New Alzheimer's Gene Found

Scientists have spotted another gene that may make some
people more likely to develop Alzheimer's disease.

The discovery may one day lead to new treatments, note the researchers, who
included Eric Reiman, MD, of the Translational Genomics Research Institute in
Phoenix.

Reiman and colleagues screened the genes of 1,411 people, including 861
people with Alzheimer's disease.

First, the researchers noted whether the participants had the ApoE4 gene,
which makes Alzheimer's disease more likely.

A total of 644 participants had the ApoE4 gene. Most of them had Alzheimer's
disease.

Next, the scientists analyzed participants' DNA, searching for genetic
patterns linked to Alzheimer's disease. The GAB2 gene stood out in that
search.

Ordinarily, the GAB2 gene thwarts the formation of Alzheimer's-related brain
protein tangles. But certain GAB2 gene mutations hamper that process, note
Reiman and colleagues.

The researchers tested that theory in their lab. They found that cells in
test tubes made the building blocks of protein tangles when the GAB2 gene was
turned off.

Reiman's team concluded that a healthy GAB2 gene offsets some of the ApoE4
gene's Alzheimer's risk. But a mutated GAB2 gene has the opposite effect,
worsening Alzheimer's risk in people with the ApoE4 gene.

The findings appear in the journal Neuron.

By Miranda Hitti
Reviewed by Louise Chang
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