This Article  • Full text  • PDF  • Send to a friend  • Save in My Folder  • Save to citation manager  • Permissions  Citing Articles  • Contact me when this article is cited  Related Content  • Similar articles in JAMA  Topic Collections  • Neurology  • Genetic Counseling/ Testing/ Therapy  • Genetic Disorders  • Alert me on articles by topic

Tracy Hampton, PhD

JAMA. 2007;297:2339.

	Since this article does not have an abstract, we have provided the first 150 words of the full text and any section headings.

Faulty DNA repair appears to be the cause of Huntington disease, according to a new study led by researchers at the Mayo Clinic in Rochester, Minn (Kovtun IV et al. Nature. doi:10.1038/nature05778 [published online ahead of print April 22, 2007]).

An accumulation (over time and with each successive generation in an affected family) of extra CAG nucleotides within the gene that encodes the protein huntingtin creates an abnormal version of the protein that has a destructive effect in the brain. The scientists found that this CAG expansion occurs when cells attempt to remove oxidative lesions within the DNA through a repair enzyme called 7,8-dihydro-8-oxoguanine-DNA glycosylase (OGG1).

When the investigators removed OGG1 in a mouse model of Huntington disease, most of the DNA's oxidative lesions remained untouched and CAG nucleotides did not expand as much as in mice with a working version of OGG1. Therefore, while OGG1 . . . [Full Text of this Article]