Unknown,Transcriptomics,Genomics,Proteomics

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DNA Replication Timing is Maintained Genome-wide in Primary Human Myoblasts Independent of D4Z4 Contraction in FSH Muscular Dystrophy

ABSTRACT: Facioscapulohumeral muscular dystrophy (FSHD) is linked to contraction of an array of tandem 3.3-kb repeats (D4Z4) at 4q35.2 from 11-100 copies to 1-10 copies. The extent to which D4Z4 contraction at 4q35.2 affects overall 4q35.2 chromatin organization remains unclear. Because DNA replication timing is highly predictive of long-range chromatin interactions, we generated genome-wide replication-timing profiles for FSHD and control myogenic precursor cells. We compared non-immortalized myoblasts from four FSHD patients and three control individuals to each other and to a variety of other human cell types. This study also represents the first genome-wide comparison of replication timing profiles in non-immortalized human cell cultures. Myoblasts from both control and FSHD individuals all shared a myoblast-specific replication profile. In contrast, male and female individuals were readily distinguished by monoallelic differences in replication timing at DXZ4 and other regions across the X chromosome affected by X inactivation. We conclude that replication timing is a robust cell-type specific feature that is unaffected by FSHD-related D4Z4 contraction. Profile comparison of myoblast cultures from four FSHD patients and three control individuals

ORGANISM(S): Homo sapiens

SUBMITTER: Benjamin Pope

PROVIDER: E-GEOD-34197 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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DNA Replication Timing is Maintained Genome-wide in Primary Human Myoblasts Independent of D4Z4 Contraction in FSH Muscular Dystrophy

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