Researchers have shown that patients with a neurodegenerative disease known as SCAN1 (spinocerebellar ataxia with axonal neuropathy-1) may have trouble repairing a specific type of defect in their DNA.
The disease, which causes degeneration of the brain and spinal cord, is caused by mutations in the protein TDP1 (tyrosyl phosphodiesterase 1). But the known function of this enzyme in the repair of DNA double-strand breaks during cell replication seemed unlikely to cause the observed pathology.
In the 03 March 2005 issue of Nature (Vol. 434, No. 7029, pp. 108-113), Keith Caldecott and his co-workers reveal a second function for TDP1 in non-dividing neurons; that is, the repair of single-strand DNA breaks in chromosomes caused by oxidative stress. Problems repairing these breaks may make the neuronal genome unstable and underlie the disease, the authors say.
Keith Caldecott (University of Sussex, Brighton, UK)
Tel: +44 1273 678 123
(C) Nature pess release.
Message posted by: Trevor M. D'Souza