title: Pathogenic RNA repeats: an expanding role in genetic disease.
abstract: Fragile X mental retardation and Friedreich's ataxia were among the first pathogenic trinucleotide repeat disorders to be described in which noncoding repeat expansions interfere with gene expression and cause a loss of protein production. Invoking a similar loss-of-function hypothesis for the CTG expansion causing myotonic dystrophy type 1 (DM1) located in the 3' noncoding portion of a kinase gene was more difficult because DM is a dominantly inherited multisystemic disorder in which the second copy of the gene is unaffected. However, the discovery that a transcribed but untranslated CCTG expansion causes myotonic dystrophy type 2 (DM2), along with other discoveries on DM1 and DM2 pathogenesis, indicate that the CTG and CCTG expansions are pathogenic at the RNA level. This review will detail recent developments on the molecular mechanisms of RNA pathogenesis in DM, and the growing number of expansion disorders that might involve similar pathogenic RNA mechanisms.
authors.affiliation: Institute of Human Genetics, MMC 206, 420 Delaware St S.E., University of Minnesota, Minneapolis, MN 55455, USA. ranum001@umn.edu
authors.forename: Laura P W
authors.initials: LP
authors.lastname: Ranum
authors.forename: John W
authors.initials: JW
authors.lastname: Day
mesh_terms: D017398:Alternative Splicing / Q000235:genetics; D042622:DNA Repeat Expansion / Q000235:genetics*; D005799:Genes, Dominant / Q000235:genetics; D030342:Genetic Diseases, Inborn / Q000235:genetics*; D018398:Homeodomain Proteins / Q000235:genetics; D006801:Humans; D008957:Models, Genetic; D009223:Myotonic Dystrophy / Q000235:genetics*; D065636:Myotonin-Protein Kinase; D017346:Protein Serine-Threonine Kinases / Q000235:genetics; D011506:Proteins / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000378:metabolism
chemical_list: C585517:DMPK protein, human; C081088:DMWD protein, human; D018398:Homeodomain Proteins; D011506:Proteins; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; C106687:SIX5 protein, human; D065636:Myotonin-Protein Kinase; D017346:Protein Serine-Threonine Kinases