MAPT and Alzheimer disease: Because we discovered that HNP neurons exhibited higher performance in several expected cellular functions—including transportation, translation, and metabolic processes—and participated more heavily in other chemical communications, regulation of innate immune response, and circadian rhythm, we wondered whether dysregulation of processes in these functions may lead to the loss of neuronal functions and the accumulation of tau pathology, which are hallmarks of several neurodegenerative disorders including AD.