title: An unstable triplet repeat in a gene related to myotonic muscular dystrophy.
abstract: Synthetic oligonucleotides containing GC-rich triplet sequences were used in a scanning strategy to identify unstable genetic sequences at the myotonic dystrophy (DM) locus. A highly polymorphic GCT repeat was identified and found to be unstable, with an increased number of repeats occurring in DM patients. In the case of severe congenital DM, the paternal triplet allele was inherited unaltered while the maternal, DM-associated allele was unstable. These studies suggest that the mutational mechanism leading to DM is triplet amplification, similar to that occurring in the fragile X syndrome. The triplet repeat sequence is within a gene (to be referred to as myotonin-protein kinase), which has a sequence similar to protein kinases.
authors.affiliation: Institute for Molecular Genetics, Baylor College of Medicine, Houston, TX 77030.
authors.forename: Y H
authors.initials: YH
authors.lastname: Fu
authors.forename: A
authors.initials: A
authors.lastname: Pizzuti
authors.forename: R G
authors.initials: RG
authors.lastname: Fenwick
authors.forename: J
authors.initials: J
authors.lastname: King
authors.forename: S
authors.initials: S
authors.lastname: Rajnarayan
authors.forename: P W
authors.initials: PW
authors.lastname: Dunne
authors.forename: J
authors.initials: J
authors.lastname: Dubel
authors.forename: G A
authors.initials: GA
authors.lastname: Nasser
authors.forename: T
authors.initials: T
authors.lastname: Ashizawa
authors.forename: P
authors.initials: P
authors.lastname: de Jong
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002888:Chromosomes, Human, Pair 19; D003001:Cloning, Molecular; D004247:DNA / Q000737:chemistry; D006801:Humans; D008969:Molecular Sequence Data; D009154:Mutation; D009223:Myotonic Dystrophy / Q000235:genetics*; D009693:Nucleic Acid Hybridization; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D012091:Repetitive Sequences, Nucleic Acid
chemical_list: D004247:DNA