Besides, the future employment of not-invasive retinal imaging and eye-based protein biomarkers for early diagnosis and monitoring therapeutic efficacy is widely fostered by the recent finding that the quantification of Aβ1-40/1–42 and total tau levels in the vitreous, an ocular fluid which is considered to be a direct indicator of the underneath suffering retina, has predictive clinical utility in the clinical practice of AD [76]. The gene discussed is MAPT; the disease is Alzheimer disease.