Search for DNA alterations in Alzheimer's disease

The DNA of brain cortex obtained from autopsy specimens of eight patients with Alzheimer's disease and eight controls was examined for content of normal and abnormal bases. DNA, purified by hydroxyapatite chromatography, was hydrolyzed under mild conditions and the deoxynucleosides were measured by high performance liquid chromatography (HPLC). No differences in the mole percentages of deoxynucleosides in DNA were detected in patients with Alzheimer's disease compared to controls, nor were abnormal deoxynucleosides found. Restriction-nuclease digests examined by agarose gel electrophoresis also showed no changes. Thus, diffuse and persistent damage to the DNA in brain in Alzheimer's disease was not detected by these methods.