) in Pigment Dispersion Syndrome
2007
Purpose: We report the first male with pigment dispersion syndrome and a balanced translocation t(10;15)(p11.1;q11.1). Methods: Cytogenetic analyses using Giemsa banding and FISH methods, and array CGH were performed. Results: Array CGH analyses did not show altered DNA sequences in the breakpoints of the translocation, but revealed two novel deletions in 2q22.1 and 18q22.1. Conclusion: We suppose that the coexistence of t(10;15) and pigment dispersion syndrome in our patient is a coincidence. The deletion in 2q22.1, where the gene LRP1B has been located, may play a major role in the dysembryogenesis of the eye and cause the disorder.
A novel mutation in the coagulation factor 12 gene in subjects with hereditary angioedema and normal C1-inhibitor.
2011
In hereditary angioedema with normal C1-inhibitor two different missense mutations of codon p.Thr328* in the coagulation factor 12 gene have been reported in some families. In this study a novel factor 12 gene mutation, the deletion of 72 base pairs (bp) (c.971_1018+24del72*), was identified in a family of Turkish origin, in two sisters with recurrent skin swellings and abdominal pain attacks and in their symptom-free father. This deletion caused a loss of 48 bp of exon 9 (coding amino acids 324* to 340*) in addition to 24 bp of intron 9, including the authentic donor splice site of exon 9. The large deletion of 72 bp was located in the same F12 gene region as the missense mutations p.Thr32…
Ten new cases further delineate the syndromic intellectual disability phenotype caused by mutations in DYRK1A.
2015
The dual-specificity tyrosine-phosphorylation-regulated kinase 1A (DYRK1A) gene, located on chromosome 21q22.13 within the Down syndrome critical region, has been implicated in syndromic intellectual disability associated with Down syndrome and autism. DYRK1A has a critical role in brain growth and development primarily by regulating cell proliferation, neurogenesis, neuronal plasticity and survival. Several patients have been reported with chromosome 21 aberrations such as partial monosomy, involving multiple genes including DYRK1A. In addition, seven other individuals have been described with chromosomal rearrangements, intragenic deletions or truncating mutations that disrupt specificall…
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 …
Clonal evolution in relapsed NPM1-mutated acute myeloid leukemia.
2013
Mutations in the nucleophosmin 1 (NPM1) gene are considered a founder event in the pathogenesis of acute myeloid leukemia (AML). To address the role of clonal evolution in relapsed NPM1-mutated (NPM1mut) AML, we applied high-resolution, genome-wide, single-nucleotide polymorphism array profiling to detect copy number alterations (CNAs) and uniparental disomies (UPDs) and performed comprehensive gene mutation screening in 53 paired bone marrow/peripheral blood samples obtained at diagnosis and relapse. At diagnosis, 15 aberrations (CNAs, n = 10; UPDs, n = 5) were identified in 13 patients (25%), whereas at relapse, 56 genomic alterations (CNAs, n = 46; UPDs, n = 10) were detected in 29 patie…
Bcl-6 mutation status provides clinically valuable information in early-stage B-cell chronic lymphocytic leukemia
2004
In B-cell chronic lymphocytic leukemia (B-CLL), somatic mutation of IgVH genes defines a subgroup with favorable prognosis, whereas the absence of IgVH mutations is correlated with a worse outcome. Mutations of the BCL-6 gene are also observed in a subset of B-CLL, but the clinical significance of this molecular alteration remains uncertain. We examined the distribution of IgVH and BCL-6 gene mutations in 95 well-characterized patients with Binet stage A B-CLL, and correlated them with clinical, laboratory, cytogenetic findings and disease progression. Mutations of the BCL-6 gene were observed only in cases harboring mutated IgVH. Unexpectedly, coexistence of IgVH and BCL-6 mutations was co…
High prevalence of BRCA1 deletions in BRCAPRO-positive patients with high carrier probability.
2007
Mutation screening of the BRCA1 and BRCA2 genes in probands with familial breast/ovarian cancer has been greatly improved by the multiplex ligation-dependent probe amplification (MLPA) assay able to evidence gene rearrangements not detectable by standard screening methods. However, no criteria for selection of cases to be submitted to the MLPA test have been reported yet. We used the BRCAPro software for the selection of familial breast/ovarian cancer probands investigated with the MLPA approach after negative BRCA1/2 conventional mutation screening. One hundred and seventy-seven probands were investigated for germline BRCA1/2 mutations after assessment of genetic risk using BRCAPro. Proban…