Expanded CAG-CTG trinucleotide repeat tracts are associated with a number of hereditary neurodegenerative and neuromuscular diseases such as Huntington's disease, myotonic dystrophy and spinocerebellar ataxias. These diseases are characterized by the phenomenon of genetic anticipation, which is defined by a decrease in the age of onset and an increase in severity of the disease with successive ...

Huntington's Disease-like 2 (HDL2), like Huntington's disease (HD), is an adult onset, progressive, neurodegenerative autosomal dominant disorder clinically characterized by abnormal movements, dementia, and psychiatric syndromes. Like HD, the neuropathology of HDL2 features prominent cortical and striatal atrophy and intranuclear inclusions. HDL2 is generally rare, accounting for only a few pe...

Myotonic dystrophy (DM1) is known to be an adult-onset muscular dystrophy caused by the expansion of CTG repeats within the 3' untranslated region of the dystrophin myotonin protein kinase (DMPK) gene. The clinical features of DM1 include CNS symptoms, such as cognitive impairment and personality changes, the pathogenesis of which remains to be elucidated. We hypothesized that the distribution ...

The general model that dominant diseases are caused by mutations that result in a gain or change in function of the corresponding protein was challenged by the discovery that the myotonic dystrophy type 1 mutation is a CTG expansion located in the 3' untranslated portion of a kinase gene. The subsequent discovery that a similar transcribed but untranslated CCTG expansion in an intron causes the...

Dystrophia myotonica (DM) type 1 is an autosomal dominant disorder, caused by a trinucleotide CTG repeat expansion in the 3' untranslated region of the dystrophia myotonica protein kinase (DMPK) gene (chromosome 19q13.3). The disorder affects different organ systems, including the skeletal muscles, ocular lens, lungs, heart and gastrointestinal tract, as well as the endocrine and central nervou...

Repetitive DNA elements are mutational hotspots in the genome, and their instability is linked to various neurological disorders and cancers. Although it is known that expanded trinucleotide repeats can interfere with DNA replication and repair, the cellular response to these events has not been characterized. Here, we demonstrate that an expanded CAG/CTG repeat elicits a DNA damage checkpoint ...

Expansions of trinucleotide CAG/CTG repeats in somatic tissues are thought to contribute to ongoing disease progression through an affected individual's life with Huntington's disease or myotonic dystrophy. Broad ranges of repeat instability arise between individuals with expanded repeats, suggesting the existence of modifiers of repeat instability. Mice with expanded CAG/CTG repeats show varia...