Forgetfulness Can Run in the Family
Excerpt By Jacqueline Stenson, Reuter's Health

NEW YORK (Reuters Health) - Forgetfulness may run in the family, according to new research showing that a variation of a gene involved in memory is linked to poorer recall of past events.

"This study identifies and characterizes fairly in depth one gene that comes in two forms in the human population and...impacts on how well you remember things," said study author Dr. Daniel Weinberger, a neuroscientist and chief of the clinical brain disorders branch at the National Institute of Mental Health in Bethesda, Maryland.

In addition to this gene, several other factors can affect memory in healthy adults, including IQ, early developmental events and probably more genes, Weinberger told Reuters Health

The gene examined in the new study is known as BDNF, because it makes brain-derived neurotrophic factor, a protein that plays a role in memory formation, Weinberger explained.

About 15% to 20% of the population carries a genetic variation of BDNF known as metBDNF, he said.

In the current issue of the journal Cell, Weinberger and his colleagues report on a series of experiments with BDNF.

In one test, more than 600 adults were asked to recall story events. As hypothesized, people with metBDNF performed worse than those with normal BDNF.

Imaging tests indicated that people with metBDNF also had altered function in the hippocampus, the brain's memory center. Weinberger said it's possible that the genetic variation may make people at greater risk for or more vulnerable to the effects of conditions that impair memory and affect the hippocampus, including Alzheimer's disease, various psychiatric disorders and even normal aging.

At the same time, though, metBDNF may have some undiscovered beneficial effects as well, the researchers suggested.

In another experiment, the investigators explored how the two forms of BDNF protein acted when injected into rodent hippocampal cells in a laboratory dish. The normal BDNF spread robustly throughout the cells, whereas the metBDNF formed a clump inside the cells.

In effect, Weinberger said, the variation in BDNF appears to change the "zip code" of where in the cell the protein goes. And if it doesn't go to the appropriate parts of a cell, it can't play its role in memory formation.

The study did not find that metBDNF was related to all types of memory, Weinberger said, just so-called episodic memory that involves recalling past events.

The new results are in accordance with previous research showing that a variation of BDNF correlated with poorer memory in animals.

SOURCE: Cell 2003;112:257-269.

Reference Source 89

For more information on how to prevent other diseases, use
PreventDisease.com's "Quick Prevention Resources".