Search results for "uniparental disomy"
showing 10 items of 15 documents
Assessment of Clonal Evolution in 42 AML with NPM1 Mutations by Molecular Characterization of Paired Diagnosis and Relapse Samples
2011
Abstract Abstract 237 Mutations in the nucleophosmin 1 (NPM1) gene represent one of the most frequent gene mutations in acute myeloid leukemia (AML), in particular in cytogenetically normal (CN)-AML. NPM1 mutations (NPM1mut) are considered as an early genetic event in the pathogenesis of AML. To address the role of clonal evolution from diagnosis to relapse in NPM1mut AML, we applied high-resolution genome-wide single nucleotide polymorphism (SNP) array analysis using the Affymetrix 6.0 platform to detect copy number alterations (CNAs) and uniparental disomies (UPDs) in paired samples from 42 patients. In addition, we determined NPM1 and FLT3 [internal tandem duplication (ITD) and tyrosine …
Forty-two supernumerary marker chromosomes (SMCs) in 43,273 prenatal samples: chromosomal distribution, clinical findings, and UPD studies.
2005
Fluorescence in situ hybridization (FISH) analyses were performed on supernumerary marker chromosomes (SMCs) detected in 43 273 prenatal diagnoses over a period of 11 years, 1993–2003. A total of 42 pregnancies with SMC were identified, indicating a prevalence of one in 1032. A total of 15 SMCs were endowed with detectable euchromatin (prevalence, 1/2884), including six SMCs containing the cat eye critical region (CECR) on chromosome 22q11.21 (1/7212). De novo SMCs were found in 29 pregnancies (1/1492), including 14 euchromatic SMCs (48.2%). Follow-up studies were available for 24 cases. Nine pregnancies (37.5%) were terminated; two children (8.3%) were born with Pallister–Killian syndrome …
Sleep disturbances in Angelman syndrome: a questionnaire study.
2003
Only few studies are available on sleep disorders in Angelman syndrome (AS), a neurodevelopmental disorder with several behavior disturbances. The aim of this study was to determine the prevalence of sleep disorders in a relatively large group of AS subjects, compared to that of age-matched controls. Forty-nine consecutive parents of patients with AS (26 males and 23 females aged 2.3-26.2 years) were interviewed and filled out a comprehensive sleep questionnaire. Based on their genetic etiology, four groups were defined: deletion of chromosome 15q11-13 (25 subjects); methylation imprinting mutation (six subjects), UBE3A mutations (seven subjects) and paternal uniparental disomy (five subjec…
SNPs array karyotyping reveals a novel recurrent 20p13 amplification in primary myelofibrosis.
2011
The molecular pathogenesis of primary mielofibrosis (PMF) is still largely unknown. Recently, single-nucleotide polymorphism arrays (SNP-A) allowed for genome-wide profiling of copy-number alterations and acquired uniparental disomy (aUPD) at high-resolution. In this study we analyzed 20 PMF patients using the Genome-Wide Human SNP Array 6.0 in order to identify novel recurrent genomic abnormalities. We observed a complex karyotype in all cases, detecting all the previously reported lesions (del(5q), del(20q), del(13q), +8, aUPD at 9p24 and abnormalities on chromosome 1). In addition, we identified several novel cryptic lesions. In particular, we found a recurrent alteration involving cytob…
Case report : partial uniparental disomy unmasks a novel recessive mutation in the LYST gene in a patient with a severe phenotype of Chediak-Higashi …
2021
Síndrome de Chédiak-Higashi; LYST; Disomia uniparental Síndrome de Chédiak-Higashi; LYST; Disomía uniparental Chédiak-Higashi syndrome; LYST; Uniparental disomy Chédiak-Higashi syndrome (CHS) is a rare autosomal recessive (AR) immune disorder that has usually been associated to missense, nonsense or indels mutations in the LYST gene. In this study, we describe for the first time the case of a CHS patient carrying a homozygous mutation in the LYST gene inherited as a result of a partial uniparental isodisomy (UPiD) of maternal origin. Sanger sequencing of the LYST cDNA and single nucleotide polymorphism (SNP)-arrays were performed to identify the causative mutation and to explain the molecul…
Novel deletion of the E3A ubiquitin protein ligase gene detected by multiplex ligation-dependent probe amplification in a patient with Angelman syndr…
2010
Angelman syndrome (AS) is a severe neurobehavioural disorder caused by failure of expression of the maternal copy of the imprinted domain located on 15q11-q13. There are different mechanisms leading to AS: maternal microdeletion, uniparental disomy, defects in a putative imprinting centre, mutations of the E3 ubiquitin protein ligase (UBE3A) gene. However, some of suspected cases of AS are still scored negative to all the latter mutations. Recently, it has been shown that a proportion of negative cases bear large deletions overlapping one or more exons of the UBE3A gene. These deletions are difficult to detect by conventional gene-scanning methods due to the masking effect by the non-delete…
Genome-wide parent-of-origin DNA methylation analysis reveals the intricacies of human imprinting and suggests a germline methylation-independent mec…
2014
Genomic imprinting is a form of epigenetic regulation that results in the expression of either the maternally or paternally inherited allele of a subset of genes (Ramowitz and Bartolomei 2011). This imprinted expression of transcripts is crucial for normal mammalian development. In humans, loss-of-imprinting of specific loci results in a number of diseases exemplified by the reciprocal growth phenotypes of the Beckwith-Wiedemann and Silver-Russell syndromes, and the behavioral disorders Angelman and Prader-Willi syndromes (Kagami et al. 2008; Buiting 2010; Choufani et al. 2010; Eggermann 2010; Kelsey 2010; Mackay and Temple 2010). In addition, aberrant imprinting also contributes to multige…
Pigmentary mosaicism in hypomelanosis of Ito
1998
We report on a female with mental and motor retardation, facial dysmorphism, abnormal pigmentation reminiscent to hypomelanosis of Ito (HI), and karyotypic mosaicism involving a small supernumerary marker chromosome. The marker chromosome was defined by fluorescence in situ hybridisation (FISH) as a ring X chromosome with breakpoints in the juxtacentromeric region. FISH analysis showed that the ring does not include the XIST locus at the X-inactivation centre and, therefore, may not be subject to X inactivation. X-inactivation studies with the HUMARA (human androgen receptor) and FMR1 assay showed a skewed X-inactivation pattern (85:15) with preferential inactivation of the paternal X chrom…
Prevalence of Angelman syndrome and Prader-Willi syndrome in Estonian children: sister syndromes not equally represented.
2006
In 2000-2004, we performed a focused search for individuals with Angelman syndrome (AS) and Prader-Willi syndrome (PWS) aiming to establish the prevalence data for the individuals born between 1984 and 2004 in Estonia. All persons with probable AS or PWS (n = 184) were studied using the DNA methylation test. Individuals with abnormal methylation were all further tested by chromosomal and FISH analysis, and if necessary for uniparental disomy and UBE3A gene mutation. Nineteen cases with abnormal methylation test result were identified. Seven of them had AS, including six (85.7%) due to 15q11-13 deletion and one paternal UPD15. Twelve subjects had PWS: 4 (33%) 15q11-13 deletions, 6 (50%) mate…
Testicular sperm from patients with obstructive and nonobstructive azoospermia: aneuploidy risk and reproductive prognosis using testicular sperm fro…
2010
Objective To establish a baseline incidence of chromosomal abnormalities in testicular sperm of fertile men and to determine the best control sample for comparisons with azoospermic males to estimate their reproductive prognosis. Design Prospective study. Setting Infertility clinic. Patient(s) Sixteen obstructive azoospermic (OA) and 19 nonobstructive azoospermic patients (NOA). Control samples were ejaculated sperm from ten fertile donors and testicular sperm from ten other fertile donors. Intervention(s) Fluorescence in situ hybridization (FISH) in sperm. Main Outcome Measure(s) Sperm numerical abnormalities for chromosomes 13, 18, 21, X, and Y; ongoing implantation and pregnancy rates in…