Publications by authors named "Sara Winokur"

Autosomal dominant facioscapulohumeral muscular dystrophy (FSHD) is likely caused by epigenetic alterations in chromatin involving contraction of the D4Z4 repeat array near the telomere of chromosome 4q. The precise mechanism by which deletions of D4Z4 influence gene expression in FSHD is not yet resolved. Regulatory models include a cis effect on proximal gene transcription (position effect), DNA looping, non-coding RNA, nuclear localization and trans-effects.

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Facioscapulohumeral dystrophy (FSHD) is an autosomal dominant muscular dystrophy in which no mutation of pathogenic gene(s) has been identified. Instead, the disease is, in most cases, genetically linked to a contraction in the number of 3.3 kb D4Z4 repeats on chromosome 4q.

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Deletion of a subset of the D4Z4 macrosatellite repeats in the subtelomeric region of chromosome 4q causes facioscapulohumeral muscular dystrophy (FSHD) when occurring on a specific haplotype of 4qter (4qA161). Several genes have been examined as candidates for causing FSHD, including the DUX4 homeobox gene in the D4Z4 repeat, but none have been definitively shown to cause the disease, nor has the full extent of transcripts from the D4Z4 region been carefully characterized. Using strand-specific RT-PCR, we have identified several sense and antisense transcripts originating from the 4q D4Z4 units in wild-type and FSHD muscle cells.

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Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominant disorder linked to contractions of the D4Z4 repeat array in the subtelomeric region of chromosome 4q. By comparing genome-wide gene expression data from muscle biopsies of patients with FSHD to those of 11 other neuromuscular disorders, paired-like homeodomain transcription factor 1 (PITX1) was found specifically up-regulated in patients with FSHD. In addition, we showed that the double homeobox 4 gene (DUX4) that maps within the D4Z4 repeat unit was up-regulated in patient myoblasts at both mRNA and protein level.

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Gene expression profiling has been widely used to study molecular signatures of many diseases and to develop molecular diagnostics for disease prediction. Gene selection, as an important step for improved diagnostics, screens tens of thousands of genes and identifies a small subset that discriminates between disease types. A two-step gene selection method is proposed to identify informative gene subsets for accurate classification of multiclass phenotypes.

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RNA interference (RNAi) is implicated in maintaining tandem DNA arrays as constitutive heterochromatin. We used chromatin immunoprecipitation with antibodies to RNA polymerase II (RNAPol-ChIP) to test for transcription of the following repeat arrays in human cells: subtelomeric D4Z4, pericentromeric satellite 2, and centromeric satellite alpha. D4Z4 has a promoter-like sequence upstream of an ORF in its 3.

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Mutations of lamin A/C (LMNA) cause a wide range of human disorders, including progeria, lipodystrophy, neuropathies and autosomal dominant Emery-Dreifuss muscular dystrophy (EDMD). EDMD is also caused by X-linked recessive loss-of-function mutations of emerin, another component of the inner nuclear lamina that directly interacts with LMNA. One model for disease pathogenesis of LMNA and emerin mutations is cell-specific perturbations of the mRNA transcriptome in terminally differentiated cells.

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Facioscapulohumeral muscular dystrophy (FSHD) progressively affects the facial, shoulder, and upper arm muscles and is associated with contractions of the polymorphic D4Z4 repeat array in 4q35. Recently, we demonstrated that FSHD alleles are hypomethylated at D4Z4. To study potential relationships between D4Z4 hypomethylation and both residual repeat size and clinical severity, we compared the clinical severity score with D4Z4 methylation in unrelated FSHD patients.

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Facioscapulohumeral muscular dystrophy (FSHD) may be a new member of the class of neuromuscular diseases (NMD) due to defects in the nuclear envelope. Unlike other NMDs with primary defects in nuclear envelope proteins, however, FSHD may result from inappropriate chromatin interactions at the envelope. 3D Immuno-FISH and a novel method of 3D by 2D analysis using NucProfile were developed to examine nuclear organization of the FSHD genomic region.

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The autosomal dominant myopathy facioscapulohumeral muscular dystrophy (FSHD1, OMIM 158900) is caused by contraction of the D4Z4 repeat array on 4qter. We show that this contraction causes marked hypomethylation of the contracted D4Z4 allele in individuals with FSHD1. Individuals with phenotypic FSHD1, who are clinically identical to FSHD1 but have an unaltered D4Z4, also have hypomethylation of D4Z4.

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The neuromuscular disorder facioscapulohumeral muscular dystrophy (FSHD) results from integral deletions of the subtelomeric repeat D4Z4 on chromosome 4q. A disruption of chromatin structure affecting gene expression is thought to underlie the pathophysiology. The global gene expression profiling of mature muscle tissue presented here provides the first insight into an FSHD-specific defect in myogenic differentiation.

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Facioscapulohumeral muscular dystrophy is an autosomal dominant disorder resulting from an unusual genetic mechanism. The mutation, a deletion of 3.3 kb subtelomeric repeats, appears to disrupt the regional regulation of 4q35 g ene expression.

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