Like crime suspects yanked from a police lineup and held for additional questioning, several human chromosomes now face intensified scrutiny for possibly harboring genes involved in Alzheimer's disease. New data from a genome-screening study suggest that portions of at least nine chromosomes may be implicated in the development of the disease.
Inherited traits account for a portion of any person's risk of Alzheimer's, says Rudolph E. Tanzi, a neurologist at Massachusetts General Hospital in Boston. About 10 percent of people age 65 or older have the incurable, progressive dementia. Several rare genes that invariably lead to the disease have been identified, but most of the genetic factors in Alzheimer's remain unknown, Tanzi and other researchers suspect.