From this article Good Diets Fight Bad Alzheimer Genes:
The researchers are exhilarated to find that a diet high in Omega 3 oils and low in cholesterol appears to significantly reduce the negative effects of the APOE4 gene in mouse models.
The APOE4 gene is a known risk factor for Alzheimer's and is present in 50% of all Alzheimer's patients.
The main take-away message here is that good diets can alleviate the effects of bad genes. Of course nutritionists have had this general idea for a while, but it's nice to be able to show that this approach can be applied to specifically counteract the negative effects of Alzheimer's disease-related genes,"