Gene linked to timing of onset of Alzheimer’s

A gene associated with Alzheimer’s disease has been thought to influence whether someone will develop the memory-robbing disorder. But new research suggests it more strongly influences when the disease develops in later years.

Ara S. Khachaturian, an Alzheimer’s researcher in Potomac, Md., and colleagues at several research centers studied the presence of one form of the Apolipoprotein E gene, called ApoE4, among 3,308 seniors enrolled in a major health study in Cache County, Utah. That community was selected because it has particularly long-lived residents.

Apolipoprotein E genes are involved in the movement of cholesterol in the body, and the ApoE4 version is one of the best-known genetic risk factors for Alzheimer’s among the elderly.

However, not everyone who has it develops the disease.

Khachaturian and his colleagues found that having a single copy was associated with earlier onset of Alzheimer’s, in the 60s and 70s, rather than 80s and 90s, and two copies pushed the onset even more toward the earlier part of old age.

The findings were published in the May issue of the Archives of General Psychiatry.

-- Jane E. Allen