ABSTRACT
At least 15 human diseases have been associated with the length-dependent expansion of gene-specific (CTG).(CAG) repeats, including myotonic dystrophy (DM1) and spinocerebellar ataxia type 1 (SCA1). Repeat expansion is likely to involve unusual DNA structures. We have structurally characterized such DNA, with (CTG)(n).(CAG)(n) repeats of varying length (n=17-79), by high-resolution gel electrophoresis, and have probed their surfaces with anti-DNA antibodies of known specificities. We prepared homoduplex S-DNAs, which are (CTG)x.(CAG)y where x=y, and heteroduplex SI-DNAs, which are hybrids where x>y or xSubject(s)
Antibodies, Antinuclear/metabolism
, Myotonic Dystrophy/genetics
, Nucleic Acid Conformation
, Trinucleotide Repeats/immunology
, Antibody Specificity
, Ataxin-1
, Ataxins
, Base Pairing
, DNA/chemistry
, DNA/immunology
, DNA/metabolism
, Electrophoresis, Polyacrylamide Gel
, Humans
, Magnesium/metabolism
, Nerve Tissue Proteins/genetics
, Nuclear Proteins/genetics
, Nucleic Acid Heteroduplexes
, Nucleosides/immunology
, Surface Properties