Tau pathology is the best pathological correlate with Alzheimer's disease. What is often overlooked in the study of Alzheimer's disease is the APOE gene. This

Tau pathology is the best pathological correlate with Alzheimer's disease. What is often overlooked in the study of Alzheimer's disease is the APOE gene. This comes as three forms, each differing from the other by only a few amino acids. These are called APOE2, APOE3 and APOE4. The most common form is APOE3, APOE2 and APOE4 are each present in about 6-10% of people (heterozygous). People who are homozygous for the APOE2 form almost never get Alzheimer's disease, whereas those who have the APOE4 form have a more than 50% chance of getting Alzheimer's disease before they die. So... there must be a link between the APOE gene and tau... since both are the strongest correlates with the disease, in pathology and genetics, respectively. However, you would be hard pressed to find a study that demonstrated a mechanistic link between these two factors (apart from Alzheimer's disease, of course). As a researcher in the field, I think this is one of the most intriguing aspects. Link to open access review on APOE in Alzheimer's disease: http://dx.doi.org/10.1016/j.neuron.2012.11.020 http://dx.doi.org/10.1016/j.neuron.2012.11.020 Edit: For those interested in a reputable collection of recent reviews on the biology of Alzheimer's disease: http://perspectivesinmedicine.cshlp.org/cgi/collection/the_biology_of_alzheimer_disease http://perspectivesinmedicine.cshlp.org/cgi/collection/the_b...