{"type": "root", "children": [{"type": "p", "children": [{"type": "t", "text": "\n Facioscapulohumeral muscular dystrophy (FSHD) is now understood to arise from epigenetic de‐repression of the 4q35 region following a contraction of the D4Z4 repeat array. Central to this pathogenic cascade is the expression of the chromatin‐associated long noncoding RNA DBE-T, which is selectively produced in affected individuals."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "1"}]}, {"type": "t", "text": " DBE-T functions by recruiting the Trithorax group protein Ash1L to the FSHD locus, thereby promoting histone H3 lysine 36 dimethylation and subsequent chromatin remodeling that drives transcriptional activation of 4q35 genes. This mechanism links reduced repeat copy number with a loss of Polycomb silencing and the subsequent misexpression of genes implicated in FSHD pathogenesis. Further, analyses of complex deletion alleles (DPED) have revealed that DBE-T can be among the genetic elements lost, prompting a re-evaluation of its contribution to the disease phenotype."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "2"}]}, {"type": "t", "text": "\n "}]}, {"type": "rg", "children": [{"type": "r", "ref": 1, "children": [{"type": "t", "text": "Daphne S Cabianca, Valentina Casa, Beatrice Bodega, et al. "}, {"type": "b", "children": [{"type": "t", "text": "A long ncRNA links copy number variation to a polycomb/trithorax epigenetic switch in FSHD muscular dystrophy."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Cell (2012)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1016/j.cell.2012.03.035"}], "href": "https://doi.org/10.1016/j.cell.2012.03.035"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "22541069"}], "href": "https://pubmed.ncbi.nlm.nih.gov/22541069"}]}, {"type": "r", "ref": 2, "children": [{"type": "t", "text": "Richard J L F Lemmers, Patrick J van der Vliet, David San Leon Granado, et al. "}, {"type": "b", "children": [{"type": "t", "text": "High-resolution breakpoint junction mapping of proximally extended D4Z4 deletions in FSHD1 reveals evidence for a founder effect."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Hum Mol Genet (2022)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1093/hmg/ddab250"}], "href": "https://doi.org/10.1093/hmg/ddab250"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "34559225"}], "href": "https://pubmed.ncbi.nlm.nih.gov/34559225"}]}]}]}