Study found that children with the Alzheimer's gene e4 had differences in their brain development compared to children with Alzheimer's e2 and e3 forms of the gene. Washington: The Alzheimer's gene e4 associated with Alzheimer's disease may shrink brain regions and reduce thinking skills as early as childhood, a finding that may help researchers develop ways to prevent the disease from occurring, according to a new study. Prior studies showed that people with the epsilon (e) 4 mvariant o...