title: Association of CTG repeats and the 1-kb Alu insertion/deletion polymorphism at the myotonin protein kinase gene in the Japanese population suggests a common Eurasian origin of the myotonic dystrophy mutation.
abstract: We have studied linkage disequilibrium between CTG repeats and an Alu insertion/deletion polymorphism at the myotonin protein kinase gene (DMPK) in 102 Japanese families, of which 93 were affected with myotonic dystrophy (DM). All of the affected chromosomes are in complete linkage disequilibrium with the Alu insertion allele. Among the normal chromosomes, alleles of CTG repeats 5 and > or = 17 are exclusively associated with the insertion allele. On the other hand, intermediate alleles of 11-16 repeats show a significantly greater association with the deletion allele. A strikingly similar pattern of linkage disequilibrium observed in European populations suggests a common origin of the DM mutation in the Japanese and European populations.
authors.affiliation: Department of Geriatric Medicine, Osaka University Medical School, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Yamagata
authors.forename: T
authors.initials: T
authors.lastname: Miki
authors.forename: M
authors.initials: M
authors.lastname: Nakagawa
authors.forename: K
authors.initials: K
authors.lastname: Johnson
authors.forename: R
authors.initials: R
authors.lastname: Deka
authors.forename: T
authors.initials: T
authors.lastname: Ogihara
mesh_terms: D044466:Asian People / Q000235:genetics*; D005060:Europe; D006801:Humans; D007564:Japan; D015810:Linkage Disequilibrium; D009154:Mutation / Q000235:genetics; D009223:Myotonic Dystrophy / Q000235:genetics*; D065636:Myotonin-Protein Kinase; D011110:Polymorphism, Genetic; D011494:Protein Kinases / Q000235:genetics*; D017346:Protein Serine-Threonine Kinases; D012091:Repetitive Sequences, Nucleic Acid; D017384:Sequence Deletion / Q000235:genetics; D018911:Trinucleotide Repeats; D044465:White People / Q000235:genetics
chemical_list: C585517:DMPK protein, human; D011494:Protein Kinases; D065636:Myotonin-Protein Kinase; D017346:Protein Serine-Threonine Kinases