ROCHESTER, N.Y., Nov. 14 /PRNewswire-USNewswire/ -- The only
known genetic risk factor for Alzheimer's disease slows down the
brain's ability to export a toxic protein known as amyloid-beta
that is central to the damage the disease causes, scientists
have found. The research, published Nov. 13 by the Journal of
Clinical Investigation, provides new clues into the workings of
a protein known as apolipoprotein E4, or ApoE4. People who carry
two copies of the gene have roughly eight to 10 times the risk
of getting Alzheimer's disease than people who do not. The new
results mark a step toward resolving a longstanding question
that scientists have had about exactly how ApoE4 increases a
person's risk for the disease. The findings point to differences
in the way that amyloid-beta is removed from the brain depending
on which ApoE protein is involved. Scientists found that when
ApoE4 is present, the brain is less efficient at ridding itself
of the toxic material, because a molecule that is much slower at
removing the