Aging brains similar to diseased ones.

• Position: Neurodegenerative Disorders

Alzheimer's disease and frontotemporal lobar degeneration (FTLD) are two of the most prevalent forms of neurodegenerative disorders. In a study published in Genome Research, scientists have analyzed changes in gene expression in aging and diseased brains, finding new clues to the biology of normal aging and neurodegenerative diseases.

Recent studies have identified changes in how genes are read, or expressed, in the brain either during aging or with neurodegenerative disease. However, no previous study directly had compared gene expression changes in healthy aging with those in diseased individuals.

In this report, an international team of researchers analyzed and compared changes in gene expression associated with aging and disease in a region of the brain known to be affected in both Alzheimer's and FTLD. Comparing samples from healthy individuals ranging from 16 to 102 years old with those from diseased patients, the investigation uncovered striking similarity in the changes in gene expression patterns associated with aging and the neurodegenerative diseases.

"Surprisingly, these [diseased] samples contained the same aging-related changes as healthy individuals over the age of 80," relates senior author Jernej Ule of MRC Laboratory of Molecular Biology, Cambridge, U.K.

Aging-related changes were apparent in the diseased individuals as young as 50 years--"roughly 25 years before we would expect to see similar changes in healthy individuals," indicates James Tollervey of MRC, the first author of the study.

While the similarities were striking, the group also observed...